High Efficiency Dual-Active-Bridge Converter with Improved Minimum Backflow Power Modulation Strategy

Dual-active-bridge converter using the single-phase-shift control makes the converter generate large backflow power when the input voltage and output voltage are not matched, especially under light loads condition. For this reason, this paper proposes a DPS-based minimum backflow power modulation strategy with full operating mode and full power range. Considering the power limitations of different operating modes, the transmission power controlled by DPS is divided into four different load ranges. On this basis, the optimal phase shift angle at optimal backflow power is obtained by determining the optimization path in various cases using the Karush-Kuhn-Tucker (KKT) function, which enhances the system efficiency. Finally, a platform is built to verify the feasibility of the proposed minimum backflow power strategy.