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Suppression of MHD modes with active phase-control of probe-injected currents

Journal Article · · Nuclear Fusion
Abstract

Active phase-control of probe-injected current is shown to both suppress and amplify long-wavelength rotating magnetohydrodynamic instabilities in the HBT-EP tokamak. Four probes are connected in quadrature and energized to drive non-axisymmetric currents through the edge of the tokamak, creating magnetic perturbations comparable to previously-studied saturated kink modes or resonant magnetic perturbations that are generated by an external control coil array. Measurements of the magnetic perturbations from the probe-injected currents determine a set of current-carrying helical filaments used to model active feedback control of resistive wall modes. These experiments suggest current-injection feedback may be an effective alternative to external control coils for control of RWMs and other long-wavelength kink-like modes at the edge of tokamaks.

Research Organization:
Columbia Univ., New York, NY (United States); Univ. of Washington, Seattle, WA (United States)
Sponsoring Organization:
USDOE Office of Science (SC)
DOE Contract Number:
FG02-86ER53222; SC0021325
OSTI ID:
1849935
Journal Information:
Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 9 Vol. 61; ISSN 0029-5515
Publisher:
IOP Science
Country of Publication:
United States
Language:
English

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