| 摘要 |
PURPOSE:To prevent a grounding fault in any place of a cell system by grounding the middle point of fuel cells connected in series with a grounding conductor having a switching device. CONSTITUTION:Fuel cells 1 connected in series are connected to a general power source line through an a.c. breaker 4, a DC/AC convertor 2 and others. A grounding conductor connected with a switching device 7 and a resistance 6 in series is connected to the middle point of the fuel cells. If a grounding fault arises, voltage applied to the resistance 6 or current i flowing through the resistance 6 is detected and the breaker 4 is opened and the switching device 7 is also opened. Even if the grounding fault arises in any place of a system such as the AC side A and the DC side B of the breaker 4, the fault is removed and the fuel cell is protected from the grounding fault. |
