A method for extracting rotor dynamic balance fault features under keyless phase transition speed

Abstract

A method for extracting fault features of rotor dynamic balance under keyless phase change rotation speed, comprising: performing band-pass filtering noise reduction processing on collected vibration signals; Analysis, get the time-frequency energy distribution; use the Sobel operator to calculate the energy gradient, and use the dynamic programming algorithm to search for the target ridge line with the minimum energy gradient to adjust the discontinuity of the ridge line change caused by noise, and realize the instantaneous vibration signal of variable speed. Accurate estimation of rotational frequency; according to the extracted instantaneous rotational frequency, the vibration signal after noise reduction processing is subjected to order tracking calculation and discrete spectrum correction, and the amplitude and phase corresponding to the first-order spectrum are extracted. The invention can overcome the interference of adjacent frequency and strong noise, realize accurate extraction of dynamic balance fault features of variable-speed rotor without key phase signal, save hardware cost and improve dynamic balance efficiency.

Description

technical field [0001] The invention relates to the field of rotor dynamic balance fault diagnosis and signal analysis and processing under variable rotation speed, in particular to a method for extracting rotor dynamic balance fault features under keyless phase change rotation speed. Background technique [0002] With the rapid development of production technology and equipment manufacturing industry, the structure of mechanical equipment has become more and more complex. Among the rotating parts of these complex equipment, most of them use the rotor as the main working part. Rotor imbalance is gradually becoming a major cause of rotating machinery failures. Vibration signal is the most important source of information in the process of monitoring and diagnosing complex equipment. It can directly reflect the operating state of the equipment and contains rich fault information. It is usually used in rotor imbalance fault diagnosis. The traditional rotor unbalance fault diagn...

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Problems solved by technology

Chinese invention patent 201911285855.2 proposes a method for feature extraction of rotating machinery faults without a tachometer at variable speeds. This method is based on the assumption that the speed of the signal will not change in a short period of time (such as 1-4 cycles), with the help of matching pursuit method Realize the extraction of instantaneous frequency of rotating machinery with variable speed, but it is not suitable for the situation where the speed fluctuates violently, and even seriously affects the extraction accuracy of instantaneous frequency

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