1. ELM control experiments in the KSTAR device
- Author
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Kim, J, Kim, J, Jeon, YM, Xiao, WW, Yoon, SW, Park, JK, Yun, GS, Ahn, JW, Kim, HS, Yang, HL, Kim, HK, Park, S, Jeong, JH, Jung, M, Choe, GH, Ko, WH, Lee, SG, Nam, YU, Bak, JG, Lee, KD, Na, HK, Hahn, SH, Diamond, PH, Rhee, T, Kwon, JM, Sabbagh, SA, Park, YS, Park, HK, Na, YS, Kim, WC, Kwak, JG, Kim, J, Kim, J, Jeon, YM, Xiao, WW, Yoon, SW, Park, JK, Yun, GS, Ahn, JW, Kim, HS, Yang, HL, Kim, HK, Park, S, Jeong, JH, Jung, M, Choe, GH, Ko, WH, Lee, SG, Nam, YU, Bak, JG, Lee, KD, Na, HK, Hahn, SH, Diamond, PH, Rhee, T, Kwon, JM, Sabbagh, SA, Park, YS, Park, HK, Na, YS, Kim, WC, and Kwak, JG
- Abstract
The fourth KSTAR campaign in 2011 concentrated on active edge-localized mode (ELM) control by various methods such as non-axisymmetric magnetic perturbations, supersonic molecular beam injection (SMBI), vertical jogs of the plasma column and edge electron heating. The segmented in-vessel control coil (IVCC) system is capable of applying n2 perturbed field with different phasing among top, middle and bottom coils. Application of an n=1 perturbed field showed a desirable ELM suppression result. Fast vertical jogs of the plasma column achieved ELM pace-making and ELMs locked to 50Hz vertical jogs were observed with a high probability of phase locking. A newly installed SMBI system was used for ELM control and the state of mitigated ELMs was sustained by the optimized repetitive SMBI pulse for a few tens of ELM periods. A change in ELM behaviour was seen due to edge electron heating although the effect of ECH launch needs supplementary analyses. The ECEI images of suppressed/mitigated ELM states showed apparent differences when compared with natural ELMy states. Further analyses are ongoing to explain the observed ELM control results. © 2012 IAEA, Vienna.
- Published
- 2012