学术论文

      一种电机振动不稳定现象诊断和治理

      Diagnosis and Treatment of an Unstable Motor Vibration Case

      摘要:
      介绍了电机安装调试中振动逐渐增大至超标,调整合格后运行一段时间又超标,且如此反复的不稳定情况.通过对振动的波形图分析得出原因是支架加工工艺不当,应力持续释放导致激振力增加、刚度变小、动力放大系数增加.提出“工艺改善-结构优化-数值模拟”三位一体的改造方法.选择改用高温回火,提高加工标准,消除应力释放和安装误差对振动产生不稳定影响.对支架结构优化,并建立有限模型计算“电机-支架”固有频率,以确保远离共振区,从而降低放大系数对刚度的敏感度.改造后振动稳定,最大值为0.6 mm/s,结果表明原因分析基本正确,有限元模型准确,“工艺改善-结构优化-数值模拟”三位一体的改造方法和相应具体措施有效.
      Abstract:
      The unstable motor vibration beyond the related standard which has happened repeatedly after adjustments during installation and commissioning is presented.The analysis on the waveforms concludes that it is due to the improper processing technique of the support,the increasing exciting force caused by the continuous stress releasing,the decrease of stiffness and the enhancement of dynamic amplification factor.Then,a modification plan of combining technique improvement,structure optimization and numerical simulation is proposed,which includes high-temperature tempering and strict processing standards to reduce the effects of stress release and installation deviation on the vibration.In addition,the support structure is optimized through calculating the nature frequencies of the motor-support system based on the finite element modeling to ensure that they keep certain distance from the resonance ranges and reduce the sensitivity of the amplification factor over stiffness.After the modification,the vibration keeps stable with the maximum amplitude of 0.6 mm/s.The modification results show that the cause analysis is basically correct and the finite element model is accurate.The trinity modification plan and the corresponding physical measures are effective for the excessive and unstable vibration treatment.
      作者: 李振 [1] 胡大千 [2]
      Author: LI Zhen [1] HU Daqian [2]
      作者单位: 福建福清核电有限公司,福建福清,350318 上海电力股份上海上电电力工程有限公司,上海,200090
      刊 名: 中国电力 ISTICPKU
      Journal: Electric Power
      年,卷(期): 2017, 50(3)
      分类号: TM623 TB53
      在线出版日期: 2017年4月6日