volume | PIER Journals

Abstract

This paper presents a simple mathematical model to determine the force, stiffness and moment parameters in Permanent Magnet (PM) bearings made of radial magnetized ring magnets using Coulombian model and vector approach for five degrees of freedom. MATLAB codes are written to evaluate the bearing characteristics for three translational (x, y and z) and two angular (ξ and γ) degrees of freedom of the rotor magnet. The results of the mathematical model are compared with the results of Finite Element Analysis (FEA) using ANSYS and experiments for a PM bearing with one ring pair, thereby the presented mathematical model is validated. Furthermore, the PM bearing with three ring pairs with alternate radial polarizations are analysed by extending the presented mathematical model and also using ANSYS. Finally, the 5×5 stiffness matrix consisting of principal and cross coupled values is presented for the elementary structure as well as for the stacked structure with three ring pairs.

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Dr. Siddappa Iranna Bekinal

Dr. Anil Tumkur Ramakrishna

Dr. Soumendu Jana