Research On Backstepping Control Of Permanent Magnet Linear Synchronous Motor Based On Extended State Observer

In recent years,with the rapid development of high-tech field and the increasingly stringent requirements for product technical indicators to market,the high-end machine tool industry is facing unprecedented challenges.Permanent magnet linear synchronous motor(PMLSM)has gradually become an essential choice in high-end CNC field due to its excellent performance and close structure.PMLSM,which has the characteristics of high order,multivariable and strong coupling,is equivalent to DC motor by vector control technology.It has achieved remarkable achievements in precision manufacturing field.In order to further improve the excellent characteristics of PMSLM,experts and scholars from all over the world have studied PMLSM extensively and put forward many control strategies.Among them,back-stepping control is applied in PMLSM control field because of its excellent control performance,it can make the system stable,but the external disturbance is not considered in the controller design.To solve the above problems,this paper studies a back-stepping control strategy of permanent magnet linear synchronous motor based on extended state observer(ESO).Firstly,the structure,working principle and mathematical model of PMLSM are introduced in detail.The coordinate transformation method which can realize the equivalent transformation of mathematical model from PMLSM to DC motor is explained,so that the flux current component and the thrust current component are completely decoupled.Secondly,taking permanent magnet linear synchronous motor as control object,this paper introduces tlhe research background,basic idea and design schheme of back-stepping control,and proves its stability according to Barbalat lemma.However,it does not consider the influence of load disturbance on the system,an extended state observer is introduced on the basis of detail,as well as the advantages of ESO in PMLSM control system,and analyses its stability.Finally,an experimental platform with TI's DSP chip TMS320F28335 as the core of the controller is built,and the back-stepping control experiment of permanent magnet linear synchronous motor based on extended state observer is realized,and the correctness and validity of the control method studied in this paper are verified.The simulation and experimental results show that the back-stepping control method of PMLSM based on extended state observer effectively improves the rapidity of the system,reduces the influence of load changes on the control performance of the system significantly,improves the steady-state and dynamic performance of the system,and effectively suppresses the thrust fluctuation of PMLSM at low speed.