在“人造太阳”EAST装置的内部，除了存在几千万度的高温等离子体外，还存在由低温系统提供的4.5 K(-268.65 ℃)低温超临界氦，将超导磁体冷却至临界温度以下，使其工作保持在超导态。EAST低温系统是目前中国最大的氦低温系统，其当量制冷量超过2 kW/4.5 K。首先介绍了EAST低温系统的工作原理与系统组成，然后描述了压缩机站、制冷机、分配系统和低温测量控制系统，最后简单阐述了EAST低温系统的运行情况。

Besides high temperature plasma heated to millions of degrees, there are 4.5 K supercritical helium provided by cryogenic system in the “artificial sun” EAST device to cool the superconducting magnets to below the critical temperature. At present, EAST cryogenic system is still the largest cryogenic helium system in China and its equivalent refrigerating capacity at 4.5 K is over 2 kW. This paper introduces the working principle and system composition of EAST cryogenic system, describes compressor station, refrigerator, distribution system and cryogenic measurement and control system. Finally, the operation of EAST cryogenic system is briefly described.