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arXiv · 1705.02333

New method to design stellarator coils without the winding surface

Caoxiang Zhu·Stuart R. Hudson·Yuntao Song·Yuanxi Wan
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Abstract

Finding an easy-to-build coils set has been a critical issue for stellarator design for decades. Conventional approaches assume a toroidal "winding" surface. We'll investigate if the existence of winding surface unnecessarily constrains the optimization, and a new method to design coils for stellarators is presented. Each discrete coil is represented as an arbitrary, closed, one-dimensional curve embedded in three-dimensional space. A target function to be minimized that covers both physical requirements and engineering constraints is constructed. The derivatives of the target function are calculated analytically. A numerical code, named FOCUS, has been developed. Applications to a simple configuration, the W7-X, and LHD plasmas are presented.

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Caoxiang Zhu, Stuart R. Hudson, Yuntao Song, Yuanxi Wan. 2017-05-05. New method to design stellarator coils without the winding surface. https://doi.org/10.1088/1741-4326%2Faa8e0a

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