Research And Development Of Brushless DC Motor Controller And Control Strategy For Electric Vehicles

Driving and controlling system of motor is one of the key technologies for electric vehicle (EV). Brushless DC motor (BLDCM) is becoming a hotspot to research in recent years. With the rapid development of semiconductor devices and electronics, BLDCMs are widely applied. Rare earth materials are used in the motor rotor, which optimize the operating characteristics of BLDCM. High-performance microcontroller and DSP are also widely used in the control system of BLDCM. BLDCM is moving in the direction of general interface and digital control system.At present, BLDCM’s controller is used for small power motors, and the developing cycle of controller usually is too long. To solve these problems, a 3kW BLDCM is selected to experiment, and a hardware-in-the-loop simulation platform is designed. The main content of paper as follows.Firstly, several drive motors used in EV are compared and analyzed in this. BLDCM’s working principle and its control strategy are researched and introduced in detail.Secondly, based on the mathematical model of BLDCM, a simulation model is established in Matlab. The dSPACE is a real-time simulation tool, and it is introduced in the paper, including its hardware, software and applications. A rapid control prototype based on dSPACE is designed.Thirdly, discrete components are used in the driving circuit of the control system hardware, and a current sensor named FS025BT is used to detect bus current. The microcontroller XC886 is used in the software system of BLDCM, the dual-loop PI controller is explained indetails in this paper.Fourthly, the experimental results based on the data and waveform shows that control system is feasible and reliable.The controller and inverter of this subject have certain practical value.