Improved Drive Performance of Linear Induction Machine Based on Direct Thrust Control and Sliding Mode Control with Extended State Observer Applied for Linear Metro

In this paper, a terminal sliding-mode (TSM) speed regulation algorithm is proposed to enhance the transient characteristics of the linear induction motor (LIM) drive system. Moreover, an extended load thrust observer (ELTO) has been designed to recompense the proposed TSM speed controller at load perturbations or any uncertain condition. The proposed TSM speed controller with ESLTO has combined the direct thrust control with space vector modulation (DTC-SVM) strategy to achieve the speed, electromagnetic thrust, and primary flux-linkage tracking objectives under different operating conditions. The proposed control strategy, (TSMC-DTC), can get a good transient response with a high-speed tracking accuracy as compared to the linear DTC (PI-DTC) and the conventional sliding mode DTC (CSMC-DTC) strategies. Comparative results ensure that the suggested control method has fast speed response, less steady-state error and better steady-state behavior in comparison to those of the traditional control strategies.