A novel dual-phase-shift control strategy for dual-active-bridge DC-DC converter

There is power circulating flow in dual-active-bridge(DAB) dc-dc converter under the traditional single-phase-shift(SPS) control, and this is the main factor contributing to larger current stress and larger converter loss. In order to eliminate the power circulating flow and reduce the current stress, this paper proposes a novel dual-phase-shift(DPS)control method. By analyzing the operating principle of the DAB converter under the proposed DPS control method, the steady-state power model and small-signal equivalent mathematical model, as well as the constraint condition of eliminating the power circulating flow, are derived and established, on the basis of which the closed-loop controller is then designed. The simulation and experimental results verify the correctness and excellent performance of the proposed DPS control method.