Abstract:The 1 000 MW two reheat units of a power plant are taken as the prototype,and the system model of two kinds of overheat use mode of external steam cooler and MC system is established by using EBSILON software.By calculating and analyzing the parameters of the water supply temperature of the two reheat units and the reduction of the overheat at all levels of the regenerative steam,the variable working condition characteristics of the MC system are obtained.The calculation results show that the external steam cooler can reduce the coal consumption by 0.446 g/kWh,and the energy saving benefit of MC system is more obvious,which is 2.104 g/kWh.With the gradual decrease of the load of the unit,the coal consumption of the external steam cooler is gradually increased and 0.869 g/kWh is reached under the 40% turbine heat acceptance working condition,and the system is reduced to 0.924 g/kWh.The energy saving effect of MC system decreases under low load,but the effect of comprehensive energy saving is remarkable.