Abstract: An AC electric motor, an inverter and a controller are mounted on an electric powered vehicle. The controller includes a voltage deviation calculating unit, a modulation factor calculating unit, and a mode switching determination unit. The voltage deviation calculating unit calculates a voltage deviation between a first voltage command when the rectangular wave voltage control is executed and a second voltage command when pulse width modulation control is executed, by inputting a current deviation to a voltage equation of the AC electric motor. Modulation factor calculating unit calculates the modulation factor based on the first voltage command and the voltage deviation. The mode switching determination unit determines whether or not control mode of the AC electric motor from the rectangular wave voltage control to the pulse width modulation control is necessary, based on the modulation factor.

Abstract: In a control of an AC motor that uses a PWM control and a rectangular-wave control, when switching is conducted from the rectangular-wave control to the PWM control, a current command generated in a current command generation unit is corrected so as to smooth the variations in a time axis direction on the basis of a target torque command value by taking the final current state in the rectangular-wave control immediately prior to switching as an initial value, thereby generating a current command after the correction. An inverter is current feedback-controlled based on the current command after the correction. As a result, the continuity from the current state immediately prior to switching of the rectangular-wave control can be ensured for the current command in the PWM control.

Abstract: An AC electric motor, an inverter and a controller are mounted on an electric powered vehicle. The controller includes a voltage deviation calculating unit, a modulation factor calculating unit, and a mode switching determination unit. The voltage deviation calculating unit calculates a voltage deviation between a first voltage command when the rectangular wave voltage control is executed and a second voltage command when pulse width modulation control is executed, by inputting a current deviation to a voltage equation of the AC electric motor. Modulation factor calculating unit calculates the modulation factor based on the first voltage command and the voltage deviation. The mode switching determination unit determines whether or not control mode of the AC electric motor from the rectangular wave voltage control to the pulse width modulation control is necessary, based on the modulation factor.

Abstract: In a control of an AC motor that uses a PWM control and a rectangular-wave control, when switching is conducted from the rectangular-wave control to the PWM control, a current command generated in a current command generation unit is corrected so as to smooth the variations in a time axis direction on the basis of a target torque command value by taking the final current state in the rectangular-wave control immediately prior to switching as an initial value, thereby generating a current command after the correction. An inverter is current feedback-controlled based on the current command after the correction. As a result, the continuity from the current state immediately prior to switching of the rectangular-wave control can be ensured for the current command in the PWM control.