COMPOSITE POWER GENERATION SYSTEM AND CONTROL METHOD FOR COMPOSITE POWER GENERATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a composite power generation system and a control method for the composite power generation system that are capable of simply and appropriately adjusting an S/C ratio of a mixed gas supplied to a fuel cell.SOLUTION: A composite power generation system 10 comprising an SOFC 12 and a gas turbine 16 that is operated using an exhaust fuel gas discharged from the SOFC 12 comprises: an exhaust fuel supply line 32 for supplying the exhaust fuel gas from the SOFC 12 to the gas turbine 16; a re-circulation line 33 that is provided so as to branch from the exhaust fuel supply line 32 and returns the exhaust fuel gas to the SOFC 12; a fuel supply line 24 for supplying a mixed gas including the exhaust fuel gas to the SOFC 12; and a spray 38 for spraying water into the fuel supply line 24 on the basis of an S/C ratio, which is a molar ratio of moisture vapor to one carbon atom in the mixed gas, and a ruled S/C ratio required depending on an operation situation of the SOFC 12.SELECTED DRAWING: Figure 1