Quote:
Originally Posted by a_Username
So if there isn't a mechanical linkage to the wheels, then it would be classified as an EV, correct? I gotta say though, the GMI thread on this is helpful. |
Correct. This post explains it fairly well...
1. Leaving home with a fully charged battery pack provides 40 or so miles of driving range with the engine and generator inoperative. The 149-hp permanent-magnet AC motor draws electricity from the 16kWh battery pack to drive the front wheels through a 7.0:1 speed reducer/torque multiplier.
2. Like any energy-conversion device, electric motors are more efficient at certain operating speeds. When the Volt exceeds fifty mph, a clutch holding the planetary gear set's ring gear is released. A second clutch engages to connect that ring gear to the smaller of the two electric motors. Now both electric motors draw electricity from the battery pack and the effective drive ratio shifts to 2.16:1. Top speed is governed at 100mph.
3. When the Volt's battery is depleted to a 30-percent or so state of charge, the gasoline engine is automatically started to give the battery a rest. The clutch connecting the gasoline engine to the smaller electric machine closes so that this device, now acting as a generator, can provide electricity to the main electric-drive motor. Another clutch holds the ring gear fixed, yielding a 7.0:1 overall drive ratio between the motor and the half shafts powering the Volt's front wheels. This regime is used for speeds below 30 mph.
4. At higher cruising speeds, the planetary ring gear is again released, shifting the AC motor drive ratio to 2.16:1. The engine continues providing the power to spin the generator which in turn supplies the drive motor with electric current. In addition, the engine supplies torque to the planetary ring gear through the smaller electric machine.
(This is the engine driving-the-wheels scenario heretofore denied by GM.) Operating in this regime, the Volt is both a series hybrid and a parallel hybrid.
I expect Edmunds and Jalopnik to issue retractions.