中文摘要：

为研究尺寸效应对轴向磁化永磁电机性能的影响，采用有限元方法对双转子电机的磁场进行了仿真计算，得出了轴向磁化永磁电机转子的气隙磁密波形分布。分析了转子外形尺寸、充磁极数、磁体厚度和气隙长度对气隙磁密的影响，即随着气隙长度的增加，充磁极数多的转子产生的气隙磁密幅值的减小幅度大于充磁极数少的；随着磁体厚度的增加，气隙磁密为一上升曲线，当磁体厚度达到某一点时，气隙磁密幅值基本为一常数；减小转子直径时，随着磁体厚度的降低，平均半径处气隙磁密幅值的减小幅度越来越不明显，但为不使气隙磁密波形变形严重，永磁转子径向长度需至少大于1．5mm。分析结果可对该类电机微小型化过程中的设计起指导作用。

英文摘要：

In order to study the impact on its performance of the size effect in designing axial -magnetized permanent magnet micromotor, the finite element method was adopted to simulate the magnetic field of this kind of dual rotor motor, and the flux density wave form in the airgap was distributed. Different influences on the flux density was analyzed, which were the external dimensions, pole numbers and magnet thicknesses of the rotor and the airgap distances. With the increasing of the airgap distance, the flux density under more poles reduced more quickly than under fewer poles. With the increasing of the magnet thickness, the flux density was a rising curve, and after the magnet thickness got to a certain point, it was almost a constant. While reducing the diameter of the rotor, the decreasing of the flux density was slower and slower with the reducing of the magnet thickness. At the same time, the radial length of the rotor must be larger than 1.5 mm in order to avoid the seriously distorted waveform. The results of the analysis can guide the design of the microminiaturization of the motor.