Research On The Motor Control System Of Electric Vehicle

Under the pressure of the increasingly serious environmental pollution and theenergy crisis, the research and development of electric vehicle is an important directionof the green and sustainable development of the global automotive industry. There aremany factors restricting the development of the electric vehicle and the drive system ofelectric vehicle is one of the important reasons. The performance of driven systemdirectly affects the performance and efficiency of electric vehicles, therefore, researchingand developing high performance speed control system of motor is the key issues ofelectric vehicles. The brushless DC motor (BLDCM) is widely used in electric vehiclebecause of its high efficiency, high torque, wide speed range, low-speed performance,high power density, easy to control, safe, reliable, low noise, etc.In this paper, the BLDCM driven system is designed for the electric vehicle. TheSTM32F103(32bit) microcontroller with ARM cortex-M3core is used as the corecontroller in this system. And the Active-Disturbance-Rejection controller is used in thesystem for think of the operational features of electric vehicles. In order to improve thereliability and reduce the costs of the system, the sensorless control technology is use toget the rotor position. The control effects of ADRC and sensorless design are given basedon Matlab/Simulink simulation.In this paper, firstly, the structural characteristics and working principle of theBLDCM is described and the mathematical model and operating characteristics areanalyzed in detail. Secondly, the ADRC is applied to the control system to improve thedynamic performance and the robustness of the system. The BLDCM controller forelectric vehicle based on ADRC is designed after analyzing the principle of ADRC andthe simulation model is made in Matlab/Simulink. The control effect of ADRC iscompared to the effect of PID controller and the simulation results show that the ADRChas great dynamic performance and robustness. The BLDCM must rely on the positionsensor to obtain the rotor position signals, but the existence of the sensor making thesystem unreliable, poor performance and high cost, therefore, this article uses sensorlesstechnology to detect the rotor position. Finally, the hardware of BLDCM control systemfor electric vehicle based on STM32F103and the software are designed, including themain circuit, driven circuit, protection circuit and detection circuit and the software of theprincipal modules. Experimental test is taken to the system, and the experimental dataand problems in test are analyzed. There are some recommendations for follow-up studyof BLDCM driven system for electric vehicle in this paper.The simulation results and the experimental results show that the BLDCM drivensystem for EV based on ADRC designed in this article has great adaptability androbustness to uncertain and large change disturbance. The control system is highreal-time performance and high reliability.