SRM Sensorless Control Based On High Frequency Pulse Injection And Torque Distribution Strategy

Compared with the traditional motor,the double salient switched reluctance motor(SRM)has the advantages of simple structure,firmness and high reliability.It is suitable for the harsh working condition,such as high temperature and high pollution.However,the operation of SRM depends too much on precise position signal by the sensor and has large torque ripple during the operation.It is of great significance to study the control system of SRM with high reliability,low cost and stable output torque to broaden its application ranges.In this dissertation,a new sensorless control method for SRM based on high frequency pulse injection and torque distribution strategy is proposed.The method is to solve the problem that SRM is over dependent on sensors to provide precise position signals and is prone to have large torque ripple during operation.Firstly,the structure and operation principle of SRM are introduced,three mathematical models of SRM is deduced in sequence.This dissretaion introduces the advantages and disadvantages of classic control modes of SRM,and analyzes control modes combined with the operation characteristics of the motor.Secondly,a sensorless control method of SRM based on high frequency pulse injection and torque distribution strategy is studied.The principle of high frequency pulse injection and torque distribution function are studied.The selection of pulse frequency and the design of pulse distribution function are analyzed.On the basis of theoretical analysis,the system block diagram of the control method in this dissertation is constructed.Finally,based on a switched reluctance motor with a rated power of 1k W,the simulation model and experimental platform are built,and the simulation analysis and experimental research on the proposed method are carried out.Simulation analysis and experimental result shows that the high frequency pulse method can accurately estimate real-time rotor position of the motor,and make the motor run in the zero low speed zone;combined with the torque distribution strategy,it can effectively reduce the torque ripple of the motor output without affecting estimation;the proposed hybrid control method realizes the sensorless torque ripple suppression when SRM operates at low speed.