Sensorless Control Of PMLSM Based On Super-twisting Sliding Mode Observer

Permanent magnet linear synchronous motor(PMLSM)has the characteristics of fast dynamic response,high positioning accuracy,and high thrust strength,making it more effective in linear drive system control than the method of connecting rotating motor with ball screw.The accuracy of the real-time position and speed of the mover fed back to the system will directly affect the performance of the PMLSM control system.The usage of the position sensor will increase cost and the system complexity,and limit the application environment of PMLSM.Therefore,the position estimation technology without position sensor is applied to the closed-loop motion control system of PMLSM,which is of great significance.In order to improve the performance of permanent magnet linear synchronous motor sensorless control,this paper studies PMLSM sensorless control method based on super-twisting sliding mode observer(STA-SMO),to overcome the traditional SMO inherent shortcomings of chattering and phase lag.Firstly,the structure,working principle and the mathematical model of PMLSM are introduced.Secondly,the basic idea and the overall scheme of sensorless vector control system based on SMO is introduced.Because of the chattering of SMO,the super-twisting algorithm is combined with the SMO to form STA-SMO,which can effectively improve the sensorless estimation performance and obtain accurate mover position of the PMLSM sensorless control.In order to verify the effectiveness and correctness of the super-twisting sliding mode observer,sensorless vector control system of PMLSM based on STA-SMO is studied and analyzed by Matlab/Simulink.The hardware platform with TMS320F28335 microcontroller is built,SMO and STA-SMO are comparative experiments.Simulation and experimental results confirm the validity and effectiveness of the proposed sliding mode observer.