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What Will the Volt’s Generator Mode Feel Like?
GM has not let any of the media including myself experience driving in the charge-sustaining or generator mode in the Chevy Volt mules. There might be some concerns about how it will be experienced possibly leading to some negative press.
While I was at the Milford Proving Grounds I was told that many people who drive the car through the transition often don’t notice the engine going on and that it is not abrupt. Once running, RPMs are known to operate at several fixed points not matched to the accelerator and thus theoretically the engine could feel unnatural.
Car and Driver took its turn at a Volt mule wheel and though they too were unable to experience the generator mode, were able to get the following comment about it from Tony Posawatz, the Volt vehilce line director:
The work being done by the development guys as we speak is to create a gentle feathering of engine rpm, so you don’t even notice that the engine kicks in. And to try to operate at the right points and to transition the rpm points depending on the load you’re getting—to behave like someone would want it to behave.
You may get into a position under an extreme grade or hill climb, where the engine rpm will be pretty loud—running pretty hard. At a certain point in time that rpm will be relatively unpleasant. This is the challenge of different road loads: how can we keep the NVH reasonable for a customer?
Source (CarAndDriver)
May 4th, 2009 at 5:48 am
With modern car engines, the noise can be pretty muted. I am sure GM can figure out how to make the engine noise somthing we can live with. I like the idea of gradual changes in the rpms (feathering). This will make the engine even less noticeable as it is running.
As far as the actual drive experience goes (assuming you are deaf), we should not notice a jump in torque or power since the electric power should not change with the motor coming on.
Keep refining it GM. Lets have a nearly perfect test drive in a few months.
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May 4th, 2009 at 5:58 am
It is pretty obvious: GM wanted the first reports about the Volt to describe how wonderful an electric car it is. Not how strange it is to drive a gasoline car that does not rev up when you press the accelerator.
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May 4th, 2009 at 6:02 am
Not to mention the mules might lack much of the ICE vibration-damping stuff GM intends to put into the final Volts. The mules were intended for testing the Voltec drivetrain – but they do not have all of the Volt’s parts in them.
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May 4th, 2009 at 6:06 am
When I took my lone ride in the Prius, it was extremely obvious the ICE turned on. It was loud. To be fair, the drive was pushing the car and we were going up a very steep hill when it turned on.
I don’t know why this is a big deal though. A vast majority of us drive an ICE vehicle now. It is not like we are not used to turning on the engine. Sure, that doesn’t usually happen when we are driving, but is this really a big deal?
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May 4th, 2009 at 6:10 am
From the article:
You may get into a position under an extreme grade or hill climb, where the engine rpm will be pretty loud—running pretty hard. At a certain point in time that rpm will be relatively unpleasant. This is the challenge of different road loads: how can we keep the NVH reasonable for a customer?
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Again, do we really care? Today, when we drive up Pike’s peak, the engine works harder. It is expected. So what is the big deal? Why would this have to be different from any car on the road today? Are they concentrating on a problem that is not a problem?
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May 4th, 2009 at 6:20 am
On the part of the article reflecting what they did test, Car and Driver says
The Volt is by no means a sports sedan,…Acceleration is acceptable;…
and laters on says
…the future will feel surprisingly conventional…
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The saying “Damned with faint praise” comes to mind.
There is no reason someone will pay extra to have performance that is “acceptable” and “surprisingly conventional”. The performance part is where the Volt has natural advantages over ICE. Why not let the Volt be the Volt? It really should be creating “look at me I’m different” and “you have to get one” responses, rather than striving for “ho-hum” and the traditional GM “let it be bland.” I hope the final product will surprise us and actually be special.
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May 4th, 2009 at 6:22 am
I have Saturn Vue Hybrid. I don’t think there is a problem here. It does very well and I feel there will be some software modifications but then again I am not an engineer.
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May 4th, 2009 at 6:26 am
NVH? Translation, please.
As for the post itself, well, it’s very curious. I stick by my original point: If it is true that the transition is barely noticeable, surely a disclaimer that they are still perfecting it would be sufficient for independent observers who drive it through the cycle.
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May 4th, 2009 at 6:28 am
This sounds like a needless tweaking that could be showed off to the public right now.. I suppose they don’t want ANYbody to notice, which would be another selling point.
Since the engine is independent of the drive train, I imagine that at highway speeds one might not notice it either way.
Tibor -
Excellent point, I had not thought of that before. If they’re doing that, I hope it doesn’t weigh too much. I’d rather go without if so!
RB -
While that’s true, this is _still_ GM, and we can see a Voltec Caddy on the horizon, no? There are lots of people that are going to pay supremely unconventional car with performance that is merely conventional-feeling, except when taking off from stops.
Bruce -
Sorry to say, you may not be getting the best first-hand knowledge of hybrid cars if you’re drawing that experience from the hybrid Vue alone. You shall buy a Volt, yes?
NPNS!! -D~~
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May 4th, 2009 at 6:29 am
#8 FME III says
If it is true that the transition is barely noticeable, surely a disclaimer that they are still perfecting it would be sufficient for indepentent observers who drive it through the cycle.
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Apparently the issue is Posawatz’s comment
You may get into a position under an extreme grade or hill climb, where the engine rpm will be pretty loud—running pretty hard. At a certain point in time that rpm will be relatively unpleasant.
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May 4th, 2009 at 6:33 am
#10 RB says
Apparently the issue is Posawatz’s comment
You may get into a position under an extreme grade or hill climb, where the engine rpm will be pretty loud—running pretty hard. At a certain point in time that rpm will be relatively unpleasant.
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That could be, although GM could easily enough ensure that there are no such extreme grades on the test drive for the reporters.
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May 4th, 2009 at 6:48 am
GM wants the experience to be totally different for the drivers.. I bet you wont feel or hear the genset coming on or even running at hwy speeds. It will feel like an electric car with unlimited range… imagine that
Imagine if all these reviews coming out now would have said: “and then we felt the engine starting with an unpleasant shudder” .
Obviously they are still fine tuning this.. probably with muffler, induction system and engine mount tweaking. They may even use active sound cancellation tech on it.. if the stereo system is fancy enough.
The Volt will not be an electric car with a Honda generator that your crazy engineer dad put together in the garage.
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May 4th, 2009 at 6:49 am
The actual issue at hand is the efficiency.
We want mule data stating this is what the MPG was at specific MPH while the battery-pack was depleted driving in charge-sustaining mode.
How it will sound & feel is a red herring.
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May 4th, 2009 at 6:50 am
You may get into a position under an extreme grade or hill climb, where the engine rpm will be pretty loud—running pretty hard. At a certain point in time that rpm will be relatively unpleasant.
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Under an extreme grade, doesn’t a regular car engine rpm rev up the same way? With the sound proofing we may not notice it much but it’s there. I don’t see how it could be so much different with the Volt.
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May 4th, 2009 at 6:55 am
#8, FME III,
NVH = Noise, Vibration, Harshness
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May 4th, 2009 at 6:58 am
Thanks, charlie h!
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May 4th, 2009 at 7:12 am
From the article,
“Taking the point further, if the gas engine is only rated for 100 hp (our estimate of its power output), the 149-hp electric motor will only be able to make 100 hp. The upshot: the Volt will be quicker running on battery power than it will be when the gas engine is providing the electricity.”
This is an error on behalf of Car and Driver. At VoltNation last year one of the Powertrain engineers explained that the Volt’s power while in CS (charge sustaining) mode would come from both the ICE and the battery pack. The role of the ICE is to provide AVERAGE power.
So in many instances, the ICE will provide traction motor power as well as a small amount of power to charge the battery in a “buffer” zone, perhaps between 25 and 35% SOC. The ICE output will vary depending upon the driving conditions and the SOC of the battery. At some point, the ICE may shutoff.
In the instance of climbing a hill, the full 149 hp will be available, with power coming from the battery and the ICE. The question becomes one of when running uphill at full speed for extended periods, and the power draw drains the battery to the low point in the buffer zone, will the Volt then be limited to the power from the ICE only?
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May 4th, 2009 at 7:34 am
#1 nuclearboy Says: As far as the actual drive experience goes (assuming you are deaf), we should not notice a jump in torque or power since the electric power should not change with the motor coming on.
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For most current cars, the terms “engine” and “motor” can be used somewhat interchangeably, but for the Volt these terms have specific meaning:
The motor is electric.
The engine runs on liquid fuel (gasoline or E85).
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May 4th, 2009 at 7:47 am
It is my GUESS that the noise from the ICE is most likely no louder than a normal ICE but if you have been driving for say a half hour all electric in near silence and then the ICE comes on while climbing a steep hill you will know it. Getting rid of that sound has got to be tough. It is the nature of humans to notice any change in what we see,feel, or hear. Same with our cars we now drive. We are driving along and we may not know what happened but something happened that just didn’t feel or sound right.
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May 4th, 2009 at 7:53 am
The engine runs on liquid fuel (gasoline or E85).
_____________________
No, since gaseous hydrogen and natural-gas are used too.
Engine = runs by means of combustion.
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May 4th, 2009 at 8:02 am
#15 Charlie h says,
NVH = Noise, Vibration, Harshness
Thanks Charlie. I was wondering that myself.
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May 4th, 2009 at 8:02 am
it seems like there should be 2 modes for the ICE. Optimal efficiency mode and high output mode (for high-speed hill-climbing). My thinking is that they picked an underpowered ICE for the first gen. Maybe gen 2 will have an ICE that will be able to give optimal efficiency and highest output at the same RPM.
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May 4th, 2009 at 8:05 am
#17 BillR,
Thanks for pointing out this error in the Car & Driver article. I posted a comment over there calling it out. Hopefully, the author will read the comments and figure out his error.
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May 4th, 2009 at 8:05 am
John1701a, As far as I know, there are no plans for a hydrogen or natural gas version of the Volt.
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May 4th, 2009 at 8:14 am
You should not be too concerned about this.
My educated guess is that the Volt in charge-sustaining mode while on the hwy will get less hwy mileage than the new Prius.
Why?.. because the genset will invariably have losses generating power, lets be generous and say the generator is 95% efficient, then the inverter that drives the motor is also 95% and the motor itself is 95% thus the total chain efficiency is 85%.
The Prius is nearly 100% efficient in this mode since the engine is directly connected to the wheels (not even a transmission in the way). So wildly guessing the Volt will get about 43mpg in the hwy.. if you start to get a happy foot driver, a hilly road or some traffic then the Volt gets in the lead again.
The Volt will beat the c*** out of the Prius in short trips and city driving due to the engine in the Prius starting every time you step on the gas too harshly, and also due to the Prius having to meet pollution rules at these cold start up times.
The reason you should not worry too much about this is that for 78% of the public they will get much better mileage, and the other 18% are better off driving a Prius/Fusion.
The reason most people will have to buy a Volt is that they only have to fill up the gas tank every couple of years.
……………………….
#13 john1701a Says:
The actual issue at hand is the efficiency.
We want mule data stating this is what the MPG was at specific MPH while the battery-pack was depleted driving in charge-sustaining mode.
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May 4th, 2009 at 8:16 am
#24 MDDave Says: John1701a, As far as I know, there are no plans for a hydrogen or natural gas version of the Volt.
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That is correct. The Volt’s engine runs on gasoline or E85.
At one point, GM was talking about the EFlex architecture being able to support other types of range extenders, but this was a general architecture concept and not the Volt in particular. I believe this was so GM could take advantage of the hydrogen fool sell presidential initiative of the Bush era.
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May 4th, 2009 at 8:29 am
#17, BillR: “The question becomes one of when running uphill at full speed for extended periods, and the power draw drains the battery to the low point in the buffer zone, will the Volt then be limited to the power from the ICE only?”
Unless there’s some other source of power, then, yes, it’s limited to whatever the ICE output is.
But you only need full rated power when doing something unusual and then only for a short time. Merging onto a freeway needs full rated power for just 10 seconds or so – perhaps less. Any power demand less than what the ICE is capable of supplying is pushed back into the battery, so it’s available to help out later. It depends on the exact situation but it should be possible to climb a moderate hill while slowly charging the battery, if that’s what the vehicle algorithms call for. After climbing for a few minutes, there’d be enough juice to continue the climb without running the engine.
—
Another and important question is, how rough will the ICE be at max power? It’s a small car with an engine that’s big enough to propel it along decently, so the capability for a lot of noise and vibration is there. How good is the 1.4 as a motor? Do people praise its smoothness and quiet in normal cars?
If the noise and vibration can’t be muffled and damped away, there’s going to be some perceptible disconnect between what your foot is telling the car to do and what the ICE actually does. Whether or not this actually disturbs people is an interesting question.
I think it might have been best to let someone (Lyle, maybe), try the ICE-enable prototype on a hilly course and see what the reaction of someone unprepared would actually be.
How will GM actually program this? The algorithms are going to have a huge impact on perception of the vehicle.
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May 4th, 2009 at 8:35 am
Dont forget, the generator in the Volt is rated 50kw at full power, assuming it is 80% efficient means the ICE will have to provide 63kw and no more to the generator.. the ICE will never be loaded higher than this.
63kw is 85 horsepower, the Volt’s 1.4l engine is rated at 100hp.. thus the Volt’s ICE will never reach full rpm.
So mixing two guesses together the ICE in the genset will never go pass 4500 rpm.
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May 4th, 2009 at 8:37 am
#25 Herm Says: Herm Says: My educated guess is that the Volt in charge-sustaining mode while on the hwy will get less hwy mileage than the new Prius. Why?.. because the genset will invariably have losses generating power, lets be generous and say the generator is 95% efficient, then the inverter that drives the motor is also 95% and the motor itself is 95% thus the total chain efficiency is 85%.
The Prius is nearly 100% efficient in this mode since the engine is directly connected to the wheels (not even a transmission in the way). So wildly guessing the Volt will get about 43mpg in the hwy…————————————————————————————–
Yes, there are efficiency losses with the Volt genset, but the the Volt may have some efficiency gains with the engine disconnected from the wheels (e.g. using fixed RPMs).
But let’s say your 43 MPG figure turns out to be accurate. With a typical driving pattern, assuming you only charge overnight:
Vehicle ……………… Gallons per year
Volt (50 MPG) ……… 37
Volt (43 MPG) ……… 43
Prius (50 MPG) ……. 228
30 MPG car ………… 380
20 MPG car ………… 570
Obviously, the the Volt’s MPG is a lot less important than the 40 mile all-electric range, which you also stated.
Typical driving pattern:
• 30 days at 8 miles per day
• 50 days at 16 miles per day
• 240 days at 30 miles per day
• 30 days at 60 miles per day
• 3 days at 450 miles per day
11390 total miles per year
More info here:
http://mysite.verizon.net/vzenu6hr/ebay_pictures/GallonsPerYear.xls
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May 4th, 2009 at 8:41 am
Mixing a third guess in there, perhaps GM may take the Cruze’s 1.4l engine and modify it into an atkinson cycle like the Prius uses. That would drop the hp from 100hp to around 70% at 4600rpm. That may be right number of hp to make 50kw of electricity.
http://www.greencar.com/articles/toyota-prius-hybrid-synergy-drive-decreases-exhaust-emissions.php
The Prius uses the same basic 1.5 liter engine as the Toyota Echo, where the engine is rated at 108 horsepower at 6000 rpm. The Atkinson cycle allows the engine to be downsized to 76 horsepower at 4600 rpm while still being as efficient, or perhaps more so, than the Echo variant. Also, adding a supercharger to the Atkinson cycle results in the Miller cycle like that used in the Mazda Millenia.
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May 4th, 2009 at 8:43 am
From the article:
“While I was at the Milford Proving Grounds I was told that MANY people who drive the car through the transition often don’t notice the engine going on and that it is not abrupt.”
/random 3rd party hearsay is worth exactly what it sounds like it should be…
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Aside from that, I think the Car & Driver article finally susses out the problem, and it is bigger than just the transition…under stress, the generator is not working properly (or ‘as envisioned’).
