Plasma and Fusion Research

Volume 14, 3403151 (2019)

Regular Articles

Consideration of the Influence of Coil Misalignment on the Chinese First Quasi-Axisymmetric Stellarator Magnetic Configuration
Akihiro SHIMIZU1), Haifeng LIU2), Shigeyoshi KINOSHITA1), Mitsutaka ISOBE1,3), Shoichi OKAMURA1), Kunihiro OGAWA1,3), Motoki NAKATA1,3), Shinsuke SATAKE1,3), Chihiro SUZUKI1), Guozhen XIONG2), Yuhong XU2), Hai LIU2), Xin ZHANG2), Jie HUANG2), Xianqu WANG2), Changjian TANG4), Dapeng YIN5), Yi WAN5) and CFQS Team1,2,3,5)
National Institute for Fusion Science, National Institutes of Natural Sciences, Toki 509-5292, Japan
Institute of Fusion Science, School of Physical Science and Technology, Southwest Jiaotong University, Chengdu 610031, China
SOKENDAI (The Graduate University for Advanced Studies), Toki 509-5292, Japan
School of Physical Science and Technology, Sichuan University, Chengdu 610041, China
Hefei Keye Electro Physical Equipment Manufacturing Co., Ltd, Hefei 230000, China
(Received 10 January 2019 / Accepted 20 May 2019 / Published 25 September 2019)


The effects of misalignment of modular coils on various physical properties in the Chinese first quasi-axisymmetric Stellarator (CFQS) are discussed in this study. To estimate the effects quantitatively, simple assumptions are made regarding the structure of coil displacement. We consider the following three cases: displacement in radial direction (Case A), displacement in the vertical direction (Case B), and displacement by tilting (Case C). In all cases, we assume that the displacement structure has a stellarator symmetry. These assumptions are employed to calculate the change in the magnetic surfaces, rotational transform profile, magnetic well depth profile, and the effective helical ripple. Calculation results show that if the magnitude of displacement is less than 10 mm, the effects on these physical properties are small, and the good neoclassical transport property is retained.


quasi-axisymmetric stellarator, the Chinese first quasi-axisymmetric stellarator (CFQS), modular coil, misalignment, effective helical ripple

DOI: 10.1585/pfr.14.3403151


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