Plasma and Fusion Research

Volume 13, 3405067 (2018)

Regular Articles

Magnetic Configuration and Modular Coil Design for the Chinese First Quasi-Axisymmetric Stellarator
Haifeng LIU1,4), Akihiro SHIMIZU2), Mitsutaka ISOBE2,3), Shoichi OKAMURA2), Shin NISHIMURA2), Chihiro SUZUKI2), Yuhong XU1), Xin ZHANG1), Bing LIU1), Jie HUANG1), Xianqu WANG1), Hai LIU1), Changjian TANG1,4), Dapeng YIN5), Yi WAN5) and CFQS team1,2)
Institute of Fusion Science, School of Physical Science and Technology, Southwest Jiaotong University, Chengdu 610031, China
National Institute for Fusion Science, National Institutes of Natural Sciences, Toki 509-5292, Japan
SOKENDAI (The Graduate University for Advanced Studies), Toki 509-5292, Japan
Physics Department, Sichuan University, Chengdu 610041, China
Hefei Keye Electro Physical Equipment Manufacturing Co., Ltd, Hefei 230000, China
(Received 28 December 2017 / Accepted 13 March 2018 / Published 12 June 2018)


The Chinese First Quasi-axisymmetric Stellarator (CFQS) is a joint project of international collaboration. It is designed and fabricated by Southwest Jiaotong University (SWJTU) in China and National Institute for Fusion Science (NIFS) in Japan. In this work, a plasma boundary and modular-coil system for the CFQS have been designed and optimized via scan of the magnetic configurations with various aspect ratios. The present target parameters of the CFQS are as follows: toroidal periodic number, aspect ratio, magnetic field strength and major radius are 2, 4.0, 1.0 T, and 1.0 m, respectively. The VMEC and NESCOIL codes are employed to obtain the optimum coil design via minimizing the normal component of the magnetic field on the target plasma boundary surface generated by the modular coils. In order to estimate the accuracy of the filament coils, the shape of the plasma boundary, rotational transform, depth of magnetic well and main Fourier components of magnetic field strength produced by the modular-coil system are compared with the target plasma boundary, rotational transform, depth of magnetic well and main Fourier components, correspondingly. This comparison between properties of the coil induced configuration and the target configuration shows a good agreement.


quasi-axisymmetric stellarator, modular coil, plasma boundary, configuration optimization

DOI: 10.1585/pfr.13.3405067


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