Main-and-Auxiliary-Currents Diversion (MACD) ZCS Full-Bridge Converter

According to the isolated single-module high-power MV dc/dc converter described in Chap. 1, it can be seen that most the existing topologies can realize ZCS for main switches, but they suffer from issues such as the large number of switches and the difficulty of fabricating high-voltage inductors. To address these challenges, the idea of component multiplexing is used, for example, two switches can be saved by multiplexing a half-bridge circuit. In addition, by integrating the structural features of the single-active-bridge (SAB) converter that contains only the primary-side LV inductor, the use of high-voltage inductors can be avoided. Based on the above two points, this chapter proposes an main-and-auxiliary-currents diversion (MACD) ZCS full-bridge (FB) converter with an output capacitive filter. This converter requires only six switches to form two full-bridge cells and maintains ZCS for main switches. In this chapter, the operation principle of the converter, the soft-switching characteristics, and the design methodology of the main parameters such as transformer turns ratio will be described in detail. Simulations and experimental validations are also presented.