Complete alternation synchronous sampling and analyzing method for rotating machinery vibration signals

Abstract

The invention discloses a complete alternation synchronous sampling and analyzing method for rotating machinery vibration signals. The complete alternation synchronous sampling and analyzing method includes that fixed sampling frequency collects vibration signals and key pulse signals continuously and synchronously, revolving speed and instantaneous frequency are acquired according to the key pulse signals, average-angle sample time series are acquired by interpolation filters, re-sampling is performed according to anti-aliasing digital filtering and interpolations to acquire vibration equal-angle sampling signals, and finally vibration order ratio spectra and harmonic wave forms of each order are finally acquired. By the synchronous sampling and analyzing method, accurate equal-angle sampling can be realized; and further, hardware is omitted, cost is reduced, and performance is reliable and stable.

Description

technical field [0001] The invention relates to a method for processing a vibration signal of a rotating machine, in particular to a method for synchronously sampling and analyzing the vibration signal of a rotating machine for the entire cycle. Background technique [0002] Vibration analysis is the most widely used method in fault diagnosis of rotating machinery. On the one hand, the vibration problem is one of the most important safety issues in the operation of rotating machinery. On the other hand, the vibration signal contains a wealth of information about the operating status of the machinery. When a rotating machine is running, its rotational speed fluctuates in a strict sense, especially during the speed up and down phases, and the vibration signals corresponding to these states are non-stationary signals. The analysis of these non-stationary vibration signals can reveal its frequency characteristics, especially the law of its frequency changing with time or speed, ...

AI Technical Summary

Problems solved by technology

This method is quite effective when the rotational speed of the rotating machine is constant or changes little, but when the rotational speed of the rotating machine changes greatly, the update frequency at this time is calculated from the frequency at the first sampling; therefore, when using this update frequency and Equiangular resampling of the speed pulses on the current high-speed shaft will cause the update frequency to be out of sync with the speed pulses on the current high-speed shaft, and the sampling data will be inaccurate

Therefore, the traditional order ratio analysis method is used in variable speed machinery, especially when the speed up and down speed is high. Since the instantaneous frequency cannot be tracked, it can only be preset, and because the equiangular resampling is resampled by hardware, so , the traditional order ratio analysis will have large errors, and even wrong analysis results

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