Design Of Power Supply For Electric Vehicle Based On Soft-switch Full Bridge Converter

In present times, energy crisis and environmental pollution are increasingly serious. Air pollution caused by motor vehicle exhausts accounts for a large proportion in urban air pollution. However, electric vehicle as a non-polluting transportation tool, will have great advantages in the market, meanwhile, the charging technology for electric vehicle is also constantly and continuously improved and optimized. As 2008 Olympics is approaching, China will utilize electric vehicles extensively in Beijing such as in the Olympic village to make the 2008 Beijing Olympic Games a real Green Olympic Games. Under this background, the thesis intends to research and systemically design power supply for charging up the electric vehicles, presents a charging power supply system, of which the main circuit topology is a zero-voltage and zero-current (ZVZCS) full-bridge converter topology, resulting in a relatively high power factor and high efficiency charging equipment. Firstly, the thesis summarizes the present research situation of the charger and charge control strategy, then comparatively studies a variety of soft-switching full bridge topology, and finally selects a novel zero-voltage and zero-current-switching full-bridge converter using a simple auxiliary circuit. The simple auxiliary circuit, which consists of one small capacitor and two small diodes, is added in the secondary. The simple auxiliary circuit, which consists of one small capacitor and two small diodes, is added in the secondary. The auxiliary circuit includes neither lossy components nor additional active switches, its structure and control method is simple. It can provide ZVZCS conditions to primary switches, as well as to clamp secondary rectifier voltage. Based on the premise of the reliability of power supply, its parameters were design and compute. In addition, since the converter's leading leg switches' ZVS cannot be realized in the light load period, the novel ZVZCS full bridge converter was improved. Finally, it achieved soft-switch in its all load range. The results of the experiment validate the feasibility of using the topology in electric vehicle charger.