Fuel cell power plant having a fuel concentration sensor cell

摘要

A fuel cell power plant ( 10 ) having a fuel concentration sensor cell ( 54 ) is disclosed for detecting a concentration of fuel in a fuel cell ( 12 ) of the plant ( 10 ). A portion of a fuel exhaust stream is directed to flow through the sensor cell ( 54 ) adjacent to a membrane electrode assembly ( 60 ) of the sensor cell ( 54 ). A power circuit ( 62 ) may or may not deliver an electrical current to the cell ( 12 ), while changes in voltage across the cell ( 12 ) that are proportional to changes in hydrogen concentrations within the fuel exhaust stream are detected by a detector ( 68 ) which communicates the changes to a controller ( 108 ) for controlling a rate of fuel supply to the fuel cell ( 12 ). A porous sensor water transport plate ( 74 ) cools, humidifies delivers and removes liquid from the sensor cell ( 12 ).