A Novel Voltage Balancing Strategy using LC for Dual Output Dual-Active-Bridge Converter

In this paper, a novel voltage balancing strategy (VBS) using one inductor and capacitor (LC) is proposed. The proposed VBS can be applied to dual output dual-active-bridge (DAB) converters such as half-bridge and neutral-point-clamped DAB converters. The dual output DAB converters with the proposed VBS achieve output voltage balancing regardless of output load conditions without additional voltage balancing circuit. Although LC is added between transformer and neutral-point of output capacitors, a conventional pulse-width-modulation scheme can be used and the LC has no significant effect on the operation of the converters. Therefore, the dual output DAB converters using the proposed VBS retain most of the characteristics of the conventional dual output DAB converters and achieve voltage balancing effectively. A 3-kW prototype converter was built and tested to verify the performances of the proposed VBS.