Voltage-Balancing Dual-Active-Bridge (VB-DAB) Converter for Bipolar DC Distribution System

This article proposes a new voltage-balancing dual-active-bridge (VB-DAB) converter for the bipolar dc distribution system. The proposed converter comprises the same components as those of the conventional DAB converter, and it integrates functions of a VB without additional components. The proposed converter transmits power using the same principle and control as the conventional DAB converter. Furthermore, it regulates both output voltages equally and redistributes the unbalanced load current. Therefore, the proposed converter neither requires additional components nor results in losses by them. Consequently, it can achieve high efficiency and high power density. The effectiveness of the proposed converter is verified by 3-kW prototypes with a 380-V input and ±190-V outputs conditions.