Modeling of single-HB PWM modulated dual active bridge DC-DC converter with multifrequency average approach

This paper focuses on the modeling of Dual Active Bridge (DAB) DC-DC converter. Single-HB modulation has been studied in many papers, but no modeling work about this has been done. A multifrequency average model of DAB with single-HB PWM modulation is proposed in this paper. The proposed average model uses the dc, first and third coefficients in the Fourier series of transformer current as the state variables to improve model accuracy. Then, the modeling result is verified by simulation and the modeling accuracy reaches one-third of the switching frequency. It also indicates that the model will be more accurate if more terms in the Fourier series of variables are considered.