DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: An upgrade of the magnetic diagnostic system of the DIII-D tokamak for non-axisymmetric measurements

Abstract

Here, the DIII-D tokamak magnetic diagnostic system has been upgraded to significantly expand the measurement of the plasma response to intrinsic and applied non-axisymmetric “3D” fields. The placement and design of 101 additional sensors allow resolution of toroidal mode numbers 1 ≤ n ≤ 3, and poloidal wavelengths smaller than MARS-F, IPEC, and VMEC magnetohydrodynamic (MHD) model predictions. Small 3D perturbations, relative to the equilibrium field (10–5 <δB/B0 <10–4), require sub-millimeter fabrication and installation tolerances. This high precision is achieved using electrical discharge machined components, and alignment techniques employing rotary laser levels and a coordinate measurement machine. A 16-bit data acquisition system is used in conjunction with analog signal-processing to recover non-axisymmetric perturbations. Co-located radial and poloidal field measurements allow up to 14.2 cm spatial resolution of poloidal structures (plasma poloidal circumference is ~ 500 cm). The function of the new system is verified by comparing the rotating tearing mode structure, measured by 31 BP fluctuation sensors, with that measured by the upgraded BR saddle loop sensors after the mode locks to the vessel wall. The result is a nearly identical 2/1 helical eigenstructure in both cases.

Authors:
 [1];  [2];  [2];  [2];  [2];  [3];  [4];  [1];  [2];  [3];  [2];  [2];  [2];  [4];  [5];  [6];  [7]
  1. Oak Ridge Institute for Science and Education, Oak Ridge, TN (United States)
  2. General Atomics, San Diego, CA (United States)
  3. Columbia Univ., New York, NY (United States)
  4. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  5. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  6. The Australia National Univ., Canberra, ACT (Australia)
  7. National Fusion Research Center, Daejeon (South Korea)
Publication Date:
Research Org.:
General Atomics, San Diego, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1351085
Grant/Contract Number:  
FC02-04ER54698
Resource Type:
Accepted Manuscript
Journal Name:
Review of Scientific Instruments
Additional Journal Information:
Journal Volume: 85; Journal Issue: 8; Journal ID: ISSN 0034-6748
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

King, Joshua D., Strait, Edward J., Boivin, Rejean L., Taussig, Doug, Watkins, Matthias G., Hanson, Jeremy M., Logan, Nikolas C., Paz-Soldan, Carlos, Pace, David C., Shiraki, Daisuke, Lanctot, M. J., La Haye, R. J., Lao, L. L., Battaglia, D. J., Sontag, A. C., Haskey, S. R., and Bak, J. G. An upgrade of the magnetic diagnostic system of the DIII-D tokamak for non-axisymmetric measurements. United States: N. p., 2014. Web. doi:10.1063/1.4891817.
King, Joshua D., Strait, Edward J., Boivin, Rejean L., Taussig, Doug, Watkins, Matthias G., Hanson, Jeremy M., Logan, Nikolas C., Paz-Soldan, Carlos, Pace, David C., Shiraki, Daisuke, Lanctot, M. J., La Haye, R. J., Lao, L. L., Battaglia, D. J., Sontag, A. C., Haskey, S. R., & Bak, J. G. An upgrade of the magnetic diagnostic system of the DIII-D tokamak for non-axisymmetric measurements. United States. https://doi.org/10.1063/1.4891817
King, Joshua D., Strait, Edward J., Boivin, Rejean L., Taussig, Doug, Watkins, Matthias G., Hanson, Jeremy M., Logan, Nikolas C., Paz-Soldan, Carlos, Pace, David C., Shiraki, Daisuke, Lanctot, M. J., La Haye, R. J., Lao, L. L., Battaglia, D. J., Sontag, A. C., Haskey, S. R., and Bak, J. G. Thu . "An upgrade of the magnetic diagnostic system of the DIII-D tokamak for non-axisymmetric measurements". United States. https://doi.org/10.1063/1.4891817. https://www.osti.gov/servlets/purl/1351085.
@article{osti_1351085,
title = {An upgrade of the magnetic diagnostic system of the DIII-D tokamak for non-axisymmetric measurements},
author = {King, Joshua D. and Strait, Edward J. and Boivin, Rejean L. and Taussig, Doug and Watkins, Matthias G. and Hanson, Jeremy M. and Logan, Nikolas C. and Paz-Soldan, Carlos and Pace, David C. and Shiraki, Daisuke and Lanctot, M. J. and La Haye, R. J. and Lao, L. L. and Battaglia, D. J. and Sontag, A. C. and Haskey, S. R. and Bak, J. G.},
abstractNote = {Here, the DIII-D tokamak magnetic diagnostic system has been upgraded to significantly expand the measurement of the plasma response to intrinsic and applied non-axisymmetric “3D” fields. The placement and design of 101 additional sensors allow resolution of toroidal mode numbers 1 ≤ n ≤ 3, and poloidal wavelengths smaller than MARS-F, IPEC, and VMEC magnetohydrodynamic (MHD) model predictions. Small 3D perturbations, relative to the equilibrium field (10–5 <δB/B0 <10–4), require sub-millimeter fabrication and installation tolerances. This high precision is achieved using electrical discharge machined components, and alignment techniques employing rotary laser levels and a coordinate measurement machine. A 16-bit data acquisition system is used in conjunction with analog signal-processing to recover non-axisymmetric perturbations. Co-located radial and poloidal field measurements allow up to 14.2 cm spatial resolution of poloidal structures (plasma poloidal circumference is ~ 500 cm). The function of the new system is verified by comparing the rotating tearing mode structure, measured by 31 BP fluctuation sensors, with that measured by the upgraded BR saddle loop sensors after the mode locks to the vessel wall. The result is a nearly identical 2/1 helical eigenstructure in both cases.},
doi = {10.1063/1.4891817},
journal = {Review of Scientific Instruments},
number = 8,
volume = 85,
place = {United States},
year = {Thu Aug 07 00:00:00 EDT 2014},
month = {Thu Aug 07 00:00:00 EDT 2014}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 54 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Principles of Plasma Diagnostics
book, January 2009


