The Design Of Electric Vehicle Charging System And The Research Of Its Intelligent Control Strategy

Electric vehicle uses all or part of electricity as drive system power source, which does not cause the fuel problem and automobile exhaust emissions and occupies distinct advantage in terms of environmental protection, clean, energy-saving. Nowadays, the research and development of electric vehicle has become the hot spots of the world. But few studies on the charger and electric vehicles energy supply system are taken, there are a number of theoretical and technical problems yet to be research. Because the development of the charger can not meet the requirements of the electric vehicle, the development and popularization of electric vehicles has been seriously hampered. A large number of model theoretical and experimental research on the method of charging and charge control strategy at home and abroad indicate that the conventional charging methods and a single control strategy also has some obvious shortcomings. The combination of the conventional PID control and fuzzy control method not only make the system dynamic response curve is better, less overshoot, faster response, but also make the system can be quickly restored when the steady-state encounter interference, which is significantly better than the conventional PID control method.To this end, the paper uses TI’s TMS320F28335as the master chip, uses a variety of charging methods, PID control and fuzzy control method to study on-board charging system and its intelligent control strategy. The main innovation and research work are as follows:(1)This part of the paper designs the charging system hardware and software. In order to overcome the shortcomings of traditional hard-switching, the system uses a zero-voltage zero-current phase shift full-bridge soft switching circuit, which can realize zero-current switching of hysteresis arm and zero-voltage switching of forearm. This can greatly reduce the power loss of the switch, at the same time it has a switching device withstand voltage, capability of through strong current and high utilization of the power transformer. In order to ensure the stability of the system this paper uses a high-precision power chip TPS62143. In order to achieve a different system interface compatibility, CAN, RS232and RS422communication interfaces are designed.(2) Fuzzy Adaptive PID control strategy for electric vehicle charging system is studied and a fuzzy adaptive PID controller is also designed in this paper. Simulation results show that this control method taking into account the advantages of fuzzy control and conventional PID control, has a strong adaptability and better robustne. Especially, when the system parameters change this controller can still get very good control effect.(3)this paper also study the the application of electric vehicle car charging system. In order to solve the non-linear of sensor signals, non-linear processing function algorithm, variable voltage source bridge method and the non-linear compensation are sdopted in this paper. A Matlab simulation model of charging system is builded according to the system design requirement and the simulation results can be very good to achieve the desired design requirements.