Patent ID: 8319381

Claim:
An automotive electric motor-generator comprising: a motor comprising: a rotor that is rotatably disposed inside a housing; a stator that is disposed so as to surround a radially-outer side of said rotor; and at least one fan that is fixed to an axial end surface of said rotor, said motor functioning as a generator and as an electric motor; and a power semiconductor apparatus that controls a current that is supplied to said motor, wherein: said power semiconductor apparatus comprises: a fan-shaped first radiating plate that is disposed in a fan shape that is centered around a shaft of said rotor in a plane that is perpendicular to said shaft outside a first axial end of said housing, to which a first switching element that is constituted by an N-channel semiconductor element is mounted, and that has a drain potential for said first switching element; a fan-shaped second radiating plate that is disposed in a fan shape that is centered around said shaft in a plane that is perpendicular to said shaft of said rotor between said first radiating plate and a first axial end surface of said housing, to which a second switching element that is constituted by an N-channel semiconductor element is mounted, and that has a drain potential for said second switching element; first ventilating apertures formed in the first radiating plate so as to pass axially therethrough; and second ventilating apertures formed in the second radiating plate so as to pass axially therethrough.