[jacquesm]

> An induction generator produces electrical power when its rotor is turned faster than the synchronous speed...

Yes, that's called overdriving the motor.

>> An induction generator usually draws its excitation power from an electrical grid

> Which is not what they want in a car

You can generate very nice sine waves using modern electronics, tri-phase is also not a problem.

> Also they do want good torque at zero speeds, while it can be done with induction motors it's not ideal

Triphase motors have fantastic torque at zero speeds, see also every (diesel-)electric locomotive ever produced.