Patent ID: 7729842

Claim:
A vehicle comprising: a first set of wheels; a second set of wheels, wherein each of the second set of wheels is different than each of the first set of wheels; an internal combustion engine that drives the first set of wheels; a generator, wherein the generator is powered by the internal combustion engine; an inverter connected to an output of the generator; an AC motor connected to an output of the inverter, wherein the AC motor drives the second set of wheels; a required motor power calculator that calculates a motor power required by the AC motor to produce a desired torque at the second set of wheels; a generator controller that controls the generator based on the required motor power; a potential power output calculator that calculates a potential power output by the generator based on a current generating status of the generator; and a motor controller that controls the AC motor by controlling the inverter based on the smaller of the required motor power and the potential power output.