To eliminate a power feeder device and improve reliability, by generating electromagnetic force between first and second rotors using a stator and transmitting torque of an internal combustion engine to a driving shaft.

A first rotor 1350 is provided between a second rotor 1310 and a first stator 1210. A winding 1211 and a core 1212 for forming a rotating field at the revolution adjustment unit 1200 are fixed, and the rotating field is passed through a magnetic circuit 1352 of a dummy rotor and a magnetic-pole form 1311b formed at an inner circumferential face of the second rotor 1310. While the winding 1211 is fixed, electromagnetic force (torque) is caused between the first and second rotors 1350 and 1320 rotated relatively, and thereby a power feeder device can be eliminated.