Predictive Current Control For Permanent Magnet Linear Synchronous Motor

In the field of high-precision AC speed regulation,permanent magnet linear synchronous motor(PMLSM)has become a research hotspot in recent years due to its advantages such as low loss,high thrust strength and fast response.As the inner loop,the current loop is the central link between the control unit and the linear motor.In order to obtain a higher speed loop bandwidth and improve the tracking accuracy of the control system,the current closed-loop system with high bandwidth is the basis for obtaining precise motion.In addition,permanent magnet linear synchronous motor is a kind of nonlinear and strongly coupled controlled object.Since there is no buffering of the intermediate link,the external disturbance will directly act on the motor,which will have a great influence on the control performance of permanent magnet linear synchronous motor.Therefore,a robust current control strategy is critical to high precision permanent magnet linear synchronous motor control systems.Predictive current control(PCC)has become a research hotspot in permanent magnet linear synchronous motor control systems due to its excellent transient performance.However,predictive current control also has problems.Its control accuracy is easily affected by the model parameter of motor,and the control precision is low or the system is unstable in the case of model mismatch and parameter perturbation.According to the above problem,this paper studies predictive current control for permanent magnet linear synchronous motor based on internal model disturbance observer(IMDO).Firstly,the mathematical model of permanent magnet linear synchronous motor,the coordinate transformation method and the basic idea of vector control system are introduced.Secondly,for the predictive current control method,the control law and controller design are elaborated,and the stable parameter range is obtained.When the model mismatch or parameter perturbation occurs,the control effect of the predic tive curre nt control is weakened.Therefore,the principle and design idea of the internal model disturbance observer are introduced in detail,and the discrete internal model disturbance observer is obtained through calculation which can be used in digital control systems to achieve observation and compensation of system disturbances.Finally,the Matlab/Simulink software is used to simulate the predictive current control method based on the internal model disturbance observer.The experimental results of the proposed algorithm are verified on the experimental platform of the AC motor control system Simulation and experimental results show the correctness and effectiveness of the algorithm studied in this paper.