Vector Control Of Electric Vehicle Drive System Based On DSP

With the increasing quantity of our country's vehicle, contradiction in supply and demand of traditional vehicle's fuel becomes more obvious. Electric vehicle(EV) uses electricity as its energy source, so EV gives its prominent advantages to zero-let & non-pollution. Foreground of developing & researching electric vehicle is quite amplitude. The hard—core of system of EV is drive and control of motor. Induction motor (IM) is widely used in EV since its simpler construction, small motor size, low maintenance and better reliability. This paper studies the drive and control of motor of EV which is with the high performance microprocessor as the core. It utilizes the vector control theory. Specially, the project develops a new kind of EV drive and control system. Main research achievement is as bellows:The vector control theory and its decoupling are introduced on the foundation of the mathematical model of asynchronous motor. The variables in 2-phase static coordinates are converted into the variables in rotating coordinates and the components between torque and magnetic field of stator winding current are decoupled which uses the rotor-field-oriented technology. Thus, the speed regulating performance of the asynchronous motor is improved highly. The structure diagram of vector control system which combines the current model of motor is given and provides the theoretical basis for the design of vector control system platform.The thesis also introduces calculation of drive and power of induction motor. Based on the factual requirement of EV control, different speed gears and accelerator input are realized. Intimation system is established in the environment of MATLAB to validate these control arithmetic.A 2.2kW squirrel-cage IM is used to verify our method and a system of FOC control is designed. The system is made up of circuit cored around DSP (TMS320LF2407A) and circuit cored around IPM, which realizes function of given speed gear ,given accelerator, detection and communication. By experimentation, the system has proved its good anti-jamming performance and validates credibility of the system.Through the compiled surroundings of CCS, the vector control system of EV isrealized by programming mingled C language and assembly language. The system proved its validity of subprograms which include voltage calculation module, rotor magnetic chain observation module and SVPWM output module.By research of the driving system of EV, the thesis combine the technology of FOC and DSP perfectly, a full digital FOC system is realized. The system proved its enormous practical value of application.