“The work being done by the development guys as we speak is to create a gentle feathering of engine rpm…And to try(ing) to operate at the right points and to transition the rpm points depending on the load you’re getting—to behave like someone would want it to behave…At a certain point in time that rpm will be relatively unpleasant”
They use the example of a extreme grade of hill climb, because it elicits a very specific consumer reaction, as in ‘oh, we are never really going to encounter that in the real world’ or ‘we can put up with that every now and then,’ but there is no difference between going up a steep hill and passing someone on the highway, or accelerating hard. The car (and generator) is not reacting to the fact there is physically a hill, it is reacting to the amount of output the driver is expecting/requiring.
It seems more likely that the car simply does not function as intended at all in generator mode, rather than just for the changeover.
My guess as to why no one got to drive in extended range mode, is they didn’t want some guy from Car and Driver being in the car in generator mode, then slamming the gas and suddenly sounding like they were competing in a F1 race.
/’relatively unpleasant’
…but I’m open to being misguided here and interpreting what I am reading wrong, it is just a thought. Any thoughts on what, “At a certain point in time that rpm will be relatively unpleasant” means? Doesn’t sound like the transition is the big problem (although it might be), it sounds like a operational problem of the ICE.
/maybe the 3 banger wasn’t just discarded because they didn’t have one, and I’m kinda doubting 50MPG more if we are getting unpleasant engine noise due to high RPMs
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May 4th, 2009 at 8:44 am
I suspect that people driving the Volt will QUICKLY become “spoiled” by the wonderful silence of the all-electric mode, in which they will spend a lot (if not almost all) of their time. This may well be why even a modest change in the noise level may be especially noticeable. It’s all relative IMO. As always, I’m the silver lining type.
Be well,
Tag
LJGTVWOTR********NPNS
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May 4th, 2009 at 8:46 am
#28 Herm Says: the Volt’s 1.4l engine is rated at 100hp
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This is wrong. The Volt uses a 1.4L Atkinson cycle engine. This delivers 70-75 peak horsepower.
The 100 hp figure from the Car & Driver article was their uneducated estimate, and assumed Otto cycle, not Atkinson cycle.
As a comparison, the 1.5L Prius engine delivers 76hp:
http://www.toyota.com/prius-hybrid/specs.html
Since Toyota hasn’t listed the specs of their new 1.8L engine on their website, I have no idea what hp output that is.
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May 4th, 2009 at 8:47 am
Confirmed what Lyle posted in his test drive comments:
Does it work: Yes
Does it work as it is intended to in normal condition: Yes
Does it work as it is intended to in limit condition: Yes, but it can fell unnatural when you compare it to current ICE car and could “break” the user experience for some.
Do they understand the issue and what need to be done, my guess is YES.
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May 4th, 2009 at 8:56 am
BillR @ 17, thanks for correcting at lease some of the apparent misinformation in this Car and Driver article.
My understanding is the engine will vary its RPM and power output based on the SOC of the battery, and not on the current load. So at point A the ICE starts and runs at a low RPM producing about 8 KW, the average power needed in low speed urban conditions. If this power level is not enough to sustain the SOC, the SOC will decrease to point B, where the ICE will “feather up” (slowly increase RPM) to a midpoint RPM producing about 24 KW, the average power needed for highway conditions. If this power is not enough, say because of driving at high speed up a grade for an extended period, the SOC will decrease to point C, where the ICE will “feather up” to its maximum power level, producing about 48 KW.
Now the problem discussed seems to be if, when the SOC is below “C” you pull out to a viewpoint. With the SOC below C, even though the car is stopped, the ICE will continue to run at high power and this would be unpleasant, perhaps creating in your mind the idea its going to suddenly power the wheels and propel the car off the view point cliff. So what the GM engineers are working on is providing some throttle back when load drops off, even though the SOC is still calling for high output. Of so it seems to me.
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May 4th, 2009 at 8:56 am
I would prefer the ICE stay in its optimal fuel/power efficiency range reguardless of where the accelerator is, but I may not be typical and that may cause people problems with the feel of the car.
It appears Chevy is trying to make the transition seamless for all drivers, and that may not be the best thing to do. It is revolutionary to be driving all electric all the time and people will adapt. I know my brother-in-law currently has a Camry Hybrid and said it took him just a couple of weeks to become accustomed to the different sounds. People choosing this technology at the beginning, expect something different and, I think, are willing to make that adjustment.
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May 4th, 2009 at 9:02 am
#35 Van
Wos!! I had not thought about sitting at a red light and the engine reving at 3500 rpm. That would be unpleasent and unnerving. I can, in my mind see some old person just crapping at the thought of their expected take off. expecting to leave rubber and hear the scream of spining tires. And then there is that 17 year old boy I keep bringing up, a complete look of dissappointment that the tires didn’t squeal.
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May 4th, 2009 at 9:03 am
#31 statik Says: …but I’m open to being misguided here and interpreting what I am reading wrong, it is just a thought. Any thoughts on what, “At a certain point in time that rpm will be relatively unpleasant” means? Doesn’t sound like the transition is the big problem (although it might be), it sounds like a operational problem of the ICE.
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I believe the range extended mode still has a few software bugs to work out before it’s totally smooth, and that’s why no test drives yet. I’ll bet we see range extender test drives within the next 2 months. Not to worry.
As for full power being available all the time, remember that 30% of 16kWh is a lot – way more than most hybrids today. Calculations for uphill driving show no real world problems. You have to drive 80MPH for 20 miles constantly up a steep hill to lose battery power. If the 20 mile 6% grade has any curves or anything else that slows you down, the battery will recharge. If the 20 mile hill has any level or downhill spots, the battery will recharge.
Don’t worry.
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May 4th, 2009 at 9:12 am
Van & BillR
Very good posts – thanks. Your ideas sound pretty reasonable.
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May 4th, 2009 at 9:17 am
It may be information overload for some, but I wouldn’t mind a light or sound that my ICE has turned on, as well as actually hearing it myself (which i may not if my stereo is cranked). I would also like a tachometer. A display showing power output from the batteries and the ICE would be nice too. The more information the better (for me), but I know this would drive some people nuts.
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May 4th, 2009 at 9:22 am
This is not important to me. As long as it works and gets optimal efficiency. You should be able to shut it off or nearly that at a stop light and just rely on the battery, but either way why should people care? We’ve developed a sense of what’s normal with cars by using them for so many years, but they were alien technology to us when they first came out. Let people adapt to something new. Explain it to them.
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May 4th, 2009 at 9:23 am
Regarding the noise and vibration issue… I have a 2008 Malibu with a 4 cylinder, 169 bhp engine (don’t know the displacement). This baby is as smooth and quiet as any ICE I have ever owned. Therefore, I don’t see why the genset in the Volt should be any problem. Yes, if I stomp on the gas peddle, I hear more engine noise, but isn’t that what is expected? Even then, it is not anywhere near annoying.
I would think that the only issue might be at initial start up of the genset where the vehicle might shudder a bit. Or am I missing something?
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May 4th, 2009 at 9:23 am
#29 Dave G:
Thanks for the update on what those numbers mean. Looking at the spreadsheet, the only major difference for me would be the highest milage, where I would have more trips but not as long, say 12 days @ 120 miles.
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May 4th, 2009 at 9:26 am
I can’t imagine such a small engine is ever going to be THAT loud, whatever RPM it’s running at.
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May 4th, 2009 at 9:27 am
This is not right, the battery solely sources the power demands of the motor.. until it is fully dead.
The generator senses the state of charge of the battery (which changes slowly since its a large battery) and ramps up slowly to keep the charge up, up to its rated maximun power. It should not respond instantly due to the drivers throttle demand like a Prius does.
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#31 Statik says:
The car (and generator) is not reacting to the fact there is physically a hill, it is reacting to the amount of output the driver is expecting/requiring.
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May 4th, 2009 at 9:31 am
Good article, Lyle. I hope GM can “feather” the sound of the rpm changes and the ICE coming on. To me the rpm sound level should never exceed the level of speed the car is currently going unless in a dire situation where the rpm must be high to make the car go. Like going up a very steep hill. It will be very interesting to see the results of some test drives using the ICE in varying conditions. I hope that happens early this summer and fall.
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May 4th, 2009 at 9:35 am
#42 – CBK – I too have a 2008 Malibu with a 4cyl. It is quiet and a great car- I believe they added engine throat noise to it so it can “sound like what we are use to”. The CTS also did this.
The engine is extremely quiet – and if you want to hear your ice running the engineers will have to ads sound. I believe the larger problem will be the pedestrians not hearing you come up behind them. I have already been startled a few times by hybrids pulling out of the grocery store parking lot. I now look for taillights etc…
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May 4th, 2009 at 9:41 am
#45 Herm said:
(in response to #31 Statik saying, “The car (and generator) is not reacting to the fact there is physically a hill, it is reacting to the amount of output the driver is expecting/requiring”)
This is not right, the battery solely sources the power demands of the motor.. until it is fully dead.
The generator senses the state of charge of the battery (which changes slowly since its a large battery) and ramps up slowly to keep the charge up, up to its rated maximun power. It should not respond instantly due to the drivers throttle demand like a Prius does.
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Thats not right. The ICE powers the wheels directly (through the generator) for all intents and purposes after the battery is depleted, the ICE reacts to the demad needed by the driver and adjusts accordingly, the battery is taken out of the loop. If more power is required than the ICE can put out, the battery is then supposed to dip in past the customer depletion point and make up the difference. The battery after it is dead is used strictly as a buffer if it is needed.
This is where they are having trouble I think, the ICE is over revving and/or the battery is jolting the car when excess power comes back online to increase the performance. When the battery goes below the depletion point, it will be recharged by the regen braking, or through a trickle charge off excess power on the ICE slowly.
Here is the quote from Volt chief engineer Andrew Farah on it:
“When you get to the customer depletion point, the engine will come on seamlessly as it’s supposed to. But when the engine comes on to spin the generator, it does so with the idea that we’re generating electric energy to drive the wheels, not to charge the battery. People say the engine comes on to charge the battery, but that’s not what really goes on. The engine comes on to make enough electric energy to turn the wheels, because the wheels are always turning electrically.”
“…if you’re trying to go up a hill with only basically half the power capability? That’s where the battery comes back into play. Because the customer depletion point is not full depletion, there’s still energy available. That’s by design. The idea is during certain other peak situations such as climbing a hill or merging into traffic, you will actually take some more energy out of the battery. So you may actually come down a little bit below customer depletion level.”
“And then when you take your foot off the gas, as an example when you’re done doing the merge, we had taken a little bit out and the battery has a little less in it. So what we’ll do then is we will opportunistically put that energy back into the battery either through regenerative braking or if we have to we will take some of the energy that’s not needed to turn the wheels and bring the battery up to the customer depletion level.”
“So we don’t recharge the battery. The customer wont actually see any of this, as their electric range indicator in the car will only say zero. We are actually using that battery at that point as a peak buffer and we will keep trying to recapture energy as the opportunities allow.”
http://gm-volt.com/2008/08/25/what-happens-in-the-chevy-volt-past-the-customer-depletion-point/
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May 4th, 2009 at 9:54 am
there needs to be lot of improvement to be done in the gas recharging engine
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May 4th, 2009 at 9:55 am
If there is a tachometer on the dashboard display screen for the engine rpm’s – it should be re-labeled to “generator output”. That would help the non-technical driver understand why the engine is cranking out 2,000 rpm’s while sitting at a stoplight or stuck in traffic on the 405 fwy.
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May 4th, 2009 at 9:57 am
Don;t forget Diesel for Europe. The only true green engine choice available, just not in the USA.
Hydrogen fuel cell is probably in line for gen 2 or 3 of the Volt. If GM lasts that long.
ICE, sounds like there is a lot work to be done. I would expect there will be regular software updates (ala Microsoft) as engineers continue to tweak the software and get feedback from customers. It would be funny to get an email from Chevy saying for you to come get SP1…
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May 4th, 2009 at 9:58 am
Bottom line here is you’ve got a 3500ish lb. car and a 90ish horsepower engine.
The genset is going to suffer some efficiency losses (could be anywhere from 5% to 25% (85 to 68hp (ref. 90hp to start). The little bit of battery reserve (whatever GM has alotted south of 30% SOC) left for assisting in hybrid operation will get eaten up quickly in many circumstances and then your left with something that’s got a sick power to weight ratio [that's just sick sick, not wicked sick]. That poor little 1.4 is going to be screaming for all it’s worth to try and keep up and that’s NOT going to get you 50 mpg.
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May 4th, 2009 at 10:01 am
I’m not really worried if the motor actually makes noise. That’s what they do. If you aren’t into hearing a motor running when you drive, buy a bicycle. The big difference will be the engine will not be in tune with the gas pedal like on a conventional car. Prius, Honda civic hybrid, Ford Hybrid, GM/Chrysler 2 mode hybrid drivers experience this to a certain extent every day.
The big questions are this:
1: When the Volt comes out will it be embraced with open arms like the Prius was? (I doubt it because it’s from an evil American corporation).
2: Will it be a trouble free (few minor recalls at most) launch? This to me is critical. You can test the hell out of components but when the suppliers start mass producing those components, problems pop up. Both G.M. AND their suppliers really REALLY need to have their, ummmm STUFF! together for this one. The future of American manufacturing may well rest on it.
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May 4th, 2009 at 10:04 am
It really amazes me at the level of knowledge available on this web-site from the comments I read. I must congratulate some of you for the informative comments I get to read on a daily basis. I will not try to name those I am thinking about, but we all know who they are. I just want to say thank you. It is a pleasure to read the comments when we stay on subject.
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May 4th, 2009 at 10:06 am
#50 CorvetteGuy Says:
If there is a tachometer on the dashboard display screen for the engine rpm’s – it should be re-labeled to “generator output”. That would help the non-technical driver understand why the engine is cranking out 2,000 rpm’s while sitting at a stoplight or stuck in traffic on the 405 fwy.
===================
How are those Camaro deliveries coming along? Production tipped 8,000 total today in Oshawa.
If you haven’t started getting them, you’d think you’d be good by the end of the week. If there are 2,000 dealer 6 cyl. probably to get out early, and then 15,000 pre-sales on order. Thats close to half fufillment of the early books.
/have to be somewhere, and we don’t have 7,000 of them sitting here
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May 4th, 2009 at 10:10 am
I am sure they are doing many things such as the weight of the ICE flywheel.
Many times different weights are used for different racing applications and desired behavior of the engine winding up and down. It’s a matter of tuning. Sounds simple but it takes time.
Until we know the specs of the generator all we can do is guess…
But I am sure flywheel weight is part of it. It many end up being an extremely refined ICE balanced to the specs of a race car to get rid of unwanted vibrations etc..
Get the Z06 guys in on this part. I too am curious about how much is lost in the “drive line” or “Gen Set”.
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May 4th, 2009 at 10:24 am
#54 N Riley says:
It really amazes me at the level of knowledge available on this web-site from the comments I read. I must congratulate some of you for the informative comments I get to read on a daily basis. I will not try to name those I am thinking about, but we all know who they are. I just want to say thank you. It is a pleasure to read the comments when we stay on subject.
——————-
I love the site too. So Lyle gets my thanks for that. I don’t know if it is the topic that brings a certain crowd out to play, or our relatively obscurity from the general internet population…but I can’t find another example of such a mature, well-rounded (mostly sane…like yourself, heh) group of people on the internet.
Seriously, if it wasn’t for the other commentators and there attitude/insight and comradery, I probably wouldn’t even come around that much, or post at all…maybe I’d just check in a couple times a week to see what is happening with the project and be on my way. I probably hit up a couple dozen sites a day, thousands in a year, and don’t leave a message on any of them….weird.
