Field and current distributions and ac losses in a bifilar stack of superconducting strips

TitleField and current distributions and ac losses in a bifilar stack of superconducting strips
Publication TypeJournal Article
Year of Publication2008
AuthorsClem JR
Journal TitlePhysical Review B
Volume77
Pages134506
Date PublishedApr
Type of ArticleArticle
ISBN Number1098-0121
Accession NumberISI:000255457200110
KeywordsARRAYS, CONDUCTOR, CRITICAL-STATE, FAULT CURRENT LIMITERS, II-SUPERCONDUCTOR, PERPENDICULAR MAGNETIC-FIELD, TRANSPORT CURRENTS, YBCO-COATED
Abstract

In this paper, I first analytically calculate the magnetic-field and sheet-current distributions generated in an infinite stack of thin superconducting strips of thickness d, width 2a >> d, and arbitrary separation D when adjacent strips carry net current of magnitude I in opposite directions. Each strip is assumed to have uniform critical current density J(c), critical sheet-current density K-c=J(c)d, and critical current I-c=2aK(c), and the distribution of the current density within each strip is assumed to obey critical-state theory. I then derive expressions for the ac losses due to magnetic-flux penetration both from the strip edges and from the top and bottom of each strip and I express the results in terms of integrals involving the perpendicular and parallel components of the magnetic field. After numerically evaluating the ac losses for typical dimensions, I present analytic expressions from which the losses can be estimated.

DOI10.1103/PhysRevB.77.134506
Alternate JournalPhys. Rev. B