Robust Adaptive Terminal Reaching Law-Based Sliding Mode Direct Thrust Control for LIM Adapted to Urban Transportation

In this article, a robust adaptive terminal reaching law (ATRL)-based improved terminal sliding mode control (ITSMC) under direct thrust control (DTC) (ATRL-based ITSMC-DTC) method is proposed for the linear induction machine (LIM) drive system. First, the ITSMC is designed from the conventional TSMC to achieve smoother performance under a steady state. Second, the ATRL-based ITSM under the DTC strategy is developed for speed control to achieve faster dynamic response with stronger robustness against load disturbances, smaller tracking error than the conventional DTC (CDTC), and TSMC-DTC of the LIM drive system. Subsequently, the proposed method has been carefully developed to guarantee that the implementation process is thoroughly examined and the stability of the closed-loop system is verified using the Lyapunov candidate. Finally, the simulation and experimental analysis have been conducted on a prototyped 3-kW arc induction machine. This analysis involved three different dynamic working scenarios: start-up response, speed change response, and load change response. A full simulation and experimental comparison of the three methods clearly confirmed that the proposed method is superior in terms of faster dynamic response, lower tracking error, and better anti-disturbance ability than the two other methods.