Optimized finite-build stellarator coils using automatic differentiation

@article{McGreivy2020OptimizedFS,
  title={Optimized finite-build stellarator coils using automatic differentiation},
  author={Nick McGreivy and Stuart R. Hudson and C. Zhu},
  journal={Nuclear Fusion},
  year={2020},
  volume={61}
}
A new stellarator coil design code is introduced that optimizes the position and winding pack orientation of finite-build coils. The new code, called flexible optimized curves in space using automatic differentiation (AD) and finite build (FOCUSADD), performs gradient-based optimization in a high-dimensional, non-convex space. The derivatives with respect to parameters of finite-build coils are easily and efficiently computed using AD. FOCUSADD parametrizes coil positions in free space using a… 

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Optimization of finite-build stellarator coils

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