Design Of Wide Input Voltage DC/DC Converter

With the rapid development of society, traditional fuel vehicles provide the convenience for human life, and also bring environmental pollution and energy crisis. To sovle these problems, people develop electric vehicles and hybrid vehicles. New energy vehicles using electricity as a power give power converters new requirements. This thesis mainly researches the DC/DC auxiliary converter for car charger in new energy vehicles, and a two-stage DC/DC converter is discussed in detail.In this paper, DC/DC chargers are classified by the advantages of various topologies and the applications of DC/DC chargers, and made a conclusion. This thesis focuses on wide input voltage of DC/DC converter, and the ZVS phase-shifted full bridge converter and two-stage interleaved Boost-LLC converter are studied and designed. According to the loss breakdown result, two-stage interleaved Boost-LLC converter is preferred.The principle of two-stage interleaved Boost-LLC is introduced, and the design method of resonant parameters is studied. On the basis of above analysis,a1500W prototype is built. The interleaved Boost stage and LLC stage are tested, and the test results are shown and analyzed, the validity of the design and theory analysis are verified by the experimental results.