Chapter 2: Magnetic Diagnostics
journal, February 2008

  • Strait, E. J.; Fredrickson, E. D.; Moret, J. -M.
  • Fusion Science and Technology, Vol. 53, Issue 2
  • DOI: 10.13182/FST08-A1674

Suppression of Large Edge-Localized Modes in High-Confinement DIII-D Plasmas with a Stochastic Magnetic Boundary
journal, June 2004


Observation of Plasma Rotation Driven by Static Nonaxisymmetric Magnetic Fields in a Tokamak
journal, November 2008


Plasma rotation driven by static nonresonant magnetic fields
journal, May 2009

  • Garofalo, A. M.; Solomon, W. M.; Lanctot, M.
  • Physics of Plasmas, Vol. 16, Issue 5
  • DOI: 10.1063/1.3129164

Feedback Stabilization of Multiple Resistive Wall Modes
journal, November 2004


Active-Feedback Control of the Magnetic Boundary for Magnetohydrodynamic Stabilization of a Fusion Plasma
journal, August 2006


Measurement of the Resistive-Wall-Mode Stability in a Rotating Plasma Using Active MHD Spectroscopy
journal, September 2004


Validation of the linear ideal magnetohydrodynamic model of three-dimensional tokamak equilibria
journal, March 2010

  • Lanctot, M. J.; Reimerdes, H.; Garofalo, A. M.
  • Physics of Plasmas, Vol. 17, Issue 3
  • DOI: 10.1063/1.3335237

Mode locking in tokamaks
journal, December 1990


Measurement of the electromagnetic torque in rotating DIII-D plasmas
journal, March 2010


Equilibrium analysis of current profiles in tokamaks
journal, June 1990


A review of Alfvén eigenmode observations in toroidal plasmas
journal, January 1999


Control of the resistive wall mode with internal coils in the DIII–D tokamak
journal, November 2005


Active Stabilization of the Resistive-Wall Mode in High-Beta, Low-Rotation Plasmas
journal, July 2006


Stabilization of the external kink and the resistive wall mode
journal, October 2010


Feedback stabilization of nonaxisymmetric resistive wall modes in tokamaks. I. Electromagnetic model
journal, September 2000

  • Liu, Y. Q.; Bondeson, A.; Fransson, C. M.
  • Physics of Plasmas, Vol. 7, Issue 9
  • DOI: 10.1063/1.1287744

Computation of three-dimensional tokamak and spherical torus equilibria
journal, May 2007

  • Park, Jong-kyu; Boozer, Allen H.; Glasser, Alan H.
  • Physics of Plasmas, Vol. 14, Issue 5
  • DOI: 10.1063/1.2732170

Steepest-descent moment method for three-dimensional magnetohydrodynamic equilibria
journal, January 1983


Magnetic diagnostic system of the DIII-D tokamak
journal, February 2006

  • Strait, E. J.
  • Review of Scientific Instruments, Vol. 77, Issue 2
  • DOI: 10.1063/1.2166493

