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arXiv · 1907.01363

Stellarators with permanent magnets

P. Helander·M. Drevlak·M. Zarnstorff·S. C. Cowley
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Abstract

It is shown that the magnetic-field coils of a stellarator can, at least in principle, be substantially simplified by the use of permanent magnets. Such magnets cannot create toroidal magnetic flux but they can be used to shape the plasma and thus to create poloidal flux and rotational transform, thereby easing the requirements on the magnetic-field coils. As an example, a quasiaxisymmetric stellarator configuration is constructed with only 8 circular coils (all identical) and permanent magnets.

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P. Helander, M. Drevlak, M. Zarnstorff, S. C. Cowley. 2020-01-08. Stellarators with permanent magnets. https://doi.org/10.1103/physrevlett.124.095001

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