FUEL CELL SYSTEM

• Main Authors: SUGAWARA TATSUYA, KACHI ISATO, KANAZAWA TAKUMA, SUZUKI MIKIHIRO, WAKABAYASHI TAKUYA, KOBAYASHI TOMOKI
• Format: Patent
• Language: English
• Published: 08.11.2012
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

PROBLEM TO BE SOLVED: To provide a fuel cell system which can achieve both humidification by off-gas in a humidifier and energy recovery from off-gas by an expander with high efficiency.SOLUTION: The fuel cell system comprises an expander 42, driven by off-gas discharged from an oxidant discharge passage 12, which conveys motive power to a compressor 40; a bypass passage 20 which bypasses a humidifier 30 in the oxidant discharge passage 12; a flow rate adjustment valve 21 which changes the opening of the bypass passage 20; a voltage sensor 15 which detects the output voltage of a fuel cell 10; a current sensor 16 which detects the output current of the fuel cell 10; and a bypass control unit 61 which, according to the output power of the fuel cell 10, changes, with the flow rate adjustment valve 21, a bypass ratio or a proportion in magnitude of an off-gas flow circulating in the bypass passage to the total amount of off-gas discharged from the fuel cell 10 to the oxidant discharge passage 12.