CONTROL DEVICE FOR FUEL BATTERY POWER GENERATION SYSTEM, POWER GENERATION SYSTEM AND CONTROL METHOD FOR FUEL BATTERY POWER GENERATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a control device, a power generation system, and a fuel battery control method capable of protecting a fuel electrode and an air electrode of a fuel battery while reducing the amount of gas to be supplied for stopping the operation of the fuel battery.SOLUTION: There is provided a control device for a fuel battery which has a fuel electrode supplied with fuel gas and an air electrode supplied with oxidant gas, and supplies exhaust fuel gas passed through the fuel electrode and a part of exhaust oxidant gas passed through the air electrode to a gas turbine. When it is determined that the fuel battery is to be stopped, the control device stops supply of the fuel gas and the oxidant gas after detecting that the gas turbine is stopped, maintains a state in which the pressure of the fuel electrode is higher than the pressure of the air electrode and the differential pressure therebetween is within a threshold differential pressure, reduces the pressure of the fuel electrode and the air electrode so that the pressure of the air electrode and the fuel electrode is not more than a threshold pressure, and then closes a flow path intercommunicating with the fuel electrode.SELECTED DRAWING: Figure 2