Geometric concepts for stellarator permanent magnet arrays

Abstract

The development of stellarators that use permanent magnet arrays to shape their confining magnetic fields has been a topic of recent interest, but the requirements for how such magnets must be shaped, manufactured, and assembled remain to be determined. To address these open questions, we have performed a study of geometric concepts for magnet arrays with the aid of the newly developed MAGPIE code. A proposed experiment similar to the National Compact Stellarator Experiment (NCSX) is used as a test case. Two classes of magnet geometry are explored: curved bricks that conform to a regular grid in cylindrical coordinates, and hexahedra that conform to the toroidal plasma geometry. In addition, we test constraints on the magnet polarization. While magnet configurations constrained to be polarized normally to a toroidal surface around the plasma are unable to meet the required magnetic field parameters when subject to physical limitations on the strength of present-day magnets, configurations with unconstrained polarizations are shown to satisfy the physics requirements for a targeted plasma.

arXiv comment21 pages, 17 figures

References in corpus (2)

• An improved current potential method for fast computation of stellarator coil shapes
• Stellarators with permanent magnets

Cited by in corpus (5)

• Permanent magnet optimization for stellarators as sparse regression
• Calculation of permanent magnet arrangements for stellarators: A linear least-squares method
• Design of an arrangement of cubic magnets for a quasi-axisymmetric stellarator experiment
• Improved stellarator permanent magnet designs through combined discrete and continuous optimizations
• Permanent magnet optimization of stellarators with coupling from finite permeability and demagnetization effects