A Phase-shift Double Full-bridge (PSDB) Converter with Three Shared Leading-legs

This paper proposes a novel PSDB converter with three shared leading-legs. The ZVS of all the primary-side switches can be realized with wide conversion range (55%~100%) and full load range. Moreover, the effective duty cycle has nothing to do with the dead time. Thus, the PSDB would be useful for high switching frequency application. A 250W PSDB converter has been made with GaN transistors, SiC diodes, and planar transformers to verify the characteristics of PSDB. The experimental results show that the PSDB converter can achieve a peak efficiency of 90.6% when the switching frequency is 300kHz.