Dead‐time effect analysis of a three‐phase dual‐active bridge DC/DC converter

The dead‐time effect is observed in the three‐phase dual‐active bridge (DAB) DC/DC converter. The occurrence of the dead‐time effect depends on the relationship of the switching frequency, the phase shift value, the dead‐time value and the equivalent conversion ratio. The dead‐time effect may have a significant impact on the converter performance when high switching frequency, wide input and output voltage range or wide operation power range are required. Therefore, comprehensive research of the dead‐time effect is essential to improve the design of the three‐phase DAB converter over a wide operation range. In this study, all the cases of the dead‐time effect in the three‐phase DAB converter are analysed in terms of the buck, boost, and matching states. The expressions of the transmission power, constraint conditions, and key time of the dead‐time effect are derived for each state. The operation waveforms of the dead‐time effect are also presented to better understand the dead‐time effect. Finally, the analysis is verified by both simulation and experimental results.