Advanced Modulation Scheme of Dual Active Bridge for High Conversion Efficiency

摘要

Dual-active-bridge (DAB) DC-DC converter draws recent attention thanks to the feature of bidirectional power flow, high-frequency transformer isolation, and soft switching. However, the topology suffers from low conversion efficiency at light load condition due to loss of soft switching and significant weight of circulating power. This paper targets the drawback and proposes the technique of pulse density modulation to fit the DAB operation and improve overall efficiency.