Auto-Compensation System of Torque Ripple in DD motors

Abstract

In the field of motion control, a torque ripple causes a serious problem. Since a direct drive motor with a magnet rotor uses a rare-earth magnet, the torque ripple is more serious than that of the conventional servomotors. The paper presents an auto-compensation of torque ripple using a software-implemented torque observer. The frequency and amplitude of torque ripple can be obtained in the controller by using the estimated torque from an observer, and the autonomous generation of compensating current component for a torque ripple is possible. The proposed algorithm has been verified by experiments.