New Signal Processing for Extracting Fundamental Vibration Component of Rotor in Startup or Shut Down Process

For the traditional signal processing algorithms, it is difficult to process the complicated vibration signals of rotor in startup or shut down process due to the huge calculation task and poor ability to extract wide-band signals. Following zero-phase filter and phase demodulation principle, a novel method for extracting the fundamental vibration component of rotor is proposed. The wide-band fundamental vibration component can be demodulated into a narrow-band interval via once nonlinear phase demodulation, which is segregated with the band of other higher-order harmonics in frequency domain, then the fundamental component is extracted by a zero-phase filter. The simulation calculation and experimental validation demonstrate that the proposed method outperforms the traditional signal processing algorithms by its simple mechanism, quick calculation and little limit to the band between adjacent components. The visual selection of filtering parameters can be directly realized in frequency domain and the extracted amplitude and phase of the fundamental components are accurate for the further calculation and analysis. © 2018, Editorial Office of Journal of Xi'an Jiaotong University. All right reserved.