Torque Ripple Suppression of Permanent Magnet Synchronous Motor Based on Improved Duty Ratio Regulation Considering Speed Region

The model predictive control (MPC) with duty ratio regulation has been widely studied. However, most of the existing MPC regulates the duty ratio without considering the speed region. In this paper, the generation of torque ripple is analyzed quantitatively. Based on the cause of torque ripple, this paper performs a four quadrants correction on the duty ratio regulation. The equation for the torque variation during one inverter cycle is rewritten. The torque variation is calculated in a new perspective. The proposed method can further reduce torque ripple in the whole speed region. In specific, the effect of the proposed method in the low-speed zone is better than that in the high-speed zone. Finally, simulation results are provided to demonstrate the effectiveness of this method.