Study of Permanent Magnet Bearings and their Stiffness

Subject Areas : Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering

محمد اسماعیلی ادبی ¹ , شهربانو فرخنده ² , مجید رشیدی ³

1 - مربی، دانشگاه آزاد اسلامی، واحد شهرقدس، گروه فیزیک، تهران، ایران.
2 - کارشناسی ارشد، دانشکده مهندسی مکانیک، دانشگاه ایالتی اوهایو آمریکا.
3 - استادیار، دانشکده مهندسی مکانیک، دانشگاه ایالتی اوهایو آمریکا

Received: 2015-09-29 Accepted : 2015-09-29 Published : 2011-06-22

Keywords: Stiffness, Active magnetic bearing, Electrodynamic effects, Magnetic flux,

Abstract :

A typical passive magnetic bearing has been modeled and analyzed for its performance characteristics. The magnetic bearing studied in this work comprised of a Shaft, inner magnets sleeved over the shaft, and outer magnetic rings. A detailed analysis has been perform on the force exerted by a permanent magnet on the shaft nurture to restore the shaft to its equilibrium position when an eccentricity is induced between the magnet and the shaft . A relation between the force exerted and the displacement of the shaft from its equilibrium position has been developed hence determining a specific stiffness value.

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