Abstract
The JT-60 Upgrade tokamak (JT-60U), can produce plasmas with vertical elongation ({kappa} {approx_equal} 1.6), and thus allows investigation of vertical instability phenomena. The present work describes investigation of the vertical stability characteristics of JT-60U plasmas through experimental results and simulation. Experiments described include feedback turnoff cases and high {beta}{sub p} unstable plasma cases. For purposes of simulation, the plasma is modeled as a rigid assembly of current-carrying axisymmetric loops. A nominal conductor model based on design geometry was modified to reproduce the results of a series of coil excitation experiments using a reduced order system identification approach. A two-coil model was used to fit the experimental coil excitation behavior, and the full order conductor model was modified to allow the dominant modes to reflect the low order dynamic response. The resulting plasma-conductor model is shown to reproduce the vertical stability behavior of JT-60U fairly well. Theoretical predictions of limits on the value of Shafranov {Lambda} achievable in JT-60U are made. (author).
Humphreys, D A;
Yoshino, Ryuji
[1]
- Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment
Citation Formats
Humphreys, D A, and Yoshino, Ryuji.
JT-60 Upgrade vertical stability experiments and analysis.
Japan: N. p.,
1992.
Web.
Humphreys, D A, & Yoshino, Ryuji.
JT-60 Upgrade vertical stability experiments and analysis.
Japan.
Humphreys, D A, and Yoshino, Ryuji.
1992.
"JT-60 Upgrade vertical stability experiments and analysis."
Japan.
@misc{etde_10111101,
title = {JT-60 Upgrade vertical stability experiments and analysis}
author = {Humphreys, D A, and Yoshino, Ryuji}
abstractNote = {The JT-60 Upgrade tokamak (JT-60U), can produce plasmas with vertical elongation ({kappa} {approx_equal} 1.6), and thus allows investigation of vertical instability phenomena. The present work describes investigation of the vertical stability characteristics of JT-60U plasmas through experimental results and simulation. Experiments described include feedback turnoff cases and high {beta}{sub p} unstable plasma cases. For purposes of simulation, the plasma is modeled as a rigid assembly of current-carrying axisymmetric loops. A nominal conductor model based on design geometry was modified to reproduce the results of a series of coil excitation experiments using a reduced order system identification approach. A two-coil model was used to fit the experimental coil excitation behavior, and the full order conductor model was modified to allow the dominant modes to reflect the low order dynamic response. The resulting plasma-conductor model is shown to reproduce the vertical stability behavior of JT-60U fairly well. Theoretical predictions of limits on the value of Shafranov {Lambda} achievable in JT-60U are made. (author).}
place = {Japan}
year = {1992}
month = {May}
}
title = {JT-60 Upgrade vertical stability experiments and analysis}
author = {Humphreys, D A, and Yoshino, Ryuji}
abstractNote = {The JT-60 Upgrade tokamak (JT-60U), can produce plasmas with vertical elongation ({kappa} {approx_equal} 1.6), and thus allows investigation of vertical instability phenomena. The present work describes investigation of the vertical stability characteristics of JT-60U plasmas through experimental results and simulation. Experiments described include feedback turnoff cases and high {beta}{sub p} unstable plasma cases. For purposes of simulation, the plasma is modeled as a rigid assembly of current-carrying axisymmetric loops. A nominal conductor model based on design geometry was modified to reproduce the results of a series of coil excitation experiments using a reduced order system identification approach. A two-coil model was used to fit the experimental coil excitation behavior, and the full order conductor model was modified to allow the dominant modes to reflect the low order dynamic response. The resulting plasma-conductor model is shown to reproduce the vertical stability behavior of JT-60U fairly well. Theoretical predictions of limits on the value of Shafranov {Lambda} achievable in JT-60U are made. (author).}
place = {Japan}
year = {1992}
month = {May}
}