径向磁化的双筒永磁轴承轴向磁力研究

为了解决径向磁化的双筒永磁轴承轴向磁力数值计算复杂及缺乏计算轴向磁力的工程化解析模型等问题,该文在分析磁筒气隙磁导的基础上,结合磁通连续性原理和稀土永磁材料特性,通过电磁场理论中的虚位移法得到了该型轴承工程化轴向磁力解析数学模型。模型表明:该型轴承轴向磁力与磁筒剩磁的平方成正比;轴向磁力随磁筒间隙半径、轴向长度及磁路总磁导的增大而增大,随磁筒间隙的增大而减小。在轴承正常轴向工作范围内,该模型计算值与实验值相当吻合。

Study of the Axial Magnetic Force of Radial Magnetization Bi-barrel-shaped Permanent Magnetic Bearings(PMB)

The calculation of the axial magnetic force of radial magnetization bi-barrel-shaped PMB is very complex,and there is no practical analytical model for such calculation.To overcome this difficulty,we derive an analytical model of the axial magnetic force of radial magnetization bi-barrel-shaped PMB by the virtual displacement method in electromagnetism field theory.such a model is based on the analysis of the gap magnetic conductance of bi-barrel-shaped PMB,taking into consideration the principle of magnetic-flux equivalency and rare earth permanent material property.This model indicates that the axial magnetic force of radial magnetization bi-barrel-shaped PMB is proportional to the second power of residual magnetism induction density;and that the axial magnetic force increases with an increment in the gap radius and axial length of magnetic barrel as well as total magnetic conductance of magnetic circuit,and that the axial magnetic force decreases with an increment in the bi-barrel gap.The calculation results by this model are in agreement with those actually-measured in a normally axial movement space of PMB.