This paper presents the dc fault analysis and it impact on the design of the triple-active bridge (TAB) converter. The inductor rms current ratio is an important factor to be considered in the overall design of dual active bridge converter. In this work, DC terminal fault assumes zero voltage at the terminal. The analytical model based on generalized harmonic approximation (GHA) is developed to derive the fault current magnitudes. Different power-sharing operating modes of TAB converter are analyzed in detail for the study. It is shown that the port operating at lower power has a higher fault rms current ratio, which results in a lower inductance value for design. Simulations are carried out in PLECS to validate the analytical study.
