LAUSR

Abstract Unlike superconductors on nonmagnetic substrates (SC/NM tapes) in a parallel magnetic field, the ferromagnetic substrates can cause obvious change of current density and magnetic field distributions in superconductor coated conductor (CC) tapes. In this case AC losses of CC tapes exposed to a parallel magnetic field cannot be neglected. In this paper, we investigate the electromagnetic response and AC losses of CC tapes using H-formulation model. The ferromagnetic loss of the substrate in a CC tape and the effect of magnetic field dependent permeability on AC loss are also considered. It can be found that the AC loss of a CC tape is much larger than that of a SC/NM tape, especially in weak applied magnetic fields. It is an effective way to significantly reduce AC loss of a CC tape by appropriately increasing the width of the ferromagnetic substrate. We also consider the CC tape carrying DC transport current and simultaneously exposed to a parallel AC magnetic field. The influence of the DC transport current on the AC loss is investigated. Moreover, AC losses of CC tape-array systems mainly depend on the arrangement and the vertical interval between CC tapes. We demonstrate that AC loss can be reduced effectively by decreasing the vertical interval between CC tapes.