Sidenote: I don’t even mind the sidetracks, as long as they are somewhat related, articulate…and don’t divert the thread too much (the latter I have been guilty of more than a few times…but I’m working on it)
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May 4th, 2009 at 10:27 am
#35 Van
What you said sounds reasonable to me. But, of course, lots of things said on this site is way over my head. I would think that if the ICE is at a very high rpm and the car slows to a very slow speed or is stopped, the ICE should reduce its rpm to a low speed or down to a “normal” idle rpm. Once the car is started up and a certain speed is reached, the ICE rpm could be adjusted upward. The rpm could be adjusted upward as the speed of the car is increased. Lots of “little” things for the engineers to work out with the software team.
A volt driven on a daily basis for commuting less than 40 miles would very rarely ever experience high rpm. It would work just great for the vast majority of drivers.
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May 4th, 2009 at 10:31 am
This is all a confort and “Driving Culture” issue. Nerds like us will understand why and even current Prius owners will understand why because the Prius engine sound is not the same as in a normal car. This will just take some vibration dampening and sound deadning material. Remember the digital Camera? It doesn’t ned to “Click” when you take a picture, but it does because that’s what people need to hear to familiarize it with a real camera. Why not offer an “Ambiance” package that makes a humm directly proportional to the MPH of the car. Using that and dampening sound/vibration will solve the problem, or blast your steroe to the “2 Live Crew”…
Other than that, just build my Volt DANGIT.
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May 4th, 2009 at 10:31 am
12 Herm
They may even use active sound cancellation
- – - – - – - – - – - – - – - – - – - – - – - – - – - – - –
I agree with Herm on this one.
The Volt is not a vroom vroom sports car. It is a fast yet efficient and very high tech car. Why would GM want any sound coming out of this unit at all? Noise cancellation technology – like the Bose or Sony headphones – should be able to remove all the sound from the engine.
Vibration damping would be a bit trickier but with a gel-filled shock absorbing system there should be no vibration from the ICE genset either. Active vibration damping systems would probably add too much to the cost but would work great as well.
Once you’ve removed the actual engine noise you can replace it with simulated audio qualities of the drivers choice. Why not? The accelerator pedal is electronic so the vehicle computer could use that as an input (factor in the current speed, direction, and cornering data) to make the volt sound like any vehicle you want.
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May 4th, 2009 at 10:35 am
#42 CBK
“I would think that the only issue might be at initial start up of the genset where the vehicle might shudder a bit. Or am I missing something?”
——————————–
I think you are not missing anything except most people would not want the ICE to be at high rpm when stopped or going very slow. The comment from “old man” (#37) comes to mind. I sure do not want high rpm at a stop sign or stop light. Other than that, there is not real problem. This is something GM should be able to work out easily. If not, they are in deep trouble software wise.
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May 4th, 2009 at 10:37 am
51 Adrian
Hydrogen fuel cell is probably in line for gen 2 or 3 of the Volt. If GM lasts that long.
============
I doubt it. The Volt cost too much as it is w/out a brazillion dollar fuel cell in it. Not to mention a million othe problems regarding the h-word.
Also regarding software updates. They would most likely be done via OnStar.
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May 4th, 2009 at 10:48 am
@carcus1
“The genset is going to suffer some efficiency losses (could be anywhere from 5% to 25% (85 to 68hp (ref. 90hp to start). The little bit of battery reserve (whatever GM has alotted south of 30% SOC) left for assisting in hybrid operation will get eaten up quickly in many circumstances and then your left with something that’s got a sick power to weight ratio [that's just sick sick, not wicked sick]. That poor little 1.4 is going to be screaming for all it’s worth to try and keep up and that’s NOT going to get you 50 mpg.”
Good point. Considering the genset is spec’d out for a MAX 53KW of power, that translates to approx 71.11HP. So if there’s a 25% loss from the genset, theoretically you will need ~218HP from the 4cyl ICE.
I guess if they need eke out more from the ICE a turbo charger os supercharging is an option. HOWEVER, the Generator will have to be upgraded. I have a feeling the generator is the 75KW UQM model tuned to operate at 53KW only just to last longer.
Of course that’s just IMHO.
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May 4th, 2009 at 10:50 am
Typical old school dinosaur company mentality. Hide any issues as long as possible instead of getting them out there into the public realm to “crowd source” the issues. It’s 2009 GM, not 1950. Where’s this new thinking we keep hearing about?
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May 4th, 2009 at 11:01 am
Side notes:
According to GM this morning…they are still selling Saturn and ‘…a number of potential buyers have surfaced’…’and will look to secure an agreement with a specific buyer later this year’ (oh to dream of receiving that $1)…no word on HUMMER, heeh
http://media.gm.com/servlet/GatewayServlet?target=http://image.emerald.gm.com/gmnews/viewmonthlyreleasedetail.do?domain=3&docid=54073
Also, GM just announced that Q1 2009 results will drop Thursday, May 7, 2009 at 7:00 a.m.
http://media.gm.com/servlet/GatewayServlet?target=http://image.emerald.gm.com/gmnews/viewmonthlyreleasedetail.do?domain=3&docid=54077
…and they are webhosting the largest picture of a Volt mule (w/tech center) ever, lol (3meg JPEG FTL) – dial up users, DO NOT CLICK
http://gm.wieck.com/forms/gm/X09SV_CH020.jpg?download=014498
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May 4th, 2009 at 11:01 am
#63 Hey, CaptJack,
Do you happen to know what UQM claims are for efficiency? The way I understand it, the efficiency would vary with load and temperature. Maybe there’s an average or a chart on a spec sheet?
++
I’m thinking performance would have been quite a bit better with a nice little turbo diesel (lower rpms, more power) instead of the gas 4 banger , if the weight penalty didn’t hurt too much.
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May 4th, 2009 at 11:04 am
People sure are reading an awful lot into the fact that GM isn’t showing off the charge-sustaining mode yet. I liken it to an artist and his painting; he isn’t ready to show off his work until he feels it is ready. Many artists never show works-in-progress; this doesn’t necessarily mean that something is terribly wrong with the work, it only means the artist wants it to be perfect before other people see and judge it.
Don’t sweat the small stuff. The car is still more than a year away from release. They’ll work it out.
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May 4th, 2009 at 11:06 am
______________________________________________________
ICE Range Extenders will serve as an excellent pragmatic 10 year (or less) bridge solution while battery KWH/LB, KWH/$, and infrastructure quick charge mature to a tipping point that makes it more economical and convenient for long range electric cars to be pure BEV.
That waiting period will be halved for the early adopter consumers willing to pay a price premium for long range BEV’s (~300+ miles all electric range).
With regards to the ICE powering on/off behavior, it gets down to what algorithm provides the best blend of results. Coding such an algorithm requires determining which programmed task take precedence over another programmed task. Making those determinations in the coding process is often subjective such as determining how much to use the battery (requiring additional short ICE charge cycles) to serve as an added available power reservoir (buffer) during sudden acceleration under extended ICE mode.
GM has an engineering team of which each member of that team probably has a different idea of how the ICE algorithm should behave. Large engineering teams tend to gravitate towards more complex solutions rather than adhering to KISS. The Volt ICE algorithm will end up being a complex consensus by committee which is a much more involved coding/testing process than one or two guys coding what they think is best. I would put good money that the most spirited debates within the Volt Program engineering team has been over the behavior of the ICE algorithm.
______________________________________________________
Electric Cars + Nuclear Energy = American Energy Independence!
______________________________________________________
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May 4th, 2009 at 11:07 am
#35 van says
Now the problem discussed seems to be if, when the SOC is below “C” you pull out to a viewpoint. With the SOC below C, even though the car is stopped, the ICE will continue to run at high power and this would be unpleasant, perhaps creating in your mind the idea its going to suddenly power the wheels and propel the car off the view point cliff. So what the GM engineers are working on is providing some throttle back when load drops off, even though the SOC is still calling for high output. Of so it seems to me
——————————————————–
Whether this aspect is the problem or it is something else, it seems to me to be late in the day to be figuring it out. After all, this issue was evident from the moment the original concept was announced. As it is a power-train issue it is one that can be evaluated in the original and subsequent mules, which they have had for a while. Now life is getting harder because the move into the final body requires that weights and dimensions become fixed, so things like the flywheel are harder to change around. Making the ICE speed proportional to accelerator movement is basically different from making it in relation to battery SOC. Is the problem so difficult, or have they not been paying attention to it?
So I am going to pretend that we never heard of this matter and that things will be great.
I hope so.
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May 4th, 2009 at 11:11 am
Maybe they do need to let Lyle drive the mule until the ICE comes on and get his response to it. Plus some driving with the SOC at the lowest point so the ICE stays on. They could require him to keep his mouth shut until they OK’d him to release the report. Apparently it worked the last time. Why not now? How about it, GM. I know Lyle would do it. To get another opinion from a small critic allow Statik to do the same. He would give an honest reaction. I feel sure Statik could be trusted to “clam-up” for a while. Well, I think so. Statik?
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May 4th, 2009 at 11:14 am
#65 statik –> nice picture; thanks.
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May 4th, 2009 at 11:16 am
#70 N.Riley says ” I know Lyle would do it. To get another opinion from a small critic allow Statik to do the same. He would give an honest reaction. I feel sure Statik could be trusted to “clam-up” for a while. ”
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Lyle would do it. Statik would blurt it out.
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May 4th, 2009 at 11:16 am
Day 4 of Chrysler’s quick, 30 day bankruptcy…not going so well. The ‘non-TARP’ bondholders got a delay to until tomorrow at 2:30, so no 363 motion today.
They also had these comments:
——-
“The process is “tainted” because it was dominated by the government, the lenders argued in papers filed today in U.S. Bankruptcy Court in Manhattan. The group also said the short period of time given to evaluate the sale was improper….
The group, calling itself Chrysler’s non-TARP lenders, in reference to the Troubled Assets Relief Program, seeks to block the proposed sale to an alliance led by Fiat SpA…The group said secured lenders who agreed to the Fiat deal, such as JPMorgan Chase & Co., Citigroup Inc. and Goldman Sachs Group Inc., were conflicted because they had also accepted TARP funds.
The sale “improperly attempts to extinguish their property rights without their comment,” attorneys for the objecting lenders wrote in court papers. “The sale motion should be denied because it seeks approval of a sale that cannot be approved under the bankruptcy code,” they argued, adding “the court should not permit a patently illegal sales process to go forward.”
http://www.bloomberg.com/apps/news?pid=20601087&sid=aLI_HoCr38DA&refer=home
…and it is on.
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May 4th, 2009 at 11:17 am
Van 35
I think you hit the answer right on the head . Simple .
A TPS (throttle position sensor) connection to the gen-set relative speed would solve the problem because even if there was a signal calling for the generation of more power it would over ride that command and the gen-set would run according to the relationship of the relative position of the sensor at that time .
even if there was a call for more power as the pressure on the accelerator is released the gen-set would slow down accordingly . Just what a person would expect to happen .
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May 4th, 2009 at 11:21 am
No flywheel, not needed with the mass of the rotor in the generator. The generator is directly coupled to the engine.
You guys are making too much of this.. I like the idea of the genset throttling down when the car comes to a stop.. not idling but running at a moderate, in-audible setting like 1500rpm. You see?.. simple solution, and it stumped GM for several months. Just a few parameters changed in the code..
…………………………..
#69 RB says:
Now life is getting harder because the move into the final body requires that weights and dimensions become fixed, so things like the flywheel are harder to change around. Making the ICE speed proportional to accelerator movement is basically different from making it in relation to battery SOC.
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May 4th, 2009 at 11:23 am
#70 N Riley said:
Maybe they do need to let Lyle drive the mule until the ICE comes on and get his response to it. Plus some driving with the SOC at the lowest point so the ICE stays on. They could require him to keep his mouth shut until they OK’d him to release the report. Apparently it worked the last time. Why not now? How about it, GM. I know Lyle would do it. To get another opinion from a small critic allow Statik to do the same. He would give an honest reaction. I feel sure Statik could be trusted to “clam-up” for a while. Well, I think so. Statik?
——————-
#72 RB said:
Lyle would do it. Statik would blurt it out.
=======================
Hey!
…mumble, mumble, mumble
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May 4th, 2009 at 11:30 am
#55 statik
I ran a search on Saturday through GM Inventory System: Las Vegas has 1 Camaro SS. That’s the only dealer within 500 miles of us here in So Cal. The bulk of the SS models seem to be in Texas.
I think us Californians are getting the short end of the stick. Maybe something will happen this week.
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May 4th, 2009 at 11:40 am
wrong math.. the ice would have to provide 95hp if the genset was 75% efficient to generate 53kw of electricity.. and it is very possible 75% may be what it is at full output, hopefully up to 95% at 25kw output.. the generator will need liquid cooling for sure.
Does anyone have any real numbers on the generator and motor?
………………………..
#63 CaptJackSparrow Says:
Good point. Considering the genset is spec’d out for a MAX 53KW of power, that translates to approx 71.11HP. So if there’s a 25% loss from the genset, theoretically you will need ~218HP from the 4cyl ICE.
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May 4th, 2009 at 11:45 am
A few more semi-uneducated ramblings on the genset:
- Generators efficiency drop off when operating outside of their designed rpm. So, depending on what this rpm vs efficiency chart looks like, it may be that the engine turning at a reduced rpm really doesn’t result in much electrical output (less power in AND less efficiency in the conversion results in a lot less power out).
- Heat will cause a loss of efficiency also. So cram an ICE and a generator into a subcompact car and run them up to speed and your going to get some heat. If you can’t dissipate the heat fast enough then you might get into a power fade situation where the genset can’t work hard enough to make up for the efficiency losses due to increased heat.
GM’s probably got their hands full.
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May 4th, 2009 at 11:49 am
Please Lyle, could tell GM that selling OPEL to FIAT-Chrysler will another big mistake. Even though the Grrman Government refuses to bail out GM-OPEL, GM can still find a way to keep OPEL. For years, OPEL has proven being an active member of GM family. OPEL’s problem is not OPEL’s fault, GMknows this better than anyone else. For someone who used to live in Europe, OPEL is an important car maker and name. Please GM, just don’t do this!.
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May 4th, 2009 at 11:50 am
#54 N. Riley said: “…It is a pleasure to read the comments when we stay on subject.”
I echo your sentiments about this site in general. I enjoy coming here to chat with other car enthusiasts on a daily basis. By and large, the posters that are “regulars” usually are very respectful and thoughtful of others, and provide a wealth of insights here not available really anywhere else. I’ve learned so much in the time since I started coming here and that’s attributed to people such as yourself and others. So thank you too!
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May 4th, 2009 at 12:01 pm
How much does the ICE weigh? If you took the ICE out, wouldn’t their be enough room under the hood for an additional battery pack that weighs about the same? Wouldn’t that be sufficient to maybe bump up the total electric range to 50 or 60 miles? Maybe 100? The “T” shaped battery pack doesn’t need to be the ONLY battery pack in the car. As I understand it, the Tesla has battery packs stuffed in every nook and cranny.
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May 4th, 2009 at 12:02 pm
I always thought the requirement to drive at 100mph with a depleted battery was excessive.. 80mph would be fine.
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May 4th, 2009 at 12:03 pm
Of interest:
GM HQ Canada out of Oshawa announced today that GM drew down 500 million in ‘loans’ out of Export Development Canada ‘….to manage its normal operational needs while it works to complete its business restructuring plans’ on thursday.
This is the first actual ‘real dollars’ draw since they gave loan support back in december (GM didn’t want to take it at the time because it was conditional….times change)
More infor at the jump:
http://media.gm.com/servlet/GatewayServlet?target=http://image.emerald.gm.com/gmnews/viewpressreldetail.do?domain=880&docid=54079
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May 4th, 2009 at 12:05 pm
Probably the biggest issue is making sure the ICE RPMs are not high when stopped, for example, at a stoplight. A roaring engine when stopped would be very annoying and possibly confusing to some drivers. Many would think the “idle” is broken. It would be a fun spectacle to folks who dislike PHEVs.
So to seem like “a normal car” the ICE needs to respond more to instantaneous vehicle propulsion needs than to the state of charge of the battery. It’s not a technical problem, but a perception problem in a world that has been wired over the years to expect a certain operating profile for a car’s engine.
