Plasma and Fusion Research

Volume 14, 1405167 (2019)

Regular Articles

A Fast Discharge Scheme of Toroidal Field Coils for Fusion Demo Reactors
Yasuyuki ITOH1), Hiroyasu UTOH2,3), Yoshiteru SAKAMOTO2,3), Ryoji HIWATARI2,3) and Joint Special Design Team for Fusion DEMO3)
1)
Fukui University of Technology, Fukui 910-8505, Japan
2)
National Institutes for Quantum and Radiological Science and Technology, Rokkasho, Aomori 039-3212, Japan
3)
Joint Special Design Team for Fusion DEMO, Rokkasho, Aomori 039-3212, Japan
(Received 5 August 2019 / Accepted 12 November 2019 / Published 12 December 2019)

Abstract

This paper describes an emergency fast discharge scheme of toroidal field (TF) coils of fusion demo reactors for reduction of induced voltage applied to turn insulations of conductors. TF coils are divided into serially connected segments that are electrically isolated from each other and only the coil segment having a failed coil is rapidly discharged. It was found from a circuit current analysis that this discharge scheme enables to reduce the insulation voltage with a factor of ~0.6 or less and which would contribute to ensure reliability of the turn insulations.

Keywords

nuclear fusion, toroidal field coil, quench, first discharge, turn insulation voltage, fusion demo reactor

DOI: 10.1585/pfr.14.1405167

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References

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