Filtering optimal selection method for leakage sound wave signals of gas transmission line

Abstract

The invention discloses a filtering optimal selection method for leakage sound wave signals of a gas transmission line. The method includes the steps that the falling edge length of the leakage sound wave signals serves as the signal length of signals with the amplitude suddenly falling to the amplitude which restores to zero; the time domain waveform of true leakage sound wave signals is fitted to obtain fitted leakage sound wave signals; noise signals are added, so that pseudo leakage sound wave signals are obtained; filtering processing is conducted on the pseudo leakage sound wave signals through various pre-selected filtering methods, and the waveform after filtering is obtained; the evaluation index of the filtered signals is calculated and obtained, the optimal filtering method is determined, and the effectiveness of the optimal filtering method is verified through the true leakage sound wave signals. According to the filtering optimal selection method for the leakage sound wave signals of the gas transmission line, the requirements of SNR evaluation index maximum, root-mean-square error evaluation index minimum and leakage falling edge amplitude loss evaluation index minimum are met, the optimal filtering method is selected, the filtering effect of the leakage sound wave signals is quantificationally evaluated, the SNR of the leakage sound wave signals is increased, and the applicability of a sound wave method leak detection technology is improved.

Description

technical field [0001] The invention belongs to the technical field of signal processing and pipeline safety monitoring, and in particular relates to a method for filtering and optimizing the leakage sound wave signal of a gas transmission pipeline. Background technique [0002] The sensor used in the sonic method leak detection technology is a dynamic pressure sensor. The sensor takes the pressure pulsation of the fluid in the pipe as the output value. There is a pulse drop in the amplitude, and then quickly recovers to fluctuate around zero. The leakage falling edge is the basis for leak judgment, but its duration is short and the waveform changes sharply. At the same time, the leakage sound wave signal is attenuated during the propagation process. The superimposition of background noise and interference makes the filtering process of the leaked sound wave signal very difficult. [0003] The difference in pipeline diameter, structure and operating environment leads to dif...

AI Technical Summary

Problems solved by technology

[0012] The purpose of the present invention is to provide an optimal method for filtering the leakage sound wave signal of the gas transmission pipeline, aiming at solving the problem of lack of a filtering method for the leakage sound wave signal at the present stage

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