Investigation of Zero Voltage Switching Capability for Bidirectional Series Resonant Converter Using Phase-Shift Modulation

A series resonant converter (SRC) using a phase-shift modulation (PSM) was invented to implement the bidirectional power flow. However, it has a narrow zero voltage switching (ZVS) range, which reduces the power conversion efficiency for the light load condition. In this paper, the ZVS condition of the SRC is analyzed according to the power flow directions. From this analysis, the SRC using an extended PSM and single PSM is proposed to obtain the soft switching for the entire load range. The analysis of ZVS condition and performance of proposed control algorithm are verified using simulation and experimental results with a 500-W prototype converter.