Progress towards steady-state operation and real-time control of internal transport barriers in JET
2003 (English)In: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 43, no 7, 565-572 p.Article in journal (Refereed) Published
In JET, advanced tokamak research mainly focuses on plasmas with internal transport barriers (ITBs) that are strongly influenced by the current density profile. A previously developed optimized shear regime with low magnetic shear in the plasma centre has been extended to deeply negative magnetic shear configurations. High fusion performance with wide ITBs has been obtained transiently with negative central magnetic shear configuration: H-IPB98(y,H-2) similar to 1.9, beta(N) = 2.4 at I-p = 2.5 MA. At somewhat reduced performance, electron and ion ITBs have been sustained in full current drive operation with 1 MA of bootstrap current: H-IPB98(y,H-2) similar to 1, beta(N) = 1.7 at I-p = 2.0 MA. The ITBs were maintained for up to 11 s for the latter case. This duration, much larger than the energy confinement time (37 times larger), is already approaching a current resistive time. New real-time measurements and feedback control algorithms have been developed and implemented in JET for successfully controlling the ITB dynamics and the current density profile in the highly non-inductive current regime.
Place, publisher, year, edition, pages
2003. Vol. 43, no 7, 565-572 p.
current-density profile, joint european torus, hybrid current drive, magnetic shear, high-performance, dt plasmas, stability, scenarios, supra, mode
IdentifiersURN: urn:nbn:se:kth:diva-22704ISI: 000184430400009OAI: oai:DiVA.org:kth-22704DiVA: diva2:341402
QC 201005252010-08-102010-08-10Bibliographically approved