A fuel-cell/battery hybrid DC backup power system via a new high step-up three port converter.

In this paper, a fuel-cell (FC)/battery hybrid direct-current (DC) backup power system is proposed for high step-up applications. This system is composed of a newly developed non-isolated three-port converter, which achieves a high voltage gain by taking the advantage of a quasi Z-source network and an energy transfer capacitor. After analyzing the converter, a comprehensive comparison study and a design procedure are provided. Moreover, the controllers regulating the source power levels while smoothing the FC power profile according to the proposed energy management strategy (EMS) are designed based on the developed small-signal model of the proposed converter. Both hardware and controller design procedures are validated through the PSIM model of the whole system. As a result, it is shown that the proposed system can effectively couple FC and battery while transferring their energies to a high voltage DC bus according to the offered EMS. [Display omitted] • A FC/battery hybrid backup power system is proposed. • A new three-port high step-up converter is offered. • The converter includes quasi z-source network and an energy transfer capacitor. • An EMS is designed to smooth the FC load profile with the help of the battery. • The design example and system operation are verified by a non-ideal PSIM model. [ABSTRACT FROM AUTHOR]