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May 4th, 2009 at 12:07 pm
“Typical driving pattern:
• 30 days at 8 miles per day
• 50 days at 16 miles per day
• 240 days at 30 miles per day
• 30 days at 60 miles per day
• 3 days at 450 miles per day
11390 total miles per year”
Where are you getting these numbers you post repeatedly? The federal average miles driven is 15,000 for one thing. The average commute is 36 miles. These numbers seem to be taylor made to promote the Volt, not actual real world numbers I found on a quick google search. I’m assuming they are YOUR typical driving pattern, not an AVERAGE typical driving pattern.
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May 4th, 2009 at 12:14 pm
#78 Herm,
Not what you’re asking for but I’ll put the engine numbers up as a data point anyway. ( this is family 0 1.4 l GM)
1.4 L Straight-4 (1364 cc): 73.4 mm (2.89 in) bore, 80.6 mm (3.2 in) stroke, 10.5:1 compression, 90 hp (66 kW) @ 5600 rpm, 125 N·m (92 lb·ft) @ 4000 rpm.
http://en.wikipedia.org/wiki/GM_Family_0_engine
Note: that 90 hp is at 5600 rpm. Pretty sure GM’s not going to run the volts engine at 5600 rpm in any circumstance.
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May 4th, 2009 at 12:17 pm
#62 k-dawg
Also regarding software updates. They would most likely be done via OnStar.
————
I’ve heard this referenced several times before on this site, and other requests about making the interface “skinable”..
Neither of these are likely to happen (extremely remote is a good shot at the probability of this coming to pass)
Updating firmware over a wireless link is a generally really bad idea, it’s not even recommended for updating routers this way (Cisco, Linksys, etc always recommend a hardwire), let alone cars. Also, consider that not everyone will have OnStar
I’ve had firmware updates done to my Honda van before – ALWAYS, ALWAYS done at dealer – I really don’t seem them wanting to change that with the Volt. They WANT folks to go back to the dealer every now and then, it’s a revenue source. Given the consequences of this getting messed up by the end user, and killing your car, SW updates are going to happen at the dealer – Period. – And they generally don’t like doing them, unlike the monthly MS firedrill – If an embedded system is working, generally best to leave it alone..
As for UI skins, that ain’t gonna happen either (unless they are provided by GM), why would they, it just opens up the software to more folks, and more potential problems, just to change the look/feel of the interface – This isn’t an IPOD, its a car, and software mistakes (crashes, untimely reboots, etc) can have very serious consequences (aka human safety, and then liability), so I just don’t see GM seeing that creating an “open API” or “customer interface” is going to really be something that they will sanction in Volt G1.. If your lucky, you’ll get Onstar mailing you monthly consumption/usage stats from your car (for a fee of course). That’s it.
Now 3rd party hacks, that’s another story, as it’s not GM’s problem if you “brick” your car.. I seriously doubt they will go to extremes like an Xbox 360, with signed & encrypted code, etc.. to protect the code, but they aren’t going to just OSS the Volt sources anytime soon, either
Bottom line, the Volt isn’t going to change the status quo when it comes to SW updates or user access into the SW.. You can dream, but it just isn’t realistic
My two cents – GuyMan
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May 4th, 2009 at 12:23 pm
Who cares about the engine RPM being loud when you’re climbing a steep grade or demanding high performance? We’ve gotten used to that one over the last 100 years! I think we’ll be ok!
Suddenly we’re all too pompous to hear the engine make noise? (half joking). If we already know it’s on, and know we’re driving the car hard, i would figure that noise would be something that we all just accepted and wouldn’t consider a burden.
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May 4th, 2009 at 12:23 pm
When I run all these numbers (generator efficiency, amount of battery at customer depletion, engine hp, car weight, hp required, etc) through my shadetree mechanic’s analysis, I keep coming up with the same conclusion. It’s going to be very difficult to get all this to work at all, much less work well. I just don’t see the volt performance in customer depletion mode getting a good grade. At best, maybe a D -. That’s just not going to go over well for $40 (or even $30) grand.
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May 4th, 2009 at 12:25 pm
@ #77 CorvetteGuy,
>> Las Vegas has 1 Camaro SS. [...snip...]
>>The bulk of the SS models seem to be in Texas.
>> I think us Californians are getting the short end of the stick.
No offense to Californians, but this may give you a taste of how EV enthusiasts feel whenever an EV model is announced or launched subject to “limited availability rollout.” Seems like those are always targeted to CA, NYC, Washington DC, etc.
Case-in-point: The Aptera. I think I would really love owning one! But I live in Wisconsin. Therefore, I’m screwed for the foreseeable future. We will not be getting them anytime soon. Oh sure, Tesla’s may be opening a Chicago dealership, but whoTF can afford a Tesla yet?
Cheer up though. At least (and I do hope for this, on your behalf) you will only have to wait a few more days or weeks for the Camaro SS to make its rounds.
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May 4th, 2009 at 12:31 pm
#89 Mike D
Who cares about the engine RPM being loud when you’re climbing a steep grade or demanding high performance?
——
The concern isn’t high NVH when under heavy load, the concern is high NVH at a stop light, or when breaking.. See #35 above, if the SOC is very low, from a long hill climb, and you crest the hill, and have to stop at a light, it’s not going to seem “normal” have have the ICE cranking at 4K RPM, to make up some of the deficit.. That’s not “pompous”, its just going to seem like a stuck throttle…
It’s all very circumstantial, depending on SOC when you started, speed up hill, SOC at top of hill, etc.. But the above is clearly a possibility… One that GM has recognized and seems to be working on, and not yet ready to show off the results just yet (aka it’s not done yet)…
I agree that this seems like something that should have been forseen about 2 years ago, but clearly, they are dealing with it now… I’m just sort of surprised they didn’t “limit” the mule test to avoid hills, or just control the circumstances under which the ICE would cut on.. It’s makes one think that they have a way to go yet…
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May 4th, 2009 at 12:32 pm
@88 Guyman
As much as OnStar has been talked about by GM Engineers/Designers etc w/the Volt, I dont know if you could order one w/out it. Would a “firmware” change be necessary for a small tweaks.. i dunno. The update could be dowloaded whenever.. and installed at the operators convenience.
On the display, I agree, I dont think you will have much control over it. Maybe just simple things like Analog vs. Digital display. Or colors.
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May 4th, 2009 at 12:37 pm
TEST
Why are my posts no coming through…..
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May 4th, 2009 at 12:38 pm
Finally!!!
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May 4th, 2009 at 12:40 pm
Thanks.. I had read previously the Cruze engine was 100hp normally aspirated and 140hp with turbo.. and then a 3rd version for the Volt at 25% less hp because its an atkinson cycle.
………………………………………
#87 carcus1 Says:
May 4th, 2009 at 12:14 pm
Not what you’re asking for but I’ll put the engine numbers up as a data point anyway. ( this is family 0 1.4 l GM)
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May 4th, 2009 at 12:42 pm
This could all be avoided if GM would just make BEV version Volt. There is a huge demand for a non ICE vehicle, just pull all the range entender junk out and give us a true EV. Build the car we want GM! You could still build a range extended version for the namby pamby range anxiety crowd. But a cheaper Volt-Lite would be a huge seller!
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May 4th, 2009 at 12:43 pm
@Herm 78
“wrong math.. the ice would have to provide 95hp if the genset was 75% efficient to generate 53kw of electricity.. and it is very possible 75% may be what it is at full output, hopefully up to 95% at 25kw output.. the generator will need liquid cooling for sure.
Does anyone have any real numbers on the generator and motor?”
You’re right, I used the wrong percentile.
Nobody knows anything on the Genset. I’ve been trying for months. All we know is what ICE is being used.
carcus1 – Here’s the specs on the UQM I am guessing they might be using mated to the ICE. Google for “UQM PowerPhase 75″
My posts keep getting “Not Posted”….lol
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May 4th, 2009 at 12:43 pm
Charlie H,
As someone who drives a Prius regularly, I can tell you that having the engine kind-of do its own thing (including shutting down and starting up) takes a little getting used to — but I got used to it after only a short time driving the car. I’d say that it’s about same amount of time that it takes for an experienced driver to learn the feel of a particular clutch in a manual transmission car. If you’re the kind of driver who can guess how long your car can coast on a particular stretch of road, predicting what the Prius drivetrain will do is fairly easy. I imagine that the experience of learning the Volt’s responses will be similar, even if though the circumstances under which the gasoline engine starts are likely to be drastically different.
What’s weird is that neither myself nor my girlfriend like the driving-experience provided conventional automatic transmission cars — even though it’s the most popular driving paradigm in the western hemisphere. I don’t like it because I’ve driven manual-transmission vehicles for 95% of my personal miles, and I get annoyed that the automatic transmission computer doesn’t anticipate the road the way that I do. On the other hand, my girlfriend, who has driven the Prius almost exclusively for 4 years, she finds any abrupt change in engine speed to be unnatural. When we drive a rental car, she’ll sometimes wonder aloud if there’s a problem during the first couple of automatic shifts. Our reasons may be different, but both of us are likely to consider the driving-experience a conventional automatic transmission to be inferior during a test-drive.
The bottom line: you get used to what you drive, but change is easy if you want to learn a new vehicle.
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May 4th, 2009 at 12:46 pm
If the car is not muted then GM need Toyotas help.
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May 4th, 2009 at 12:49 pm
#87 carcus1 says
1.4 L Straight-4 (1364 cc): 73.4 mm (2.89 in) bore, 80.6 mm (3.2 in) stroke, 10.5:1 compression, 90 hp (66 kW) @ 5600 rpm, 125 N·m (92 lb·ft) @ 4000 rpm.
http://en.wikipedia.org/wiki/GM_Family_0_engine
Note: that 90 hp is at 5600 rpm. Pretty sure GM’s not going to run the volts engine at 5600 rpm in any circumstance.
———————–
That really illustrates the point I was trying to make. The 1.4L Family 0 engine in the Volt (and its future upgrade in 2011) have ’sweet spots’ very high in the band.
GM wants the car to go 40 miles on battery, and then have it be a virtual brick (other than some trickle charging) under the car until the customer recharges it. ie) no power usage after it has done its 40 AER That way, it is easier to hit the 10/100 standard…and they don’t go into their self-imposed 30% reserve anymore often than completely necessary.
Problem is, this is now a 3,500 pound car, if you go up a hill or accelerate, it needs every drop that 4 cyclinder can put out to even remotely be adequate. So whenever the driver, mashes the gas, that engine is going to spool up into a high, monotonous, RPM program.
Even then, I think GM is finding, it needs more juice…so the battery is ‘returning from the dead’ to assist in these scenarios, but how is the system handling going from peak ICE output to instantaneous gobs of power from the battery? Maybe not so smooth.
Side note:
I still don’t see how we are getting anywhere near to 50MPG. The Cruze goes on sale in the UK in like 10 weeks, and has been rated at 35MPG (US gallon conversion) for the road.
I really can’t see getting a 50% improvement on these numbers, as well as making up that difference in a almost 700lb heavier Volt (2,838 vs 3,500), especially considering what the 4 banger is expected to do, namely push around (and accelerate) a 3,500 pound vehicle. Right now, (and even with the ‘better tech’), I think I would be surprised to see it just be able to break even with it’s Cruze cousin at 35MPG.
/personally I would be fine with 35MPG, I really just want the EV part, but w/e, still a issue because a lot of other people care about it
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May 4th, 2009 at 1:15 pm
#4 Rashiid Amul Says, “When I took my lone ride in the Prius, it was extremely obvious the ICE turned on…”
That was also my experience when my friend took me for a ride in his Prius. However, I test drove a Ford Fusion hybrid this weekend, and there were many times when I couldn’t tell whether the engine was running or not! That is a very well integrated hybrid and I’ll probably buy one. I’d like to hold out for the Volt, but it will probably be 2012 before I’ll be able to find one available at a local dealer show room.
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May 4th, 2009 at 1:19 pm
CaptJack @ 98,
Thanks,
That could be a possibility for the traction motor/braking generator. I don’t think we’ve heard much on the generator (hooked up to the ICE), other than it’s rated at 53kw. Maybe GM’s building/ spec’ing out their own?
p.s. I’ve always assumed the generator is hooked up to the ICE at just one speed. (i.e. there’s not a transmission/ cvt that allows the ICE and generator to vary speeds relative to each other?)
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May 4th, 2009 at 1:20 pm
@carcus1 87
1.4 L Straight-4 (1364 cc): 73.4 mm (2.89 in) bore, 80.6 mm (3.2 in) stroke, 10.5:1 compression, 90 hp (66 kW) @ 5600 rpm, 125 N·m (92 lb·ft) @ 4000 rpm.
Here’s something to think about. If the ICE is is delivering electricity for the motor and the batt pack is delivering electricity to the motor, then by principle of how an AC induction motor works, the batt pack is also delivering electricity to the AC Induction Genset for Stator “Excitation” (Create a magnetic field/flux electrically for the coper coils to cross). So for all intents and purposes, during “Charge Sustaining Mode” the batt pack is delivering electricity to both the Genset AND the electric motor/controller.
Does that sound right? Doesn’t sound efficient to me.
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May 4th, 2009 at 1:22 pm
A few comments:
I have been part of designing a dynamic (passively controled, IE software/circuity only) reaction system. The issue that GM may be having could have nothing to do with power issues OR noise issues.
Simply put, you as the driver know what your maximum power (top speed/slope) requirements will be and the length of time you will require them. The car has no idea. Furthermore, different drivers approach the same situation very differently. For example, I will ramp up my speed 5-10mph as I see a high approaching, whereas many other drivers may attempt stay completely constant.
The challenge for GM is to create a response system that delievers the right amount of power at the right time for the most common situations driven by multiple different drivers.
Some examples of what can go wrong:
“Overdrive” in LCD panel technology- LCD panels rely on twisting polerazation of different layers to change the color of an individual pixel. The twisting is done by changing an applied voltage with the rate of twist being determined by the difference between current state and the applied voltage. Since some panel naturally have a low rate of twist, some smart people decided to create a response curve that applies a very large initial change of voltage then applies the correct voltage… essentially twitching the color change very fast to close to the correct color, then allowing a slower change through the shades for an overall faster change (and theoricatically a much faster percieved change). Furthermore, they decided to track color changes across the LCD panel to predict the future state of a pixel color to attempt to start changing the pixel -early- to make the change even faster.
They ran into problems (in released products) where the twitch color change would push the color -past- the destination point… creates an unpleasant effect for many shades of color. “Ghosting” where faint traces of image can be seen in multiple places. And lag between creating input and displaying input due to the “prediction” software.
The Volt may have a similiar issue. Take the situation where you are passing on the highway after having been forced to slow down from 60 mph to 50 mph. The “normal” driving response is to slam on the gas until you hit 70 mph and then coast past the car to resume 60 mph driving. This may cause a few different reactions based on battery SOC level:
#1. No change, No Generator at all
#2. Medium RPM generator start
#3. Move from low RPM to High RPM.
Situation 1 is no issue. But situation 2 and 3 can be tricky. In sitation 2, the small time of significantly higher load may cause the generator to start with very high SOC level. Thus causing the generator to click off again after a few second (as you coast down from 70 mph to 60 mph) just to have it start again within a minute or two. This would make it seem like the Volt was confused and would use significant gas when none was really needed.
Situation #3 could also be an issue if a significant feathering was introduced to avoid sutation #2. The ICE could reaction like an old fashioned Turbo/Lag…. except your acceleration to 70mph, THEN load engine until your at 60mph and THEN quiet engine. Essetinally the reverse of standard operation.
It seems to me the only way to attempt to balance this out is to perform real-world testing by a variety of drivers using multiple different control paths. Since this is a “software” issue, final production volts can be built before the software is 100% ready. I would image GM is using the Cruze-Volts to build a large database of response requirements in real-world sitauations….
Essentially, I see the refusal to allow people to test non-production ready software as reasonable, the testing cycle for the software is just starting.
