Study On Quench Propagation Properties Of High Temperature Superconductor

Compared with the low temperature superconductor in the liquid helium temperature region(4.2K),the high temperature superconductor still has high current-carrying capacity and thermal stability in the liquid nitrogen temperature region(77K),which is widely concerned by domestic and foreign electric power researchers.High temperature superconducting(HTS)magnet is prone to suffer from various disturbances during operation,which not only threatens the safe operation of the magnet,but also affects the operation of the whole power system.The stability and quench of superconductors has been the focus of the research and exploration of superconducting applications.The research on the quench propagation characteristics of superconductors has important guiding significance for improving the thermal stability of superconductors and the design of reasonable and reliable quench protection system.It is necessary to study the quench propagation properties of high temperature superconductor.This paper studies quench propagation characteristics of the first generation and the second generation high temperature superconducting tape,and double parallel HTS tapes and small HTS coil.By simulating the quench of high temperature superconductor,we further understand the thermal diffusion process of high temperature superconductor.The paper has completed the following works:(1)Established the experimental platform of high temperature superconductor.Studied the influence of reinforcement materials and base materials of HTS tape on the quench propagation characteristics experimentally.Analyzed the special phenomenon of superconducting tape during quench.Compared the quench propagation characteristics of 1G HTS tape and 2G HTS tape.(2)Studied the quench propagation characteristics of superconducting coil,parallel parallel tapes and parallel stacking tapes by experiments,and anlysised the quench propagation characteristics of high temperature superconductor in each direction.(3)Established the quench propagation model of HTS tape based on the COMSOL Multiphysics software.Anlysied the quench propagation characteristics of parallel HTS tapes and the small superconducting coils model.Analyzed the change of thermal characteristics during the quench process of high temperature superconductor.Verified that the propagation velocity of the superconductor is anisotropic.Compared the experimental results.Analyzed the difference between the two measurements.