Hybrid Power Modulation Scheme for High Frequency Isolated Bidirectional Dual-Active-Bridge DC-DC Converter

High frequency isolated bidirectional dual-active-bridge (HFIB-DAB) DC-DC converter is a bidirectional DC-DC converter. A hybrid power modulation scheme is introduced, resulting in improved efficiency over complete power range. This proposed hybrid modulation scheme combines two different types of power modulation techniques. Up to certain level of power modulation, the DPS power modulation technique is more efficient and after that the efficient performance of RF power modulation technique supersedes over the other. A switch over provision is proposed to choose the most efficient one for a given power transfer requirement in the HFIB-DAB DC-DC converter by using the proposed reconfigurable resonant tank network. The results are verified by using 4 kW HFIB-DAB DC-DC converter operating at 50 kHz. It is designed to interface two 400V DC bus voltages on either side of the HFIB-DAB DC-DC converter. The validation is done by using MATLAB/Simulink package and a maximum power transfer efficiency of 99.94% is achieved.