Research on PMSM Sliding-mode Vector Combined Speed Controller Based on Improved Exponential Reaching Law

Abstract Sliding mode control has good robustness, but the traditional sliding mode has the problem of chattering. Aiming at the conflict between velocity and chattering in the approach stage of sliding mode control, a new reaching law is put forward. By improving the isokinetic approach term of the traditional exponential reaching law, the system’s requirements in different stages of sliding mode motion are met, and this contradiction has been effectively improved. At the same time, to better improve the control effect of permanent magnet synchronous motor (PMSM) speed regulation system, combined with the traditional PI control with no static error and no overshoot, a combined speed controller combining sliding mode control and PI control is designed to enhance the robustness of the system. By building a model in Matlab/SIMULINK for simulation, the effectiveness of the improved exponential reaching law and the improvement of the system performance brought by the combined speed controller are verified respectively.