Killacycle series-parallel shifter

[Joshua Bretz]

The killacycle is pretty cool, but that's not the point of this post.

I noticed in one of their press releases that they switch 2 motors from series to parallel on the fly to get more torque at low speed.

Here's the excerpt:

We also implemented a contactor system that allows the bike to shift the motors from series connection on the launch, to parallel connection further down the track. This allows us to push 2000 amps through BOTH motors on the starting line to get something close to a total of 800 ft-lbs of torque. This results in about 2000 ft-lbs of torque on the back tire.

Here's the full press release:

http://www.killacycle.com/category/press-releases/

Maybe this applies to the Volt? Gen 2?

[ross]

GM will probably be more interested in things that increase the EV range, but once we have a market, there's no telling what we'll see.

Good thing about the Killacycle, they're using A123 batteries which seem to be working well. What they've been burning up is the controllers, bodes well for A123.

[Tom]

The series/parallel arrangement applies to a wound DC motor. This would not apply to an AC PM motor.

[Joshua Bretz]

See this link for a way that series/parallel shifting can be accomplished by driving a many-pole PM motor with different harmonics:

http://www.chorusmotors.com/demo/index.demo.html

Cool stuff

[GearheadGeek]

The killacycle is pretty cool, but that's not the point of this post.

I noticed in one of their press releases that they switch 2 motors from series to parallel on the fly to get more torque at low speed.

Here's the excerpt:

We also implemented a contactor system that allows the bike to shift the motors from series connection on the launch, to parallel connection further down the track. This allows us to push 2000 amps through BOTH motors on the starting line to get something close to a total of 800 ft-lbs of torque. This results in about 2000 ft-lbs of torque on the back tire.

Here's the full press release:

http://www.killacycle.com/category/press-releases/

Maybe this applies to the Volt? Gen 2?

The "series" and "parallel" they're talking about are types of electrical circuits, not the difference between series hybrid and parallel hybrid.

[Joshua Bretz]

The "series" and "parallel" they're talking about are types of electrical circuits, not the difference between series hybrid and parallel hybrid.

Dude, start over.

[Texas]

Dude, start over.

lol! Classic.