Design And Study On Intelligent Rapid Charger For Electric Vehicle

Electric Vehicle (EV), with its low emission, high efficiency and energy hybridization, is an important way to solve the problems of atmosphere pollution and lack of petroleum resource. The technology of EV develops rapidly, but the state-of-the-art power battery technologies can't meet the requirement. Therefore, an integrated on-board charger, which can charge the battery everywhere to extend the driving range, makes the EV practical.In this paper, the designing of an on-board downsized and lightweight intelligent charger for fast charging is described. The designing process, including the main circuit designing, power device designing and selecting, software system and communication protocol designing, is presented in the paper.High frequency switching mode power supply (SMPS) with half-bridge topology circuit is used in the charger to make the charger lightweight and downsized. For the fast charging strategies such as negative and positive pulse charge, a bidirectional DC-DC converter is designed for the battery discharge and energy recovery. To implement these functions, a bidirectional half-bridge topology circuit is designed after circuit analysis of all kinds of converters. In addition, different charging methods are implemented to meet all kinds of charging strategies and the program charts for each method is given in the paper. The parameters of the program can be set for the charging adjustment. Communication between the charger and the controller is implemented for charging parameter setting, charger controlling and displaying of the charging state.The concrete design of the charger and the charging waveform are presented, which show that the main circuit topology and software system work well, and the designing objective is realized.