A Non-Isolated Bidirectional DC-DC Converter with High Conversion Ratio

In this paper, a non-isolated bidirectional dc-dc converter with a high voltage conversion ratio is implemented by using coupled inductor and switched capacitor. The voltage stress on the switch can be reduced by a clamped circuit, and the leakage energy is recycled. Moreover, the conduction losses and current ripple can be significantly reduced to improve the system efficiency in stepup stage because of two continuous current paths. A prototype with low voltage side voltage of 48–60 V, high voltage side voltage of 400 V, and rated power of 1 kW is built to verify the performance. The maximum efficiency and full load efficiency are 95.1% and 93.5% in step-up stage, respectively; 95.6% and 94.8% in the step-down stage, respectively.