Measurement of the effects of Faraday shields on ICRH antenna coupling

Journal Article · Sun Apr 01 04:00:00 EDT 1990 · IEEE Transactions on Plasma Science (Institute of Electrical and Electronics Engineers); (USA)

DOI:https://doi.org/10.1109/27.131018· OSTI ID:6682644

Kwon, M; Thomas, Jr, C E ^[1]; Hoffman, D J; Shepard, T D ^[2]; Rettig, C L ^[3]

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1. Georgia Inst. of Tech., Atlanta, GA (USA). Nuclear Engineering Dept.
2. Oak Ridge National Lab., TN (USA)
3. California Univ., Los Angeles, CA (USA)

Compact loop antennas are being applied to several fusion experiments. Although individual configurations vary, all of these antennas generally comprise a current strap in a recessed box and a Faraday shield. The effect of the cross-sectional shape of the current strap on voltage and current levels was measured. In this work the coupling characteristics of cavity antennas that have current straps with the previously evaluated cross-sectional shapes re tested with several Faraday shields. Impedances and relative fields are measured for various combinations of the current strap and Faraday shield. The experiments show that the fractional reduction in the magnetic flux linkage to the plasma resulting from the addition of any particular Faraday shield i virtually independent of the shape of the current strap. This is true in spite of the fact that the same mechanism which is responsible for the reduction in flux is also responsible for a significant redistribution of the antenna current on the current strap. Thus the process of optimizing antennas is reduced to that of separately optimizing the current strap and Faraday shield.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6682644
• Journal Information: IEEE Transactions on Plasma Science (Institute of Electrical and Electronics Engineers); (USA), Journal Name: IEEE Transactions on Plasma Science (Institute of Electrical and Electronics Engineers); (USA) Vol. 18:2; ISSN ITPSB; ISSN 0093-3813
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700101* -- Fusion Energy-- Plasma Research-- Confinement
Heating
& Production
ANTENNAS
BEAM MONITORS
CURRENTS
ELECTRIC CURRENTS
ELECTRICAL EQUIPMENT
EQUIPMENT
FARADAY CUPS
FARADAY CURRENT
FARADAY EFFECT
HEATING
HIGH-FREQUENCY HEATING
ICR HEATING
MAGNETIC FLUX
MEASURING INSTRUMENTS
MEASURING METHODS
MONITORS
PLASMA HEATING
TFTR TOKAMAK
THERMONUCLEAR REACTORS
TOKAMAK TYPE REACTORS