Edge and top/bottom losses in non-inductive coated conductor coils with small separationbetween tapes

Abstract

In this paper we consider two different finite-element models for computing ac losses incoils composed of coated conductors: a 2D model based on solving Maxwell’s equations bymeans of edge elements and a 1D model based on solving the integral equations for thecurrent density in the tapes. The models are tested for a configuration of practical interest,a non-inductive solenoidal coil for fault current limiter applications. We focused ourattention on the conditions when differences between the two models are expected toemerge, for example when the tapes are closely packed or when the dependence of thecritical current density on the local magnetic field is taken into account. We present anddiscuss several cases, offering possible explanations for the observed differences of ac lossvalues.