A new three-phase high-power soft-switched DC-DC converter based fuel cell power conditioning system with minimized DC capacitor

This paper proposes a new fuel cell power conditioning system based on the three-phase high-power soft-switched dc-dc converter with minimized dc capacitor. The traditional fuel cell system minimizes the dc capacitor by adopting the dc active filter which consists of the dc chopper with active switches. The unique contribution of this paper is to minimize the dc capacitor by using the proposed pulsation power decoupling control with no extra cost. Moreover, the dc-dc converter adopts three-phase interleaved structure based current-fed dual-active-bridge (CF-DAB) converter, resulting in much smaller input current ripple and passive component. The CF-DAB converter realizes zero-voltage-switching (ZVS) operation for all switching devices without auxiliary circuits, resulting in the high-efficiency operation. Simulation and experimental results were presented to validate the theoretical analysis and advanced performance.