A Novel Method to Eliminate the Screening Current-Induced Magnetic Field in a Non-insulated REBCO Double Pancake Coil

The screening current-induced magnetic field (SCIF) brings bad effects on the field quality of REBCO high-temperature superconducting (HTS) magnet, which is mainly due to its specific large aspect ratio structure. In this paper, numerical simulation and experiments were conducted to investigate SCIF in a non-insulated HTS DP coil firstly. Then, a heating flux method was proposed to help eliminate the effect of screening current in a GdBCO HTS double pancake (DP) coil. A heating plate was mounted under the DP coil and used to generate a heating flux, which could increase the temperature and decrease critical current of the HTS coil in a short time. The decreasing of critical current could reduce the margin left for the screening current and eliminate the effect of SCIF further more. Heating flux experiments were performed to verify its effects on eliminating SCIF in the DP coil at the end. The results show that the SCIF could be reduced obviously by the method of heating flux. The research provides an important reference to eliminate SCIF in the HTS magnet.