Diagnosis method for low-frequency fluid vibration excitation failure of compressor based on axial vibration analysis

Abstract

The invention discloses a diagnosis method for a low-frequency fluid vibration excitation failure of a compressor based on axial vibration analysis. The method comprises the steps that an acquired shaft vibration signal is resolved into a direct current component and a dynamic alternating current component; then dynamic signal frequencies related to axial movement of a rotor are removed by coherence analysis; a residual frequency spectrum is continuously refined by further local frequencies; fluid impact characteristic frequency range energy in a low-frequency component is analyzed; analysis and comparison with a typical failure characteristic signal are conducted; and the low-frequency fluid vibration excitation failure can be quickly distinguished and judged. With the adoption of the method, quantification description of states of vane blades impacted by abnormal fluid is conducted with energy spectrum density of a low-frequency air flow characteristic frequency range, and the low-frequency fluid vibration excitation failure is accurately identified and quantified, tracked and monitored in real time through trend tracking analysis.

Description

technical field [0001] The invention relates to a fault diagnosis technology for the operating state of a compressor, in particular to a method for quickly discriminating and quantitatively tracking and monitoring low-frequency vibration faults by using axial vibration signals of a compressor. Background technique [0002] During the operation of the compressor, in addition to the faults of the rotation frequency, due to the adjustment of the working conditions, the irregular daily operation and the problems of the blades, impellers, valves, and flow channels, the faults of the low-frequency (frequency between 0 and the rotation frequency) fluid excitation, It mainly includes more than ten kinds of low-frequency nonlinear faults, such as oil film whirl, oil film oscillation, clogging, rotation detachment, airflow excitation, surge, air seal wear, support looseness and pipeline excitation. Such faults occur frequently. Especially under the action of cyclic stress such as long...

AI Technical Summary

Problems solved by technology

This traditional method cannot accurately divide the fault frequency in the characteristic boundary area and overlapping area, nor can it quantify the type of low-frequency fluid excitation fault (such as oil film oscillation, air flow excitation, flow field disorder, etc.) Monitoring and tracking

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