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Improved plasma position detection method in EAST Tokamak using fast CCD camera

  • Shuang-Bao Shu
  • Chuan-Mu Yu
  • Chao Liu
  • Mei-Wen Chen
  • Yu-Zhong ZhangEmail author
  • Xin Li
Article
  • 20 Downloads

Abstract

To control the steady-state operation of Tokamak plasma, it is crucial to accurately obtain its shape and position. This paper presents a method for use in rapidly detecting plasma configuration during discharge of the Experimental Advanced Superconducting Tokamak device. First, a visible/infrared integrated endoscopy diagnostic system with a large field of view is introduced, and the PCO.edge5.5 camera in this system is used to acquire a plasma discharge image. Based on the analysis of various traditional edge detection algorithms, an improved wavelet edge detection algorithm is then introduced to identify the edge of the plasma. In this method, the local maximum of the modulus of wavelet transform is searched along four gradient directions, and the adaptive threshold is adopted. Finally, the detected boundary is fitted using the least square iterative method to accurately obtain the position of the plasma. Experimental results obtained using the EAST device show that the method presented in this paper can realize expected goals and produce ideal effects; this method thus has significant potential for application in further feedback control of plasma.

Keywords

Experimental Advanced Superconducting Tokamak (EAST) Plasma CCD camera Edge detection 

Notes

Acknowledgements

The authors are grateful to all members of the EAST team for their contribution to experiments.

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Copyright information

© China Science Publishing & Media Ltd. (Science Press), Shanghai Institute of Applied Physics, the Chinese Academy of Sciences, Chinese Nuclear Society and Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  • Shuang-Bao Shu
    • 1
  • Chuan-Mu Yu
    • 1
  • Chao Liu
    • 1
  • Mei-Wen Chen
    • 2
  • Yu-Zhong Zhang
    • 1
    Email author
  • Xin Li
    • 1
  1. 1.School of Instrument Science and Opto-electronics EngineeringHefei University of TechnologyHefeiChina
  2. 2.China Institute of Plasma PhysicsChinese Academy of SciencesHefeiChina

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