An Isolated Bidirectional DC-DC Soft Switching Converter for Super Capacitor Based Energy Storage Systems

In recent years, power electronic energy storage systems using super capacitor bank have been widely studied and developed for the electronic vehicles. In this paper, a full-bridge/centertapped push-pull circuit with active clamp-based soft switching bidirectional DC-DC converter and its control method are presented and discussed. From the results of basic experimental demonstration, the proposed system is able to perform adequate charging and discharging operation between low- voltage high-current super capacitor side and high-voltage low-current side with drive train and main battery. In addition, RCDi snubber losses appeared in the basic circuit topology are drastically reduced by ZCS/ZVS operation with the assistance of newly added active clump circuit, as well as ZVS operation with lossless snubber capacitor in high-voltage primary side.