Research On Suppression Strategy Based On Thrust Ripple In Permanent Magnet Synchronous Linear Motor

Compared with the permanent magnet linear synchronous motor and thetraditional “roller screw and rotary motor”, it has the Advantages of high efficiency, simplestructure. Therefore, it plays a significant role in modern processing, automatic control systemof high speed and high precision and other cutting-edge fields. The methods of suppressingforce ripple of PMSLM are crucial problems.In this paper, the thrust ripple of PMSLM as the research subject, is caused by edge effectbecause of the discontinuity of on-off armature core, the cogging force caused by settingthe cogging structure in the core for the storage of windings and the external disturbingforce and many reasons. This paper makes analysis and research, basing on it, and put forwardthe corresponding improvement strategy.First, this paper involves the permanent magnet linear synchronous motor designstructure and its basic working principle, and analyzes the main reasons of force ripple ofPMSLM in details, and point out that detent force is the important part. The finite elementmodel of the PMSLM is established by Ansoft, and improving the structure parameters tosuppress detent force. the simulation analysis, we can conclude that it is useful to cut detentforce to increase arc coefficient、reduce the width of tooth mouth and the height of end tooth.Secondly, to analysis of PMSLM, its mathematical model of d-q axis after the decouplingis set up. And the space vector pulse width modulation technology of PMSLM is introduced indetail. According to the principle, build the simulation system using MATLAB/SIMULINK.Using the method of finit element analysis,the detent force and friction force curve are known,disturbance observer and feedback compensation device are designed. Disturbance observerobserved changes of load force in real time, in which the disturbance was equivalent to corresponding current inputs to the system. Comparing with no compensation improvementmethods, the final results tell that the proposed method effectively reduces thethrust disturbance.Finally, to further suppress the force ripple and improve the performance of the linearmotor, fuzzy PID controller is added in Speed control links. Based on disturbance observer,Fuzzy PID control improves the linear motor of the whole system response time and reducedthe amount of overshoot, making Linear motor to achieve faster movement balance. Throughthe simulation experiments analysis, Results illustrate that the Fuzzy PID control based ondisturbance observer is effective and further optimization of the dynamic and staticperformance of the system, and the stronger robustness.