HTS Joint Resistance for High-Field Magnets: Experiment and Temperature-Dependent Modeling

Benefiting from the high critical temperature and high critical current, the second-generation high-temperature superconducting (HTS) tape is widely used in various large-scale magnet applications. Due to the length limitation of producing superconducting tapes, the joints between superconducting tapes are inevitable for large-scale high-field magnets. The joule loss from the joint resistance under over-current conditions is even larger, which will cause a sharp temperature rise, and will also decay the critical current of the superconducting tape. In this paper, 3 configurations of HTS joints are adopted to model the joint resistance characteristics using new methods, whose joint resistance model is coupled with the real-time operating temperature. The results show that the proposed temperature-dependent HTS joint resistance model well matches the experiment and analytical solution. Therefore, both the experiment and novel modeling investigation can provide useful and accurate references for the superconducting joints in real devices, and the temperature-dependent HTS joint resistance model can play an important role in giving early warnings of the over-current for HTS tapes and high-field magnets.

Automated summary

Benefiting from high critical temperature and current, second-generation high-temperature superconducting tapes are widely used in large-scale magnet applications. This study proposes a temperature-dependent model for the joint resistance of these tapes, which matches well with experimental and analytical results. The model can provide accurate references for designing superconducting joints and early warnings for over-current conditions.