Volt's Chief Powertrain Engineer Speeks

I see what he means.
The generator becomes a motor to dump excess energy when going down long hills with a full charge in the battery pack and also to start the ICE.
The motor becomes a generator when retarding the car down hills or when braking.
The generator can be electrically coupled to the motor to provide drive to the wheels, it also charges the battery which provides all power in EV mode and additional power in gas mode for acceleration.

No new information.

 

I have not been following the news on the Volt.
Is it STILL one or two years from delivery?

 

Some are spot on too, especially the one about GM's Jabberwockian disclosures.

Everything I've seen about the Volt from GM appears to be written in a way that it can be interpreted to mean anything, rendering all of their communications useless.

 

Limited markets NOV 2010.....

 

By that time, hopefully most/all of the bugs will have been worked out of the aftermarket PHEV kits - like the Enginer kit - and the price will have dropped even more. Currently the ~40 mile EV mode kit is just a couple of grand. That makes our regular old Prius with the mod still a lot cheaper, and a lot more functional, then the all electric 40 mile Volt.

 

It's a Prius without the PSD. Engine is hooked to generator primarily to generate power. Motor is hooked to wheels primarily to drive the car. When required, the engine can run to generate power to pass, electrically, to the motor to drive the wheels, or to recharge the battery in charge-sustaining mode (battery depleted).

To slow down, the 'motor' is driven by the wheels which generates power, stored in the battery. If the battery is going to become overcharged by doing so, the 'generator' can be run as a motor to run the engine as an air pump, to waste energy.

All these things the Prius already does. What the Volt doesn't have is a mechanical connection from engine to wheels. To meet their power demands in charge-sustaining mode, however, the 'range extender' engine has grown to about the same power output as the Prius engine, totally negating the point of going to a series hybrid - that the engine can be sized for much smaller demands. The question really is whether the supposedly increased efficiency in the engine is made up for by the losses in converting from mechanical to electric to electric to mechanical power (a path which in the Prius only 28% of the power goes down).

I'll be interested to see the result, but I'd be surprised to see the Volt matching the Prius 50mpg in charge-sustaining mode, on the US drive cycle (and US gallons).

 

I suspect they will use direct injection to improve the efficiency of the ICE.
Otherwise I think your right.

 

Hi Mike D,

Yep, you are right. They sized that engine for desert mountain climbing. Rather than for the midwest secondary road driving (or rural east anglia).

It should have been a 3 cylinder turbo Diesel about 1 liter. And if it climbs the passes in the Rockies at 35 mph full throttle (like most other cars) so be it.