Numerical Study of the Electromagnetic-Thermal Characteristics During the Charging Process of Ultra-high Field HTS Insert Magnet

The rapid development of the rare earth barium copper oxide (REBCO) coated conductor makes it possible to manufacture ultra-high field (UHF) superconducting magnets. However, the thermal field inside REBCO high-temperature superconducting (HTS) insert during the charging process is not well understood because the temperature measurement inside magnet is complicated and generally not feasible. In this paper, the H-A formulation with a homogeneous strategy is employed to establish the simulation model. The designed 30-T magnet is computed to understand the distribution and variation of the thermal field inside HTS insert. The results demonstrate that the H-A formulation rapidly computes the temperature of large-scale magnets, and carry out complex thermal field and magnetic field analysis when considering the screening current. When the thermal field is under consideration, the electromagnetic characteristics change significantly compared to the computation without thermal field and the results are more accurate. Furthermore, the influence of the thermal field is distinct at different charging rates. This suggests that the thermal field should be taken into account especially at high charging rates to obtain a more realistic result.