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May 4th, 2009 at 1:23 pm
Sometimes I hate these posts where every one and his brother, plus their step sisters and their cousins too, assume a conclusion based on non experienced, untested, unpublished, non-sourced total speculation.
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May 4th, 2009 at 1:24 pm
#52 carcus1 Says: Bottom line here is you’ve got a 3500ish lb. car and a 90ish horsepower engine.
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No. The Volt’s max engine output is much lower, around 70ish horsepower. This is consistent with a 1.4L Atkinson cycle engine. As a comparison, look at the Prius 1.5L 76hp engine, also Atkinson cycle. Both the Prius and Volt can use the lower output higher efficiency Atkinson cam tunings because they both have a battery to provide peak power.
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May 4th, 2009 at 1:25 pm
@cracus1 103
“That could be a possibility for the traction motor/braking generator. I don’t think we’ve heard much on the generator, other than it’s rated at 53kw. Maybe GM’s building/ spec.ing out their own?”
True. Someone did post in past that it “may” be an AC Induction motor. Which is an adequate choice because of it’s compactness and weight compared to a PMG/PMA.
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May 4th, 2009 at 1:27 pm
#87 carcus1 Says: 1.4 L Straight-4 (1364 cc): 73.4 mm (2.89 in) bore, 80.6 mm (3.2 in) stroke, 10.5:1 compression, 90 hp (66 kW) @ 5600 rpm, 125 N·m (92 lb·ft) @ 4000 rpm.
http://en.wikipedia.org/wiki/GM_Family_0_engine
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These figures are all for the Otto cam tunings, not the Atkinson cam tunings used in most hybrids. Apples and oranges.
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May 4th, 2009 at 1:27 pm
#88 GuyMan says, “…As for UI skins, that ain’t gonna happen either (unless they are provided by GM), why would they, it just opens up the software to more folks, and more potential problems, just to change the look/feel of the interface …”
Why would they?! To make the car more desirable, of course. People want to customize. This is one way to distinguish the volt from its competition. By focusing on the negative, you are encouraging GM to fall into their old ways and miss a marketing opportunity.
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May 4th, 2009 at 1:32 pm
101 Statik
I think I would be surprised to see it just be able to break even with it’s Cruze cousin at 35MPG.
==========
How much energy do you get from renerative braking? What about constant RPMs in “sweet spots”? I dont know what kind of percentages these translate into.. just thought i’d throw at least those 2 out there.
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May 4th, 2009 at 1:34 pm
I still think GM should sell a non Genset version. Just ommit the Genset and all the other required hardware for it. This will guarantee me the 40AER beacuse the car will be lighter by at least 500lbs or more and increase the life of the batt pack because I won’t be lugging around the the Genset 100% of the time “Just In Case”.
ICE RPM and vibration solved.
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May 4th, 2009 at 1:35 pm
I’m with Rashiid and the others that think this is no big deal. The Volt is not a car you want if you’re constantly driving long distances. The Smart is about as horrible a ride as you can have and I’ve known people (who should know better) drive it from Phoenix to San Diego. The Volt can’t be any worse than that.
GM needs to figure out that the customers for this car will cut them some slack on things like this. EVs are not going to be able to compete with ICEs on every attribute. They just do things that ICEs can’t – run without gas. You either want that or you don’t. (This is how every new technology wins — by winning on the basis of an attribute irrelevant to the old technology. The first digital cameras weren’t exactly competitors for an SLR, but they had the advantage of not needing film and having the pictures instantly available. Now you can’t buy a film SLR).
#86 Mark M says “These numbers seem to be taylor made to promote the Volt”
Interesting observation. You’ve got a horse before the cart issue. GM started with these numbers and some other (better) numbers as well. It used the numbers when designing the Volt. So it’s not that the numbers are manipulated to promote the Volt, it’s that the Volt is designed to fit the numbers.
#15 charlie h – Thanks for decoding NVH.
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May 4th, 2009 at 1:36 pm
#108 CaptJackSparrow Says: I don’t think we’ve heard much on the generator, other than it’s rated at 53kw. Maybe GM’s building/ spec.ing out their own?”
True. Someone did post in past that it “may” be an AC Induction motor.
————————————————————————————–
The Volt’s electric motor is induction. This comes directly from GM.
There is little info on the generator, other than it’s rated at 53kw, so we don’t know if this is an induction or permanent magnet type generator. Given that 53kW is pretty big, I would assume induction, but GM has not verified that.
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May 4th, 2009 at 1:38 pm
#101
statik Says:
May 4th, 2009 at 12:49 pm
I still don’t see how we are getting anywhere near to 50MPG. The Cruze goes on sale in the UK in like 10 weeks, and has been rated at 35MPG (US gallon conversion) for the road.
I really can’t see getting a 50% improvement on these numbers, as well as making up that difference in a almost 700lb heavier Volt (2,838 vs 3,500), especially considering what the 4 banger is expected to do, namely push around (and accelerate) a 3,500 pound vehicle. Right now, (and even with the ‘better tech’), I think I would be surprised to see it just be able to break even with it’s Cruze cousin at 35MPG.
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Huh? I think your being unreasonably pessimistic
I haven’t seen any numbers for the Cruze 1.4L turbo engine posted yet… I have seen a 1.6L engine posted at 43 US mpg (Highway which is more important than the combined number of 35 for City/Highway). Yes, thats probably more like 35 US mpg when tested by the EPA. I look at the Corrola with a 1.8 L engine with 35 US mpg highway compared to the Prius at 45 US mpg with its 1.5 L atkinsons cycle engine.
It looks like it would be tough to get to 50 US mpg, but the Cruze data suggests numbers north of 40–>45 are still possible.
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May 4th, 2009 at 1:38 pm
105 Steel
I’m sure there will be a significant deadband in there where you won’t have a constant on/off of the engine.
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May 4th, 2009 at 1:42 pm
#103 carcus1 Says: p.s. I’ve always assumed the generator is hooked up to the ICE at just one speed. (i.e. there’s not a transmission/ cvt that allows the ICE and generator to vary speeds relative to each other?)
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That is correct. The Volt’s generator is mounted to the gas engine’s drive shaft. There are no gears.
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May 4th, 2009 at 1:42 pm
#107 Dave G.,
” The Volt’s max engine output is much lower, around 70ish horsepower. This is consistent with a 1.4L Atkinson cycle engine.”
_____________
Ok Dave. So you’re saying the Volt will use a 1.4L Atkinson cycle engine with a max hp of 70.
Have you got a source on that?
P.S. you can’t just “tune” your otto engine into an atkinson
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May 4th, 2009 at 1:46 pm
I don’t really know what all the fuss is about. The range extender noise can be mitigated somewhat, but of course it will make noise. I doubt it will be a deal-breaker for consumers if the Volt is merely somewhat quieter than regular cars after they travel 40 miles. This won’t be the majority of operation and I doubt it will be that unpleasant, if at all.
Although I bet the GM engineers are trying to make even ICE mode ridiculously quiet regardless, just to keep the Volt “silent driving” claims alive.
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May 4th, 2009 at 1:48 pm
#115 Steel Says: I look at the Corolla with a 1.8 L engine with 35 US mpg highway compared to the Prius at 45 US mpg with its 1.5 L Atkinson cycle engine.
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The new Prius uses a 1.8L engine and it gets 50MPG.
I bet Toyota uses the same engine for both the Corolla and the Prius, and the only difference is the camshaft tuning (Atkinson vs. Otto). The camshaft tuning seems to matter more than the size of the engine. An Atkinson camshaft significantly lowers peak power and significantly increases efficiency.
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May 4th, 2009 at 1:48 pm
#111 k-dawg Says:
….in response to: #101 Statik, I think I would be surprised to see it just be able to break even with it’s Cruze cousin at 35MPG.
“How much energy do you get from renerative braking? What about constant RPMs in “sweet spots”? I dont know what kind of percentages these translate into.. just thought i’d throw at least those 2 out there.”
=========
No clue at all…just thinking out loud. We have a double digit (not sure exactly where) 4 banger pulling a 3,500 pound car with new tech and regen braking. So many variables. Will be intereresting to see what kind of numbers it pulls in for sure…and what performance we will see.
/shrug
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#106 Jeffre says:
Sometimes I hate these posts where every one and his brother, plus their step sisters and their cousins too, assume a conclusion based on non experienced, untested, unpublished, non-sourced total speculation.
————–
Heeh, that is just about every post here. Every post seems to bring up new questions. Fact is, after 2+ years we know next to nothing about any ‘tested, published, sourced’ specs so far, even GM doesn’t know most of these things until they get a working prototype…but speculating is a interesting way to pass the time.
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May 4th, 2009 at 1:51 pm
#118 carcus1 Says: Ok Dave. So you’re saying the Volt will use a 1.4L Atkinson cycle engine with a max hp of 70. Have you got a source on that?
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No, GM has not confirmed this. But looking at other Atkinson cycle engines, this makes sense. For example, the Prius 1.5L engine is 76hp:
http://www.toyota.com/prius-hybrid/specs.html
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May 4th, 2009 at 1:55 pm
#118 carcus1 Says: P.S. you can’t just “tune” your otto engine into an atkinson
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I thought it was just the shape of the camshaft. Am I missing something here?
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May 4th, 2009 at 1:57 pm
#116 Kdawg
105 Steel
I’m sure there will be a significant deadband in there where you won’t have a constant on/off of the engine.
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But see, thats may be part of the problem. The size of the deadband and the general speed of response can lead to very strange results. Whether or not there is a “deadband”, the instaneous power draw could be a real issue for the volt.
I guess, I will state again, the people making the assumption that the control circuit/program for the ICE is just “kick on and produce X power” is a simplistic view. In reality, the control software will be much more complex and need significant real-world testing before you let a member of the press “play” with it. At this point, I don’t see it as an issue since there is still not even one 100% production volt to get the results “right”. I would even expect the control software that works the best for the Malibu-Volts, the Cruze-Volts, and the real volts to be different.
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May 4th, 2009 at 2:00 pm
#120 DaveG
—–
The Prius and (US) Corolla wieght pretty much the same. I would be shocked if the Volt gets the same increase from moving to an Atkins cycle engine that the Corolla–>Prius gets because the extra wieght of the Volt (at least 500lbs) will take a significant toll. But to say that it will take the entire change seems to be… unrealistically pessimistic.
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May 4th, 2009 at 2:02 pm
Just something to consider.
GM doesn’t want to kill the battery, and will perhaps warranty it for 10years/150,000 miles. This means the battery must stay in its sweet spot, approximately 30 to 80% SOC. Once at its depleted condition, the ICE provides average vehicle power and maintains the battery at or near the 30% SOC.
If the Volt’s “buffer” zone is truly from 25 to 35% of battery capacity, this represents 10% of the total battery capacity or 1.6 kWh. The Volt’s traction motor is rated at 111 kW. So for full power accelerations and hill climbing, the power in the “buffer” has 1.6*3600/111 or 52 seconds worth of energy.
This isn’t a lot for people in hilly terrain or the teenager doing drag races. Granted, with the genset at rated power, it provides ~50 kW, while the battery pack provides the other 61 kW, however, you may not always start your drag racing with the buffer at 35% SOC either.
As mentioned previously, there are likely hundreds of scenarios that must be considered to make the Volt’s driving experience as seemless as possible ( I noted in many of the mule test drives that GM is striving to make the Volt driving experience similar to that of a conventional car).
My guess is that GM has a great deal of tuning and testing to complete before they let the press put this car through the paces with the Volt in charge sustaining mode.
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May 4th, 2009 at 2:04 pm
#124 Steel Says: Whether or not there is a “deadband”, the instantaneous power draw could be a real issue for the volt.
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I’m not sure I’m following you here.
When the Volt’s gas engine is running, the battery pack still handles instantaneous power draw.
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May 4th, 2009 at 2:08 pm
N Riley @58, yes it will be nice when someone gets to actually drive the Volt in charge sustaining mode. Two ideas offered in this thread sound reasonable to me. One is to “enable” feather up to mid or high power by current traction motor load, so if the load is reduced by coasting to a stop, even with the SOC below the mid or high power setpoint, the ICE would feather back to its low power setting. This would be something below 8 KW load.
My car leaves its headlights on when I get out and walk away and it is slightly unnerving, to trust the timer which shuts them off after 30 seconds or so. I think we are going to have to get used to having the ICE run at a pretty good clip, around 2000 RPM, when we stop the car for a minute or two in charge sustaining mode. I am ready to embrace the new paradigm.
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May 4th, 2009 at 2:10 pm
Simple napkin calcs
Volt power usage
8 Kwh- 40 miles
1 Kwh – 5 miles
Modern diesel genset
50Kw peak output – 4.2 gal/h of diesel fuel
11.9 kWh/gal
59.5 mpg in gen mode on diesel
Gas is 30% less efficient
41 mpg in gen mode on regular gas under the ideal conditions.
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May 4th, 2009 at 2:18 pm
#127 Dave G.
———————
I don’t mean in a performance limiting way. I mean more in terms of control limiting way.
The Volt is going to have to “predict” your future power requirements based on your current usage. If they miss with the software, it should be possible to literially create 100% reverse reaction from the Volt. IE high rpm load with foot not on gas and low rpm load with Volt floored. This would not be a “desirable” result even if the Volt performes correctly and with reasonable efficiency.
From what I understand, the goal is to keep the Volt’s battery between 25% and 35% SOC. 10% of the 16kWh is 1.6 kWh, which as another poster noted is only 52 seconds of 111 kW power…
I think a simpler answer might just have a “boost” measure display in the car that reacts to the SOC remaining until hard shut-off of battery power (whatever that is 5-10-15% or something) with a “target” bar. That way a driver will understand why thier car may be running high RPM on a flat section/cruizing and low RPM on a hill/pass manuever.
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May 4th, 2009 at 2:20 pm
Re Lyle and Statik being able to stay “mum” after a test drive, we KNOW Lyle can. He also gets a lot of practice with confidentiality being a physician. I think statik would do everything in his power to keep it under wraps too. Right up to the time his head exploded (g)
Just joshing Statik, I know you could do it. You may set a new record for length of post after the wraps came off though.
Be well,
Tag
LJGTVWOTR!!! ********NPNS
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May 4th, 2009 at 2:25 pm
#126 BillR,
As I understand it, wandering outside of the battery’s sweet spot occasionally doesn’t really affect longevity. It’s only when you do it constantly that it becomes an issue.
In the Pikes Peak scenario article:
http://gm-volt.com/2008/09/02/the-pikes-peak-question-chevy-volt-and-the-infinite-hill/
GM said driving 80 miles per hour up a 6% grade would drain 10-15 kW from the battery. This seems consistent with calculations of others here on this forum (nasaman IIRC), that say the Volt will go around 60 miles per hour up a 6% grade on ICE power alone (no battery power at all).
So let’s assume the ICE turns on on at 30% charge and the Volt’s battery stops providing power at 10% charge. That leaves 20% of the total 16kWh for peak power, or 3.2kWh. GM says going 80 MPH up a 6% grade would draw 10-15 kW from the battery. Let’s be conservative and call it 15kW. 3.2kWh / 15kW = 0.27 hours, or around 13 minutes. At 80 MPH, that’s 17 miles.
So to run out of battery peak power, you would have to drive a constant 80 miles per hour, without ever slowing down, up a very steep and constant 6% grade, without any curves to slow you down, and without any level or downhill spots to recharge the battery, and you would have to keep that constant 80 MPH uphill speed for 17 miles straight.
I don’t know of a road that would allow any sane person to do this. All the mountain passes I’ve driven have curves that force you to slow down, and no roads go constantly uphill for 17 miles without any level of downhill spots. So it looks like any reasonable driver will never hit this limit.
As for wearing out the battery in this scenario, again it’s only when you do it constantly that it becomes an issue. So how many people’s daily commutes involve 17 mile 6% grades? And of those people, how many routinely drive a steady 80 MPH up those steep hills? In the end, I believe GM will have to replace very few battery packs under warranty due to this particular issue.
