Design and Analysis of Homopolar Electrodynamic Bearing with Radial Magnets

The demand for low-loss and low-cost magnetic bearings is high. Currently, prevailed reliable solutions for the magnetically supported rotor are active or partially passive (hybrid) electromagnetic bearings. Nevertheless, those solutions require power electronics to supply the current into coils that create electromagnetic forces acting on the rotor. On the other hand, electrodynamic bearing works on the principle of electrical induction of eddy currents in the conductor. As can be deduced, the supporting forces are generated only if the change in the magnetic field is present.In this paper radial homopolar electrodynamic magnetic bearing is analysed. The advantage of homopolar electrodynamic bearing is in low-loss operation due to fact that currents in the conductor are induced only if the rotor is off-centred. Quasi radial magnetisation has been provided by a pair of opposing axial magnets. With the use of radial magnets in various arrangements instead, electrodynamic bearing reaches promising parameters in sense of stiffness and damping.