A DC-DC converter with input full active bridge and output semi active bridge for bipolar LVDC systems

A bipolar topology with multi-mode operation capability is proposed in this paper as an interface DC-DC converter for critical loads in bipolar low voltage direct current (LVDC) systems, which can operate under either bipolar-input mode or monopolar-input mode. The proposed converter consists of two full active bridges (FAB) at the bipolar side and one semi active bridge (SAB) at the load side. Zero voltage switching (ZVS) zone for the two operation modes are inspected to provide reference for parameter selection. With a proper parameter selection, the proposed converter could realize ZVS turn-on of all active switches under both operation modes while remaining an unchanged output power in steady state. The proposed converter and is verified with PLECS simulation.