Design and Tests of 500kW RF Windows for the ITER LHCD System - CEA - Commissariat à l’énergie atomique et aux énergies alternatives Access content directly
Journal Articles Fusion Engineering and Design Year : 2015

Design and Tests of 500kW RF Windows for the ITER LHCD System


In the frame of a R&D effort conducted by CEA toward the design and the qualification of a 5 GHz LHCD system for the ITER tokamak, two 5 GHz 500 kW/5 s windows have been designed, manufactured and tested at high power in collaboration with the National Fusion Research Institute (NFRI). The window design rely on a symmetrical pill-box concept with a cylindrical beryllium oxide ceramic brazed on an actively water cooled copper skirt. The ceramic RF properties have been measured on a test sample to get realistic values for guiding the design. Low power measurements of the manufactured windows show return losses below-32 dB and insertion losses between-0.01 dB and-0.05 dB, with an optimum frequency shifted toward lower frequencies. High power tests conducted at NFRI show unexpected total power loss for both windows. The ceramic temperature during RF pulses has been found to reach unexpected high temperature, preventing these windows to be used under CW conditions. A post-mortem RF analysis of samples taken from one window shows that the dielectric properties of the ceramic were not the ones measured on the manufacturer sample, which partly explain the differences with the reference modelling.


Fichier principal
Vignette du fichier
Hillairet_FED_5GHz_Window_Design_Corrected-Version2.pdf (1.99 Mo) Télécharger le fichier
Origin : Files produced by the author(s)

Dates and versions

cea-01132548 , version 1 (17-03-2015)



Julien Hillairet, J Kim, N Faure, J Achard, L Delpech, et al.. Design and Tests of 500kW RF Windows for the ITER LHCD System. Fusion Engineering and Design, 2015, pp.1. ⟨10.1016/j.fusengdes.2015.02.065⟩. ⟨cea-01132548⟩
161 View
916 Download



Gmail Facebook X LinkedIn More