Design Of DC Speed Control System For Electromobile Based On DSP

In the recent years,as people are gradually awareness of protecting the ecological environment,the electric vehicles has been rapid developed. Electric vehicles use electric current,batteries or solar energy as an energy source,and these sources does not produce any toxic exhaust,so it plays a big role in the environmental protection. Nowadays, with the continuous improvement of people's living standards,it has emerged small electric cars such as tourism vehicles,that people go to leisure or sightseeing.At the same time,as tour vehicles based on batteries are environmentally friendly,without emission,low noise,simple operation,lower cost maintenance and so on,it's used in an increasingly wide range. So we believe electromobile will be widely used in the future.The study of this thesis is a small electric vehicle.It requires higher starting torque and stable speed adjustment. In the beginning,the thesis chooses a right motor according to the characteristics of motor in different ways of electrical excitation.Then the thesis designs a digital double closed-loop controller of the electric vehicle,and presents a control algorithm of the digital PI controller. And then the hardware and software of the DC motor speed systerm is discussed in this thesis.In the end,the thesis simulates the motor by fuzzy control,with the Simulink module of Matlab.This thesis uses a digital signal processor TMS320LF2407 as a master controller. The armature is controlled with full bridge of four quadrant,and the output or turn-off of PWM signal is controlled by the power driver IC IR2110.In this way,the speed of DC motor can be controlled effectively.The coil of DC motor is controlled by half-bridge circuit,in order to make motor transfer or reverse. It also designes the energy feedback circuit when the electric vehicles brakes in the primary circuit of PWM output. The hardware design includes Power converting circuits, driving circuits, speed detection circuits,current sampling circuits, motor speed control circuit, and system protection circuit.In the software design,the thesis should include those function:1.make the motor transfer or reverse;2.measuring the current of motor and calculate the speed of motor;3.achieve the speed and current dual-loop feedback control of motor by PID regulator. The thesis includes the initialization module, Start-stop module, and A/D interrupting service module.At the end of this thesis, it designs a fuzzy PI control of DC motor driving system,including electrical modeling,simulation of fuzzy control and design of fuzzy rules,and it carries out simulation of the motor in fuzzy control and PID control respectively.By comparing the experimental results,we get a conclusion that fuzzy control has more favorable response characteristics of the motor control.