paper 150115033746

Published: 2015-07-09

A Short Note on the Optimization of Halbach Arrays Used as Magnetic Springs

Daniel Mansson

Royal Institute of Technology (KTH), Sweden

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Proceedings of 2015 Photonics & Electromagnetics Research Symposium, Prague, July 6 - 9，Page(s)1328-1332

Abstract

Modern neodymium magnets are today widely used for a wide variety of purposes and some commercial types have an adhesive force of approximately 100 kg even though the dimensions are only 5 ∗ 5 ∗ 2.5 cm. Therefore the idea of using permanent magnets as springs isn’t uncommon. Here, the specific magnetization scheme often described as a “Halbach array” is analyzed in the use as elements of a magnetic spring. The Halbach array has (ideally) a one sided flux and here both analytical methods using Maxwell’s stress tensor and numerical simulations using FEMM are applied to calculate the restorative force created for two such opposing magnetic structures. This vertical force is highly dependent upon the dimensions of the structures and the magnetization wavelengths in the materials. Thus, varying these parameters will greatly affect the characteristics of the magnetic spring (e.g., spring stiffness, maximum restorative force etc.). Different applications will require different physical dimensions and magnetization wavelengths in the material.

Citation

Daniel Mansson, "A Short Note on the Optimization of Halbach Arrays Used as Magnetic Springs," Proceedings of 2015 Photonics & Electromagnetics Research Symposium, Prague, July 6 - 9，Page(s)1328-1332

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