A Survey of Magnetic Levitation and Magnetic Bearing Types

Abstract

Magnetic levitation has been studied mainly in two distinct fields of application, MAGLEV transportation and rotor bearings. A unitied overview, as it is attempted in this paper, reveals that there are many radically different types of magnetic levitation. A systematic classification of these basic levitation principles is proposed. It starts from the fundamental manner to obtain the magnetic force. The systematization derived in this manner aims at including all possible basic magnetic levitation types. As a result some little known levitation types are inc1uded, among them Lorentz-force bearings and tuned LC bearings. As a special feature, a new type of active bearing is presented, the so-called self-sensing active bearing using no gap sensor. This remarkable bearing type combines high static load and low hardware costs. Examples of realizations are given.