- Kim, Jayhyun;
- Jeon, Y-M;
- Xiao, WW;
- Yoon, S-W;
- Park, J-K;
- Yun, GS;
- Ahn, J-W;
- Kim, HS;
- Yang, H-L;
- Kim, HK;
- Park, S;
- Jeong, JH;
- Jung, M;
- Choe, GH;
- Ko, WH;
- Lee, S-G;
- Nam, YU;
- Bak, JG;
- Lee, KD;
- Na, HK;
- Hahn, S-H;
- Diamond, PH;
- Rhee, T;
- Kwon, JM;
- Sabbagh, SA;
- Park, YS;
- Park, HK;
- Na, YS;
- Kim, WC;
- Kwak, JG
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.