Some factors determining the effective resistance between strands in flat cables (or superconducting filaments in tapes)

S. Takács, Masataka Iwakuma, K. Funaki

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Two effects are considered which can influence the effective resistance between crossing strands on flat cables or filaments in twisted tapes. As analogous cases, the one-layer Rutherford-type cable with classical superconductors and the tapes with twisted BSCCO filaments in a silver matrix in perpendicular magnetic fields are considered as a model. At first, the amount of the central core between the strands and the silver matrix between the filaments increases the effective conductance compared with the direct current paths, which is supposed to be proportional to the touching area of filaments. The increase factor is about two and can be easily suppressed by other effects, such as the contact resistance between the superconductor and the matrix. However, due to the strong anisotropy of critical parameters for high temperature superconductors, this effect can partially compensate the influence of the usually weaker critical current density perpendicular to the tape. The second effect is connected with the existence of the induced voltage between any points of crossing filaments. This leads to an additional effective conductance, proportional to the square of the total number of the filaments. This contribution is prevailing for the anisotropic superconductors. Therefore, to obtain low ac coupling losses in BSCCO tapes, structures with smaller filament number are required. This case is analogous to round structures, leading to ac losses proportional to the square of the layer number in the field direction.

Original languageEnglish
Pages (from-to)405-411
Number of pages7
JournalSuperconductor Science and Technology
Volume13
Issue number4
DOIs
Publication statusPublished - Apr 1 2000

Fingerprint

Flat cables
strands
Tapes
cables
tapes
filaments
Superconducting materials
Silver
High temperature superconductors
Contact resistance
matrices
silver
Cables
Anisotropy
Magnetic fields
contact resistance
high temperature superconductors
Electric potential
critical current
direct current

All Science Journal Classification (ASJC) codes

  • Ceramics and Composites
  • Condensed Matter Physics
  • Metals and Alloys
  • Electrical and Electronic Engineering
  • Materials Chemistry

Cite this

Some factors determining the effective resistance between strands in flat cables (or superconducting filaments in tapes). / Takács, S.; Iwakuma, Masataka; Funaki, K.

In: Superconductor Science and Technology, Vol. 13, No. 4, 01.04.2000, p. 405-411.

Research output: Contribution to journalArticle

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