Magnetic field pitch-angle measurments in the PBX-M tokamak using the motional Stark effect
journal, November 1989


An overview of charge-exchange spectroscopy as a plasma diagnostic
journal, February 1994


Multichordal charge‐exchange recombination spectroscopy on the DIII‐D tokamak
journal, August 1986

  • Seraydarian, Raymond P.; Burrell, Keith H.
  • Review of Scientific Instruments, Vol. 57, Issue 8
  • DOI: 10.1063/1.1138774

A multilaser system for a fast sampling Thomson scattering diagnostic
journal, October 1990

  • Trost, P. K.; Carlstrom, T. N.; DeBoo, J. C.
  • Review of Scientific Instruments, Vol. 61, Issue 10
  • DOI: 10.1063/1.1141808

Measurement and modeling of three-dimensional equilibria in DIII-D
journal, May 2011

  • Lanctot, M. J.; Reimerdes, H.; Garofalo, A. M.
  • Physics of Plasmas, Vol. 18, Issue 5
  • DOI: 10.1063/1.3593009

Anomalies in the applied magnetic fields in DIII-D and their implications for the understanding of stability experiments
journal, December 2003


Works referencing / citing this record:

Experimental tests of linear and nonlinear three-dimensional equilibrium models in DIII-D
journal, July 2015

  • King, J. D.; Strait, E. J.; Lazerson, S. A.
  • Physics of Plasmas, Vol. 22, Issue 7
  • DOI: 10.1063/1.4923017

Development of the saddle loop sensors on the J-TEXT tokamak
journal, October 2017

  • Guo, Daojing; Hu, Qiming; Li, Da
  • AIP Advances, Vol. 7, Issue 10
  • DOI: 10.1063/1.4993480

Predict-first experimental analysis using automated and integrated magnetohydrodynamic modeling
journal, May 2018

  • Lyons, B. C.; Paz-Soldan, C.; Meneghini, O.
  • Physics of Plasmas, Vol. 25, Issue 5
  • DOI: 10.1063/1.5025838

Modal analysis of the full poloidal structure of the plasma response to n = 2 magnetic perturbations
journal, July 2018

  • Munaretto, S.; Strait, E. J.; Haskey, S. R.
  • Physics of Plasmas, Vol. 25, Issue 7
  • DOI: 10.1063/1.5029381

Conceptual design of extended magnetic probe set to improve 3D field detection in NSTX-U
journal, October 2018

  • Munaretto, S.; Strait, E. J.; Lanctot, M. J.
  • Review of Scientific Instruments, Vol. 89, Issue 10
  • DOI: 10.1063/1.5036942

Two-fluid nonlinear theory of response of tokamak plasma to resonant magnetic perturbation
journal, November 2018


Direct measurements of internal structures of born-locked modes and the key role in triggering tokamak disruptions
journal, April 2019

  • Du, X. D.; Shafer, M. W.; Hu, Q. M.
  • Physics of Plasmas, Vol. 26, Issue 4
  • DOI: 10.1063/1.5085329

Equilibrium drives of the low and high field side n   =  2 plasma response and impact on global confinement
journal, April 2016


Effect of rotation zero-crossing on single-fluid plasma response to three-dimensional magnetic perturbations
journal, February 2017

  • Lyons, B. C.; Ferraro, N. M.; Paz-Soldan, C.
  • Plasma Physics and Controlled Fusion, Vol. 59, Issue 4
  • DOI: 10.1088/1361-6587/aa5860

Kink instabilities of the post-disruption runaway electron beam at low safety factor
journal, March 2019

  • Paz-Soldan, C.; Eidietis, N. W.; Liu, Y. Q.
  • Plasma Physics and Controlled Fusion, Vol. 61, Issue 5
  • DOI: 10.1088/1361-6587/aafd15

$\mathscr{H}_2$ optimal control techniques for resistive wall mode feedback in tokamaks
journal, February 2018


Relationship between locked modes and thermal quenches in DIII-D
journal, March 2018


The phase-space dependence of fast-ion interaction with tearing modes
journal, July 2018


Identification of multiple eigenmode growth rates in DIII-D and EAST tokamak plasmas
journal, January 2019


Alfvén eigenmodes and fast ion transport in negative triangularity DIII-D plasmas
journal, June 2019


Observation of a Multimode Plasma Response and its Relationship to Density Pumpout and Edge-Localized Mode Suppression
journal, March 2015


Pedestal Bifurcation and Resonant Field Penetration at the Threshold of Edge-Localized Mode Suppression in the DIII-D Tokamak
journal, March 2015