Resonant magnetic perturbation effect on tearing mode dynamics
2010 (English)In: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 50, no 3, 035005- p.Article in journal (Refereed) Published
The effect of a resonant magnetic perturbation (RMP) on the tearing mode (TM) dynamics is experimentally studied in the EXTRAP T2R device. EXTRAP T2R is equipped with a set of sensor coils and active coils connected by a digital controller allowing a feedback control of the magnetic instabilities. The recently upgraded feedback algorithm allows the suppression of all the error field harmonics but keeping a selected harmonic to the desired amplitude, therefore opening the possibility of a clear study of the RMP effect on the corresponding TM. The paper shows that the RMP produces two typical effects: (1) a weak oscillation in the TM amplitude and a modulation in the TM velocity or (2) a strong modulation in the TM amplitude and phase jumps. Moreover, the locking mechanism of a TM to a RMP is studied in detail. It is shown that before the locking, the TM dynamics is characterized by velocity modulation followed by phase jumps. Experimental results are reasonably explained by simulations obtained with a model.
Place, publisher, year, edition, pages
2010. Vol. 50, no 3, 035005- p.
REVERSED-FIELD PINCH, TOROIDAL PINCH, ACTIVE CONTROL, SELF-ORGANIZATION, RESISTIVE WALL, TOKAMAK, ISLANDS, PLASMAS, STABILIZATION, LOCKING
Fusion, Plasma and Space Physics
IdentifiersURN: urn:nbn:se:kth:diva-29932DOI: 10.1088/0029-5515/50/3/035005ISI: 000275619700019ScopusID: 2-s2.0-77149131504OAI: oai:DiVA.org:kth-29932DiVA: diva2:398376
QC 20110217 4th Workshop on Stochasticity in Fusion Plasmas, Julich, GERMANY, MAR 02-04, 20092011-02-172011-02-172011-02-17Bibliographically approved