Comparison of Rotor Magnetic Circuit Topologies for Passively Levitated Self-bearing Machines

Self-bearing motors can reach high rotation speeds thanks to the rotor magnetic levitation. In order to improve the compactness of such a motor, a fully passive levitation achieved with an electrodynamic thrust bearing has recently been proposed and studied. However, the proposed topologies do not integrate magnetic circuit in the rotor, or only at a significant distance from the winding, although it can improve the performance of the motor and the suspension through the impact it can have on the inductance coefficients of the winding. In this context, this paper aims to compare different rotor magnetic circuits topologies on the performance of axial flux self-bearing motors based on electrodynamic suspensions.