July 2011

Conference Paper

Scattering-matrix arc detection on the JET ITER-like ICRH antenna

By:
Becoulet, A.; Vrancken, M.; Dumortier, P.; Durodie, F.; Evrard, M.; Huygen, S.; Lerche, E.; Van Eester, D.; Vervier, M.; Argouarch, A.; Blackman, T.; Graham, M.; Jacquet, P.; Kaye, A.; Nightingale, M.; Goulding, Richard H
Journal Name:
Fusion Engineering and Design
Page Number:
1953-1960
Volume:
84
Issue Number:
7-11
Publication Date:
July 2011
Conference Name:
25th Symposium on Fusion Technology
Conference Location:
Rostock, Germany
View DOI Listing:
https://doi.org/10.1016/j.fusengdes.2008.11.035

Abstract

Operating Ion Cyclotron Resonance Heating (ICRH) antennas at high power density puts them at risk of arcing which reduces the coupled power to the plasma because the perturbed impedance match triggers the Voltage Standing Wave Ratio (VWSR) based generator trip system but even worse might damage the antenna beyond repair because of the the arc’s localised energy deposition. New antennas are designed to operate in a load tolerant way which creates low impedance zones that are especially at risk since the existing VSWR protection systems are less sensitive to arcs in these areas. To protect these low impedance areas, a new arc protection system referred as Scattering Matrix Arc Detection (SMAD) was proposed. This paper describes the basic operating principle and implementation in hard- and software for the JET ITER-Like Antenna (ILA), with testbed and preliminary JET commissioning results.