Stabilization of the resistive wall mode using a fake rotating shell

Fitzpatrick, R; Jensen, T H

doi:10.2172/171361

Title: Stabilization of the resistive wall mode using a fake rotating shell

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Abstract

Tokamak plasma performance can, in theory, be greatly improved if the so called resistive wall mode is stabilized. This can be achieved by spinning the plasma rapidly, but such a scheme is not reactor relevant. A more promising approach is to apply external feedback in order to make a resistive shell placed around the plasma act like a perfect conductor. A scheme is outlined by which a network of feedback controlled conductors surrounding the plasma can be made to act like a rotating shell. This fake rotating shell combined with a stationary conventional shell (e.g. the vacuum vessel) can completely stabilize the resistive wall mode. The gain, bandwidth, current, and power requirements of the feedback amplifiers are extremely modest. A previously proposed stabilization scheme (the intelligent shell) is also investigated, and is compared with the fake rotating shell concept. The main disadvantage of the former scheme is that it requires a high gain.

Authors:

Fitzpatrick, R ^[1]; Jensen, T H ^[2]

Texas Univ., Austin, TX (United States). Inst. for Fusion Studies
General Atomics, La Jolla, CA (United States)

Publication Date:: Wed Nov 01 00:00:00 EST 1995

Research Org.:: Univ. of Texas, Austin, TX (United States). Institute for Fusion Studies

Sponsoring Org.:: USDOE, Washington, DC (United States)

OSTI Identifier:: 171361

Report Number(s):: DOE/ET/53088-733; IFSR-733
ON: DE96003969; TRN: 96:003720

DOE Contract Number:: FG05-80ET53088; AC03-89ER51114

Resource Type:: Technical Report

Resource Relation:: Other Information: PBD: Nov 1995

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION; TOKAMAK DEVICES; PLASMA INSTABILITY; STABILIZATION; ELECTRIC CONDUCTORS; ROTATION; KINK INSTABILITY; VACUUM SYSTEMS; COMPARATIVE EVALUATIONS

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                    Fitzpatrick, R, and Jensen, T H. Stabilization of the resistive wall mode using a fake rotating shell.  United States: N. p., 1995. 
        Web.  doi:10.2172/171361.

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                    Fitzpatrick, R, & Jensen, T H. Stabilization of the resistive wall mode using a fake rotating shell.  United States.  https://doi.org/10.2172/171361

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                    Fitzpatrick, R, and Jensen, T H. 1995.  
        "Stabilization of the resistive wall mode using a fake rotating shell".  United States.  https://doi.org/10.2172/171361.  https://www.osti.gov/servlets/purl/171361.

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@article{osti_171361,

  title        = {Stabilization of the resistive wall mode using a fake rotating shell},

  author       = {Fitzpatrick, R and Jensen, T H},

  abstractNote = {Tokamak plasma performance can, in theory, be greatly improved if the so called resistive wall mode is stabilized. This can be achieved by spinning the plasma rapidly, but such a scheme is not reactor relevant. A more promising approach is to apply external feedback in order to make a resistive shell placed around the plasma act like a perfect conductor. A scheme is outlined by which a network of feedback controlled conductors surrounding the plasma can be made to act like a rotating shell. This fake rotating shell combined with a stationary conventional shell (e.g. the vacuum vessel) can completely stabilize the resistive wall mode. The gain, bandwidth, current, and power requirements of the feedback amplifiers are extremely modest. A previously proposed stabilization scheme (the intelligent shell) is also investigated, and is compared with the fake rotating shell concept. The main disadvantage of the former scheme is that it requires a high gain.},

  doi          = {10.2172/171361},

  url          = {https://www.osti.gov/biblio/171361},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Wed Nov 01 00:00:00 EST 1995},

  month        = {Wed Nov 01 00:00:00 EST 1995}

}

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https://doi.org/10.2172/171361

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