Deterioration Characteristics of 2G HTS Tapes with Respect to Electrical Breakdown for Designing a High-Voltage Superconducting Apparatus

摘要

Considering the deterioration characteristics of 2G hightemperature superconducting (HTS) tapes is necessary to design a mechanically and electrically robust superconducting coil. In this study, the deterioration characteristics of 2G HTS tapes such as the critical current (I (c)) and n value are determined according to the electrical breakdown applied. AC, DC, and lightning impulse (IMP) voltages are applied to 2G HTS tapes stabilized by various materials to verify their deterioration characteristics. It is found that the degree of deterioration is dependent on the applied voltage and the type of 2G HTS tape. This implies that the deterioration characteristics of the 2G HTS tape by the discharge is influenced by the total energy of the input voltages whereas the variation in deterioration according to the type of the 2G HTS tape is a result of the electrical resistivity and hardness of the stabilizer material. Deterioration characteristics of 2G HTS tapes damaged by discharge voltages are analyzed by using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX).