Patent ID: 6955860

Claim:
A fuel cell power plant performing power generation using a hydrogen-containing reformate gas, comprising: a reformer comprising a reforming catalyst which generates the hydrogen-containing reformate gas from a source material in a predetermined activation temperature range; a start-up combustor which combusts a gaseous mixture of fuel and air and supplies a resultant combustion gas to the reformer to warm up the reformer to the activation temperature range; an air supply device which supplies air to the start-up combustor; a fuel supply device which supplies fuel to the start-up combustor; a sensor which detects completion of warming up of the reformer; and a programmable controller programmed to: control a fuel supply amount of the fuel supply device and an air supply amount of the air supply device to maintain an air-fuel ratio of the gaseous mixture at a specific rich air-fuel ratio with respect to a stoichiometric air-fuel ratio; and control the fuel supply amount of the fuel supply device and the air supply amount of the air supply device to cause a difference of the stoichiometric air-fuel ratio and the air-fuel ratio of the gaseous mixture to be greater than a difference of the specific rich air-fuel ratio and the stoichiometric air-fuel ratio, in the period after completion of warming up of the reformer until a combustion of the gaseous mixture terminates, by stopping air supply of the air supply device after completion of warming up of the reformer, and by stopping fuel supply of the fuel supply device at a timing later than a timing where the air supply device stops air supply to the start-up combustor.