Numerical Simulation and Experiment of AC Loss in Quasi-Isotropic Superconducting Strand

With the development of REBCO coated conductor (CC), the high temperature superconducting (HTS) strand with high current capacity and quasi-isotropic performance is expected to have a wide application. However, the alternating current (AC) loss is one of the major obstacles. This paper aims to study the AC loss of the quasi-isotropic strand stacked by the second generation (2G) HTS tapes and copper tapes at 77 K. In order to fully understand AC loss characteristics of the stacked-tape conductor, an efficient 3D finite element method (FEM) model based on T–A formulation was adopted in this simulation. The transport AC loss was measured by four-probe method using SR-830 lock-in amplifier at liquid nitrogen (LN2) bath. Moreover, the amplitude and frequency of transport current were also varied in this experiment. The simulation results are consistent with the experiment which is helpful for studying the AC loss of the quasi-isotropic strand.