一种新型磁悬浮飞轮用永磁偏置径向磁轴承

针对现有径向磁轴承结构电励磁磁路耦合严重的缺点，分析了一种新型磁悬浮飞轮用永磁偏置径向磁轴承结构及其工作原理。采用等效磁路法对磁轴承的永磁磁路和电励磁磁路进行计算，得出了磁轴承的数学模型，给出了磁轴承主要参数的设计方法。最后通过有限元法对该磁轴承进行仿真分析，从磁场分布以及X方向通电流时对力Fy的影响两方面验证该结构电励磁回路在X、Y方向间的解耦性，其中Fy小于3%Fx。理论研究和仿真分析表明：这种径向磁轴承结构有效的避免了磁通在两个径向自由度间的耦合，从而能够扩大系统线性工作范围和稳定裕度最终提高磁轴承系统的控制性能。

A Novel permanent magnetic bias radial magnetic bearing in magnetically suspended flywheel application

According to the defects of the present radial hybrid magnetic bearing, the configuration and fundamental principle of a novel permanent magnetic bias radial magnetic bearing are introduced in this paper. The flux path was analyzed by using equivalent magnetic circuit, and the mathematics models of magnetic bearing were deduced. The parameter’s design method was also presented. Finally, the radial magnetic bearing was simulated and calculated by using FEM so as to check the decoupling characteristic of the excitation magnetic flux between X and Y direction through two methods, one was magnetic field distribution and the other was the influence to force Fy while plus current ix in X direction’s coils. The influence was testified very little that the force Fy was less than 3% of the force Fx which almost can ignored. The theoretic analysis and simulation have shown that this novel radial magnetic bearing can avoid the coupling between X and Y direction effectively compared to the existing structure. As a result, the control will be more easier and the performance can also be improved.