FUEL CELL SYSTEM

• Main Author: MIYAKUBO HIROSHI
• Format: Patent
• Language: English
• Published: 06.12.2002
• Edition: 7
• 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 capable of detecting leakage of hydrogen during operation, with less detectors. SOLUTION: The hydrogen gas delivered from a tank 4 is measured for pressure and temperature with sensors 14 and 15, and its flow rate is adjusted by a restriction area A of a valve 5, so that it is supplied toward a stack 1 at the sound speed. The waste hydrogen gas in the stack 1 is repeatedly supplied to the stack 1 by a recirculation device 6. When the leakage of the hydrogen gas is detected, the fluctuation in the load amount of a drive motor 23 is canceled with a secondary cell 24, so that the normal operation of the stack 1 is forced. Since the hydrogen gas passes through the valve 5 at the sound speed, the condition of hydrogen gas in the lower stream of the valve 5 is not required to be considered when calculating the mass flow rate of the supplied hydrogen gas. Whether hydrogen gas is leaking or not is known by comparing the calculated mass flow rate with the mass of the hydrogen gas actually consumed for power generation which is known from the current value of the stack 1.