REMOVAL METHOD OF ELECTROMAGNETIC VIBRATIONAL COMPONENT, DIAGNOSTIC METHOD OF ROTARY MACHINE, AND DIAGNOSTIC DEVICE OF ROTARY MACHINE

摘要

To remove frequency component of electromagnetic vibration caused by an inverter power supply in a high accuracy from a signal of a vibration sensor mounted on a rotary machine driven by the inverter power supply.SOLUTION: A removal method of electromagnetic vibration component is given in which: Fourier transformation is performed with respect to vibration time waveform obtained by a vibration sensor to calculate frequency spectra; maximum peak frequency being an integral multiple of carrier frequency of inverter power supply is regarded as reference frequency; auto-correlation function of frequency spectra near the reference frequency is calculated; peak interval of the auto-correlation function near the reference frequency is obtained; peak in every peak interval that is equal interval peak near the reference frequency is extracted as object peak; and level of frequency component of the object peak is reduced in the frequency spectra.SELECTED DRAWING: Figure 1