Research On Switched Reluctance Motor Back Stepping Control Method

Switched reluctance motor(SRM) get many people’s recognition and application as a new type of speed control system since its advent for its simple structure, low cost, high efficiency.SRM has been successfully applied in the electric vehicle drive system, household appliances, industrial application, servo system, high speed driver, aerospace and many other fields. It’s a strong competitor against other speed control systems, such as ac motor, dc motor and brushless dc motor.SRM’s torque ripple and noise problems caused by its inherent doubly salient structure limits its application in many sophisticated occasions. SRM is a multivariable,nonlinear and strong coupling system because of its special structure and saturated magnetic circuit. There are many control methods to reduce the torque ripple, such as linear control, variable structure, iterative learning and intelligent control theory. The paper proposes Back-stepping control(BSC) on the three-phase 6/4 SRM, that is to apply the BSC respectively to speed, torque and magnetic link. The main work is as follows:First, learn to know the BSC principle and find out the characteristics the BSC applied in the general nonlinear and strong coupling systems, Analyzing the feasibility of BSC implying to the SRM system. Secondly, find out the differences among linear model, quasi linear model and nonlinear model, chose the quasi linear model as the basis of BSC. Then set up the BSC model of the SRM which according to designing the speed controller, torque and flux controller. Connect these controllers as speed and flux loop which help to doubly control the motor. Finally, choice the voltage PWM controller according to the voltage value given by the speed loop, the current chopper controller according to the given current value by the flux loop, so the BSC of SRM is completed.Respectively create the BSC controller, Current- chopping ontroller and Direct Torque controller with the MATLAB simulation module. The comparison of the simulation results of these controllers indicate that this scheme has strong robust and can effectively reduce the torque, flux and current ripple, which is consistent with the expected results. The study of this paper is of great significance for popularizing the SRM.