Study on configuration of gas-supercritical carbon dioxide combined cycle under different gas turbine power

In order to obtain the optimal configuration scheme of gas-supercritical carbon dioxide (SCO2) combined cycle system under different gas turbine capacities, the main parameters of each gas-SCO2 cycle scheme were optimized to maximize the cycle efficiency of the gas-SCO2 cycle system, and the scheme with the highest cycle efficiency was selected. The gas cycle power is 10 MW, 100 MW, 300 MW and 600 MW respectively. SCO2 cycle adopts cascade cycle, which is configured with different cooler series, number of flue gas-SCO2 heat exchanger and number of shunt pipe respectively. Twelve SCO2 cycle comparison schemes are designed. The results show that with the increase of gas turbine power, the cycle efficiency of gas-fired SCO2 cycle system also increases. The highest cycle efficiency configuration scheme under different gas turbine capacities is three-stage SCO2 cycle with three-stage cooling, and the cycle efficiency is 0.508, 0.562, 0.591 and 0.622 respectively. From increasing device for gas-SCO2 combined cycle system, the influence of the cycle efficiency of gas-SCO2 circulation system with the cooler-SCO2 sets, flue gas heat exchanger sets and increase with the increase of the shunt pipe number, increase equipment to improve the cycle efficiency level is: increase the flue gas heat exchanger > SCO2 increasing bypass line > cooler.