Research On Disturbance Rejection Strategy Of Permanent Magnet Linear Synchronous Motor Drive Control System

Permanent Magnet Linear Synchronous Motor(PMLSM)adopts a direct drive mode to drive the motion actuator directly,which can effectively improve the transmission stiffness and efficiency of the system and achieve "zero transmission" of the feed system by eliminating intermediate transmission links.Therefore,linear motors using direct drive transmission mode have been widely used in the field of industrial automation.However,PMLSM is susceptible to parameter perturbations,thrust fluctuations,and other uncertain factors during operation.In order to improve the control performance of PMLSM,this article analyzes the generation mechanisms of various types of disturbances in PMLSM,and designs control strategies with strong disturbance suppression performance to improve the velocity stability and positioning accuracy of linear motors.As the innermost loop of the drive control system,the control performance of the current loop directly determines the quality of the output thrust.Aiming at the disturbance problems such as the cross coupling of the d and q axis currents and parameter perturbation,a fully decoupled linear active disturbance rejection control strategy is used to decouple the PMLSM current loop.The system parameter setting process is further simplified by decoupling the disturbance suppression performance and tracking performance of the controller.Finally,the effectiveness of fully decoupled linear active disturbance rejection controller is verified by simulation and experiment.The detent force is the main reason for the thrust ripple of linear motor.The detent force model obtained by finite element simulation is taken as the known disturbance of the system,and other unknown disturbances are extended as the state variables of the system to construct the extended state space expression of PMLSM.Based on the extended state equation of the system,the PMLSM velocity-ring sliding mode-active disturbance rejection composite controller is designed.The non-singular fast terminal sliding mode control with variable coefficient double power reaching law can realize the global fast convergence of the system state.The super-twisting sliding mode observer is constructed to observe the lumped disturbance of the system and perform real-time feedforward compensation.Finally,simulation and experiments prove that the sliding mode active disturbance rejection controller can effectively reduce the adverse effects of thrust fluctuations in linear motors and improve the dynamic response speed and velocity smoothness of linear motors.For the trajectory tracking control of linear motor reciprocating motion,a secondorder nonsingular fast terminal sliding mode control based on the super spiral algorithm is designed using a PMLSM position current double closed-loop control system,which reduces the chattering problem of traditional sliding mode control.In order to solve the problem of increasing position error caused by friction discontinuity during steering of linear motor,an adaptive algorithm is used to adjust the sliding mode control gain online,which improves the control accuracy of the system and overcomes the localization of the need to determine the disturbance boundary for sliding mode control to suppress disturbances.Finally,simulation and experiments verify the effectiveness of the adaptive hyper spiral algorithm.This article has 61 figures,3 tables,and 95 references.