混合磁轴承磁场与磁力解析计算

Analytical Calculation of Magnetic Field and Force for Hybrid Magnetic Bearing

为克服传统线性近似法的不足,采用积分法计算一种新型混合磁轴承的气隙磁阻,在此基础上得到气隙磁场分布及转子所受磁力的解析解,并将计算结果与线性近似法计算结果进行比较。将上述两种方法对气隙磁场分布的计算结果与有限元计算结果进行对比,结果表明积分法计算结果与有限元计算结果非常吻合,而线性近似法误差较大。线性近似法计算气隙磁阻和磁力的误差大小与转子位移大小和方向有关,尽管磁阻误差较小,但磁力误差在12%以上。积分法可以有效提高气隙磁阻、磁场分布和磁力的计算精度,为磁轴承分析与设计提供有力依据。

To overcome the drawbacks of the conventional linear approximation method,the air gap reluctance,magnetic field distribution and magnetic force on the rotor of a new hybrid magnetic bearing are calculated with the integral method,and the calculated results of the two methods are compared with each other.The magnetic field distributions calculated by the above two methods are compared with those calculated by the finite element method.It shows that the results calculated by the integral and finite element methods are in good agreement with each other,but the error in linear approximation computation is large.The errors of the air gap reluctances and magnetic forces in linear approximation computation are related to the magnitude and direction of the rotor displacement.Although the errors of air gap reluctances are small,those of magnetic forces are no less than 12%.The integral method can efficiently improve the calculation accuracy of the air gap reluctance,magnetic field distribution and magnetic force,and are particularly helpful for the analysis and design of magnetic bearing.