| 摘要 |
2048674 9110267 PCTABS00006 A fuel cell (10) system in which a nitrogen (N2) gas is used on the anode section (11) and a nitrogen/oxygen (N2/O2) gaseous mix is used on the cathode section (12) to maintain the cathode at an acceptable voltage potential during adverse conditions occurring particularly during off-power conditions, for example, during power plant shutdown, start-up and hot holds. During power plant shutdown, the cathode section is purged with a gaseous mixture of, for example, one-half percent (0.5 %) oxygen (O2) and ninety-nine and a half percent (99.5 %) nitrogen (N2) supplied from an ejector (21) bleeding in air (24/28) into a high pressure stream (27) of nitrogen (N2) as the primary or majority gas. The ejector meters high pressure nitrogen gas with a choked orifice or venturi and uses the energy in the gas from the orifice or venturi to suck ambient air into the nitrogen stream before entering the cathode section. |
