Abstract: Based on the Agreement of Institute of Plasma Physics Chinese Academy of Sciences (ASIPP) and Ministry of Science and Technology of China during the Thirteen Five-Years Plan (so called 13∙5 plan), A dedicated test complex of superconducting magnet for China Fusion Engineering Test Reactor (CFETR) will be constructed in Hefei, China. A pair of high temperature superconducting (HTS) current leads rated at 100 kA for the CFETR magnet test complex is being designed at ASIPP. Because magnetic energy stored in the toroidal field magnet is 134 Giga Joules which are 3 times higher than the ITER case, HTS current leads must work in high voltage and nominal current without performance degradation during the magnet quench. In order to verify the safety and reliability of HTS current lead, this paper will numerically simulate the time of loss of flow accident (LOFA) from 50 K helium stoppage to the current sharing temperature starting and the burnout time from the current sharing temperature starting to the hotspot temperature of 200 K or the max. voltage of 100 mV along HTS module. The load line of static magnetic field is presented to predict the maximum current carrying capacity of HTS module. The inhomogeneous current distribution as a function of magnetic field with/without external applied field of 30 mT for the 90 HTS stacks is calculated by ANSYS iteration to estimate the current margin. The analysis results indicate the LOFA time is more than 500 s and the full current burnout time of 30 s is better than the requirement of the toroidal field magnet fast discharge time constant of 20 s, the HTS module heat load is less than 15W.
Index Terms—HTS, Current lead, Safety, CFETR
Acknowledgment: This work was supported by the Research of CFETR Integration Engineering Design Project (Grant No. 2017YFE0300500).