IJCAS

For four-PMSM synchronization systems, the complex structure, nonlinearities and uncertainties make accurate modeling and precise control difficult to realize. This article proposes an easily realized adaptive control scheme for four-PMSM synchronization system. This control scheme combines novel characteristic modeling, genetic algorithm and terminal sliding mode control together. Firstly, the four-PMSM synchronization system is described by characteristic model, which significantly simplifies system’s dynamic model without losing its highorder characteristics. Secondly, a genetic algorithm estimator is newly designed to estimate the real-time value of parameters in characteristic model, which is the key issue in obtaining an accurate system model. Thirdly, an adaptive discrete-time terminal sliding mode controller is proposed based on the characteristic model to enhance system robustness. Also, this controller can eliminate chattering effect when system is reversing. Then, the stability of the closed-loop system is proved by Lyapunov stability theorem. Finally, simulation and experiment results verify the adaptiveness and robustness of the proposed control scheme.

Keywords: Adaptive control scheme, characteristic model, four-PMSM servo system, genetic algorithm estimator, terminal sliding mode control.