Research On Brushless DC Motor Control System Based On DSP

In the fields of ship manufacturing,textile machinery,medical devices and electric vehicles,brushless DC motor has been widely used because of its clear structure and high efficiency.It has replaced the brush DC motor with mechanical friction,noise interference and other defects in the commutation process.As the application fields of brushless DC motor is expanding day by day,the requirements for the control system of brushless DC motor are getting higher and higher.Therefore,it is necessary to study the control of brushless DC motor.Based on the discussion of the basic components and working principles of brushless DC motor,this thesis models the brushless DC motor.This thesis analyzes and studies the control system of brushless DC motor,using double closed loop control structure,current loop using PI control,speed loop using fuzzy PI control method.Through the research of fuzzy control method,and then design the fuzzy PI speed controller,and use Matlab software to build the fuzzy PI controller.In this thesis,a brushless DC motor control system model is built on Matlab/Simulink simulation platform.The simulation models include speed model,current model,commutation model and sampling model.Under this system,the speed simulation experiments based on no-load and load are carried out for PID control and fuzzy PI control respectively.The simulation results show that the fuzzy PI control system has better stability than the PID control system.On the basis of simulation verification,the hardware circuit of brushless DC motor based on TMS320F28335 is built,and the control system software is designed at the same time.Finally,relevant experiments are carried out to verify the experimental circuit.the experimental results verify the feasibility of the brushless DC motor system designed in this thesis based on fuzzy PI control.