Abstract: The ohmic power supply of HL-2A tokamak and its operation mode without circulating current are described and the converter status detector is also introduced, which can be used to monitor the status of all thyristors and then to judge the zero-crossing of load current. The disadvantages such as low precision and low reliability of current measurement have been overcome and the response time of this detector reaches 1ms. The volt-second of ohmic transformer (5Vs) is fully used and the plasma current is up to 420kA because of the operation mode without circulating current.

Key words: HL-2A tokamak, Ohmic power supply, Circulating current, Converter status detector

摘要： 介绍了HL-2A欧姆电源及其逻辑无环流运行方式。用于判断负载电流过零点的变流器状态检测器通过监测变流器每个晶闸管桥臂的状态来判断负载电流是否为零，克服了直接测量负载电流精度低、可靠性差的不足。此检测器的响应时间可达1ms。欧姆电源运行在逻辑无环流方式下可使欧姆变压器的伏秒数得到充分利用，提高装置的放电参数，等离子体电流可达420kA。

关键词: HL-2A 装置, 欧姆电源, 环流, 变流器状态检测器