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arXiv · 1603.01506

Ion cyclotron resonance heating systems upgrade toward high power and CW operations in WEST

Abstract

The design of the WEST (Tungsten-W Environment in Steady-state Tokamak) Ion cyclotron resonance heating antennas is based on a previously tested conjugate-T Resonant Double Loops prototype equipped with internal vacuum matching capacitors. The design and construction of three new WEST ICRH antennas are being carried out in close collaboration with ASIPP, within the framework of the Associated Laboratory in the fusion field between IRFM and ASIPP. The coupling performance to the plasma and the load-tolerance have been improved, while adding Continuous Wave operation capability by introducing water cooling in the entire antenna. On the generator side, the operation class of the high power tetrodes is changed from AB to B in order to allow high power operation (up to 3 MW per antenna) under higher VSWR (up to 2:1). Reliability of the generators is also improved by increasing the cavity breakdown voltage. The control and data acquisition system is also upgraded in order to resolve and react on fast events, such as ELMs. A new optical arc detection system comes in reinforcement of the V r /V f and SHAD systems.

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Julien Hillairet, Patrick Mollard, Yanping Zhao, Jean-Michel Bernard, Yuntao Song, Arnaud Argouarch, Gilles Berger-By, Nicolas Charabot, Gen Chen, Zhaoxi Chen, Laurent Colas, Jean-Marc Delaplanche, Pierre Dumortier, Frédéric Durodié, Annika Ekedahl, Nicolas Fedorczak, Fabien Ferlay, Marc Goniche, Jean-Claude Hatchressian, Walid Helou, Jonathan Jacquot, Emmanuel Joffrin, Xavier Litaudon, Gilles Lombard, Riccardo Maggiora, Roland Magne, Daniele Milanesio, Jean-Claude Patterlini, Marc Prou, Jean-Marc Verger, Robert Volpe, Karl Vulliez, Yongsheng Wang, Konstantin Winkler, Qingxi Yang, Shuai Yuan. 2016-03-04. Ion cyclotron resonance heating systems upgrade toward high power and CW operations in WEST. https://doi.org/10.1063/1.4936512

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