Study of 2G high temperature superconducting coils: Influence of anisotropic characteristics

This paper focuses on the study of anisotropic characteristic of second generation high-temperature superconductors (HTS), and how it influences the performance of HTS coils. The critical current of 4 sections of a HTS coil is measured and compared. The sectional difference of critical current exists due to an HTS anisotropy. A numerical method is introduced to consider the HTS anisotropy using finite element method. The model shows good consistency with experimental results. The model demonstrates that the anisotropy changes the current distribution inside the coil, and the discrepancy of critical current in different sections is the joint-effect of the anisotropy and shielding current. The paper discusses the possibility to optimize the performance of HTS coils by changing the anisotropic characteristic. Based on the study, strategies to improve the performance of HTS coils are provided.