Comments on: Chief Powertrain Engineer Pleased With Chevy Volt’s Charge-Sustaining Mode

By: jeffhre

jeffhre — Sun, 22 Nov 2009 05:59:00 +0000

Herm: I can see it happening on a race track.. and you know that is the first thing many testers (with a hatchet to bury) will do. The second thing they will test is CS Mode mpg at a brisk pace of 75mph. Witness what Top Gear did to the Prius on a race track.This will be a serious marketing challenge to the Volt.

Perhaps, although it hasn't been a marketing challenge for the Prius or at a much smaller scale for the Tesla Roadster. Besides who in NA cares about what the Stig and Clarkson do anyway?

By: jeffhre

jeffhre — Sun, 22 Nov 2009 05:36:03 +0000

Bruce: Please consider that some people, (me for instance), are interested in the performance aspects of electric drive, and would want their engines running almost all the time keeping the battery fully charged for the next big power boost. People like us would want a performance mode for the electric drive software.

Full performance 100% of the time!! Hooowa! Perhaps look into a Camaro SS or Mustang GT. If electric propulsion is really that important the Tesla fits the bill. I don't think the Volt is right for you, and by all means stay away from the disappointment of a Prius or heaven forbid...Insight.

By: Miguel Dorta

Miguel Dorta — Fri, 20 Nov 2009 02:12:35 +0000

I would like to hear a little bit about how the intensive use of, for example, air conditioning plus stereo plus lights would affect Volt’s sustaining mode and depleting mode.
Let’s say you are in a very cold weather and need calefaction intensively.
Would Volt still go for 40 miles while in pure electric mode?

By: Dan Petit

Dan Petit — Sat, 14 Nov 2009 23:14:37 +0000

JohnK: Just noticed this post on the Voltage web site: “I have no idea why Alex Cattelan was so obtuse in this interview. It is very clear that there is no mechanical coupling between the generator and the traction motor. She made things sound much more complicated than they actually are:During AER all the power comes from the battery and the generator is not running.When battery is below 30% the generator powers the traction motor under most conditions (note it does NOT charge the battery).Under some conditions like acceleration or going up hills, if the generator cannot supply all the power required, the battery may assist. Under these conditions the battery will drop below 30% charge.If the battery is below the 30% level and the generator has extra capacity (i.e. not going up hill) then the extra capacity will be used to bring the battery back up to the 30% level.The “coupling” she refers to is when the generator is directly powering the traction motor and not charging the battery. ” The person posting has a handle called “innovator”.Sounds like an engineer working on the Volt.

A very strong "Thank you" Mr. JohnK. I think it's a great idea to come back a few times to each previous thread to see what final commentaries become posted. There often are exceptional clarifications at the very end of the thread here, often missed as the majority of readers move on. Technical thinkers are very often less technically-clear at the end of a very long workday when additionally-tasked to extend expressive clarity for questions posed. The technical mind is not some sort of infinite-thinking-capacity/peak-productive computer that we expect of hardware. (Peak technicians intellectual performance is 4 analytic/clearly-expressing hours per day for the deep technologies such as this one). (The remainder of the workday is routine administrative tasking). As well, only over a long period of time (12 hours to 16 hours per project) can we can then expect to have a conclusive pattern of results of an overall performance from exceptional thinkers assigned to the complex technologies. In short, it takes a really long time to get to know technical people sometimes. But it is always worth it!! Thanks again, JohnK.

By: JohnK

JohnK — Sat, 14 Nov 2009 17:14:38 +0000

Just noticed this post on the Voltage web site: “I have no idea why Alex Cattelan was so obtuse in this interview. It is very clear that there is no mechanical coupling between the generator and the traction motor. She made things sound much more complicated than they actually are:

During AER all the power comes from the battery and the generator is not running.

When battery is below 30% the generator powers the traction motor under most conditions (note it does NOT charge the battery).

Under some conditions like acceleration or going up hills, if the generator cannot supply all the power required, the battery may assist. Under these conditions the battery will drop below 30% charge.

If the battery is below the 30% level and the generator has extra capacity (i.e. not going up hill) then the extra capacity will be used to bring the battery back up to the 30% level.

The “coupling” she refers to is when the generator is directly powering the traction motor and not charging the battery. ”
The person posting has a handle called “innovator”. Sounds like an engineer working on the Volt.