Patent ID: 7683511

Claim:
A power converter arranged in series and coaxial with a motor along a direction of an output shaft to form a unitary structure through which the output shaft extends, comprising: a plurality of coolers each of which extends along a radial direction with respect to an output shaft so as to be perpendicular to the output shaft and has a cooling surface defined by a direction parallel to the output shaft and the radial direction, each of the plurality of coolers being formed with a plurality of coolant passageways therein such that each of the plurality of coolant passageways linearly extends along a direction parallel to the radial direction or along a direction parallel to the output shaft; and a plurality of power semiconductor modules, each of which is mounted on the cooling surface of corresponding one of the plurality of coolers in a symmetric manner relative to the corresponding one of the plurality of coolers, and extends in the radial direction along with the cooling surface of the cooler, to supply electric power to a motor.