NSTX-U In-Vessel Control Coils’ Design Concept

Atnafu, Neway D.; Brooks, A.; Cai, D.; Dellas, J.; Gerhardt, S.; Menard, J.; Ono, M.; Labik, G.; Titus, P.; Gonzalez-Teodoro, Jorge R.

doi:10.1109/TPS.2018.2822555

Title: NSTX-U In-Vessel Control Coils’ Design Concept

Abstract

In this paper, a successful conceptual design was completed to develop in-vessel control coils [non-axisymmetric control coils (NCCs)]. The NCCs are a series of saddle coils that are intended to satisfy a number of physics criteria including magnetic breaking, error field control, fast resistive wall mode (RWM) control, and edge-localized-mode stabilization. Customized mineral-insulated cable (MIC) was selected for the conductor material. The MIC was made from oxygen-free copper conductor, high purity magnesium oxide powder insulation, and 304 stainless steel sleeve cover. Sample MIC was purchased from an outside supplier, and various tests were conducted for design and performance verification including high-voltage testing, which necessitated the development of special test terminations. A concept design was also developed for terminating the MIC ends using the nonconductive and vacuum-sealed technique. Two alternative designs were proposed for joints inside the vacuum vessel (VV). The NCCs are designed to be mounted in front of the primary passive plates and underneath the plasma-facing component (PFC) tiles. The passive plates will be modified to accommodate the coils. A new PFC tile design concept was developed using high-Z materials. New designs for the penetrations through the VV wall were developed. One port per coil was planned. Finally, amore »« less

Authors:

^[1]; Brooks, A. ^[1];

^[1];

^[1]; Gerhardt, S. ^[1]; Menard, J. ^[1]; Ono, M. ^[1]; Labik, G. ^[1];

^[1];

^[1]

Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Publication Date:: 2018-04-26

Research Org.:: Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1465669

Grant/Contract Number:: AC02-09CH11466

Resource Type:: Accepted Manuscript

Journal Name:: IEEE Transactions on Plasma Science

Additional Journal Information:: Journal Volume: 46; Journal Issue: 5; Journal ID: ISSN 0093-3813

Publisher:: IEEE

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 42 ENGINEERING; control coils; fusion diagnostics; in-vessel coils; mineral-insulated cable (MIC)

Citation Formats


                    Atnafu, Neway D., Brooks, A., Cai, D., Dellas, J., Gerhardt, S., Menard, J., Ono, M., Labik, G., Titus, P., and Gonzalez-Teodoro, Jorge R. NSTX-U In-Vessel Control Coils’ Design Concept.  United States: N. p., 2018. 
Web.  doi:10.1109/TPS.2018.2822555.

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                    Atnafu, Neway D., Brooks, A., Cai, D., Dellas, J., Gerhardt, S., Menard, J., Ono, M., Labik, G., Titus, P., & Gonzalez-Teodoro, Jorge R. NSTX-U In-Vessel Control Coils’ Design Concept.  United States.  https://doi.org/10.1109/TPS.2018.2822555

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                    Atnafu, Neway D., Brooks, A., Cai, D., Dellas, J., Gerhardt, S., Menard, J., Ono, M., Labik, G., Titus, P., and Gonzalez-Teodoro, Jorge R. Thu .  
"NSTX-U In-Vessel Control Coils’ Design Concept".  United States.  https://doi.org/10.1109/TPS.2018.2822555.  https://www.osti.gov/servlets/purl/1465669.

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@article{osti_1465669,

  title        = {NSTX-U In-Vessel Control Coils’ Design Concept},

  author       = {Atnafu, Neway D. and Brooks, A. and Cai, D. and Dellas, J. and Gerhardt, S. and Menard, J. and Ono, M. and Labik, G. and Titus, P. and Gonzalez-Teodoro, Jorge R.},

  abstractNote = {In this paper, a successful conceptual design was completed to develop in-vessel control coils [non-axisymmetric control coils (NCCs)]. The NCCs are a series of saddle coils that are intended to satisfy a number of physics criteria including magnetic breaking, error field control, fast resistive wall mode (RWM) control, and edge-localized-mode stabilization. Customized mineral-insulated cable (MIC) was selected for the conductor material. The MIC was made from oxygen-free copper conductor, high purity magnesium oxide powder insulation, and 304 stainless steel sleeve cover. Sample MIC was purchased from an outside supplier, and various tests were conducted for design and performance verification including high-voltage testing, which necessitated the development of special test terminations. A concept design was also developed for terminating the MIC ends using the nonconductive and vacuum-sealed technique. Two alternative designs were proposed for joints inside the vacuum vessel (VV). The NCCs are designed to be mounted in front of the primary passive plates and underneath the plasma-facing component (PFC) tiles. The passive plates will be modified to accommodate the coils. A new PFC tile design concept was developed using high-Z materials. New designs for the penetrations through the VV wall were developed. One port per coil was planned. Finally, a new power patch panel will be required to provide the ability for various combinations of connections between the NCC, the existing RWM coils, and the existing switching power amplifier power suppliers.},

  doi          = {10.1109/TPS.2018.2822555},

  journal      = {IEEE Transactions on Plasma Science},

  number       = 5,

  volume       = 46,

  place        = {United States},

  year         = {2018},

  month        = {4}

}

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Journal Article:

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https://doi.org/10.1109/TPS.2018.2822555

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Figures / Tables:

Fig. 1: In Vessel coils Distribution.

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