A Family of Bipolar DC–DC Converters With Interpolar Voltage Self-Balancing Based on FB-BVMs for BLVDC Microgrid

Aiming at the problem of interpolar voltage unbalance in bipolar low voltage dc (BLVDC) microgrid, a family of bipolar dc–dc converters with interpolar voltage self-balancing is proposed in this article. The proposed converters are composed of a full bridge inverter and four types of bipolar voltage multiplier (BVM) circuits. Benefiting from the characteristics of the proposed topology, its output power can automatically flow to the output side with lower voltage and has the ability to maintain the voltage balance between BLVDC buses. In addition, the proposed converters have ZVZCS soft-switching characteristics, and the control and driving circuits are consistent with the traditional full bridge inverter. The topology derivation, working principle, soft-switching and voltage self-balancing performances of the proposed converter are analyzed, and a 1 kW experimental prototype with its control system is designed. The experimental results verify the accuracy of the theory and analysis.