PURPOSE: To improve fuel consumption by inhibiting the thrust supply when the generation of propulsion is not required, and operating the internal combustion engine with one part out of a plurality of cylinders, though the drive of an auxiliary engine mounted on a car is required to the internal combustion engine.

CONSTITUTION: An internal combustion engine 10 drives drive wheel 19 through a clutch 12, a transmission 14, and a reduction gear 16. Moreover, to the internal combustion engine 10, various kinds of auxiliary engine 20 is coupled mechanically. A controller 24 controls the operation of an electric machine controller 26, receiving the input of an acceleration signal, a revolution signal, a brake signal, etc. The controller 24 can be operated, using a motor 22 as a generator. When a vehicle is stopping and an accelerator is not stepped, the controller 24 inhibits the power supply, and also decides how many cylinders to operate out of plural cylinders constituting the internal combustion engine 10. Hereby, the fuel consumption is reduced.