The effects of plasma deformability on the feedback stabilization of axisymmetric modes in tokamak plasmas

Technical Report · Wed Jan 01 04:00:00 EST 1992

DOI:https://doi.org/10.2172/10115427· OSTI ID:10115427

Ward, D J ^[1]; Jardin, S C ^[2]

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1. Centre de Recherches en Physique des Plasmas, Lausanne (Switzerland)
2. Princeton Univ., NJ (United States). Plasma Physics Lab.

The effects of plasma deformability on the feedback stabilization of axisymmetric modes of tokamak plasmas are studied. It is seen that plasmas with strongly shaped cross sections have unstable motion different from a rigid shift. Furthermore, the placement of passive conductors is shown to modify the non-rigid components of the eigenfunction in a way that reduces the stabilizing eddy currents in these conductors. Passive feedback results using several equilibria of varying shape are presented. The eigenfunction is also modified under the effects of active feedback. This deformation is seen to depend strongly on the position of the flux loops which are used to determine plasma vertical position for the active feedback system. The variations of these non-rigid components of the eigenfunction always serve to reduce the stabilizing effect of the active feedback system by reducing the measurable poloidal flux at the flux-loop locations. Active feedback results are presented for the PBX-M tokamak configuration.

• Research Organization: Princeton Univ., NJ (United States). Plasma Physics Lab.
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC02-76CH03073
• OSTI ID: 10115427
• Report Number(s): PPPL--2805; ON: DE92006812
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700370
700410
ASPECT RATIO
AXIAL SYMMETRY
COMPACT IGNITION TOKAMAK
CONFINEMENT TIME
DEFORMATION
FEEDBACK
MAGNETIC FIELDS
MHD EQUILIBRIUM
PLASMA FLUID AND MHD PROPERTIES
SPECIFIC FUSION DEVICES AND EXPERIMENTS