Fuzzy adaptive sliding mode decoupling control of permanent magnet linear synchronous motor

When the permanent magnet linear synchronous motor servo system works in the field of high speed and high precision, the dynamic processes of motor current and velocity are relatively close to each other in time scale. The nonlinear coupling and load disturbance are the key problems which affect the tracking accuracy. In this paper, the nonlinear model of the motor is established and decoupled by state feedback linearization. The independent current subsystem and linear speed subsystem are derived. In order to reduce the dependence of feedback linearization control on linear motor model and improve the robustness of servo system, a sliding mode controller is designed. The fuzzy adaptive control method is used to estimate the system uncertainty, replace the switching control and load disturbance in sliding mode control, and reduce the system chattering. The stability of the closed-loop system is proved by Lyapunov theory. The experimental results show that the control strategy has stronger robustness, better adaptive ability, and higher control accuracy.