Leakage locating method combining self-adapting threshold value leak detection and multi-dimension fast delay time search

Abstract

A leak positioning method combining self-adapting threshold value leak detection and multi-scale rapid time delay search belongs to the malfunction diagnosis technology field of oil (gap) pipeline, wherein pressure data at both ends of the pipeline and standard error of re-constructing signal difference value of the data based on orthogonal wavelet transformation de-noising process multiplying coefficient as threshold values at both ends. If average values before or after catastrophe point when the pressure at both ends reduces exceed the threshold value, judging that there is leak and positioning: calculating approximate wavelet transformation coefficient of pressure data at both ends, initializing searching interval, calculating a signal time delay value corresponding to approximate wavelet transformation coefficient in the searching interval from maximal scale N; converting the time delay value under scale N to that under N-1 by geometric proportion relation; updating the searchinginterval, repeating above processes until the scale is 0 and positioning based on the time delay value. The invention is capable of reducing rate of false report and rate of missing report effectively, reducing time delay estimated calculated amount, which is beneficial to accomplish arithmetic online.

Description

Technical field: [0001] A leak location method based on adaptive threshold leak detection combined with multi-scale fast time-delay search belongs to the technical field of oil (gas) pipeline fault diagnosis. Background technique: [0002] Pipeline transportation occupies an important position in the transportation of industrial fluids, especially oil and natural gas. Pipeline leakage monitoring is an important content of pipeline operation monitoring, which promotes the continuous development of pipeline leakage detection technology. At present, there are many pipeline leak detection methods, from the simplest manual inspection to various complex software and hardware algorithms. These algorithms play an important role in maintaining pipeline safety and protecting the environment. [0003] Among the existing pipeline leakage detection and location methods, the method based on negative pressure wave has been widely used in practice because of its simple implementation, low s...

AI Technical Summary

Problems solved by technology

The patent [name: time-frequency cross-correlation detection and time-delay estimation method of scanning signals, public number: CN1815264A, public date: 2006.8.9, China] proposes a time-delay estimation method based on wavelet transform, but its processing purpose is to Suppress noise, and the wavelet transform used is continuous wavelet transform, so there is also the problem of large amount of calculation

For the pipeline leak location problem, due to the long pipeline distance, high data sampling rate, large amount of data, and the requirement of timely location, the calculation problem is particularly prominent. Using the traditional time delay estimation method will not be conducive to the online implementation of the leak detection algorithm.

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