Determination of forces and linearized parameters of radial active magnetic bearings by finite element technique

Load capacity is a primary performance criterion of an active magnetic bearing (AMB) system. The load capacity depends on the size and geometry of the bearings as well as on the performance of the control system. In this paper, we use a nonlinear two-dimensional (2-D) finite element method (FEM) to predict the performance of radial magnetic bearings. The force calculations based on the finite element method are verified by measurements with two machines equipped with active magnetic bearings. The parameters of a linearized model of radial bearings are also calculated at different operation points. With this information, the load capacity can be estimated.