基于HHT和广义Fourier变换变频调速异步电动机故障诊断

Fault Diagnosis Way Based on HHT and Generalized Fourier Transform in Induction Motor Fed with Variable Frequency Power

在变频调速异步电动机的故障诊断过程中,由于电源频率的时变性,容易淹没故障特征信号.针对调速过程中常见的恒加速和恒减速运行模式,提出了采用HHT(Hilbert-Huang变换)方法识别运行模式、利用广义Fourier变换进行时频转换的故障诊断方法,可将线调频的电源信号转换为新的时频域的恒频信号.仿真表明该方法能达到突出故障特征的目的.

During the fault diagnosis process of the induction motor fed with variable frequency power,the fault related characteristic components are often submerged by the strong power supply due to the frequency of variability.According to the operation model of constant acceleration and constant deceleration in the speed regulation process,a fault diagnosis method is proposed for identifying the operation mode on the basis of Hilbert-Huang transformation method（HHT）and time-frequency transforming with the generalized Fourier transform,and the frequency signal of power line can convert to the constant frequency signal of the new time-frequency domain.Simulation shows that the method can highlight the fault features.