Patent ID: 7759885

Claim:
A motor drive device comprising: a drive circuit driving a motor, a motor drive control circuit controlling said drive circuit such that output torque of said motor follows a first torque command, a voltage converter for voltage conversion of power from a power source for input to said drive circuit, and a voltage conversion control circuit controlling said voltage conversion such that an output voltage matches a voltage command, wherein said motor drive control circuit comprises a first damping control unit setting in advance a setting range with predetermined torque independent of a variation component of a revolution count of said motor as an upper limit value to encompass a variation range of output torque expected when said motor is driven, for damping torque to suppress pulsation of output torque of said motor, and generating said damping torque based on said variation component of said motor revolution count in said setting range, and adding said generated damping torque to target drive torque as said first torque command, said voltage conversion control circuit determining said voltage command based on a result of adding the upper limit value of said damping torque corresponding to said predetermined torque to said target drive torque.