Direct Torque Control of Permanent Magnet Synchronous Motor Based on Fast Terminal Sliding Mode

Abstract

To solve the problems of large flux linkage and torque ripple, difficulty to accurately control at very low speed in the conventional direct torque control (DTC) of permanent magnet synchronous motor (PMSM), the chattering free fast terminal sliding mode (FTSM) control is introduced into the PMSM DTC. The proposed control scheme not only preserves fast torque response merit, but also associates with the high robustness of terminal sliding mode. It can drive torque ripple to converge to the equilibrium point in finite time, reduce steady state error, has stronger robustness to motor parameter and disturbance,and it attenuates the chatter. This stability of system is proved by Lyapunov theorem in this paper. The simulation results are presented to the feasibility and effectiveness of this method.