Efficiency Optimization Strategy of Three Port Triple Active Bridge DC-DC Converter

Multiport dc-dc converter has attracted increasing research interest in ac/dc hybrid grid and vehicle systems due to the advantages of flexibility, low-cost and high-efficiency. However, under the conventional phase-shifting control strategy, mismatching of dc-port voltages may increase the current in transformer and switching devices, which reduce efficiency of multiport dc-dc converter. To solve the problem, a phase-shifting PWM strategy to control the power flow and minimize the losses of the isolated three port triple active bridge(TAB) dc-dc converter is proposed in this paper, in which phase-shifting control is used for managing the power flow between triple ports, duty cycle control is utilized for optimizing the system losses and ZVS conditions are checked. Finally, the simulation is conducted to validate the feasibility of the strategy.