水轮发电机组机械故障的电气信号特征分析

Analysis of Electrical Signal Characteristics of Mechanical Failure of Hydro-generator Sets

水轮发电机组在运行中,因为转子匝间短路、转子不对称加热等故障导致机组出现异常振动,轻则影响发电质量,严重时还会导致发电机停运。通过收集并分析发电机组机械故障的电气信号,进而判断引起故障的原因、发生故障的位置,为技术人员进行故障诊断与维修提供依据。本文首先分析了引起水轮发电机组转子异常振动的常见原因,随后从垂直振动量、水平振动量、空载电压电气量等方面,对转子振动故障的电气信号特征展开了分析。并通过不同频率下电气量频谱特征对比,表明了转子不平衡电气特征幅值随转频增加而变大,验证了基于空载电压进行电气量故障诊断是切实可行的。

During the operation of the hydro-generator unit,abnormal vibration of the unit occurs due to the short-circuit between turns of the rotor and asymmetric heating of the rotor,which affects the quality of power generation at light level,and even causes the generator to shut down in severe cases.By collecting and analyzing the electrical signals of the mechanical failure of the generator set,it can then determine the cause of the failure and the location of the failure,so as to provide the basis for the technicians to diagnose and repair the failure.This paper firstly analyzes the common causes of abnormal vibration of the rotor of hydro-generating units,and then analyzes the electrical signal characteristics of rotor vibration faults from the aspects of vertical vibration,horizontal vibration,and no-load voltage electrical quantity.And through the comparison of the spectral characteristics of electrical quantities at different frequencies,it is shown that the amplitude of the electrical characteristics of the unbalanced rotor increases with the increase of the rotating frequency,which verifies that the electrical quantity fault diagnosis based on the no-load voltage is feasible.