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超临界 CO2布雷顿循环(S-CO2)被认为是未来太阳能发电最具潜力的热循环形式，但较高的透平入口温度对蓄热提出了很高要求。该文提出了一种S-CO2循环与有机朗肯循环(ORC)结合的发电系统。白天利用S-CO2循环发电，并将排出的废热储存，夜间将储存的热量释放用于ORC部分发电，在实现系统昼夜连续发电的同时又避免了高温蓄热遇到的困难。仿真计算表明，在联合循环中硅油类工质循环性能较好，当 ORC 最高温度达到220~230℃时 ORC 发电量即可达到总发电量的50%，并且此时整体效率可保持在38%以上。研究结果表明，S-CO2与 ORC 联合循环有能力在保持较高系统整体效率的同时，即实现了昼夜连续发电又避免了高温蓄热。“,”ABSTRACT:Supercritical CO2 Brayton cycle (S-CO2) is known as the most potential type of the next generation of the solar power station. However, high turbine inlet temperature brings difficulties to thermal storage. This paper presented a S-CO2 and organic Rankine cycle (ORC) combined system. The system generates power by S-CO2 part during the day and by ORC part during the night. Power source of the ORC part is the heat releasing of the S-CO2 part during the day and which is stored. Thereby, this solar power system could generates power continuously day and night, at the same time, difficulties brought by high temperature to thermal storage can be avoided. Simulating calculation of this paper indicates that siloxanes show better performance than other fluids in this system, the ORC part power output reaches 50% of the whole system power output when the ORC turbine inlet temperature is about 220-230℃, and the thermal efficiency of this system can be kept above 38%. Researches show that the S-CO2 and ORC combined system has the ability to keep high system efficiency, generate power continuously day and night, and avoid thermal storage at high temperature at the same time.