Designing stellarators using perpendicular permanent magnets
arXiv:1912.05144 · doi:10.1088/1741-4326/ab9006
Abstract
We have developed a fast method to design perpendicular permanent magnets for simplifying stellarator coils based on existing codes. Coil complexity is one of the main challenges for stellarators. To date, only electromagnetic coils have been used to generate 3D fields for stellarators. Permanent magnets provide an alternative way to produce the desired magnetic field for optimized stellarators. In this paper, we revisit the concept of representing surface current using magnetic dipoles and carry out numerical validations. A surface magnetization is proven to be equivalent to the surface current that can be linearly solved by existing coil design codes. An incremental multi-layer method has been developed to obtain a practical solution that is attainable with present permanent magnets. With this method, we can reproduce a half-Tesla NCSX configuration using specially designed neodymium magnets together with simple planar coils. It shows that stellarator coils could be substantially simplified by adopting permanent magnets.
Accepted by Nuclear Fusion (https://doi.org/10.1088/1741-4326/ab9006)
References in corpus (5)
- An improved current potential method for fast computation of stellarator coil shapes
- New method to design stellarator coils without the winding surface
- Stellarators with permanent magnets
- An adjoint method for gradient-based optimization of stellarator coil shapes
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Cited by in corpus (11)
- Permanent magnet optimization for stellarators as sparse regression
- Calculation of permanent magnet arrangements for stellarators: A linear least-squares method
- Greedy permanent magnet optimization
- Design of an arrangement of cubic magnets for a quasi-axisymmetric stellarator experiment
- An Introduction to Stellarators: From magnetic fields to symmetries and optimization
- Improved stellarator permanent magnet designs through combined discrete and continuous optimizations
- Existence of an optimized stellarator with simple coils
- Computing the shape gradient of stellarator coil complexity with respect to the plasma boundary
- A framework for discrete optimization of stellarator coils
- Topology optimization of permanent magnets for stellarators
- Permanent magnet optimization of stellarators with coupling from finite permeability and demagnetization effects