Techniques for the measurement of disruption halo currents in the National Spherical Torus Experiment
Abstract
This paper describes techniques for measuring halo currents, and their associated toroidal peaking, in the National Spherical Torus Experiments. The measurements are based on three techniques: (i) measurement of the toroidal field created by the poloidal halo current, either with segmented Rogowski coils or discrete toroidal field sensors, (ii) the direct measurement of halo currents into specially instrument tiles, and (iii) small Rogowski coils placed on the mechanical supports of in-vessel components. For the segmented Rogowski coils and discrete toroidal field detectors, it is shown that the toroidal peaking factor inferred from the data is significantly less than the peaking factor of the underlying halo current distribution, and a simple model is developed to relate the two. For the array of discrete toroidal field detectors and small Rogowski sensors, the compensation steps that are used to isolate the halo current signal are described. The electrical and mechanical design of compact under-tile resistive shunts and mini-Rogowski coils is described. Example data from the various systems is shown.
- Authors:
-
- Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
- Princeton Fusion Research LLC, Princeton, NJ (United States)
- Publication Date:
- Research Org.:
- Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC)
- OSTI Identifier:
- 1076455
- Grant/Contract Number:
- AC02-09CH11466
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Review of Scientific Instruments
- Additional Journal Information:
- Journal Volume: 82; Journal Issue: 10; Journal ID: ISSN 0034-6748
- Publisher:
- American Institute of Physics (AIP)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; National Spherical Torus Experiment, NSTX, Halo Currents, Disruptions
Citation Formats
Gerhardt, S. P., Fredrickson, E., Guttadora, L., Kaita, R., Kugel, H., Menard, J., and Takahashi, H. Techniques for the measurement of disruption halo currents in the National Spherical Torus Experiment. United States: N. p., 2011.
Web. doi:10.1063/1.3642618.
Gerhardt, S. P., Fredrickson, E., Guttadora, L., Kaita, R., Kugel, H., Menard, J., & Takahashi, H. Techniques for the measurement of disruption halo currents in the National Spherical Torus Experiment. United States. https://doi.org/10.1063/1.3642618
Gerhardt, S. P., Fredrickson, E., Guttadora, L., Kaita, R., Kugel, H., Menard, J., and Takahashi, H. Thu .
"Techniques for the measurement of disruption halo currents in the National Spherical Torus Experiment". United States. https://doi.org/10.1063/1.3642618. https://www.osti.gov/servlets/purl/1076455.
@article{osti_1076455,
title = {Techniques for the measurement of disruption halo currents in the National Spherical Torus Experiment},
author = {Gerhardt, S. P. and Fredrickson, E. and Guttadora, L. and Kaita, R. and Kugel, H. and Menard, J. and Takahashi, H.},
abstractNote = {This paper describes techniques for measuring halo currents, and their associated toroidal peaking, in the National Spherical Torus Experiments. The measurements are based on three techniques: (i) measurement of the toroidal field created by the poloidal halo current, either with segmented Rogowski coils or discrete toroidal field sensors, (ii) the direct measurement of halo currents into specially instrument tiles, and (iii) small Rogowski coils placed on the mechanical supports of in-vessel components. For the segmented Rogowski coils and discrete toroidal field detectors, it is shown that the toroidal peaking factor inferred from the data is significantly less than the peaking factor of the underlying halo current distribution, and a simple model is developed to relate the two. For the array of discrete toroidal field detectors and small Rogowski sensors, the compensation steps that are used to isolate the halo current signal are described. The electrical and mechanical design of compact under-tile resistive shunts and mini-Rogowski coils is described. Example data from the various systems is shown.},
doi = {10.1063/1.3642618},
journal = {Review of Scientific Instruments},
number = 10,
volume = 82,
place = {United States},
year = {Thu Oct 06 00:00:00 EDT 2011},
month = {Thu Oct 06 00:00:00 EDT 2011}
}
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Works referencing / citing this record:
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