Improved Sliding Mode Current Control Based on Extended-State-Observer for PMSM

In order to improve the dynamic response speed of the current controllers of Permanent-Magnet Synchronous Motor (PMSM) drive systems, while considering the chattering problem of sliding mode control and the effect of the internal disturbance of PMSM, an improved exponential approaching law–based sliding mode current control scheme for PMSM drive systems is proposed in this paper. Firstly, the principle and the advantages of the SMC with approaching law method are introduced. Then, a SMCC based on exponential approaching law (E-SMCC) is designed to accelerate the convergence speed of PMSM drive system while alleviating the chattering problem. Finally, a modified Extended-State-Observer (ESO) that enables online estimation of the internal disturbance of PMSM is proposed to obtain the ESO-ESMCC scheme. The simulation results show that the proposed method is effective and accurate, with a faster convergence speed and minor chattering problem.