Pipeline multi-point leakage accurate positioning method

Abstract

The invention provides a pipeline multi-point leakage accurate positioning method. Firstly, original signals are decomposed into the sum of several IMFs by using an improved CEEMD; then envelope signals of the IMFs in all orders are calculated, and a sample entropy of each envelope signal is calculated; then according to the size of sample entropy values, the IMFs in all orders are optimized, andthen the preferred IMFs are reconstructed and are subjected to dimension raising; single leak source signals are separated through a blind source separation and signal sparsity combined manner; and finally, a time difference positioning formula is used for positioning leakage points. The experimental results show that the method is suitable for pipeline multi-point leakage detection and location,the pipeline leakage positioning accuracy can be improved to a large extent, and the powerful theoretical basis and practical experience are provided for practical engineering application.

Description

technical field [0001] The invention relates to the technical field of pressure pipeline leakage detection, and more specifically relates to a method for accurately locating pipeline multi-point leakage based on improved CEEMD and blind source separation. Background technique [0002] During the long-term use of urban pipelines, it is easy to cause leakage due to various factors such as internal and external corrosion. Especially the small leaks that occurred in the early stage, due to the characteristics of small leak hole diameter and small leakage flow rate, it is difficult to capture small leaks through visual, auditory and pipeline detection systems. In actual working conditions, pipeline leakage is usually formed by the interaction of multiple leakage points, and multi-point leakage often has the characteristics of large signal interference and signal content, which makes it difficult to extract multi-point leakage signals and cause large positioning errors, which pose...

AI Technical Summary

Problems solved by technology

However, the existing blind source separation technology still has certain limitations: on the one hand, most of the current blind source separation algorithms are for overdetermined or positive definite situations, that is, the number of observed signals is required to be greater than or equal to the number of source signals, and for underdetermined situations ( The number of observed signals is less than the number of source signals) is not satisfied, resulting in a certain aliasing of the separated source signals, which affects the final diagnosis result

On the other hand, the real pipeline leakage signal has the characteristics of non-stationary and nonlinear, and the existing methods usually perform poorly in dealing with such signals.

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