ITER直流隔离开关短路试验研究

基于ITER极向场变流器系统,分析了直流隔离开关短路故障，提出ITER直流隔离开关短路试验要求。基于中国科学院等离子体物理研究所直流测试平台，为ITER直流隔离开关短路试验设计了先建立直流电压再闭合短路开关的后短路试验方案，包括选取变压器档位、计算试验电流所对应的直流电压等内容。通过仿真和试验验证了试验方案的可行性，试验结果证明了直流隔离开关对短路故障的抑制能力满足ITER极向场变流器运行要求。经分析计算，350 kA试验电流需要直流电压270 V。在试验中，预设直流电压270 V时，试验电流达不到350 kA，将预设直流电压提高到300 V后，试验电流峰值达到362.5 kA，且超过350 kA的部分达到100 ms。实际预设直流电压比理论计算值大30 V，这是电网电压的波动造成的。

Research on short circuit test of ITER DC line disconnector

In this paper, firstly, the fault current of DC line disconnector is analyzed based on international thermonuclear experimental reactor (ITER) poloidal field(PF) converter system to propose the short-circuit test requirement of ITER DC line disconnector. Then, the short-circuit test scheme is designed based on the DC test platform in Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), including the selection of transformer tap position, the calculation of the DC voltage corresponding to the test current and so on. Finally, the feasibility of the test scheme is verified by simulation and experiment, and it is proved by the test results that the fault suppression ability of DC line disconnector meets the requirement of ITER converter operation. By analysis and calculation, 350 kA test current needs the DC voltage 270 V. In the test, if the DC voltage is preset to 270 V, the test current is less than 350 kA. After the DC voltage is preset to 300 V, the peak of test current can reach 362.5 kA and the duration of more than 350 kA can be up to 100 ms. The difference between the actual preset DC voltage and its theoretically calculated value is 30 V, which is caused by the voltage fluctuation of the power grid.