Electromagnetic field analyses of two-layer power transmission cables consisting of coatedconductors with magnetic and non-magnetic substrates and AC losses in theirsuperconductor layers

Abstract

Two-dimensional electromagnetic field analyses were undertaken using two representativecross sections of two-layer cables consisting of coated conductors with magnetic andnon-magnetic substrates. The following two arrangements were used for the coatedconductors between the inner and outer layers: (1) tape-on-tape and (2) alternate. Thecalculated magnetic flux profile around each coated conductor was visualized. In the caseof the non-magnetic substrate, the magnetic field to which coated conductorsin the outer layer are exposed contains more perpendicular component to theconductor wide face (perpendicular field component) when compared to that inthe inner layer. On the other hand, for the tape-on-tape arrangement of coatedconductors with a magnetic substrate, the reverse is true. In the case of the alternatearrangement of the coated conductor with a magnetic substrate, the magneticfield to which the coated conductors in the inner and outer layers are exposedexperiences a small perpendicular field component. When using a non-magneticsubstrate, the AC loss in the superconductor layer of the coated conductors in thetwo-layer cables is dominated by that in the outer layer, whereas the reverseis true in the case of a magnetic substrate. When comparing the AC losses insuperconductor layers of coated conductors with non-magnetic and magnetic substrates intwo-layer cables, the latter is larger than the former, but the influence of themagnetism of substrates on AC losses in superconductor layers is not remarkable.