Power generation system, and methods for starting and operating fuel cell in power generation system

Abstract

The present invention enables a fuel cell to be stably started by minimizing a lack of air in a gas turbine when starting the fuel cell. This fuel cell system comprises: a gas turbine () having a compressor () and a combustor (); a first compressed air supply line () that supplies compressed air (A), which has been compressed by the compressor, to the combustor; a solid oxide fuel cell (SOFC) () having an air electrode and a fuel electrode; a second compressed air supply line () that supplies partially compressed air (A), which has been compressed by the compressor, to the air electrode; a blower () that is disposed on the second compressed air supply line, and raises the pressure of the compressed air (A); a circulation booster line () connecting the upstream side and downstream side of the blower in the second compressed air supply line; a control valve () disposed on the circulation booster line; a control valve () disposed between the circulation booster line in the second compressed air supply line and the SOFC; and a control device () that closes the control valves and opens the control valves to start the blower when starting the SOFC.