Abstract:

Permanent magnet thrust bearings featured high rotational speed， low noise， and frictionless operations， but suffered from low load carrying capacity and non-universal structures. Aiming at these problems， a modular multi-cellular element structure of permanent magnet thrust bearings was proposed， where four permanent magnets formed a single cell element. By adjusting the number and arrangement of cell elements， various nested and crossover configurations were realized. Based on the finite element software， the bearings with two-layer nested two-pole crossover， four-layer nested four- pole crossover， six-layer nested six- pole crossover and eight-layer nested eight-pole crossover were constructed with a total of four structures， and the load carrying performances of the different structures were analyzed. The simulation results show that the bearing capacity first increases and then decreases with the increase of axial displacements， and the maximum axial bearing capacity of the permanent magnet thrust bearings of the four configurations was as 6.78，50.52，136.85，288.9 kN. Finally， a four-layer nested four-pole-crossed permanent magnet thrust bearing prototype was fabricated and the axial bearing capacity experimental validation was carried out， and the results show that the maximum load capacity of the experiments is 4.2% lower than the simulation value.

Key words: permanent magnet bearing, multi-cellular element, structural design, carrying characteristics

摘要：

永磁推力轴承具有转速高、噪声小和无摩擦等优势，但承载能力较低，同时现有的结构不具有通用性。提出了一种模块化多胞元结构的永磁推力轴承，以4块永磁体为一个胞元，通过改变胞元的数量和排列方式实现了多种嵌套和交叉结构的轴承。基于有限元软件构建了两层嵌套两极交叉、四层嵌套四级交叉、六层嵌套六级交叉和八层嵌套八极交叉共4种结构的轴承，分析了不同结构的承载性能。仿真结果表明，轴承的承载力随着轴向位移的增大先增大后减小，4种结构的永磁推力轴承最大轴向承载力分别为6.78、50.52、136.85、288.9 kN。最后制作了四层嵌套四极交叉的永磁推力轴承实验样机，并进行了轴向承载力实验验证，结果表明实验的最大承载比仿真值小4.2%。

关键词: 永磁轴承, 多胞元, 结构设计, 承载特性