| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a fuel cell system operable under a broad range of operating conditions while having high fuel utilization efficiency. <P>SOLUTION: A newly supplied hydrogen line 6 supplies a newly supplied hydrogen gas from a high pressure gas tank 2 the pressure of which is adjusted by a pressure adjusting valve 3 to an ejector 4. The ejector 4 mixes a surplus hydrogen gas exhausted from a fuel cell stack 1 with the newly supplied hydrogen gas to supply the mixed hydrogen gas to the fuel cell stack 1. A hydrogen gas line 8 for ejector circulation leads the surplus hydrogen gas exhausted from a fuel electrode outlet to the suction opening of the ejector 4. A hydrogen line 9 for pump circulation leads the surplus hydrogen gas exhausted from the fuel electrode outlet to the downstream of an ejector exhaust port, and a gas circulation pump 5 capable of forcibly circulating a gas is disposed in the middle of the line. A controller 15 determines a water blocking state based on the detected value of a cell voltage sensor 14, and the gas circulation pump 5 is intermittently operated until the blocking state is canceled. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
