水电站发电机运行异常噪声成因分析

Analysis of Abnormal Operation Noise of a Hydropower Generator

峡阳水电站3号发电机在2019年11月运行过程中出现异常噪声,考虑到机组的安全稳定运行,对其产生原因展开相关研究。通过现场对定转子之间的间隙进行测量发现间隙变小,且定转子圆度不佳,同时分析历史数据也发现转子上下游侧圆度分布不均,进而判断转子存在一定变形。根据有限元分析,转子刚强度满足设计要求;对转子进行了模态分析,得出转子第8阶振型与2020年3月车间转子圆度测量数据分布图保持一致,因此判断发电机运行过程中由于转子振动导致机组产生噪声,同时根据分析结果提出了相关改造建议。

Abnormal noise is observed during the operation of the No.3 generator in Xiayang Hydropower Station in November 2019.To ensure its safe and stable operation,possible causes of this problem are analyzed.On-site measurement of the clearance between the rotor and the stator shows that the clearance becomes smaller and the roundness of the stator and rotor is not good.Analysis of historical data also shows that the roundness of the rotor along the upstream and downstream sides is not evenly distributed.It is concluded that the rotor is of certain deformation.Then,finite element analysis shows that the rigidity and strength of the rotor fulfill the design requirements.Modal analysis shows that the 8 th vibration mode of the rotor is consistent with the distribution diagram of the roundness measurement data in March 2020.Thus,it is judged that the operation noise of the generator is caused by the rotor vibration.Corresponding renovation suggestions are also proposed based on the analysis results.