A controller for a wound-rotor induction motor includes a first voltage-type converter connected to a secondary winding of the motor, a capacitor for smoothing DC output thereof, a second voltage-type converter to supply an AC power supply with regenerated secondary power, a speed detector of the motor, a secondary current detector of the motor, a DC voltage detector applied to the capacitor, a speed controller for controlling the speed by the speed detector and outputting a secondary referential current, a first PWM controller to control the secondary current in response to the referential current, and to output a voltage signal by witch switching elements of the first voltage-type converter are controlled by PWM, and a second PWM controller to control a voltage output from the voltage detector in response to a referential voltage, and to control by PWM switching elements of the second voltage-type converter.