Interaction Between Ring-Shaped Permanent Magnets With Symbolic Gradients: Application to Magnetic Bearing System Optimization

Permanent magnets and hard magnetic materials

This review deals with the definition and development of hard magnetic materials with special emphasis on more recent developments in this field. After discussing the fundamental properties of all hard magnetic materials, based on the intrinsic and extrinsic properties, some remarks on the history of hard magnetic materials and permanent magnets are given. The important hard ferrites are only b...

Magnetic reversal in Sm2Fe17Ny permanent magnets

Axial Flux Interior Permanent Magnet Synchronous Motor with Sinusoidally Shaped Magnets

A new permanent magnet design for axial flux interior permanent magnet (AFIPM) motor is described in this paper. Poleshoes are traditionally used to produce sinusoidal flux linkage and sinusoidal EMF especially in the case of radial flux synchronous machines. Poleshoes are not a practical solution in the case of axial flux PM machine. The use of poleshoes in the production of sinusoidal back EM...

Fabricating Unidirectional Magnetic Papers Using Permanent Magnets to Align Magnetic Nanoparticle Covered Natural Cellulose Fibers

This paper reports a simple innovative method to align magnetic cellulose fibers by using a simple permanent magnet to fabricate unidirectional magnetic papers. Magnetic cellulose fibers were made by in situ synthesis of magnetite nanoparticles on alpha cellulose pulp extracted from American southern pine. Scanning electron microscope micrographs and energy dispersive X-ray spectroscopy maps in...

Alternative method to calculate the magnetic field of permanent magnets with azimuthal symmetry

The magnetic field of a permanent magnet is calculated analytically for different geometries. The cases of a sphere, cone, cylinder, ring and rectangular prism are studied. The calculation on the axis of symmetry is presented in every case. For magnets with cylindrical symmetry, we propose an approach based on an expansion in Legendre polynomials to obtain the field at points off the axis. The ...