Anti-load disturbance control method based on torque sliding mode observer

The load torque disturbance will affect the control of permanent magnet synchronous motor (PMSM). To solve this problem, this paper proposes a load torque sliding mode observer. The state variables are speed and load torque; errors between the real and the observed speed are selected as a sliding mode hyper plane. The observer has a simple structure and can identify load torque of permanent magnet synchronous motor under different current control strategies. Through the introduction of load torque feed-forward compensation, the influence on the performance of control system caused by load torque disturbance can be inhibited. Theoretical analysis and experimental results show that the sliding mode torque observer can estimate the load torque precisely, and the feed-forward compensation can improve the dynamic response efficiently.