Design Of Switched Reluctance Motor Controller In Low-speed Electric Vehicles

With the shortage of petroleum resources gradually, the blade electric vehicles (BEV) technology has begun to get more and more favour from people. As the power source of Blade Electric Vehicles, the motor and its controller is the main component of the entire BEV. At present, there are many different types of motor speed control systems as the vehicle power, in which the switch reluctance motor(SRM) has simple structure, strong and high efficiency, and high starting torque.etc,thus becoming one of the optimization models. According to the characteristics of drive system of the electric vehicle,this paper makes the elaboration and validation to principle of speed control and the concrete implementation plans of the controller of the SRM.This paper firstly analyzes the background and significance of BEV research, and points out the main deficiency are large torque ripple and the complicated control system when the speed control of switch reluctance motor is applied to BEV. Therefore, the paper puts forward the direct instantaneous torque control strategy which is suitable for vehicle characteristics. Based on the real-time detection to the current, position angle and magnetic chain of the motor, the micro controller estimates the instantaneous torque of the motor, thus to realize the direct torque control to the SR motor. At the same time,in order to achieve good control performance, this paper puts forward the strategy of the fuzzy PID adaptive speed control,and meets the control requirements that the vehicle start-up and shutdown repeatedly.In order to verify the proposed control strategy and the control scheme are reasonable or not, the paper sets up quasi-linear static simulation model for speed control system of the SRM, and the control strategy above are verified.In order to increase the reliability of the vehicle control, the STM32F051micro controller produced by ST company is choosen as the core chip of SRM controller. It has high data processing ability, stable performance, a lot of peripheral ports, and decreases the complexity of the system. Through the digitizing and discretization to the mathematical model of the fuzzy control strategy and instantaneous torque function, the C language are written in the Keil software compiler platform as the system program, so that the mentioned control strategy above is achieved.