As for drag racing and such, most of this doesn’t last anywhere near 17 miles, so while the instantaneous power draw is high, the energy drained from the battery is relatively low.
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May 4th, 2009 at 2:36 pm
#125 Steel Says: The Prius and (US) Corolla weight pretty much the same. I would be shocked if the Volt gets the same increase from moving to an Atkins cycle engine that the Corolla–>Prius gets because the extra weight of the Volt (at least 500lbs) will take a significant toll.
————————————————————————————–
Testing has shown weight to be less of an efficiency factor than most people think.
For a normal car, weight is a big deal. But for an EREV or strong hybrid, the extra power required to accelerate is mostly recovered in regenerative braking. Weight does affect tire rolling resistance, which decreases efficiency, but not that much.
Note that the Atkinson cycle engine doesn’t really work well in a normal car because you need the peak power anyway. But in an EREV or hybrid, the battery provides the peak power, so the engine only has to supply average power.
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May 4th, 2009 at 2:42 pm
#122 , 123 Dave G.
Not all hybrids use Atkinson cycle engines. The new insight does not. I would presume Honda didn’t because they need all the HP they can get out of the little 1.3. and only one small electric motor . I don’t know that an Atkinson cycle engine would even be a good choice for running the volt’s generator. Increased efficiency but decreased torque may not be advantageous in this scenario. It certainly wouldn’t help in any hill climb scenario.
Your thought train keeps going down the “there’s loads and loads of extra battery power available” track when in range depletion mode. But we’ve never seen anything like that coming from GM. And as we covered in earlier threads, if you open up that customer depletion window you’re going to be sacrificing battery cycles.
I’ve never seen any credible source say GM was going to convert the 1.4 l engine over to Atkinson, and if they did, I’m sure there’s going to be a lot more involved than just switching a camshaft.
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May 4th, 2009 at 2:43 pm
Dave G #133,
good point on the Atkinson cycle engine. thanks!
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May 4th, 2009 at 2:54 pm
Just glue a misaligned blender to the vehicle, that ramps up whenever the accelerator pedal is pressed, to emulate typical ICE NVH, regardless of less than 40 miles or not.
It’s deeply ironic that what’s holding GM back now is that they feel they need to engineer something that makes the Volt imitate current, inferior ICE operation to make the driving experience transition from full gassers invisible for the thumbsuckers.
Why not just do what the Prius did over a decade ago and let the driver experience reality, with some reasonable muffling, and get the thing out already? Frankly, any difference from full gasser ICE ought to be an additional part of any price difference from a full gasser. If I wanted a vehicle that pretended to be a lame full gasser, I’d just buy a 1985 Yugo.
In fact, If I were GM I’d provide journalists with a used Yugo, or some similarly performing and quality vehicle, for side by side drive test comparisons of the Volt so they have a full gasser there for direct reference with the Volt post 40 mile experience.
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May 4th, 2009 at 2:55 pm
#114 Dave G
“The Volt’s electric motor is induction. This comes directly from GM.”
——————————
This Scientific American article from 2 years ago states:
“Drive power for the Volt will come from a 136-kilowatt- (or 160-horsepower-) at-peak permanent-magnet electric motor that produces 320 newton-meters of torque, Zielinsky explains.”
http://www.scientificamerican.com/article.cfm?id=gm-resurrects-its-electri
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May 4th, 2009 at 2:59 pm
128 Van
Your mention of the headlights made me think about when i finish driving my Volt and its at 29% SOC, and I put it in park and turn it “off”….. will the engine continue to run for a bit to get it back up to 30%?
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May 4th, 2009 at 3:00 pm
#133 DaveG
——————-
Some back of the enevolope calculations.
Most tires have between .007 and .014 Rolling Resistance Coefficient. Lets assume the Volt/Cruise go with a reasonably durable/cost tire— Michelin SYMMETRY P225/60R16 which has a rolling resistance of .0065 and a cost of ~100 dollar per tire and 65,000 mile warranty for tire wear.
500 lbs of gravity force will result in 3.25 lbs of extra rolling resistance or 14.43 N of force. Traveling over 1 meter will require an additional 14.43 Joules of Energy… so additionally consume 14.43 Joules per meter. Or 23,200 Joules per Mile —> .0064 kWh per Mile. A Volt is projected to consume around .2 kWh per Mile (8kWh/40), but a Cruze Wieght Volt would be able to travel 41.3 mph or have approx 3.25% better fuel economy from the lower wieght, which is a best case senario for reduction of fuel economy. In the real world, we should expect more of a 5%+ change in fuel economy going from a “Cruize-wieght” volt to a actual volt wieght
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May 4th, 2009 at 3:02 pm
@ carcus 134
well, then I want the turbo diesel version. Better performance, efficiency and mileage, small cost difference if done right (call VW if need be?), and it’ll really weird out the folks in Alma, when your Volt figures out from your GPS that you’re going over Hoosier Pass and fires up the combustion engine but good in advance while you’re doing 20 mph through the mountain end of town. All good.
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May 4th, 2009 at 3:11 pm
Oh boy, #132, 133.
Dave G. is on a big misinformation cut and paste campaign once again.
I’m just going to hit 2 of them.
1. Weight matters.
2. GM is NOT going to let that battery go down to 10%SOC. If you hit something close to 0% you will ruin the pack. Going to 10% would be dangerous enough charging in a controlled static environment (i.e. your garage where there is no load, temperature is constant, no vibration, your using constant grid power for a source). Put it out on a hilly highway with the genset running , changing speeds, changing temperatures etc. . .and there is no way in H. E. double toothpick they are going to risk running down to 10%.
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May 4th, 2009 at 3:11 pm
I am fairly certain the Volt will be butter smooth in gen mode, once they decide to put in a small V8 or V12.
Just kidding, of course. I simply don’t care what program GM uses to control the ICE. The technology is what is important. The “polish” will come later.
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May 4th, 2009 at 3:22 pm
@ BillR 137
from Scientific American:
“Drive power for the Volt will come from a 136-kilowatt- (or 160-horsepower-) at-peak permanent-magnet electric motor that produces 320 newton-meters of torque, Zielinsky explains.”
So sad. That’s adequate for a 1,100 pound vehicle in my book. Give the Volt some real power, please, please. The driver can always put it in eco mode. Don’t skimp on the Volt’s heart and soul. Or at least have a gen II power version available at a premium for us power hungry meatheads who know what electric drive is capable of.
Napkin work: 320 Nm = 236.01984000000002 lb-ft of torque. meh. Not impressed.
American muscle cars are NOT dead. They’re just going to be electric from now on. Just to be clear, my preference would be for the Volt to have 750 lb-ft of electric drive torque, when the similar weight Dodge Viper has 510 to 760 lb-ft. Someone talk me down?
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May 4th, 2009 at 3:23 pm
#140
Yeah, buddy!
Slap on your GM Volt Diesel Power ball cap and keep on truckin! Plus you’d get a big wave from all the train engineers along the way.
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May 4th, 2009 at 3:28 pm
A long time ago, didn’t GM talk about the Volt knowing the elevations as you are traveling along? I have a dim recollection of that. If the Volt knows your route and ‘knows ‘ the elevations then I guess it could get pretty darn clever about how much it needs to run the generator. They also said they want you to get back to your garage(or other charging point) at 30% of battery to maximize the savings from charging off the grid. Oh but wait, you can’t do that in the daytime and the greenies and cap and traders are going to ’skyrocket’ electric rates, so GM just give yourself a break and charge it back up to 80%, then cut it off.
Wonder if they’ll input the elevations or record them?
GM sure is doing one hell of a good job with this project, most interesting.
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May 4th, 2009 at 3:28 pm
@BillR 137
#114 Dave G
“The Volt’s electric motor is induction. This comes directly from GM.”
——————————
This Scientific American article from 2 years ago states:
“Drive power for the Volt will come from a 136-kilowatt- (or 160-horsepower-) at-peak permanent-magnet electric motor that produces 320 newton-meters of torque, Zielinsky explains.”
———————————————
Just like the original body design of the Volt. Things changed.
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May 4th, 2009 at 3:28 pm
#86 Where are you getting these numbers you post repeatedly?
These numbers seem to be taylor made to promote the Volt, not actual real world numbers I found on a quick google search.
_______________________
He admitted to making them up. The hope was they would later be confirmed with real-world data, hence SMTD. We are still waiting…
Of course, the numbers are “typical” anyway even if the distances were, simply because people don’t actually drive in ideal conditions. In real-world, they use the Heater & A/C and drive very much in a behavior not supportive of efficiency.
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May 4th, 2009 at 3:37 pm
If I’m traveling 280 miles home to see my Momma for Mother’s day, GM, just keep that charger running on high til we’re back to 80%, lighten the load by burning gas, come back on at 30% again, and etc to get me home to Momma’s house.
I don’t wanna make any noise in the driveway, so make sure the genset is done with it’s work about a mile away.
Computers are wonderful. Why don’t you give me a genset button? I’d like to have control of it – you can override at 30 and 80.
Also, I’d like to turn off the genset when my tradional Irish music from Tina Mulrooney is playing. Try it you’ll like it.
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May 4th, 2009 at 3:43 pm
I think I’ve read enough of the post here to make the following observation. I just drove a prius this weekend so I have that added experience to add.
It seems to me that the largest problem will be that the battery will only accept a charge at a rate of 2KWH. At maximum power, the genset might produce 50KW. It seems the problem is as follows:
1. You are trailing a semi and need to pass. Battery is a Customer Depletion Point.
2. You step on the accelerator, genset increases to maximum output, all that power is going to the wheels.
3. You pass the semi, and quickly reduce speed by lifting off the gas.
4. Now What? You have the Genset at maximum capacity, but all the excess energy has knowhere to go. Battery can only accept a charge a certain rate. Wheels don’t need the power, so does the genset go back down to a much lower level of output.
This can be summed up as follows. The car does not know what the drive will do next.
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May 4th, 2009 at 3:47 pm
#149 Peter M.
Good point. I do not recall this scenario having been discussed.
Maybe the volt needs a “hybrid battery” (super cap along with the Li-ion) to absorb surges.
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May 4th, 2009 at 3:50 pm
Why do you people try? Just listen and be informed.
You can’t have no BEV carcus1, nor you Cap’n Jack, nor you Statik Elektrik,nor any of all ya’ll malefactors think you want one.
Took a sail with Cap’n Jack Morgan at me daughter’s wedding this weekend past and it’s made me ruder than usual.
Peace be with you.
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May 4th, 2009 at 3:54 pm
Yes if the gen comes on to run and you are not near a terminal, you might need to build a reserve. I think they are doing all this.
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May 4th, 2009 at 3:54 pm
@Peter M 149
3. You pass the semi, and quickly reduce speed by lifting off the gas.
4. Now What? You have the Genset at maximum capacity, but all the excess energy has knowhere to go. Battery can only accept a charge a certain rate. Wheels don’t need the power, so does the genset go back down to a much lower level of output.
A couple things first before I try and answer.
First, the battery pack is rated at 400VDC @40AH. This equals 1C
Second, runnigh high rpm doesn’t mean it’s running hard.
Now, in this scenario when you finish passing the Semi, your ICE is racing at a high RPM. You associate this with high power generation. You are somewhat correct in that the batt pack will only absorb 1C of charge so what happens to the rest? Nothing. The ICE will just race at a high RPM but will use less petrol to maintain it because the batt pack can only absorb 1C of power generated. The less power required (throttle down) the ICE will only feel less effect of Lenz Law (magnetic resistance during power generation).
Sure the ICE will be racing but there’s a difference between running hard in high RPM and running medium/easy in high RPM. In the scenario above, you will only be running hard high RPM for the duration of the passing of the Semi.
Make sense?
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May 4th, 2009 at 3:58 pm
#153 Capt Jack,
Will it sound like when the welder’s working off the portable rig on the back of his truck?
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May 4th, 2009 at 4:06 pm
K-dwg @ 138, I doubt it. I expect if you “shut-off” the Volt, the ICE will “feather down and off” so you do not operate the engine in the garage.
This would also maximize the amount of power you resupply from the plug, from the shutoff level, even if below 25% back up to 85% SOC.
And again, I am merely speculating as to what seems sound in the absence of GM explaining the programming goals, or allowing someone to evaluate the Volt’s performance in charging sustaining mode.
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May 4th, 2009 at 4:06 pm
@carcus1 150
“#149 Peter M.
Good point. I do not recall this scenario having been discussed.
Maybe the volt needs a “hybrid battery” (super cap along with the Li-ion) to absorb surges.”
I think the omission of an ultracap is a big design flaw. But I think I know why they did it. Ultracaps are expensive and because they designed the volt to operate at 400VDC, the Ultracap package would have to be huge and “Cost Prohibitive”. Just look up Maxwell Ultracaps. To achieve 426.6VDC for a string of ultracaps you would need 158 caps in series and if you used their largest 3000F cap you would only get 18.98F. Was it a good thing they ommited this? Cost wise, sure. Technologically speaking though the benefits of sucking up every juice from brake regen and being able to spit the same juice out faster than the batt pack to me outweighs it because they could’ve went for a smaller bat pack and it would increase the life of your batt pack. The ultracaps are great stress buffers. Those boom boom cars you hear down the neigborhood roads, chances are they have some 1-4farad caps to “Harden” the voltage source for their subwoofer amps.
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May 4th, 2009 at 4:09 pm
@ 154
Will it sound like when the welder’s working off the portable rig on the back of his truck?
I dunno man. The freeway noise and wind would be drowning most of the welders noise from outside the cabin….
lol.
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May 4th, 2009 at 4:21 pm
Genset Quietlearn.
One of the great things that software does for us everyday is that it constantly learns the best ways to run your vehicle. The voltec vehicles will not be an exception. With the 25 to 30 processors or subprocessors in many of today’s new vehicles, many of these constantly adjust for a large number of desired results.
Some folks would want a very loudly tuned exhaust noise to announce that “they have arrived” (at school). Some would want as complete a “quiet” as is possible at all times. Some would want a slight resemblance to the power curve indications that are present in the vehicle they currently drive. Your comments in this thread are helping GM to think in these terms, perhaps even for you to soft-select these sorts of characteristics in, say, a “sporty” version, or, more quiet in a luxury version of Voltec.
“Quiet learn” would be really easy to do for an anticipated drive up that long hill to pass a few semi’s, simply by commanding the Genset to “learn” the running characteristics to anticipate that climb the first time you do it. Cellphone towers broadcast location signals, and, the coordinates of the roadways for high torque demand can signal the Genset to up-charge the battery array a few minutes in advance at the lowered power levels, so that the highest power level outputs may not be as needed (and the peak wear patterns avoided).
Also, having an optional GM “software toolbox” of different selectable software subroutines for these characteristics in the form of an encrypted GM jump-drive to plug into the OBD2 connector, would give the “sports car” enthusiast something “custom” and “optional” to do. (In addition to being a backup reprogram repair tool to be owned by the owner).
Dan Petit Austin TX.
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May 4th, 2009 at 4:45 pm
In my view they have to have different config /optimized engine for EREV because
1) they don’t want pistons to avoid vibrations – may be rotary or turbine config
2) They want an optimized (high efficiency ) engine for driving the magnets ( high efficiency in generating the power etc) – The EV1 series hybrid was using the Williams Gas Turbine Power Unit uses a single-shaft, recuperated gas turbine coupled directly to a high-speed permanent-magnet AC generator.
3) They want less moving parts and less expense ( my guess will be they will go for an atkinson cycle rotary engine with direct injection – if it can be used in cruze or sparc also )
The problem is introduction on new engine needs a lot of testing and certification. They can even license if somebody has a certified engine with fits the exact purpose. On the downside , too much investment on this is not worthy if battery technology flies as expected on cost,recharge, life span ,size etc )
Cruze engine may be selected just because the production factors in mind and production with low cost.
