Backstepping control of PMSM drive based on terminal sliding mode load observer

For the low precision and response rate of permanent magnetic synchronous motor (PMSM) speed control system in the presence of load disturbance. A backstepping control method based on terminal sliding mode load observer was proposed. Firstly, the non-singular terminal sliding mode load observer which can make the observation error converge in finite time and compensating the controller with estimation value can improve the control precision. Secondly, the speed controller based on non-singular terminal sliding mode and backstepping can improve the state's convergence rate and enhance system robustness. In the end, demonstrate the system's stability via Lyapunov function. Simulation results show that the proposed method can fast estimate the load torque with high precision and can well track the reference speed.