Steady-state Characterization of Dual Active Bridge Converter Considering Transformer Excitation Characteristics

In recent years, solid-state transformers have been applied to the architecture of a variety of systems. Under the demands of different application scenarios, solid-state transformers can realize AC/DC conversion at different voltage levels, and the core function of the realization link is the DAB converter. However, in a large number of current studies on DAB converters, high-frequency transformers only work in the linear region, ignoring their nonlinear characteristics, and there is a large amount of margin. Therefore, this paper combines the nonlinear characteristics of high-frequency transformers and analyzes the steady-state operation of the DAB converter. Simulation results show that compared with the conventional operation mode, the maximum inductor current of the DAB converter increases from 6.74 A to 7.87 A when the high frequency transformer operates in the saturation region, an increase of about $16.7 \%$, which is similar to the theoretical analysis results, and it is promising to further explore the potential of the DAB converter.