磁通方向变化对电磁轴承径向耦合动特性的影响

电磁轴承轴颈径向的微小扰动Δx或Δy除了影响轴承气隙长度外,同时还会影响轴承的磁通方向,此时,如果仅考虑轴承气隙变化,电磁轴承径向不会产生耦合;如果进一步考虑轴承磁通方向的变化,将会改变轴承磁力在径向的分配,从而导致轴承产生径向耦合。本文首先分析了轴颈径向扰动对电磁轴承磁通方向的影响,然后,在同时考虑气隙和磁通方向变化的基础上建立了电磁轴承径向刚度的计算模型,最后给出了轴承磁极耦合刚度的数值计算结果,并进行了相应的分析。

Effect of Flux Direction Change on Radial Coupling Dynamic Characteristics of Magnetic Bearings

Both the air gap length and magnetic flux direction of an electro-magnetic bearing are affected by the micro-perturbation of its shaft neck. If we consider only the change of air gap length, the coupling in the radial direction of the bearing will not occur. But if the change of its magnetic flux direction is taken into account, the magnetic force distribution in the radial direction will change and bring about its radial coupling. In this paper, we analyze the effect of the radial perturbation of the shaft neck on the magnetic flux direction. Then we establish the calculation model with the changes of both the air gap and magnetic flux direction taken into consideration. Finally we give the numerical calculation results and their analysis for the coupling stiffness of the magnetic poles of the bearing.