Thermal Economy Analysis On The Thermodynamic System Of 600MW Supercritical Unit In Ningde Power Plant

This paper used equivalent enthalpy drop method and thermodynamic system state equation to calculate the thermo-economy indicators of the 600MW supercritical unit thermodynamic system in Ningde power plant. The thermo-economy indicators of 600MW supercritical unit and homebred 600MW subcritical unit were compared, the supercritical unit's thermo-economy was superior to the subcritical unit obviously, the causations mainly lay in the ideal circle thermal efficiency and the relative internal efficiency of turbine were improved through the increase of initial parameter. Simultaneously, the actual performance data and the design data were also compared; it showed that its heat consumption rate didn't achieve the design value. The reasons were the steam cylinders efficiency of turbine falling down and the shaft-packing leakage increasing. In addition, the operational parameters deviating design value, the input of reheater spray and the increment of small steam turbine's quantity also increased the heat consumption rate.