Zero Voltage Switching Technique for Bi-Directional DC/DC Converters

This paper proposes a zero-voltage switching (ZVS) technique for bi-directional DC/DC converters. The DC/DC unit considered consists of two distinct bi-directional DC/DC cells paralleled at both input and output and whose two input bridges are coupled by means of passive inductive branches. A multi-angle phase-shift modulation method is proposed which simultaneously achieves bi-directional power control, power sharing and ZVS of all the electronic devices over the full power range without the need for auxiliary switches. Simulation and experimental results are reported for a 2.4 kW DC/DC unit consisting of two paralleled 1.2 kW bi-directional Dual-Bridge Series Resonant Converter (DBSRC) cells.