Supercritical carbon dioxide(S-CO_2) cycle has great potential when applied to coal-fired power generation industry. By EBSILON Professional software

the model of a 1 000 MW coal-fired S-CO_2 power plant was established. On this basis

thermodynamic performances of the system

such as the energy flow and exergy characters

were analyzed. The influence of key parameters including the temperatures at the turbine inlet and the mass flow ratio of the compressor on thermodynamic performance of the system were also discussed. The results show that

under the given condition

the power generation efficiency and exergy efficiency of the S-CO_2 system can reach 47.32% and 46.11%

which are 1.21% and 1.17% higher than that of the typical Rankine cycle

respectively. Among all the exergy losses

the losses of the boiler contributes the largest

which is 74.55%

and the exergy efficiency of the boiler is 59.83%. When the input temperature of the turbine raises from 500 ℃ to 660 ℃

the power generation efficiency of the system increases by 7.98%

and the standard coal consumption rate decreases by 43.03 g/(k W·h). The increment of mass flow ratio of the compressor can lead to an increase in both the gross generation power and the power consumption of the compressors. Therefore

there exists an optimal mass flow ratio of the compressor. When the mass flow ratio of the compressor is 28%

the gross power generation efficiency reaches 47.65%

which is the highest.