Global dynamic sliding mode control of PMSM speed servo systems base on extended state observer

Base on the the high performance requirements of permanent magnet synchronous motor(PMSM) speed servo system for non-sinusoidal oscillation control system of continuous casting mold, a global dynamic sliding mode(GDSM) control method is proposed, The reaching law of the sliding mode is designed by exponential fast terminal sliding mode(EFTSM) method and the controllers could effectively diminish chattering by designing the first derivative of control output which contains discontinuous function of sliding mode control; Considers the time variation of parameters perturbation and load disturbance of PMSM, a extended state observer (ESO) is constructed to observe the dynamic observation of total system perturbation and conduct feedforward compensation; theoretical analysis shows that the closed-loop system is global bounded stability; The simulated results show that the static and dynamic performance of the PMSM speed servo control system can be significantly improved by using the proposed method.