Full power range DAB unified ZVS control strategy based on low current RMS

Inductive current RMS and soft switching are important performance indexes of dual active bridge DC-DC converter (DAB). This paper proposes a new optimal control strategy for the soft switching range based on the optimization of the effective value of the inductor current. This control strategy restricts the inductor current during switch action, ensuring a significant extension of the soft switching range across the entire power range, reducing switch losses, and achieving the accurate effective value of current, thereby further enhancing the efficiency of the DAB converter. Meanwhile, a new modulation method is proposed to achieve thermal balance between bridge arms. Finally, a simulation model is built and verified using Matlab.