In this work, non-uniform magnetization of magnetic rings of the thrust bearings constructed from permanent magnets are experimentally measured and analysed. Effects of the non-uniform magnetization and the soft-magnetic material on magnetic force of the thrust bearings are investigated using the theory of magnetic charges, and a model for predicting magnetic force of the thrust bearings is established. The model is verified experimentally. From this model, the magnetic force fluctuations caused by the non-uniform magnetization are calculated and analysed.
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