Motor drive device and torque ripple removal method

摘要

The present invention provides a motor driving device and a method for removing torque pulsation. A pulsation calculator (25) calculates the pulsation component of a dq axis current which is caused by a bias voltage of a current sensor (17) based on an output value of a rotating transformer (15) and an output value of a dq coordinate converter (19). A pulsation subtractor (41) subtracts the pulsation compoent from the dq axis current based on the calculation result of the pulsation calculator (25). On the other hand, a bias voltage calculator (31) calculates the bias voltage of the current sensor (17) based on the calculation result of the bias voltage calculator (31). A bias voltage compensator (33) subtracts a bias voltage calculation result from an output voltage of the current sensor (17). Therefore, the bias voltage of the current sensor (17) is compensated automatically. The torque pulsation caused by the bias voltage of the current sensor (17) is reduced along with the rotationof a rotating motor (11).