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针对超临界二氧化碳部分预冷循环,建立了循环热力学模型和经济学模型,分析了循环关键参数对循环效率和系统成本的影响.将透平进口温度、循环压比和换热器窄点温差作为优化变量,以系统的效率最大和成本最小为优化目标,利用非支配排序遗传算法(NSGA-Ⅱ)进行多目标优化,获得优化解集的Pareto曲线.结果表明:超临界二氧化碳部分预冷循环是一种高效率的热力循环;在给定条件下,减小窄点温差、提高热源温度、提高透平和压气机的等熵效率可以增加系统效率,增大循环压比、降低热源温度、增加窄点温差可以降低系统成本;优化所得到的系统效率和成本呈同时增加的关系,需要从工程实际情况考虑来选取最优方案.“,”In this paper the thermodynamic and economic models for the supercritical CO2 (SCO2) partial pre-cooling cycle are established,and the influence of key parameters on the exergy efficiency and system cost of the cycle is analyzed.The non-dominated sorting genetic algorithm Ⅱ (NSGA-Ⅱ) is used to optimize the thermodynamic parameters of the SCO2 cycle with exergy efficiency and net power output as its objective functions,and Pareto optimal curves are obtained.The results show that the SCO2 partial pre-cooling cycle is highly efficient.Under the given conditions,the cycle exergy efficiency could be increased by decreasing the pinch temperature of condensers,or increasing the efficiency of turbine and compressors.Moreover,the system cost could be reduced by improving the pressure ratio,reducing the heat source temperature or increasing the pinch temperature.And the Pareto curve indicates that the exergy efficiency and system cost cannot reach the optimal state at the same time,so the optimal solution should be selected according to the actual conditions.