石油学报 ›› 2012, Vol. 33 ›› Issue (5): 898-903.DOI: 10.7623/syxb201205024

• 石油工程 • 上一篇    下一篇

基于二代小波变换和多级假设检验的输油管道缓泄漏检测方法

赵利强 王建林 于 涛 苟武侯   

  1. 北京化工大学信息科学与技术学院 北京 100029
  • 收稿日期:2012-03-15 修回日期:2012-07-21 出版日期:2012-09-25 发布日期:2012-11-27
  • 通讯作者: 赵利强
  • 作者简介:赵利强,男,1982年6月生,2010年获北京化工大学博士学位,现为北京化工大学讲师,主要从事油气管道的安全监测和智能检测方面的研究。
  • 基金资助:

    北京市自然科学基金项目(No.4082022)资助。

A detection method for slow leakage of oil pipelines based on second generation wavelet transform and multistage hypothesis test

ZHAO Liqiang WANG Jianlin YU Tao GOU Wuhou   

  • Received:2012-03-15 Revised:2012-07-21 Online:2012-09-25 Published:2012-11-27

摘要:

针对输油管道缓泄漏准确判断与定位的难题,提出了一种基于二代小波变换和多级假设检验(MHT)的管道泄漏检测方法。首先,采用基于提升框架的二代小波变换对管道首、末端压力信号进行预处理,分析缓泄漏压力信号的小波分解效果,确定压力信号预处理的小波分解层数。其后,利用低频重构信息为原信号概貌并且能突出信号趋势的特点,将小波分解得到压力信号的各层低频重构信息用于泄漏判断与定位。再后,在给出基于MHT的泄漏判断方法和MHT参数的设置方法基础上,对压力信号的每一层低频重构信息分别进行MHT,并对每层结果进行加权平均,得到压力信号下降沿的准确位置后,利用负压波法实现了管道泄漏定位。实验结果表明,该方法可以准确检测和定位管道泄漏,为输油管道缓泄漏检测提供了一种新的手段。

关键词: 管道缓泄漏检测, 二代小波变换, 提升框架, 多级假设检验, 负压波

Abstract:

When slow leakage occurs in oil pipelines, the trend of pressure signals is relatively slow. At present, there is no effective method to detect the slow leakage and locate the leakage position accurately. A leakage detection method was proposed based on second generation wavelet transform and multistage hypothesis test (MHT). Pressure signals of pipeline ends were preprocessed by second generation wavelet transform within a lifting scheme in order to analyze wavelet decomposed results of slow-leakage pressure signals and to determine layer numbers of wavelet decomposition. The low frequency reconstructed information can give a general picture of original signals and highlight the signal trend, therefore, the low frequency reconstructed information of pressure signals given by wavelet decomposition for each layer can be used to detect slow leakage and locate its position. Based on the leakage judgment method using MHT and the setting method of MHT parameters, we processed the low frequency reconstruction information of pressure signals for each layer, respectively, with the MHT and performed the weighted average on data of each layer. When the exact location of falling edges of pressure signals was determined, the slow leakage of pipelines could be located with the negative pressure wave method. The experiment results show that pipeline slow leakage can be detected and located accurately with this method, and it is an effective way to solve detection problems of slow leakage in oil pipelines.

Key words: pipeline slow leakage detection, second generation wavelet transform, lifting scheme, multistage hypothesis test (MHT), negative pressure wave