An Observer-Based Feedforward Compensation for Additional Torque Disturbances of Permanent Magnet Synchronous Machines

The speed of the Permanent Magnet Synchronous Machine (PMSM) fluctuates due to sudden load torque changes. The fluctuating speed has a negative impact on the performance of the system. To address this problem, an observer-based feedforward compensation method for additional load torque disturbance is proposed in this paper. First, the load torque observer is comprehensively designed with its pole configuration method proposed. Second, incomplete and complete feedforward compensation methods for disturbance rejection are analyzed. The proposed complete feedforward compensation method for disturbance rejection further reduces the effect of load torque disturbances on the system. Finally, the effectiveness of the method is verified by the simulation results, which show that the proposed method effectively reduces the impact of sudden load torque changes on the speed of the system.