To realize a power module for a three-phase inverter having a winding current detector circuit which can detect information of the winding current of a three-phase motor with a low power loss and a high accuracy.

The power module for the three-phase inverter driven by a PWM signal for driving a sine wave comprises IGBTs 114 to 116 with sensors in the lower arm of a three-phase full-bridge circuit having a main emitter connected to a ground terminal 13, a shunt resistor 14 having a low resistance and connected between the emitter of the sensor and the ground terminal, and two diodes D2, D3 having split anodes to supply currents corresponding to predetermined dividing ratio between a collector and the main emitter and between the collector and the sense emitter of the sensor, thereby processing a voltage generated at the shunt resistor by an amplifier 16 and a splitting ratio compensator 17, thereby detecting the current winding of a three-phase motor 20.