摘要: This paper presents the optimization analysis and simulation of the main Claude cycle of the EAST cryogenic system. A simulation program of this cycle was developed on the basis of the characteristics of the components and verified with the experimental results. The built-in volume ratio of the No.7 compressor was tested with the purpose of finding the optimum internal pressure ratio to comply with the external pressure ratio so as to increase the isothermal efficiency and cycle efficiency. In addition, the UA (U, heat transfer coefficient; A, heat transfer area) values of the heat exchangers, efficiencies of turbines, mass flow fraction of the turbine stream were analyzed in order to improve the capacity or efficiency of the cycle. Finally, in view of the estimated heat loads of EAST in future, an upgraded operational cycle of 1500 W/4.5 K +1000 W/3.5 K +5 g/s is proposed according to the simulation.