准确分析定子固有模态对低振动噪声电机系统优化设计和控制有十分重要的意义。针对大型分体式磁轴承电动机系统,采用有限元仿真方法分析轴向磁轴承定子绕组、径向磁轴承定子叠片结构、机座螺栓连接以及底座附加质量对大型分体式磁轴承电动机系统定子模态的影响。结果表明:轴向轴承定子绕组对定子固有频率影响较大,宜采用质量计入铁心的方式处理;径向轴承定子叠片结构对定子固有频率的影响较小,可按各向同性处理;机座螺栓连接刚度对机座固有频率有一定影响,但当连接刚度远大于机座刚度时,影响较小;底座附加质量对整机模态频率有一定的影响,但对不同振型的固有频率的影响效果相差较大。计算了整机的模态频率,并与振动试验结果进行了对比验证。
Accurate analysis of the stator modal shapes and natural frequencies is very important for reducing acoustic noise and vibration of electrical machine. The stator mode of motor based on large distributedmagnetic bearings(MB) is studied by finite element method(FEM). Effects of axial MB windings, radial MB laminations, mounting feet, and additional mass on stator natural frequencies are investigated. The results show that:Stator windings have great effects on natural frequencies of axial MB, and those are suitable dealt with mass into stator cores. Less impact of stator laminations on the natural frequencies of radial MB, those can be dealt as isotropic structure. Bolt joint has some influence on natural frequencies of stator. But when the connection is much greater than the shell stiffness, the connection stiffness has little effect on natural frequencies. Additional mass can make difference to natural frequencies, and the effects of the frequencies vary with different modal shapes. The calculation results of machine’s 12 modes are validated against experimental results.