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Optimization of finite-build stellarator coils

Published online by Cambridge University Press:  20 August 2020

Luquant Singh*
Affiliation:
HSX Laboratory, University of Wisconsin, Madison, WI53706, USA
T. G. Kruger
Affiliation:
HSX Laboratory, University of Wisconsin, Madison, WI53706, USA
A. Bader
Affiliation:
HSX Laboratory, University of Wisconsin, Madison, WI53706, USA
C. Zhu
Affiliation:
Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ08540, USA
S. R. Hudson
Affiliation:
Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ08540, USA
D. T. Anderson
Affiliation:
HSX Laboratory, University of Wisconsin, Madison, WI53706, USA
*
Email address for correspondence: lsingh2@wisc.edu

Abstract

Finding coil sets with desirable physics and engineering properties is a crucial step in the design of modern stellarator devices. Existing stellarator coil optimization codes ultimately produce zero-thickness filament coils. However, stellarator coils have finite depth and thickness, which can make the single-filament model a poor approximation, particularly when coil build dimensions are relatively large compared to the coil–plasma distance. In this paper, we present a new method for designing coils with finite builds and present a mechanism to optimize the orientation of the winding pack. We approximate finite-build coils with a multi-filament model. A numerical implementation has been developed, and applications to the Helically Symmetric eXperiment stellarator and a new UW-Madison quasihelically symmetric configuration are shown.

Type
Research Article
Copyright
Copyright © The Author(s), 2020. Published by Cambridge University Press

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References

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