Analysis of a combined radial-axial magnetic bearing for a high-speed drive system

High-speed and high-power-density drives are attracting much interest in today's industry, e.g. for applications with mesoscale gas turbine generator systems or turbocompressors for fuel cells. In all high-speed machinery the bearing is a key component. Therefore, this paper presents the analysis of an active magnetic bearing suitable for a permanent magnet machine, being part of a high-speed electrical drive system. The focus is on the detailed analysis of the magnetic forces, the coupling between the different axes and the verification of the theoretical considerations by means of 3D-FEM simulations. The analysis of the bearing forces is needed to implement the position control to the prototype of the bearing system, which already has been built.