电机整机结构振动模态试验与参数识别研究

Research on Vibration Modal Experiment and Parameters Identification of Motor Whole-machine

为提高电机运行的稳定性,降低振动噪声对其使用性能和寿命的影响,利用随机子空间模态识别方法对某型号电动机整机进行了模态分析。详细阐述了随机子空间模态识别法的数学原理,采用锤击法完成电机整机的模态测试,进一步识别出电机的四阶模态参数,固有频率、阻尼比及振型,根据分析结果找出电机的风扇罩和定子外壳中间位置为结构的薄弱环节,进而提出了相应的改进设计方法与减振措施。分析结果表明随机子空间法可用于电机整机结构的模态参数识别,分析结果为电机的结构动力修改与优化设计提供了参考数据。

To improve the operation stability of electric motor and reduce the impact of vibration and noise on its performance and life,the modal analysis based on stochastic subspace modal identification of a certain type of motor was performed.Firstly,the mathematical principle of Stochastic subspace identification was explained in detail.Secondly,the modal test of the whole motor structure was completed using the hammer method,and then four orders natural frequency,damping ratio and mode shape were identified.Finally,the weak points of the structure were found in the middle of the fan cover and the stator housing of the motor from the modal experiment result analysis,and corresponding designed approaches and measure of vibration mitigation.The example analysis shows that the Stochastic subspace identification method can be used to identify the modal parameters of the motor whole-machine structure,and the analysis results provide a reference date for the electric motor optimization design.