A measuring device and method of cogging torque of permanent magnet synchronous motor

This paper is focused on accurately measuring cogging torque of PMSM. The measurement is effected by designing the measurement device where the rotor of permanent magnet synchronous motor( PMSM) is connected with static torque sensor while the stator is driven by DC motor. The device works by continuously measuring torque using a high precision data acquisition card and filtering out the interference of power frequency in signal acquisition and natural mechanical oscillation of the sensor using a digital filtering method. Experiments show that the device can trace the change process of cogging torque completely and provides enough engineering accuracy up to 0. 2%.