MOTOR CONTROL UNIT INCLUDING COGGING TORQUE CORRECTION AMOUNT CALCULATION FUNCTION

摘要

PPROBLEM TO BE SOLVED: To provide a motor control unit for calculating an appropriate cogging torque correction amount even when a component (gravity torque, or the like) except a cogging torque is superposed on a torque command in a fixed low-speed feed operation. PSOLUTION: The motor control unit includes a torque command observation unit for observing a torque command when a motor is operated at a constant speed, an approximation calculation unit for approximately calculating a torque command approximation component from the observed torque command in a section of a multiple of a cogging torque cycle of the motor, a second torque command calculation unit for subtracting the torque command approximation component from the torque command to calculate a second torque command, a second torque command frequency analysis unit for performing frequency analysis to the calculated second torque command to extract each frequency component of a multiple of a fundamental frequency of the cogging torque, and a cogging correction amount calculation unit for calculating a cogging correction amount from amplitude and a phase of each extracted frequency component. PCOPYRIGHT: (C)2011,JPO&INPIT