Global Optimization Control of Minimum Backflow Power for Dual-active-bridge Converters Under Dual-phase-shift Control
Dual-active-bridge(DAB)DC-DC converters are commonly used for energy conversion.However,traditional single-phase-shift control causes the converter to generate significant backflow power when the input and output voltage do not match,especially under light load conditions.The existing optimization strategy for backflow power based on dual-phase-shift(DPS)control has yet to consider the backflow power in the full power range,and there is a lack of research on the minimum backflow power in all operating modes.Therefore,this article proposes an optimal control strategy for DPS that considers full power range and full operating mode.Firstly,the mechanism of backflow power generation was elaborated in detail,and mathematical models for transmission and backflow power under different operating modes were established.Then,considering the power limits of different operating modes,the transmission power controlled by DPS is divided into different power zones.On this basis,a DPS optimal control strategy based on minimum backflow power is proposed,which obtains the optimal phase shift angle for each power region by analyzing the optimization trajectories under different operating modes,thereby improving the efficiency of the converter.Finally,an experimental platform was established to verify the feasibility of the proposed minimum backflow power control strategy.
dual-active-bridge converterdual-phase-shift controlminimum backflow powerwhole load rangefull working mode