# 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…

## 9 Citations

### Single-stage gradient-based stellarator coil design: Optimization for near-axis quasi-symmetry

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### The DESC Stellarator Code Suite Part II: Perturbation and continuation methods

- PhysicsArXiv
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A new perturbation and continuation method is pre-sented for computing and analyzing stellarator equilibria. The method is formally derived from a series expansion about the equilibrium condition F ≡…

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### Bayesian maximum a posteriori‐estimation of κ turbulence model parameters using algorithmic differentiation in SOLPS‐ITER

- Computer ScienceContributions to Plasma Physics
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This paper applies algorithmic differentiation (AD) as an efficient and more accurate alternative for gradient calculation in large, continuously developed codes as SOLPS‐ITER, using gradient‐based optimization with gradients obtained through tangent AD to find the maximum a posteriori (MAP) values of the parameters.

### Gradients are Not All You Need

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This short report discusses a common chaos based failure mode which appears in a variety of differentiable circumstances, ranging from recurrent neural networks and numerical physics simulation to training learned optimizers.

### Computation of the Biot–Savart line integral with higher-order convergence using straight segments

- Physics
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One common approach to computing the magnetic field produced by a filamentary current-carrying coil is to approximate the coil as a series of straight segments. The BiotSavart field from each…

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