Research And Application On Speed Control System Of PMSM Based On Sliding Mode Controller

Permanent magnet synchronous motor has the advantages of small size, simple structure,high efficiency. So permanent magnet synchronous motor speed control system is more andmore widely used in aerospace, CNC machine tools, industrial robots, military weapons andother advanced technical fields in recent years. In Traditional speed control system ofpermanent magnet synchronous motor, the speed closed-loop and the current closed-loopoften adopted traditional PI controller. The permanent magnet synchronous motor is anonlinear and time-varying system, but PI controller is essentially a linear controller. At thesame time the PI controller is sensitive to parameters of system. So based on the traditional PIcontroller of permanent magnet synchronous motor speed control system can’t meet therequirements of high precision speed control. Sliding mode control is a kind of nonlinearcontrol, it has some advantages such as good robustness, fast response speed and easy toimplement, etc. Therefore, to achieve a better performance of speed control system, slidingmode control was applied to permanent magnet synchronous motor speed control system andused it to instead of PI controller in speed loop in this article.Based on the analysis of permanent magnet synchronous motor vector control, thesimulation study of traditional PI control system is done by Matlab/Simulink. PI controllerperformance is stdudied by simulation. For disadvantages of PI controller performance, thesystem introduced sliding mode controller to instead of PI speed loop controller. At the sametime, the integral term is introduced to sliding mode control switching function, whichbuilding integral sliding mode controller. The simulation results show that the speed controlsystem based on integral sliding mode controller take less time to reach the given speed andhas smaller overshoot.For the chattering problem of sliding mode control, this paper proposes two improvedschemes. One improved scheme is integral sliding mode control scheme based on the newreaching law and the other one is the improved integral fuzzy sliding mode control. Thesimulation results show that these two kinds of improved scheme can improve theperformance of sliding mode control. At the end of the paper, some research achievements ofsliding mode control are applied to the speed control system of pure electric vehicle.