Non-Station Signal Analyse And Appliance Based On Multiple Modulation Zoom Spectrum Analysis

The improving the quality of fault detection of electric system depends on the accurate and real-time detection of dense spectrum.The mutiple modulation zoom spectrum method can slake this detect.When the mutiple modulation zoom spectrum method is implement,the interesting frequency band is moved to the zero by complex multiplication,a low pass filter is used to avoid the spec-trum leak,the filtered data is resample and get a short samples.By this way the mutiple modulation zoom spectrum method can get the high frequency resolution in the interesting frequency band and low frequency resolution in the other frequency band.This algorithm is simulated and analyzed,it is proved that it has be higher frequency resolution,better stability,anti-noise than traditional FFT.It is propitious to application of dense spectrum,and has employ value about analysis and diagnosis for online device.