TWO-POWER-SUPPLY LOAD DRIVING FUEL CELL SYSTEM

摘要

Provided is a two-power-supply load driving fuel cell system capable of improving the durability of the fuel cell and the power efficiency of the system. Even if the variation of a load terminal voltage occurs, the variation of the output terminal of an FC can be suppressed due to the high-speed operation of an FCVCU including an SiC-FET, enabling the durability of the FC to be ensured. In addition, since IGBTs are employed in a BATVCU having large average passing power, the power loss of a fuel cell system can be reduced. It is therefore possible to construct a system that takes advantage of the characteristics of the switching elements used in the FCVCU and the BATVCU.

主权项

1. A two-power-supply load driving fuel cell system in which a load is driven by a fuel cell and an electrical storage device, comprising:
a first power conversion device disposed at output terminals of the fuel cell; and a second power conversion device disposed at terminals of the electrical storage device; wherein: the first power conversion device is constituted by a switching element including a silicon carbide field effect transistor referred to as an SiC-FET; the second power conversion device is constituted by a switching element made up from an insulated gate bipolar transistor referred to as an IGBT; a maximum current value of the fuel cell is set to he higher than a maximum current value of the electrical storage device; and furthermore, in a predetermined driving mode, a voltage value of the fuel cell is set to be lower than a voltage value of the electrical storage device, and an average passing power value of the second power conversion device is set to be higher than an average passing power value of the first power conversion device.