Effective resistance of the HTS floating coil of the mini-RT project

Author

Yanagi, Nagato ; Mito, Toshiyuki ; Hemmi, Tsutomu ; Seo, Kazutaka ; Morikawa, Junji ; Ogawa, Yuichi ; Iwakuma, Masataka

Author_Institution

Nat. Inst. for Fusion Sci., Japan

Volume

15

Issue

2

fYear

2005

fDate

6/1/2005 12:00:00 AM

Firstpage

1399

Lastpage

1402

Abstract

A magnetically levitated superconducting coil device, Mini-RT, has been constructed using high temperature superconductors for the purpose of examining a new magnetic confinement scheme of high-beta plasmas. The floating coil is wound with Bi-2223/Ag tapes, and it is operated in the temperature range of 20-40 K. The excitation tests of the coil were carried out and persistent current was sustained for magnetic levitation. The decay time constant of the persistent current was measured and the effective resistance of the coil cables was evaluated. The obtained resistance shows a considerable increase than that predicted by the n-value model. This might be caused by some electromagnetic effects such as the loss generation with long-lived shielding currents. This consideration was examined by measuring the magnetization of an HTS sample coil.

Keywords

bismuth compounds; calcium compounds; copper compounds; high-temperature superconductors; lead compounds; magnetic levitation; persistent currents; plasma confinement; silver; strontium compounds; superconducting cables; superconducting coils; superconducting tapes; (BiPb)₂Sr₂Ca₂Cu₃O₁₀; 20 to 40 K; HTS floating coil; Mini-RT Project; coil cables; decay time constant; effective resistance; electromagnetic effects; excitation tests; high temperature superconductors; high-beta plasmas; loss generation; magnetic confinement; magnetic levitation; n-value model; persistent current; shielding currents; superconducting coil; superconducting tapes; Electrical resistance measurement; Electromagnetic measurements; High temperature superconductors; Magnetic confinement; Magnetic devices; Magnetic levitation; Persistent currents; Plasma measurements; Plasma temperature; Superconducting coils; Bi-2223; Mini-RT; fusion; magnetic levitation; shielding current;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/TASC.2005.849104

Filename

1439904