On the Analysis and Design of High-Frequency Transformers for Dual and Triple Active Bridge Converters in More Electric Aircraft

Abstract: DC-DC converters with galvanic isolation are a key element in the aircraft DC distribution system and Dual and Triple Active Bridge converters are one of the most interesting candidates in this application. The high-frequency transformer leakage inductances play a key role in the AC Link of these converters. This leakage inductances determine the power transfer capability of the converter and shape the AC link currents. The leakage inductance value is related to the distribution of the transformer windings and it changes with the RMS value of the AC link current. In this paper, first a high frequency transformer is designed for a Dual and Triple Active Bridge converter for the More Electric Aircraft DC power system. Then, an Ansys/Maxwell Finite Element analysis is performed on the leakage inductances of the transformer in three different winding configurations and in different AC link RMS current values. Finally, the transient performance of the design is validated by the Ansys/Maxwell Transient.