Speaker
Tong Wang
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P2.1048.pdf
The rapid response of 2/1 tearing mode to electrode biasing in J-TEXT
experiments
Tong Wang1, Zhipeng Chen1,*, Qiming Hu2,*, Q. Yu3, Hai Liu4, Mingxiang Huang1, Jie
Yang1, Da Li1, Yuan Huang1, Daojing Guo1, Zhuo Huang1, Zhifeng Cheng1, Lizhi Zhu1,
Zhoujun Yang1 and J-TEXT Team
1
International Joint Research Laboratory of Magnetic Confinement Fusion and
Plasma Physics, State Key Laboratory of Advanced Electromagnetic Engineering and
Technology, 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
Max-Planck-Institut für Plasmaphysik, 85748, Garching, Germany
4
Institute of Fusion Science, Southwest Jiaotong University, Chengdu, 610031, China
*Corresponding author E-mail: zpchen@hust.edu.cn and qhu@pppl.gov
The effects of electrode biasing (EB) on the m/n = 2/1 tearing modes(TM) have been
experimentally studied in J-TEXT tokamak, where m and n are the poloidal and toroidal
mode numbers. According to the response time, the response of 2/1 tearing mode to EB can
be divided into two processes, the rapid response and the slow response. In the rapid response,
what needs to be noted is that the variation of EB current is proportional to the variation of
tearing mode frequency, regardless of the EB current rise time, position of electrode, and bias
voltage. On the base of that EB can supply a torque to change the tearing mode frequency
quickly, the EB has been applied to unlock the locked mode. The experimental results show
that the mode locking can be avoided by the negative bias voltage. While, it’s unfortunately
that the EB can’t unlock the locked mode in recent experiments, which is different from our
conjecture. In summary, the experimental results suggest that applied electrode biasing is a
possible method for the avoidance of mode locking and disruption.
