Modelling of non-linear magnetic bearings with the help of the finite-element method

This paper is concerned with the modelling of magnetic bearings without premagnetization. The strongly nonlinear relationship between magnetic force, displacement of the voter shaft, and regulating magnetomotive force should be modelled accurately. Based on art equivalent magnetic circuit, a model structure with an unknown parameter vector is established With the help of the finite-element method this parameter vector is determined by minimizing an error function which describes the difference between the real system and the model. The approach with the help of numerical analysing tools such as the finite-element method shows a general way of modelling a complex system.