A Model Predictive Current Control Based on Sliding Mode Speed Controller for PMSM

To solve the problems such as poor anti-interference performance and more steady-state current harmonic components of a permanent magnet synchronous motor(PMSM) drive system based on traditional PI control, this paper presents a model predictive control method based on sliding-mode-controller (SMC-MPC). Firstly, a sliding mode speed controller based on exponential reaching law is designed to replace the traditional PI speed controller, and to reduce the influence of the load disturbance on system performance. Secondly, the model predictive current control is adopted based on the discrete model of PMSM to reduce current harmonics and improve the torque control accuracy. Then the cost function is designed by controlling the d- and q-axis current, and the optimal output voltage vector is obtained to drive the motor. Finally, compared with the traditional PI method, the simulation results show that the proposed method not only improves the robustness of the system to load disturbance effectively, but also decreases the ripples of current and torque. The presented method has good dynamic and static performance for PMSM drive system.