小波分析在汽轮机振动故障诊断中的应用研究

针对常见的汽轮发电机组频率突变的振动故障,采用傅立叶变换和小波变换对同一汽轮发电机组振动信号进行傅立叶变换和小波分解。结果表明傅立叶变换无法检测出信号的瞬态变化,只适用于分析平稳信号;而小波分析可以有效的提取信号的瞬态变化特征,能准确的检测出信号的奇异点位置,利用小波分析有利于提取汽轮发电机组振动信号的故障特征。此外,对汽轮发电机组的混合信号进行小波分解,可以将信号有效的分离,为确定故障种类提供了依据。

Application Study of Wavelet Analysis in Steam Turbine Vibration Fault Diagnosis

In view of the common frequency mutation vi- bration fault of the steam turbine generator unit, Fourier trans- form and wavelet transform are carried out on the vibration signals of the same steam turbine generator unit. Transform results show that Fourier transform can＇t detect the transient change of the signals and it is only suitable for stationary signal analysis. The results also show that the wavelet analysis can effectively extract the transient change characteristics of the signals, which can accurately detect the singularity position of the signal. Therefore, the wavelet analysis may be used to extract fault fea- tures of the steam turbine generator unit vibration signals. In ad- dition, wavelet analysis is implemented to the mixture signals of the steam turbine generator unit, which may separate the signals effectively, providing the basis for determining fault types.