Efficient Computation of Stellarator Coils with an Augmented Lagrangian Optimization Method

Abstract

Finding feasible coils for stellarator fusion devices is a critical challenge of realizing this concept for future power plants. Current design efforts struggle to navigate the highly nonconvex optimization landscape, spend considerable resources scanning the parameter space, and may produce suboptimal coils. In this work, we present an augmented Lagrangian approach to tackle the ill-posed problem of coil optimization. We illustrate its effectiveness and versatility by generating coils for five stellarators with very different symmetries and magnetic field shaping. In all cases, we find Pareto-optimal coil solutions that in various ways outperform published coil sets.

12 pages, 12 Figures

References in corpus (14)

• Magnetic fields with precise quasisymmetry for plasma confinement
• An improved current potential method for fast computation of stellarator coil shapes
• New method to design stellarator coils without the winding surface
• Omnigenity as generalized quasisymmetry
• Constructing precisely quasi-isodynamic magnetic fields
• Mapping the space of quasisymmetric stellarators using optimized near-axis expansion
• Symplectic integration with non-canonical quadrature for guiding-center orbits in magnetic confinement devices
• Single-stage gradient-based stellarator coil design: stochastic optimization
• Direct stellarator coil design using global optimization: application to a comprehensive exploration of quasi-axisymmetric devices
• Magnetic Fields with General Omnigenity
• Minimization of magnetic forces on Stellarator coils
• Stellarator Optimization with Constraints
• Exploration of the parameter space of quasisymmetric stellarator vacuum fields through adjoint optimisation
• Including the vacuum energy in stellarator coil design