The problem is again same – others will come with a high efficiency engine in no time once volt gets popular and GM will loose the edge if battery technology didnt fly as fast as we expect – in terms of power, fast re charging and cost.
On the post : it looks EREV wont be as smooth as EV mode but it should be smoother than other ICE cars
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May 4th, 2009 at 4:45 pm
@ All,
Really nice thread, with some really good points. Now my two cents…
With the radio on you will never notice the genset coming on….
If you turn the radio off and listen very closely, you will hear a paradigm shift…
/Oh ya!
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May 4th, 2009 at 4:48 pm
#72 RB
“Lyle would do it. Statik would blurt it out.
”
——————–
You know him pretty good. Don’t you? Just joking at Statik’s expense. We all need to do that once in a while. But, I still think it is a good idea. Maybe GM could hold Statik’s first born as hostage against him blurting it out. Statik?
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May 4th, 2009 at 5:00 pm
#72 RB
“Lyle would do it. Statik would blurt it out.
”
——————–
#161 N Riley says:
You know him pretty good. Don’t you? Just joking at Statik’s expense. We all need to do that once in a while. But, I still think it is a good idea. Maybe GM could hold Statik’s first born as hostage against him blurting it out. Statik?
====================
….I’ve never been that fond of my first born.
Sidenote:
I’ve actually had to sign more than a few NDAs over the years…clothing business is a surprising phobic one.
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May 4th, 2009 at 5:08 pm
162 Statik,
“I’ve actually had to sign more than a few NDAs over the years…clothing business is a surprising phobic one.”
_________________________
I’m not surprised clothing manufacturers don’t want their employees blabbing about company faults on the internet. They know how damaging “loose threads” can be.
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May 4th, 2009 at 5:42 pm
I’d like a redo on that joke @ 163.
I’m not surprised clothing manufacturers don’t want their employees posting company secrets on internet forums. They know how much trouble “loose threads” can be.
…… . . . … . . loose . . . threads
No?
Tap tap.
Is this thing on?
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May 4th, 2009 at 5:48 pm
Off topic for a moment, but,
Lyle,
Could you ask GM if they are going to get rid of the lead-acid 12 volt battery in favor of another accessory-power approach, in order to eliminate those high risks to software programs in retaining learned functions such as I’ve described above? GM is certainly aware of these very high risks solely and directly caused by lead-acid 12 volt batteries (that are a 7 day, 15 day, or 30 day pay-period mini-bankruptcies for many folks as previously discussed yesterday).
Thanks!
Dan Petit Austin TX
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May 4th, 2009 at 5:49 pm
While reading today’s thread, wonderful ad copy comes to mind…
The fuel powered generator included with every VOLT provides you with an unlimited electric range. No matter how far you travel, the wheels will always be powered by electricity. While your commute can be fuel free, the built-in power plant is what makes the VOLT care free!
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May 4th, 2009 at 6:03 pm
#149
Peter M Says:
May 4th, 2009 at 3:43 pm
I think I’ve read enough of the post here to make the following observation. I just drove a prius this weekend so I have that added experience to add.
It seems to me that the largest problem will be that the battery will only accept a charge at a rate of 2KWH. At maximum power, the genset might produce 50KW. It seems the problem is as follows:
1. You are trailing a semi and need to pass. Battery is a Customer Depletion Point.
2. You step on the accelerator, genset increases to maximum output, all that power is going to the wheels.
3. You pass the semi, and quickly reduce speed by lifting off the gas.
4. Now What? You have the Genset at maximum capacity, but all the excess energy has knowhere to go. Battery can only accept a charge a certain rate. Wheels don’t need the power, so does the genset go back down to a much lower level of output.
This can be summed up as follows. The car does not know what the drive will do next
_____________________________
Wow total speculation with little info from GM, how fun, mind if I jump in. IMO The ICE would be under full duty load and if power is needed to maintain SOC at or slightly above CDP then current from the genset would continue to the battery. If not, closing the throttle to near idle (whatever that is!) would nearly instantaneously reduce engine speed and power output as the genset represents full duty loads (w/no transmission) with a now reduced fuel/air mixture (Yes/No) quickly lowering engine speed, and electric potential although rapidly reduced sends a residual current to the wheels until regen or more acceleration are called.
Power not used by the wheels and battery is wasted heat, but should be very rare and very little unless you need no power at the wheels, such as passing the truck and simultaneously using regen and friction brakes (sounds like a head on collision coming up).
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May 4th, 2009 at 6:09 pm
Clothing…. Canada… Roots?
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May 4th, 2009 at 6:10 pm
If you want to avoid the generator transition issue equip the volt drive train with capacitors; the gen set wouldn’t have to work so hard. Actually I’m quite surprised that this hasn’t been discussed more often on this website. Check out http://www.afstrinity.com/. This combination promises and seems to deliver.
. Seriously, who really is all that concerned about the ICE transition? So long as it delivers and charges the batteries without a significant degradation in over the road performance who gives a hoot.
I really don’t understand the anxiety that seems to be generated on this website. Most of the issues we discuss are interesting, relevant and thought provoking however, in the final analysis it’s all just a WAG (wild a$$ guess) until we see the final product. I’m sure there isn’t an issue that has been raised on our website that GM hasn’t thought off too. For sure, they monitor this website (they’ve admitted to this) and if there was something their engineering team hadn’t thought of (LOL) they would certainly find it here
It’s the 1st generation. This is an engineering given, there will be bugs, there will be faults, there will be issues. We’ll live with them and together work them out. The 2nd and follow on generations will address and resolve issues. It’ll be a better car down the road, that too is just the way it is.
The 2nd geration may very well incorporate an turbine generator. Transition would be seemless and nearly instantaneous so……. let’s get over it.
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May 4th, 2009 at 6:12 pm
Lyle.. looks like you got your work cut out for you on your next interview. Lots of technical details. As long as it doesnt compromise any intelectual property of course.
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May 4th, 2009 at 6:14 pm
Peter M #149
This is a good scenario to discuss. While we can only mostly speculate on what will happen at this point, fortunately GM has given enough information to speculate with or it would be 100% wags. Since the battery is large enough there is no need for the ICE to increase output to match a transient load such as passing a semi or 2 semis. Perhaps they will choose to for other practical reasons but it won’t be required. They have given a chart that shows the battery SOC from customer full all the way through range extended operation and wall charging back to customer full. That chart indicates the ICE will come on at one point to enter range extending mode. Afterward the battery SOC will swing up and down, sometimes swinging below the initiating point for Range Extending Mode. GM has the luxury of “feathering” up the ICE. I presume they will use software to analyze the current power demand as recent demand. They may also incorporate your speed (current and recent)and rate of ascent into the analysis. This could be used to guess your near term power neads and “feather” the ICE up accordingly. Although I don’t think passing will bring about full ICE output in general, there is still the issue of rapid power demand decrease. Breaking after 80mph up a slight incline, reaching the summit after a steep climb, breaking for a light, etc. In the case of rapid power demand decrease, I think they will have to have the engine react quickly and this can be done instantaneously with the throttle as CaptJackSparrow suggests. I’m guessing they will “feathure” up for increase demand and instantaneous or near instaneous throttle down for significant decrease in power demand. This is assuming 16KW charge rate is a design limiting factor.
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May 4th, 2009 at 6:15 pm
#147 john1701a
———————–
You may not agree with the numbers, but he is fairly consistent is actually posting his assumptions. In fact, he doesn’t have “ideal” numbers for the volt. The ideal numbers would assume a 40 mile typically commute rather than 30 miles.
The truth is the Volt, if recharged by a reasonable owner only once a day, can save upto 40 (EPA City and Highway AER)*356= 14,240 miles of gasoline per year.
That would be
284.4 gallons over a 50 MPG EPA Prius
474.6 gallons over a 30 MPG EPA Corolla
569.6 gallons over a 25 MPG EPA Camry
Very few will acchieve these levels of savings however, since very few drive 40 miles each and every day. The change in driving habitis and conditions affects ALL the cars. Using EPA may not predict actual fuel savings, but since the Prius definately won’t get 50 mpg in 32 degree weather with the heater going and the radio and headlights turned on… why do we expect the Volt to be a failure if it doesn’t acchieve 40 AER in the same situation?
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May 4th, 2009 at 6:17 pm
Since we are all guessing, here is how I think GM will/could solve the problem.
GM should rely on dipping into the battery somewhat to avoid revving the engine too high. Most demands for power are not too long in duration. A battery of this size, even at 30% charge, can do the 1/4 mile race a few times without sweating it.
It would not be too hard to figure out what the average power demand is. They could use a several minute trailing average to compute it. The engine and generator could run at or slightly above this average value and it should generally keep up. If the battery gets too low, then they would need to “feather” the throttle up a little. Again, running at this rpm until you are back at 30% charge and then “feathering” (not my word) back down to the running average. If you run at the 5 minute average requirement on the engine, the battery could be used to smooth out the humps in demand.
They should be able to figure out a way to make this smooth and seemless.
My current AC unit is a variable speed unit. It comes on at 30% power and runs for 5 or more mintues to see if it can meet demand. If not, it ramps up more and tries again. I never notice the thing. If it just kicked on, like my last unit, I would notice. I think GM is thinking along these lines.
If you are climbing pikes peak with 3 people like me traveling with you, then the engine will have to max out and stay there for a while.
Big deal. Thats the way most cars I have owned would handle a long steep hill. If I slow down and the engine keeps up its speed, that would be OK too. Its an engine and generator. They are made to do that.
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May 4th, 2009 at 6:22 pm
It would be a nice feature if you had a small button on the stearing wheel that could turn on the ICE in high power demands. Think of these situations.
- About to pass
- climbing a long hill
it could activate in the same principle as a torque converter works today. It would turn on the ICE/Genset and give extra power to the electric motor. It would be the driver’s choice to drive in this mode.
It should stop all the “what about climbing the hill” comments as well.
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May 4th, 2009 at 6:27 pm
Let’s put a twist in this passing the Semi scenario……
OK so you’re on I5 in Southern CA passing the Semi going over the Grapvine. You have it pushing hard, ICE RPM high, batt packs has to kick in you’re using all 150 quoted HP. As you reach the peak you have finished passing and start flying downhill then you see the Highway Patrol. Suddenly your foot is off the accelerator and you are still in “L”, brake regen starts, your ICE is high revving you’re now in the opposite scenario in that you are now generating way more than needed and way more than the batt pack can absorb…..
Does anything burn up?
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May 4th, 2009 at 6:28 pm
The Atkinson cycle engines could be great for the Volt. They are higher efficiency than regular ICE engines at the expense of low end torque. We could run it without needing low end torque. The engine can be run up at rpms of 2000, 2500, etc. in some sweet spots where it is most efficient. It does not need to do anything in the 1000 -1500 rpm range.
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May 4th, 2009 at 6:36 pm
Stick a turbocharger on the engine.
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May 4th, 2009 at 6:39 pm
Carcus1 #134
Of all of the endless speculation that has been spewed on this site. The engine being an Atkinson cycle is probably the safest one. For a reciprocating gas engine, it is ideally suited for an EREV. Average power required, almost never peak power. The only time the battery will be required to supply peak power will be when the battery has reached it’s absolute customer discharge point (I forget the term that Mr. Farah used) and the the power demand is 50KW+. Even then the peak power will be system limited to the generators ~50KW. GM uses Atkinson in their 2-modes, so they know how to implement them. Why do you think they wouldn’t use Atkinson?
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May 4th, 2009 at 6:42 pm
#
Electric Vehicle Owner Says:
May 4th, 2009 at 3:22 pm
@ BillR 137
from Scientific American:
“Drive power for the Volt will come from a 136-kilowatt- (or 160-horsepower-) at-peak permanent-magnet electric motor that produces 320 newton-meters of torque, Zielinsky explains.”
So sad. That’s adequate for a 1,100 pound vehicle in my book. Give the Volt some real power, please, please. The driver can always put it in eco mode. Don’t skimp on the Volt’s heart and soul. Or at least have a gen II power version available at a premium for us power hungry meatheads who know what electric drive is capable of.
Napkin work: 320 Nm = 236.01984000000002 lb-ft of torque. meh. Not impressed.
American muscle cars are NOT dead. They’re just going to be electric from now on. Just to be clear, my preference would be for the Volt to have 750 lb-ft of electric drive torque, when the similar weight Dodge Viper has 510 to 760 lb-ft. Someone talk me down?
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How much torque is generated by a 600+ HP/6100 rpm Viper at 1000 rpm? How much torque is generated by the Volt’s proposed 160 hp motor at .5 rpm?
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May 4th, 2009 at 6:44 pm
“Several Sweet Spots”
Isn’t that an Oxymoron to “Sweet Spot”. I mean if there’s more than one it’s not “Theee” spot therfore not making it sweet anymore.
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May 4th, 2009 at 6:48 pm
@Adrian 177
“Stick a turbocharger on the engine.”
That was a good thought but by design, the bottleneck is the Generator itself. You will probably never get more than 53KW out no matter how you tune the ICE. Tune the ICE and upgrade the Generator maybe. Or at the least upgrade the Generator to a75KW and leave the ICE………aw man nevermind…….
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May 4th, 2009 at 7:00 pm
Steel #172
Because john1701a really dislikes the Volt.
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May 4th, 2009 at 7:07 pm
Binto #174
I believe those comments won’t stop until people actually drive the Volt. There was a long thread about reaching a point of power limitation. The chief engineer admitted that it could be done but not with normal driving. Highway climbs are full of ups and downs and this will be a non-issue for the general public. If somebody wants to drive 85mph every second of their trip to Vail then they may have to get a different car. I would love your button to turn off the ICE when I’m near home. I don’t much nead their hill climbing battery buffer here in southern Florida.
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May 4th, 2009 at 7:08 pm
CaptJackSparrow #180
Hmm…well…never mind
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May 4th, 2009 at 7:25 pm
I smell problems in the GM engineering dept.
This is exactly the news that I feared. Unless GM fesses up on how deeply they will dig into the battery during depletion, the assumption will be that they will do it only sparingly.
This will make the driving experience of the Volt, in certain scenarios “unusual” and worse yet, unacceptable. But, I am sure many of our Volt-anese would be willing to put up with the limitations, but unfortunately the majority of drivers on the road will not.
GM lets clear this up immediately! Either we are making poor assumptions, or the Volt is going to need an “upgrade”. Like a larger engine/motor/genset (can you say schedule slip?)
I have my own engineering problems at work, and thinking about GM’s makes me slightly ill.
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May 4th, 2009 at 7:26 pm
#164 carcus1 says:
I’m not surprised clothing manufacturers don’t want their employees posting company secrets on internet forums. They know how much trouble “loose threads” can be.
…… . . . … . . loose . . . threads
No?
Tap tap.
Is this thing on?
=========================
/crickets
(Generally, I make/design the clothes for a company/university/sport team, and they have some kind of ‘new hotness’ logo/brand on it they think will change the world…and that for some reason I may be inclined to share it with the world…hence the NDAs)
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May 4th, 2009 at 7:27 pm
#175 CaptJackSparrow
Does anything burn up?
____________________
The brake pads?
Pure conjecture:Unfortunately, during the lag in reaction time between taking your foot off the accelerator and stomping on the brakes the motor was still engaged putting a lot of power to the wheels, therefore I’m afraid smokey’s already hitting the lights.
Then the throttle closes, and the engine drops to idle, the motor, now in reverse for regen goes to an electronically controlled equivalent of N, and any momentarily unneeded current that was received is shunted away by motor cooling(air/liquid?). See you in court!
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May 4th, 2009 at 7:33 pm
#185
JEC Says:
May 4th, 2009 at 7:25 pm
I smell problems in the GM engineering dept.
This is exactly the news that I feared. Unless GM fesses up on how deeply they will dig into the battery during depletion, the assumption will be that they will do it only sparingly.
