Reduction of Torque and Flux Ripples for Robot Motion Control System Based on SVM-DTC

Abstract

The motion quality of the robot is determined by the dynamic response and the static response performance of the internal motors. It is a simple and effective way to analyze the motion quality of the robot by decoupling the robot motion control system into multiple single motor control systems. The robot can obtain the excellent dynamic response performance which is driven by the permanent magnet synchronous motor (PMSM) under direct torque control (DTC) strategy, but there exit large torque ripples in the control system. In this paper, a novel direct torque control scheme based on space vector modulation (SVM-DTC) is proposed, which used a new controller to replace the hysteresis comparator that is used in the traditional control system widely. The new controller is just used in the torque error calculate branch in the proposed S- PI SVM-DTC system. Theoretical analysis show that the new controller can reduce the torque ripple and flux linkage greatly and it can also maintain the fast dynamic response of the control system. The superiority is verified through the simulation results.