Influence of low electric field parts of electric field–current density curves of superconductors on their ac loss characteristics

Abstract

We performed numerical electromagnetic field analyses to investigate the influence of the low electric field parts of the electric field (E)-current density (J) curves of superconductors on their ac loss characteristics. A simple one-dimensional model across the width of a coated conductor was used for the analyses. Whereas we fixed the n value of the high E part of E-J curves of superconductors, we varied the n values of low E parts. J distributions as well as E distributions were calculated in coated conductors carrying ac currents and/or exposed to ac magnetic fields. We examined the influence of the n values at low E part of E-J curves on ac loss characteristics and discussed the electric field regions that are relevant to ac loss generation. We also discussed the applicability of the results to copper-plated multifilament coated conductors.