Study On The Control System Of Brushless Direct Current Motor For Electric Vehicles Based On DSP

The control system of drive motor is the "heart" of pure electric vehicles. To a great extent, it determines the performance of pure electric vehicles. Brushless direct current motor is characterized by reliable-operation and excellent property of speed adjustment. Its potential is tremendous working as drive motor in pure electric vehicles. Therefore, studying on control system of motor drive possesses great theoretical significance and practical application value. Traditional speed control system using single closed-loop causes serious oscillation and overshoot. Aiming at the problems existing in single closed-loop control system of brushless DC motor, employing TMS320F28335 control chip for the foundation, this thesis researches the control system of brushless DC motor (BLDCM).The main research works are as follows:(1)Combined with requirements of pure electric vehicle for power characteristics of drive system, by analyzing the structure and working principle of brushless DC motor, the strategy of speed and current double closed-loop PI control and the technology of PWM speed adjustment based on DSP were adopted to research control system of brushless DC motor.(2)Based on the simplified mathematical model of brushless DC motor, taking MATLAB/Simulink as platform, the dynamic simulation model was built. The simulation results showed the feasibility of double closed-loop PI control strategy, provided theoretical support for the hardware design of the system.(3)The hardware of drive control system for brushless DC motor in pure electric vehicles was studied and designed. Employing TMS320F28335 for core control chip, integrated chip IR2130 for drive chip, the DSP control circuit and the peripheral circuit were designed.(4)Based on the modularized program structure, each program module was completed by C language in integrated development environment CCS3.3.Analysis results of dynamic simulation verified the effectiveness of double closed-loop PI control strategy adopted.Verification experiment results showed the feasibility of the controller designed for Brushless DC Motor used in pure electric vehicles. This research possesses certain reference value for the research and development of high-performance control system for Brushless DC motor used in pure electric vehicle.