双根堆叠YBCO超导带材缺陷状态下失超传播规律研究

因双根并绕堆叠结构的YBCO带材能够进一步增加设备承载电流密度，被广泛应用于大型超导设备线圈绕制中.本文研究了外层有包绕绝缘的双根并绕堆叠YBCO带材有缺陷情况下的失超传播特性，应用有限元法方法，建立了双根YBCO带材堆叠状态下失超仿真模型，研究了存在不同缺陷的情况下双根堆叠超导带材的失超传播特性，探索了堆叠带材在不同工作电流下传播速度(NZPV)等参数的变化趋势，同时探究了不同铜稳定层厚度下并绕堆叠带材失超传播规律.结果表明缺陷区域面积增加以及铜稳定层厚度减小，都将导致双根并绕堆叠结构的二代高温超导带材失超传播速度增加，在带材上的温升增加，增加失超的风险.研究结果可以为超导设备安全稳定运行参数设置提供支持.

Study on the Quench Characteristics of Double Stacked YBCO Tape under Defects

Double stacked YBCO tapes are widely used in coil winding of large superconducting devices because of their ability to further increase the current density of the device. In this paper, the finite element analysis method is applied the to investigate the quench characteristics of double stacked YBCO tapes with defective outer insulation, and the quench characteristics of double stacked YBCO tapes with different defects are studied. The trend of the normal zone propagation velocity (NZPV) at different operating currents was investigated, and the quench propagation of the stacked tapes with different copper stabilization layer thicknesses was also investigated. The results show that the increase of the defect area and the decrease of the thickness of the copper stabilization layer will lead to the increase of the NZPV of the second generation high temperature superconducting tapes with double stacking structure and the increase of the temperature rise on the structure, which will increase the risk of quench. The results of the study can support the setting of parameters for safe and stable operation of superconducting devices.