Design study on a 100-kA/20-K HTS cable for fusion magnets

Seungyong Hahn, Jungbin Song, Youngjae Kim, Ki Jin Han, Haigun Lee, Yukikazu Iwasa, Yong Chu

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

Due to the > 100 times higher thermal stability of high temperature superconductor (HTS) than that of low temperature superconductor (LTS) and the capability of HTS to be operated at a liquid-helium-free temperature, an HTS cable is being considered a possible alternative to LTS for fusion magnets such as Toroidal Field (TF) coils in Tokamaks, and Helical coils in Stellarators. This paper presents a first-cut design of a 100-kA/20-K HTS cable, which could be an option for fusion magnets. Thermal behaviors of the cable were analyzed and compared quantitatively with those of a 100-kA/4.2-K Nb3Sn cable using the CryoSoft code THEA. In the paper, we demonstrated that the conventional concepts of the 'current sharing temperature (Tcs)' and the 'minimum quench energy (MQE)' may not be suitable for design and analysis of the HTS cable. Instead, 'thermal runaway temperature (TR)' and 'minimum runaway energy (MRE)' were proved to be more effective. Also, the post-quench temperature rise of the HTS cable, simulated by the THEA, was compared with that by the conventional analytic Z-function approach. The results demonstrate that the Z-function approach, proven to be effective for an LTS cable, may significantly overestimate the post-quench temperature rise of an HTS cable.

Original languageEnglish
Article number6957568
JournalIEEE Transactions on Applied Superconductivity
Volume25
Issue number3
DOIs
Publication statusPublished - 2015 Jun 1

Fingerprint

High temperature superconductors
high temperature superconductors
cables
Magnets
Cables
magnets
Fusion reactions
fusion
Superconducting materials
Temperature
temperature
field coils
Helium
stellarators
liquid helium
Thermodynamic stability
thermal stability
coils
energy
Liquids

Keywords

  • Fusion magnet
  • HTS cable
  • Minimum runaway energy
  • Thermal runaway temperature

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Condensed Matter Physics
  • Electronic, Optical and Magnetic Materials

Cite this

Design study on a 100-kA/20-K HTS cable for fusion magnets. / Hahn, Seungyong; Song, Jungbin; Kim, Youngjae; Han, Ki Jin; Lee, Haigun; Iwasa, Yukikazu; Chu, Yong.

In: IEEE Transactions on Applied Superconductivity, Vol. 25, No. 3, 6957568, 01.06.2015.

Research output: Contribution to journalArticle

Hahn, Seungyong ; Song, Jungbin ; Kim, Youngjae ; Han, Ki Jin ; Lee, Haigun ; Iwasa, Yukikazu ; Chu, Yong. / Design study on a 100-kA/20-K HTS cable for fusion magnets. In: IEEE Transactions on Applied Superconductivity. 2015 ; Vol. 25, No. 3.
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