ABSTRACT:

The aim of this study is to develop a high-efficiency bidirectional dc-dc converter for a power storage system. The proposed converter can boost the voltage of an energy-storage module (e.g. battery) to a high-voltage-side dc bus for the load demand. When the high-voltage-side dc bus has excess energy, this energy-storage module can be charged by the dc bus. In this study, a coupled-inductor bidirectional converter scheme utilises only three power switches with the properties of voltage clamping, synchronous rectification and soft switching. As a result, the objectives of high-voltage gain, high-efficiency power conversion and bidirectional power control can be achieved. Some experimental results via a 48/360 V kW-level prototype are given to verify the effectiveness of the proposed converter in practical applications.