5-9 September 2016
Prague Congress Centre
Europe/Prague timezone

P3.029 EMC improvement of an ECH power supplies system at TCV

7 Sep 2016, 11:00
1h 20m
Foyer 2A (2nd floor), 3A (3rd floor) (Prague Congress Centre)

Foyer 2A (2nd floor), 3A (3rd floor)

Prague Congress Centre

5. května 65, Prague, Czech Republic
Board: 29
Poster B. Plasma Heating and Current Drive P3 Poster session

Speaker

Ugo Siravo (Ecole Polytechnique Fédérale de Lausanne (EPFL))

Description

Three RHVPSs (Regulated High Voltage Power Supplies, 84kV/80A/2s) are installed and operated at the Swiss Plasma Center for almost twenty years. Each RHVPS supplies a cluster of three gyrotrons. Two clusters are composed of diode type gyrotrons operating at the second harmonic of the TCV electron-cyclotron frequency (X2, 84GHz), whereas the third is a cluster of triode type gyrotrons operating at the third harmonic (X3, 118GHz) [1]. During the ECH HVPSs design and installation period, grounding was mainly considered from the safety point of view. EMC (Electro Magnetic Compatibility) was not a major concern; so, the ECH plant operation was producing important electromagnetic interferences. In previous work, the MPS (Modulator Power Supply), which controls the anode to cathode voltage of X3 gyrotrons, was upgraded to improve its output voltage quality [2]. A new control system was also implemented [3]. The upgrade aimed to allow operating the X3 gyrotrons in a more reliable way and to achieve real-time X3 RF power tuning. Subsequently, it has been necessary to understand why operation of the X3 cluster was not successful (occurrences of mode jumps or arcs in the gyrotrons) when its RHVPS was driven by an external voltage reference, whereas the X2 clusters have always been able to operate in this way. This paper focuses on the EMC problems inherent to power converters. The mechanism by which these converters influence their environment is explained. Solutions to minimize the emission of interferences are given. Finally, first results of real-time X3 RF power tuning during TCV shots are shown. These improvements make possible extended TCV heating scenarios. [1] D. Fasel et al., Proc. 19th SOFT, September 1996, p. 569-572[2] U. Siravo et al., Fusion Engineering And Design, vol. 96-97, October 2015, p. 597-601[3] J. Dubray et al., this conference

Co-authors

Alberto Perez (Ecole Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland) Damien Fasel (Ecole Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland) Jeremie Dubray (Ecole Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland) Miguel Silva (Ecole Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland) Tim Goodman (Ecole Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland) Ugo Siravo (Ecole Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland)

Presentation Materials

There are no materials yet.