Tachometer-free rotating machinery fault feature extraction method under variable rotating speed

Abstract

The invention relates to a tachometer-free rotating machinery fault feature extraction method under a variable rotating speed. The method comprises the steps of firstly adopting a narrow-band filtering method to eliminate an interference frequency component and most random noise in the vibration data; then dividing the filtered vibration data into a plurality of sections by adopting a short-time sliding window method, further extracting the rotation frequency or the rotation frequency harmonic frequency of the vibration data in each short time period by utilizing a matching pursuit method, andfinally synthesizing the instantaneous rotation frequency or the instantaneous rotation frequency harmonic frequency of the vibration data in the whole time period; and performing order tracking analysis on the original vibration data according to the extracted instantaneous rotation frequency or instantaneous rotation frequency harmonic frequency to realize the fault feature extraction of a variable rotating speed machine without a tachometer. The instantaneous rotation frequency or instantaneous rotation frequency harmonic frequency extracted by the method designed by the invention is highin precision, and under the condition of small random noise interference, the precision of the extracted instantaneous rotation frequency or instantaneous rotation frequency harmonic frequency is close to the measurement precision of the tachometer, so that the accurate extraction of the variable rotating speed rotating machine fault features can be realized.

Description

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine

Login to view more

AI Technical Summary

Benefits of technology

This technology allows for precise detection of frequencies that are caused by sudden changes in rotation speed without being affected by any external factors like temperature fluctuations or other things affecting their performance.

Problems solved by technology

This patents discusses different types of fault detection techniques used during machine maintenance operations like oil leakage inspections and shaft impact tests. These tools use various sensors called accelerometers to measure the velocity of machines' motion while varying speeds. They also include advanced analyzer systems that capture both amplitude and phase angle variations from these measurements. By analyzing these variables, they provide more detailed information about the state of the machine being tested compared against known reference values. Overall, current fault detect algorithms suffer limitations in terms of their ability to effectively distinguish between normal operating mode and fast changing modes of the engine.

Images