A high-gain bidirectional buck-boost converter with reduced input ripple for hydrogen–battery hybrid energy systems

This paper proposes a high-gain, efficient and cost-effective bidirectional buck-boost converter suitable for grid-connected hybrid hydrogen-battery renewable energy systems. The proposed topology employs a switched-inductor cell composed of two input inductors and three switching devices which significantly reduces input current ripple and improves voltage gain. The converter consists of seven bidirectional switching devices, three inductors and three capacitors while maintaining a relatively simple control structure. For applications where high gain is not required, the topology can be simplified by replacing the switched-inductor cell with a single inductor resulting in a lower-cost and simpler configuration. Mathematical analysis of the converter operation is presented to derive voltage gain characteristics and operating principles. The effectiveness of the proposed topology is validated through experimental results which confirm its high efficiency, reduced input ripple and suitability for hybrid renewable energy applications.