Influence of operating parameters on the thermal efficiency of complex combined cycle

Abstract

This study deals with a thermodynamic analysis of a combined cycle of 400, MW provided with a system of steam injection in the combustion chamber, two steam extractions from the steam turbine, two open feedwater heaters, and a system of air combustion cooling. This study describes the influence of external and internal parameters on the cycle performance. The power plant is constituted by a Gas Turbine cycle with steam injection and compressed air cooling usystems, a Eteam Turbine cycle with two extractions and a Heat Recovery Steam Generator. A numerical simulation of the combined cycle with Engineering Equation Solver software is realized by considering operational range of variables such as compression ratio, air excess, steam injection rate, steam extraction pressure, condensation pressure, and other parameters. In this chapter, influences on the overall cycle performance are analyzed. The goal of this study is to describe the change on the cycle performance and efficiency with ambient temperature influence and with pressure extraction.