中国石油大学学报(自然科学版)
中國石油大學學報(自然科學版)
중국석유대학학보(자연과학판)
JOURNAL OF CHINA UNIVERSITY OF PETROLEUM(EDITION OF NATURAL SCIENCE)
2014年
6期
153-160
,共8页
孟令雅%刘翠伟%刘超%李玉星%刘光晓
孟令雅%劉翠偉%劉超%李玉星%劉光曉
맹령아%류취위%류초%리옥성%류광효
输气管道%泄漏信号%干扰信号%相关性分析
輸氣管道%洩漏信號%榦擾信號%相關性分析
수기관도%설루신호%간우신호%상관성분석
natural gas pipeline%acoustic leakage signal%interference signals%correlation analysis
输气管道音波法泄漏检测采集得到的信号不仅包含有用的泄漏信号,而且包含背景噪声和各种干扰信号,因此信号的识别和特征量提取尤为重要。基于此情况,采用相关性分析的方法对传感器采集的信号进行处理并得到有效特征量,传感器采集得到的信号包括泄漏信号、敲击信号、压缩机启停信号、减压阀开关信号。相关性分析采用相关函数和协方差函数实现,相关函数可以得到各种信号的自相关和互相关特征,协方差函数可以得到各种信号的自协方差和互协方差特征。同时对信号进行整体峰度计算,并设置整体峰度阈值。研究结果表明:信号的相关性分析可以对输气管道微泄漏进行检测,同时对诸如减压阀操作、压缩机启停、敲击等干扰因素可以通过相关函数数值从背景噪声中识别;在不确定是否存在干扰信号的前提下,通过相关分析从背景噪声中提取泄漏信号或干扰信号,并对信号进行整体峰度值计算,若整体峰度值高于阈值,则认为泄漏发生,提高了音波泄漏检测的准确性。
輸氣管道音波法洩漏檢測採集得到的信號不僅包含有用的洩漏信號,而且包含揹景譟聲和各種榦擾信號,因此信號的識彆和特徵量提取尤為重要。基于此情況,採用相關性分析的方法對傳感器採集的信號進行處理併得到有效特徵量,傳感器採集得到的信號包括洩漏信號、敲擊信號、壓縮機啟停信號、減壓閥開關信號。相關性分析採用相關函數和協方差函數實現,相關函數可以得到各種信號的自相關和互相關特徵,協方差函數可以得到各種信號的自協方差和互協方差特徵。同時對信號進行整體峰度計算,併設置整體峰度閾值。研究結果錶明:信號的相關性分析可以對輸氣管道微洩漏進行檢測,同時對諸如減壓閥操作、壓縮機啟停、敲擊等榦擾因素可以通過相關函數數值從揹景譟聲中識彆;在不確定是否存在榦擾信號的前提下,通過相關分析從揹景譟聲中提取洩漏信號或榦擾信號,併對信號進行整體峰度值計算,若整體峰度值高于閾值,則認為洩漏髮生,提高瞭音波洩漏檢測的準確性。
수기관도음파법설루검측채집득도적신호불부포함유용적설루신호,이차포함배경조성화각충간우신호,인차신호적식별화특정량제취우위중요。기우차정황,채용상관성분석적방법대전감기채집적신호진행처리병득도유효특정량,전감기채집득도적신호포괄설루신호、고격신호、압축궤계정신호、감압벌개관신호。상관성분석채용상관함수화협방차함수실현,상관함수가이득도각충신호적자상관화호상관특정,협방차함수가이득도각충신호적자협방차화호협방차특정。동시대신호진행정체봉도계산,병설치정체봉도역치。연구결과표명:신호적상관성분석가이대수기관도미설루진행검측,동시대제여감압벌조작、압축궤계정、고격등간우인소가이통과상관함수수치종배경조성중식별;재불학정시부존재간우신호적전제하,통과상관분석종배경조성중제취설루신호혹간우신호,병대신호진행정체봉도치계산,약정체봉도치고우역치,칙인위설루발생,제고료음파설루검측적준학성。
The signals acquired by acoustic leak detection method for natural gas pipelines include useful leakage signal, background noises and interference signals. Therefore, the recognition and characteristics extraction of leakage signal are get-ting more and more important. The measured signals including leakage signal, knocking signal, compressor shutoff signal, compressor starting signal, regulator closing signal and regulator openning signal were processed by correlation analyses meth-od based on correlation and covariance function. The characteristics of auto-correlation and cross-correlation were extracted. The results show that the correlation analyses can extract the characteristics of leakage signals and other interference signals from the background noises. Then the overall kurtosis can be applied to distinguish the leakage signals from the interference signals. The characteristics extracted by correlation analyses are effective for recognizing leakage signal among the noises and the characteristics of the overall kurtosis can be used to detect leakage signals among all acquired signals if the threshold val-ue of the overall kurtosis is set, which has a strong impetus to the improvement and application of acoustic leak detection technology.