In-vessel saddle coils for MHD control in ASDEX Upgrade
2009 (English)In: Fusion engineering and design, ISSN 0920-3796, Vol. 84, no 2-6, 290-294 p.Article in journal (Refereed) Published
A set of 24 in-vessel saddle coils is planned for MHD control experiments in ASDEX Upgrade. These coils can produce static and alternating error fields for suppression of Edge Localised Modes, locked mode rotation control and, together with additional conducting wall elements, resistive wall mode excitation and feedback stabilisation experiments. All of these applications address critical physics issues for the operation of ITER. This extension is implemented in several stages, starting with two poloidally separated rings of eight toroidally distributed saddle coils above and below the outer midplane. In stages 2 and 3, eight midplane coils around the large vessel access ports and 12 AC Power converters are added, respectively. Finally (stage 4), the existing passive stabilising loop (PSL), a passive conductor for vertical growth rate reduction, will be complemented by wall elements that allow helical Current patterns to reduce the RWM growth rate for active control within the accessible bandwidth. The system is capable of producing error fields with toroidal mode number n = 4 for plasma edge ergodisation with core island width well below the neo-classical tearing mode seed island width even without rotational shielding. Phase variation between the three toroidal coil rings allows to create or avoid resonances with the plasma safety factor profile, in order to test the importance of resonances for ELM suppression.
Place, publisher, year, edition, pages
Lausanne: ELSEVIER SCIENCE SA, , 2009. Vol. 84, no 2-6, 290-294 p.
Tokamaks, ASDEX Upgrade, MHD control, Edge Localised Modes, Locked mode, Resistive wall mode
Fusion, Plasma and Space Physics
IdentifiersURN: urn:nbn:se:kth:diva-25584DOI: 10.1016/j.fusengdes.2008.12.044ISI: 000267795600032ScopusID: 2-s2.0-67349171523OAI: oai:DiVA.org:kth-25584DiVA: diva2:371168
25th Symposium on Fusion Technology Rostock, GERMANY, SEP 15-19, 2008
QC 20101119(25th Symposium on Fusion Technology
Rostock, GERMANY, SEP 15-19, 2008)2010-11-192010-10-272011-03-16Bibliographically approved