| 摘要 |
PURPOSE:To detect deterioration of a fuel cell by mounting a.c. impedance measuring equipment in a fuel cell stack, measuring a.c. impedance during operation, and comparing measured a.c. impedance with normal a.c. impedance. CONSTITUTION:a.c. impedance of each of fuel cell stacks 60-1-60-n is measured with a.c. impedance measuring equipment 61-1-61-n by applying high-frequency voltage across positive and negative terminals of each fuel cell stack. Since load current of fuel cell is d.c. current, a.c. current applied to the fuel cell is not influenced by the load current of the fuel cell. Therefore, even when the fuel cell is operated, a.c. impedance can be measured. Since, a.c. impedance of a fuel cell stack including deteriorated cell shows different value from that of normal cell stack, by comparing both values, normality of cell stack 60-1-60-n can be determined. |
