Investigation of the Over Current Characteristics of HTS Tapes Considering the Application for HTS Power Devices

High temperature superconductor (HTS) is developed for applications in HTS power devices such as power transmission cable, transformers, superconducting fault current limiter (SFCL), motor, and generators. HTS power devices applied in power systems might undergo over current, such as over load, fault conditions, and unbalanced current. The electrical characteristic analyses of ${\rm Bi}_{2}{\rm Ca}_{2}{\rm Sr}_{2}{\rm Cu}_{3}{\rm Ox}$ (Bi-2223) HTS tapes and ${\rm YBa}_{2}{\rm Cu}_{3}{\rm Ox}$ (YBCO) tapes are very important for the application of HTS power devices. In this study, the transient phenomenon of HTS tapes was analyzed when the DC over current as well as the AC over current flow. Also, the experimental results of breakdown cycle, variation of temperature and resistance according to fault current in HTS tapes were analyzed. These results would be very significant data and give good information in order to design and fabricate HTS power devices.