This will make the driving experience of the Volt, in certain scenarios “unusual” and worse yet, unacceptable. But, I am sure many of our Volt-anese would be willing to put up with the limitations, but unfortunately the majority of drivers on the road will not
______________________
This is called learning to drive a new vehicle type. Bicycles, differ from motorcycles, automatics from manuals, turbocharged V 12’s differ from four bangers. Maybe I’m a little tired but I’m tempted to say big whoop!
I would even agree with those who say if it feels exactly like a conventional ICE then GM has failed in some respects.
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May 4th, 2009 at 7:59 pm
#149 Peter M
“It seems to me that the largest problem will be that the battery will only accept a charge at a rate of 2KWH.”
If the battery can deliver 110 kW, why is it limited to 2 kW in charging? This will severely limit the regen braking (going down a long steep grade will generate more than 2 kW).
Perhaps you are thinking of the plug-in portion of the Volt where the power from the grid must go through a transformer/charger to charge the battery.
I would imagine the battery pack can accept far more than 2 kW. Any battery experts who can help with this?
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May 4th, 2009 at 8:09 pm
#92 GuyMan says
I agree that this seems like something that should have been forseen about 2 years ago, but clearly, they are dealing with it now… I’m just sort of surprised they didn’t “limit” the mule test to avoid hills, or just control the circumstances under which the ICE would cut on.. It’s makes one think that they have a way to go yet…
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A good summary. I agree.
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May 4th, 2009 at 8:10 pm
I can see a great deal of merit to what Dan Petit #158 says.
As mentioned, it will not be prudent to deplete the battery pack to 10%. So let’s assume that the absolute minimum is 20%. If you live in an area with lots of steep hills or mountains, or you are an extremely aggressive driver, it may be possible to drain the battery pack to this 20% SOC and experience power loss. The GM software will recognize this and note it in its log.
If this type of problem is repeated somewhat frequently, the software can up the CDP to 40% (or what ever number is appropriate). Then you will have a 20% buffer instead of a 10% buffer, and will be able to go longer distances without power loss. The drawback, however, its that you will get less energy from the grid, and use more gasoline or E85.
I’m sure these are just some of the issues that GM is dealing with.
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May 4th, 2009 at 8:17 pm
At #48 statik gave us the following quote from Andrew Farah
“…if you’re trying to go up a hill with only basically half the power capability? That’s where the battery comes back into play. Because the customer depletion point is not full depletion, there’s still energy available. That’s by design. The idea is during certain other peak situations such as climbing a hill or merging into traffic, you will actually take some more energy out of the battery. So you may actually come down a little bit below customer depletion level.”
“And then when you take your foot off the gas, as an example when you’re done doing the merge, we had taken a little bit out and the battery has a little less in it. So what we’ll do then is we will opportunistically put that energy back into the battery either through regenerative braking or if we have to we will take some of the energy that’s not needed to turn the wheels and bring the battery up to the customer depletion level.”
—————————————————–
So what the chief engineer said was that the ICE runs at the average power, not the peak power. We have all been thinking of the positive side of his statement, that the ICE does not have to deliver peak power but could deliver less, the average.
The other side of the statement has its consequences too –>When the Volt is requiring less than average power, the ICE still is running fast enough to produce the average power. That is, when one slows down, the ICE does not, and if one has been requiring a substantial amount of power on average over the last few minutes, then when one slows down the ICE is running fast, so that, on average, the ICE can get the battery SOC back to 30%. That is, when you stopped at the light, the engine kept roaring.
So maybe what has happened is that the early description by Farah of how it was going to be is exactly how it was built. Then they drove it, and when they did they didn’t like it. Too much NVH at low speed. Now they are trying to figure out a re-design that has a better feel.
It’s all a speculation, of course, but I think plausible.
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May 4th, 2009 at 8:24 pm
#178 Koz,
” Why do you think they wouldn’t use Atkinson?”
__________________
Power. The 3500# volt is going to need every bit of 53 KW (71hp) out of that generator in order for the volt to perform in high power demand situations after the CDP (i.e passing a semi on the trip to vail). 53 kw = 71 Hp. We don’t know how efficient this generator is, but the internets say anything from 95% to 75% loss is possible. That would put a 90 hp otto cycle genset down to 85.5 hp to as little as 67.5 hp.
In order to convert the 1.4 litre engine from otto to atkinson cycle you would gain efficiency but lose as much as 30% power. So with generator efficiency losses and now a 30% loss from the atkinson conversion, you’re generator (though rated at 53kw or 71hp) will now only be producing about 59.85 hp to 47.25 hp.
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May 4th, 2009 at 8:25 pm
As long as the quality of the car is good and the actions make sense the driver will get use to it quickly.
Many people worry about giving a name to something but does it really matter? Take the Wii for example. Even Nintendo fans were saying the name would ruin the game. Has it? Not even a silly name hurt it. The amount of jokes in the beginning were huge. Same for Obama. Nobody is laughing now.
Also, GM can put in several different modes. They can tell the driver that this is the most ECO setting (constant RPM) or give them a standard feel (RPM matches somewhat to the pedal position) or many different combinations.
That’s why this is taking so long. The tweaking of the software can take the longest because it’s the most flexible component on the car. Too many cooks want this change or that change and that has a habit of delaying things.
I’m not worried at all. They have almost infinite flexibility as to how the ICE acts. Additionally, they will be able to change that even after the car is sold by utilizing software updates.
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May 4th, 2009 at 8:36 pm
Regarding quick recharge rate for up-charging before mountainous demand and lowered Genset loading/noise.
While not likely available in Gen 1 battery array chemistry, in that last advancement by MIT, they seemed to have perfected a way to align the electrons into and out of the electrode nanotubes so efficiently as to mimic an ultracap, while at the same time greatly reducing degradation (about a month ago it was announced and posted here). That development, which they say involved an easy alteration of the production lines, would be the advancing factor regarding quick acceptance of power from the genset for Genset Quietlearn in my post at #158 above.
This would be the practical reason to lease the gen 1 battery array chemistry so as to preserve an option to go to the A123 gen 2 chemistry (if it were to be utilized then). The very measurable residual life of the original battery could be used/bought back as an OEM warranty replacement pack (credited to you toward a gen 2 chemistry of A123) for someone elses Volt (living on the flat prairies) at the end of the term of your lease, especially if the lease would function to get the original purchase price monthly payment down by at least 40 bucks.
All this stuff ties together very nicely if you like to think about it a lot.
Dan Petit Austin TX
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May 4th, 2009 at 8:45 pm
Another thought in passing.
How about the time you’re out for a nice night time mission in your volt. You’ve been running in CDP mode for a while but the road is flat and you’ve been passing some slower cars on the two lane highway with no problem. You now come up on 2 slow interplanetary transports. You mash the electron pedal and the volt smooths out into the passing lane just like it has before (the genset along with a little bit of battery reserve provide adequate acceleration). But just as you get to the cab of the lead semi, your battery hits the “dead bottom (20%soc or whatever) of the pack and the BMS says “I’ve giv’n her all she’s got captain, an’ I canna give her no more.”. Your acceleration fades, the lead truck has now stopped moving back, and the oncoming klingon headlights grow larger.
Is there a button to be mashed underneath the “gas pedal” that tells the BMS “Scotty I need more power. I DON’T CARE IF YOU MELT THE DiLITHIUM ION CRYSTALS! MORE POWER!
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May 4th, 2009 at 8:52 pm
#196 add,
BMS = Battery Management Scotty
Your license plate is VLT-1701
Your copilot’s ears are pointed .
The cover of your mileage log reads “Captains Log”
. . . . you get the picture
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May 4th, 2009 at 8:57 pm
196 carcus1
I like the analogy!
Maybe Dr McCoy could chime in after you headfirst into one of the transports and your body is strewn across the median as he tries to put you back together…..”Damn it Jim, I’m only a Doctor!”
Perhaps all can be saved, if we can get Spock to “just reverse the polarity”
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May 4th, 2009 at 9:25 pm
Thanks for the laugh guys, the best in a while..
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May 4th, 2009 at 9:48 pm
Off topic,
Whoa, check this out!
At 0:55 into the Ford promo video. Whatserface says the plug in escape is getting 120 mpg for the first 30 miles and 80 mpg after that!?
I think she misspoke and meant 120 mpg city or 80 mpg highway for the first 30 miles (i.e. up to plug in battery depletion) But that’s not how she said it.
http://www.thefordstory.com/?searchid=426441%7C28125566%7C205373347
Thanks for the link, Lyle.
/regardless on the misspeak, that’s the first time I’ve seen Ford with such an official announcement on those 120/80 first 30miles numbers. I think that’s pretty darn good considering the size of the escape and only a 10kwh battery.
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May 4th, 2009 at 9:50 pm
#196 carcus1:
…you are feeling sleepy
————————–
Side note:
The Chrysler bankruptcy proceedings are really, really ugly. I’ve been following it loosely and reading the filings throughout today. (No, I won’t bore you with the details…you can read them at scribd if you don’t have a law access program)
The gov’t is running some questionable (to say the least) plays, skirting the law, trying some bush-league procedural trickes, and some other serious chicanery, but the bondholder’s guy (Gerard Uzzi) is right there killing them on it every time.
It is like he is watching them put out motions and he is drafting his retorts and objections (with significant merit) and getting them back to the judge almost concurrently. He is making a ton of sense, plenty of rule of law behind his statements and the government is just…I don’t know, it is almost embarassing for them. He is making them look foolish.
If the gov’t is learning anything about how a GSB is going to go for GM…they should learn to get this guy on their payroll before they try to do it. Just pay off Chrysler’s bondholders, get on with the show…and put him on retainer.
/Chrysler bondholder’s are either getting paid….or Chrysler is going to be in bankruptcy a lot longer than 30 days. This judge will never work again (at least not with credibility) if he doesn’t side with Uzzi. It is like Perry Mason vs. the random snarly, large forehanded guy of the week.
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May 4th, 2009 at 9:53 pm
The generator puts out its optimum electricity at a specific RPM. The ICE will be tuned to operate at that specific RPM. Anyone who says you that you get better rmpg operating at all kinds of rpms some very far from optimum, rather than mpg achieved at a specific rpm and tuned for that rpm is DAFT.
An ICE running Atkinson cycle and eventually HCCI at that tuned and targeted rpm maybe achieving close to 100 mpg. Tuned operation is much better than a mechanical contribution at varying rpms as in a HEV. Any Engineer would tell you that, and this one is.
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May 4th, 2009 at 10:03 pm
#201 Statik,
You remind me of Spock. No sense of humor.
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May 4th, 2009 at 11:14 pm
Anyone hear about the Detroit Elecric?
http://news.cnet.com/8301-11128_3-10206089-54.html?tag=mncol;title
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May 4th, 2009 at 11:49 pm
Is it the same Detroit Electric?
How have they been keeping themselves busy in the mean time?
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May 4th, 2009 at 11:53 pm
#202 Anthony BC “Anyone hear about the Detroit Elecric?”
Thanks for the link. From the Article, “In 1900, 28 percent of all cars produced were electric, but 20 years later the industry was all but dead, according to Michael Brian Schiffer, author of a history of electric cars in the U.S. The original Detroit Electric went out of business in the 1930s”
____________________________
I’ve read that electric cars were competitive until Cadillac popularized the electric starter for ICE’s. So that makes twice GM has “killed the electric car”, not counting electric streetcars of course.
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May 5th, 2009 at 12:22 am
Carcus1 #193
The generator is rated at 53KW, not necessarily the 1.4 liter ICE. So a 100hp rated 4-cyl I4 will be fine in your example?
http://jalopnik.com/5054712/gm-officially-announces-14+liter-four+cylinder-for-chevy-cruze-volt-to-be-built-in-flint-mi
Atkinson will provide 53kw just fine. It is in line with the Prius 1.5l I4.
http://en.wikipedia.org/wiki/Toyota_Prius
Not that it matters for your example. I don’t expect GM will just completely shut off the battery immediately or unwarned for that very rare occasion.
Any other reason you think it won’t be Atkinson?
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May 5th, 2009 at 12:46 am
ICE RPM is an easy problem to overcome. Use a variometer to check position plus/minus sea level. This will retest the Volt position, in one minute intervals, over or under sea level. So the ICE will know if the the Volt is climbing or coasting. To complete the calibration, tie in the actual MPH number.
100 FMP rise + 50 MPH = ICE 2800 RPM
10 FPM rise + 70 MPH = ICE 2400 RPM
50 FPM drop + 60 MPH = ICE 2200
300 FPM rise + 50 MPH = ICE 3000
0 FPM rise + 5 MPH = ICE 1800
=D~
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May 5th, 2009 at 2:12 am
______________________________________________________
Does Plug-In market maker GM need to look over its shoulder?
“…I can’t tell you how excited I am about the day a Ford customer can go inside and buy a plug-in hybrid”
Source:
http://www.youtube.com/watch?v=COZ3awzDf-o&feature=player_embedded
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May 5th, 2009 at 6:07 am
I am a big GM supporter but it looks like Ford is kicking GMs but.
The hybrid Escape looks good and the plug in version is already in testing (given to Southern California Edison). GM has essentially shelved their plans for the plug-in hybrid Vue and Ford is marching on.
These plug-in hybrid SUVs should be big sellers when they are finally ready for mass production. It looks like Ford will be beating GM to the punch.
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May 5th, 2009 at 7:02 am
#207 Koz,
My post @ 193 still stands.
The engine we’re discussing here is GM/Opel’s “family 0″ 1.4L Otto cycle engine. There is no official source that lists it at anything other than 90hp/66kw that I can find. (looks like jalopnik got confused, their listed source does not claim 100 hp for the normally aspirated 1.4). Here’s what Opel says:
http://www.gm-press.com/HU/site/article.php?aid=619
If you were to do nothing other than convert to an atkinson cycle. You can expect to lose 30% on the power. That’s what I”ve read, but on this there really can be no official source. I’ll admit it’s speculation.
Now if GM wants to borrow Toyota’s vvt-i technology in the process of converting the 1.4 to atkinson (and add another .1 litre), we’re talking about something altogether different.
P.S. is there any reference anywhere that says GM is working on converting the 1.4 to Atkinson??
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May 5th, 2009 at 10:01 am
@ jeffhre 179
Excellent point. Max torque at 1 rpm up to max power means that electric drive can always give you a nice kick in the a$$ off the line (if and only if you want that) even if the 0-60 times are average and near linear acceleration and deceleration for superior application of torque in bad road conditions.
I’ve thought about this a long time now. I’m ok (but not thrilled) with 236 lb-ft of torque and real world 0-60 of 9.5 seconds (better than the new Prius and ok relative to your average new vehicle) or less. I get it that GM is trying to pull electric drive from the fringe (high performance or very different app (freight train, fork lift, mining dump truck, lawn mover, power tool, washing machine) or weird) into mainstream personal transportation and that means fairly mainstream full gasser emulation for the first generation.
The more I use electric drive and directly compare to full gassers around me, the more amazed and impressed I’ve been at how much performance engineers have gotten out of the highly inefficient combustion engines over the decades, with large size, heavy fuel use, brilliant gearing and shifting mechanisms and the hundreds of extra parts and technology add-ons to combustion engines that electric drive doesn’t require at all.
I simply hope at some time that GM will offer a higher performance electric drive vehicle (use an HH designation – for Hyper-Hoon?) and of course charge a premium, for that muscle head niche. I understand that high performance cars are often small volume losers for large automakers, more about halo and marketing than profits, so I’m willing to let that idea go if it means making the Volt a mainstream winner and GM viable. Let the niche players do the niche markets, I suppose, if need be.
@ jeffhre 188
“I would even agree with those who say if it feels exactly like a conventional ICE then GM has failed in some respects.”
If they figure out how to completely neuter all the positive capabilities and superiority of electric drive, I will cry. And not out of happiness.
@ CaptJackSparrow 180
Three sweet spots = three local optimals, no oxymoron there. If they ain’t doing it in matrix form already, they’ve already missed some multiple opportunities for success (the Volt excels not just at point g but also at x, y, z and q, etc. in situations b,c,d,e, etc.).
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