Numerical analysis of magnetization loss in finite-length multifilamentary YBCO coated conductors

In typical YBCO coated conductors with a width of 10 mm, a large AC loss is generated in a perpendicular transverse magnetic field. One of the means of reducing the AC loss is to divide the YBCO film into narrow filaments. The AC loss characteristics of multifilamentary YBCO coated conductors having a finite length were studied by numerical electromagnetic analysis using FEM. We neglected the current component perpendicular to the wide face of conductor; thus, the problem to be solved was reduced to a two-dimensional one on a plane parallel to the wide face of the conductor. An equivalent nonlinear resistivity obtained from a power law E-J relation was used to represent the superconducting property of filaments. The magnetization losses were calculated from the temporal evolution of current distribution in YBCO coated conductors. The frequency dependence of the calculated magnetization loss was discussed based on the change in the current distribution in the conductor. The conductor specifications as well as the operating conditions were varied in order to study their influence on AC loss characteristics.