Bidirectional Converter System in Dual Active Bridge Topology for a Hydrogen Tank

The paper presents a Dual Active Bridge (DAB) converter operating as an interface between the LiFePo4 battery and the fuel cell/hydrogen generator. The hydrogen tank can increase the stored energy of the battery system. Among the main requirements for a converter is the need to transfer power of up to 10 kW and operate with widely changing voltages on both sides of the converter. The design of the power electronic part and passive components of the converter is deeply discussed. Next, the influence of the wide voltage range on the operation of the converter is depicted, including its impact on power losses and current values. Different topological modifications for power loss reduction are presented and experimentally verified. Finally, a simple modification of the control system, giving the possibility of increasing efficiency, is briefly presented.