High Efficiency and Voltage Conversion Ratio Bidirectional Isolated DC-DC Converter for Energy Storage System

This paper proposes a high efficiency and conversion ratio bidirectional isolated DC-DC converter with three-winding coupled inductor, which can fulfil storage system charging discharging. The proposed topology is improved from traditional Buck-Boost converter. By integrating inductor switched-capacitor into power stage, the achieve merits of isolation flow. has only four switches common core greatly reduces design costs achieves step-up/step-down voltage gain without excessive duty cycles or turns ratios. In addition, also function leakage inductance energy recovery, recover all stored in to improve efficiency, main zero switching (ZVS) feature. implements 500 W verify feasibility through software simulation experiment results, conducts theoretical analysis, formula derivation, operation principle non-ideal analysis. Finally, experimental results show that highest step-up step-down modes are 96.8% 96.4%, respectively.