Robust Fractional Order Sliding Mode Control Scheme for Permanent Magnet Synchronous Motor: Stability Analysis and Implementation

Abstract

This paper presents a novel robust fractional order sliding mode control scheme for velocity control of permanent magnet synchronous motor (PMSM) under the existence of the parameters variations or/and external load disturbance. A non-linear fractional order sliding mode surface is proposed and a fractional order control law based finite time convergence to the origin is designed. Using the fractional order Lyapunov stability theorem and sliding mode control theory, the sliding mode control law, including equivalent control and reaching control, is derived to ensure the existence of the sliding motion. It is mathematically proved that the states of the error can reach the proposed non-linear sliding mode surface in finite time. The introduced method is successfully applied for the velocity control of PMSM in simulations, and the results show that the proposed control scheme is robust with regard to external load disturbance and parameters variations for PMSM.