FEM Analysis of Effect of Magnetism of Substrate on AC Transport Current Loss of HTS Conductor With Ferromagnetic Substrate

It is reported that the AC transport current loss of coated conductors with ferromagnetic Ni-alloy substrates is larger than the loss calculated by the Norris equation. This means the significant influence of the ferromagnetism of the substrate on AC transport current loss. In this paper, the current distribution and AC loss of HTS coated conductor with ferromagnetic substrate are analysed using the finite element method taking account of the nonlinear E-J characteristics. Calculated results show that the AC transport current loss is increased because the current distribution changes in the superconducting layer due to the concentration of magnetic flux in the substrate. The effect of magnetism of substrate on the current distribution of superconducting layer is illustrated and the AC transport current loss characteristics of the HTS coated conductor with ferromagnetic substrate are examined.