Speaker
Da Li
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P1.1110.pdf
Avoiding disruption via the locked mode control by the rotating RMP on
J-TEXT tokamak
Da Li1, Yonghua Ding1,*,Feiran Hu1, Tong Wang1, Lizhi Zhu1, Nengchao Wang1, Bo Rao1,
Qiming Hu2, Hai Jin3, Zhuo Huang1, Mao Li1, Song Zhou1, Ruo Jia1, Lai Peng1, Zebao
Song1, Ying He1, Jiaolong Dong, Chengshuo Shen1 and the J-TEXT team
1
International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma
Physics, School of Electrical and Electronic Engineering, Huazhong University of Science
and Technology, Wuhan, 430074, China
2
Princeton Plasma Physics Laboratory, Princeton NJ 08543-0451, USA
3
College of Electrical and Information Engineering, Lanzhou University of Technology,
Lanzhou 730050, China
*E-mail: yhding@hust.edu.cn
In a tokamak, one of the major causes of disruptions is locked mode (LM), a static
tearing mode which usually grows to large amplitudes. Therefore, the active control of the
LM is an important issue for future fusion reactors. Previously, we have reported the
unlocking of the LM by rotating resonant magnetic perturbation (RMP), which rotated at
several kHz [1]
. In Ref. [1], the m/n = 2/1 LM was too small to induce disruption, where m
and n are the poloidal and toroidal mode numbers, respectively.
In this paper, we will use rotating RMP to control the larger 2/1 LM and to avoid the
disruption in J-TEXT tokamak. The electrode biasing (EB) could decelerate the tearing
mode (TM) and cause the LM . A major disruption usually occurred within 5 ~ 20 ms
[2]
after the mode locking due to EB. The rotating RMP, applied once the appearance of a LM,
could accelerate the LM to a few kHz and hence avoid the disruption. However, when the
LM was quite large at lower qa, it is really difficult to unlock the LM by rotating RMP. To
improve the performance of the rotating RMP, it was applied once the TM was decelerated
by the EB to a critical value. This control strategy could accelerate the TM, avoid the
appearance of LM and disruption. Further experiments showed that rotating RMP at higher
frequency had better performance in controlling the disruption.
[1] Hai Jin et al 2015 Plasma Phys. Control. Fusion 57 104007
[2] Hai Liu et al 2017 Nucl. Fusion 57 0160
