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Magnetic Energy of Surface Currents on a Torus

By Hanno Essén, Johan Sten, and Arne B. Nordmark
Progress In Electromagnetics Research B, Vol. 46, 357-378, 2013


The magnetic energy and inductance of current distributions on the surface of a torus are considered. Specifically, we investigate the in°uence of the aspect ratio of the torus, and of the pitch angle for helical current densities, on the energy. We show that, for a fixed surface area of the torus, the energy experiences a minimum for a certain pitch angle. New analytical relationships are presented as well as a review of results scattered in the literature. Results for the ideally conducting torus, as well as for thin rings are given.


Hanno Essén, Johan Sten, and Arne B. Nordmark, "Magnetic Energy of Surface Currents on a Torus," Progress In Electromagnetics Research B, Vol. 46, 357-378, 2013.


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