Active control of type-I edge localized modes on JET
2007 (English)In: Plasma Physics and Controlled Fusion, ISSN 0741-3335, E-ISSN 1361-6587, Vol. 49, no 12B, B581-B589 p.Article in journal (Refereed) Published
The operational domain for active control of type-I edge localized modes (ELMs) with an n = 1 external magnetic perturbation field induced by the ex-vessel error field correction coils on JET has been developed towards more ITER-relevant regimes with high plasma triangularity, up to 0.45, high normalized beta, up to 3.0, plasma current up to 2.0 MA and q(95) varied between 3.0 and 4.8. The results of ELM mitigation in high triangularity plasmas show that the frequency of type-I ELMs increased by a factor of 4 during the application of the n = 1 fields, while the energy loss per ELM, Delta W/W, decreased from 6% to below the noise level of the diamagnetic measurement (<2%). No reduction of confinement quality (H98Y) during the ELM mitigation phase has been observed. The minimum n = 1 perturbation field amplitude above which the ELMs were mitigated increased with a lower q(95) but always remained below the n = 1 locked mode threshold. The first results of ELM mitigation with n = 2 magnetic perturbations on JET demonstrate that the frequency of ELMs increased from 10 to 35 Hz and a wide operational window of q95 from 4.5 to 3.1 has been found.
Place, publisher, year, edition, pages
2007. Vol. 49, no 12B, B581-B589 p.
IdentifiersURN: urn:nbn:se:kth:diva-40763DOI: 10.1088/0741-3335/49/12B/S54ISI: 000252745900056ScopusID: 2-s2.0-36348988366OAI: oai:DiVA.org:kth-40763DiVA: diva2:443167
34th European-Physical-Society Conference on Plasma Physics Location: Palace Culture & Sci, Warsaw, Poland, Date: JUL 02-06, 2007 2011-09-232011-09-202011-09-23Bibliographically approved