Four-Port AC/DC-DC/AC Dual Active Bridge Based Converter

In this paper, a Four-Port AC/DC-DC/AC conversion system is proposed using two full-bridge converters and a high-frequency transformer following the principle of Dual Active Bridge Converter. Two full-bridge AC/DC single-phase converters are connected by coupling their boost inductance to create a high-frequency transformer of the resulting proposed converter. The isolated power transfer between converters is controlled by the duty cycles and the phase-shift applied to the primary and secondary of the split transformer. The boundaries of the switching modes and the power transferred through the high-frequency transformer were obtained analytically. The system feasibility was validated by simulations and by a 300 W prototype with 94.9% maximum efficiency.