The second-generation high-temperature superconductor REBCO is one of the most valuable candidates that meet the requirements of future magnetic confinement fusion device. Quench behavior of an improved high-current REBCO composite conductor is simulated by a 1-D finite element method. Indium-tin alloy foil placed in the gap between stabilizer, jacket, and superconducting tape stacks can significantly reduce thermal contact resistance, which leads to an increase on the minimum quench energy of composite conductor. Short perturbations have a better response to this improvement than long perturbations, due to the low normal zone propagation velocity (NZPV) of REBCO conductor. For short perturbation (perturbation length ($l_{p}$ = 0.1 m), the peak temperature in cable and helium drops 12.76 and 17.99%, respectively, after soldered. Due to the change of heat transfer in a composite conductor caused by helium wave propagation, the development and maximum length of normal zone significantly decrease from 13.06 to 4.78 m under long perturbation ($l_{p}$ = 10 m) circumstance. High current REBCO composite conductor with proper indium-tin alloy soldered can enhance the stability and safety of composite conductors under severe working conditions, but it also slows down the NZPV and hinders the quench detection of high-temperature superconducting magnet.

中文翻译：

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铟锡焊REBCO复合导体失超行为的热工水力分析

第二代高温超导体REBCO是满足未来磁约束聚变装置要求的最有价值的候选材料之一。通过一维有限元方法模拟了改进的大电流 REBCO 复合导体的淬火行为。将铟锡合金箔放置在稳定器、护套和超导带堆之间的间隙中，可以显着降低接触热阻，从而提高复合导体的最小失超能。由于 REBCO 导体的法向区传播速度 (NZPV) 较低，短扰动对这种改进的响应比长扰动更好。对于短扰动（扰动长度 ($l_{p}$ = 0.1 m)，焊接后电缆和氦气中的峰值温度分别下降 12.76% 和 17.99%。由于氦波传播引起复合导体内传热的变化，在长扰动（$l_{p}$ = 10 m）情况下，法向区的发展和最大长度从13.06 m显着减少到4.78 m。焊接适当的铟锡合金的大电流REBCO复合导体可以增强复合导体在恶劣工作条件下的稳定性和安全性，但也会减慢NZPV并阻碍高温超导磁体的失超检测。