Research On Compound Fuzzy PI Control And Torque Ripple Minimization Of Switched Reluctance Motors

Switched reluctance motor (SRM) has a simple structure, high reliability, wide-speed range, large starting torque, and many other merits. Due to its excellent inherent advantages, SRM has been widely applied in the aerospace, textile machinery, electric vehicles, elevator system and other fields. However, due to the motor's doubly salient structure and impulse power supply manner, which cause relatively large torque ripple and noise, the applications of SRMs are influenced.This thesis aims to analysis, design and manufacture a three-phase 12 stator poles and 8 rotor poles SRM drive system for the high voltage elevator systems. Based on the comprehensive research on conventional SRMs, a novel control strategy is proposed and analyzed in detail, named as compound fuzzy control based on torque sharing function (CF-TSF) for the sake of torque ripple minimization and enhancing transient performances. Also the experimental validations are included. In general, the work of this thesis lays the theoretical foundation for the further research and practical applications of CF-TSF.The main research contents of this thesis can be summarized as follows:(1) The research background, significance of the project and structure characteristics of SRM are introduced. The working principle and mathematical model of the SRMs are analyzed systematically. Then, the different methods of torque ripple minimization are stated and analyzed.(2) Through the analysis of the mathematical model and the control principle of SRM, a simulation model of the SRM drive system is established based on the MATLAB/Simulink. Then, based on the Simulink model, the algorithm of CF-TSF is proposed. Finally, the static and dynamic performances of the SRM drive system are conducted.(3) The hardware of the SRM drive system is designed and implemented, which includes the central controller, current sampling circuit, the position detection circuit, the protection circuits of over-current and temperature, the power supply circuit and the driving circuit of power devices.(4) The software of the SRM drive system is designed and implemented as well. Firstly, the completed software program flow is established. Then, the software is programmed, decoded and co-operated with the hardware.(5) In order to verify the validity of CF-TSF, a three-phase SRM is manufactured, and an experimental platform of the SRM is producted. Then, the static characteristics of the SRM are tested. Finally, a series of experiments are carried out under novel and convential control strategies to verify the theory and the simulation.