AC Loss Scaling of a REBCO Double-Pancake Coil Over Wide Temperature and Magnetic Field Regimes

AC loss is a critical consideration in the design of high temperature superconducting (HTS) magnets. REBCO coils exhibit excellent current-carrying capabilities and are popular choices for applications such as fusion magnets and superconducting magnetic energy storage. However, there is currently a lack of research on the AC loss of REBCO coils under low temperature and high field conditions. A quantitative understanding of AC loss over wide temperature and magnetic field ranges is urgently needed. This paper investigates the dynamic resistance, magnetization loss, and total loss of a small double-pancake coil (DPC) based on a 2D axisymmetric H formulation, at temperatures of 25 K, 50 K, and 77 K in perpendicular AC magnetic fields up to 5 T. The results show that at different temperatures, the dynamic resistance, total loss, and loss components of the DPC can all be scaled by its critical current, Ic, coil. This implies that results from the high-temperature, low field regime can be used to predict the loss values in the low temperature, high-field regime. In addition, these scaling behaviors are quantitatively explained by the extended equations. This study is expected to provide a valuable reference for the estimation of losses in high-field magnets.