The recompression carbon dioxide Brayton cycle has the advantages of simple structure and high cycle efficiency. However

the recompression cycle faces the problems of large boiler pressure drop

high cooling wall temperature and difficult waste heat utilization when applied to coal-fired power plants. The partial cooling carbon dioxide cycle can effectively alleviate the above problems when integrated with coal-fired boilers by virtue of its own circulation characteristics. A thermal calculation program for a 600 MW coal-fired power generation system with partial cooling carbon dioxide cycle is written using MATLAB. Firstly

the effect of single parameter variation on the thermodynamic performance of the system is investigated. The results show that the system efficiency is highest when the main compressor inlet pressure and temperature are near the critical point; the system efficiency drops suddenly when the pre-compressor works near the critical point; the system efficiency is highest when the split ratio and reheat pressure are 0.35 and 17 MPa

respectively. The particle swarm optimization is applied to the partial cooling cycle

and the results show that the partial cooling cycle can achieve the efficiency close to that of the recompression cycle under the suitable design parameters. Compared with the recompression cycle

the mass flow rate of the partial cooling cycle decreased by 17.46% and the boiler inlet temperature decreased from 462.45 ℃to 429.39 ℃.