A Modified Reaching Law Based Sliding Mode Controller with an Antidisturbance Approach for Speed Control of PMSM System

Abstract

This paper develops a robust non-linear control system that employs the sliding mode control (SMC) technique to enhance the speed regulation performance of the permanent-magnet-synchronous-motor (PMSM) in the existence of parameter mismatch and external load disturbances. Initially, the modified reaching law-based SMC (MRL-SMC) method is proposed. This MRL-SMC incorporates an exponential sliding surface function and system tracking error to enable adaptive changes in the reaching law during two distinct SMC phases. As a result, this method mitigates the inherent chattering generated in the control input and accelerates the reaching speed of the system states towards the sliding manifold. Moreover, due to high switching gain requirement to suppress the effect of lumped disturbances give rise to large chattering. Therefore, an antidisturbance approach is proposed in composite to MRL-SMC. This method consists of a finite-time disturbance observer for estimating the lumped disturbance and initiate a feedforward compensation of the estimated disturbance to the MRL-SMC. Additionally, the simulation results demonstrate that the proposed speed control technique is more effective compared to conventional SMC. © 2023 IEEE.