Research On The Torque Ripple Minimization Of Switched Reluctance Motor

Switched reluctance machines (SRM) have been a hot research focus of motor drive field in recent years. SRM has got many outstanding features, such as low costs, simple structures, high efficiency, etc.As a nonlinear and highly coupled system, it is hard to make full use of its advantages using conventional control technologys. Torque ripple of SRM is one of the main disadvantages that cannot be overlooked, and can cause speed ripple and loud noise, so it is necessary to reduce ripple.This research mainly concentrated on the restrain of torque ripple, and it analyzed reasons of torque ripple and researched control strategies for restraining torque ripple in the current academic circles, and then determined the control strategy adopted in this paper. It used DTC to restrain the torque ripple, which is widely used in AC drive, and it also chose the voltage vectors to control based on the SRM characters. DTC can effectively reduce the fluctuation of torque which proved by the simulation using Matlab/Simulink. But DTC of SRM produced pretty large negative torque during roration. This would restrict the application of DTC.On the basis of DTC, the Direct Instantaneous Torque Control (DITC) takes turn-on and turn-off angle into consideration to reduce the negative torque. It controlled torque directly using different hysteresis torque controller.The test platform was established, whose drive unit used a 1.5kW 12/8 SRM. It applied asymmetry half bridge structure, and TMS320F28335 was adopted to process the control. At last, the performance of SRM and the results of experiments which based on DITC were given.