Patent ID: 8480522

Claim:
A power plant for driving driven parts, including: a heat engine having an output shaft for outputting power, a first transmission connected to said output shaft of said heat engine and the driven parts, for changing speed of power from said heat engine and transmitting the power to the driven parts, and a rotating machine, wherein said rotating machine comprises: a first rotor having a magnetic pole row that is formed by a predetermined plurality of magnetic poles arranged in a circumferential direction, and has each two adjacent magnetic poles so disposed as to have polarities different from each other, said first rotor being rotatable in the circumferential direction; an unmovable stator having an armature row that is formed by a plurality of armatures arranged in the circumferential direction, and is disposed in a manner opposed to said magnetic pole row, for generating a rotating magnetic field rotating in the circumferential direction between said armature row and said magnetic pole row, by a predetermined plurality of armature magnetic poles generated at said plurality of armatures; and a second rotor having a soft magnetic material element row that is formed by a predetermined plurality of soft magnetic material elements arranged in the circumferential direction in a manner spaced from each other, and is disposed such that said soft magnetic material element row is positioned between said magnetic pole row and said armature row, said second rotor being rotatable in the circumferential direction, wherein a ratio between a number of the armature magnetic poles, a number of the magnetic poles, and a number of said soft magnetic material elements is set to 1:m:(1+m)/2 (m≠1.0), one of said first and second rotors being connected to said output shaft of said heat engine, the other of said first and second rotors being connected to the driven parts.