发电机组橡胶柱销联轴器异常振动噪声诊断

Abnormal Vibration Noise Diagnosis for Rubber Pin Coupling of Diesel Generating Set

为诊断某型柴油发电机组产生的异常噪声故障,将经验模态分解方法(empirical mode decomposition,简称EMD)和Hilbert变换用于发电机主轴承的非平稳振动信号处理,有效提取了主轴承振动信号的时频特征,对机组振动噪声信号、发电机主轴承振动和轴系扭振信号进行了分析。诊断结果表明,由于柴油机激励下机组轴系扭振幅值过大,引起柱销联轴器橡胶件表面的相对运动,产生干摩擦作用力,导致机组轴系产生间歇性的异常振动噪声。该方法对旋转轴系部件摩擦引起的振动噪声故障诊断具有参考价值。

In order to diagnose the abnormal noise of a certain type of diesel generating set,a new method of empirical mode decomposition(EMD)and Hilbert transform is proposed to analyze the non-stationary vibration signals of the generator main bearing,which can effectively extract the time-frequency characteristics of main bearing vibration signals.Comprehensive analyses are made based on the signals of diesel generating set noise,generator main bearing vibration and shaft system torsional vibration.The diagnostic results show that the torsional vibration amplitude values of the shaft system are too high,with diesel engine excitation causing the relative motion of pin coupling rubber parts surfaces.This procedure can produce dry friction force,which leads to the intermittent abnormal vibration noise of the shaft system.This method has reference value for the abnormal vibration noise diagnosis caused by friction of the rotary shaft system components.