Effect of the geometry of HTS on AC loss by using finite element method simulation with B-dependent E-J power law
Mono and multifilamentary HTS tapes exhibit non-negligible AC loss in self-field and considerably higher losses in the presence of external magnetic field. The effect of the conductor’s geometry on the AC loss has been investigated in this paper. The nonlinear electromagnetic properties of the superconducting material are expressed with a B-dependent E-J power law and are implemented in Finite Element Method commercial software. The critical current density and the power index n dependence on B are obtained from DC measurements of a real Bi-2223 tape. AC loss comparison between monofilamentary conductors of rectangular, elliptical, square and round geometry has been performed in self-field and applied external perpendicular magnetic field. The areas of the cross-section and the superconducting-core-to-Ag ratio have been kept constant in the simulations. To complement the AC loss analysis, the distribution of the current density and the magnetic field of the different geometries are presented.