The advent of modern rare-earth permanent magnets, which have a magnetic energy product up to an order of magnitude greater than those of Alnico and ferrite magnets, with high remanence and coercive force, has resulted in improved performance of many devices and products. Modern rare-earth magnets, especially neodymium-iron-boron, when combined with technological advances in power and control e...

This paper presents the design, analysis and development of permanent magnet (PM) torque couplers. These couplers employ rare-earth magnets. Based on finite element analysis and earlier analytical works both concentric and face-type synchronous type couplers have been designed and fabricated. The experimental performance has good correlation with finite element calculations. Keywords—Finite Ele...

An analytical expression is derived for the magnetic field of a two-dimensional periodic circular array of head-to-head permanent magnets, assuming there is either no gap between the magnets or that they are separated by a non-magnetic pole-piece. Some more general symmetry properties are described. The force experienced by the magnets is calculated and an analytical approximation is derived. W...