【作者】 李利锋；

【导师】 白泽生；

【作者基本信息】 延安大学 ， 信号与信息处理， 2009， 硕士

【摘要】 管道运输系统作为五大运输行业之一,以其环保、经济、快捷等优点,在国民经济中的地位越来越为突出。但是近年来,泄漏已经成为输油管道运行的主要故障,特别是输油管道被打孔盗油以及腐蚀穿孔造成泄漏事故屡有发生,严重干扰了正常生产,造成巨大的经济损失和环境污染。因此,输油管道泄漏检测系统的研究与应用成为油田亟待解决的问题。先进的管道泄漏自动检测技术,可以及时发现泄漏,迅速采取措施,从而大大减少盗油案件发生,降低经济损失,具有明显的经济效益和社会效益。鉴于此,结合我国管道输送的实际情况,并借鉴目前国际上各种泄漏检测与定位的先进方法,针对陕北原油长输管线泄漏故障的特点,本文提出了基于小波分析和负压波相结合的检测泄漏与定位技术。其中,主要进行了以下几方面的工作:1.研究了小波变换与信号奇异性之间的关系,对使用小波变换检测信号奇异点的方法进行了讨论。得出了使用多尺度小波变换捕捉管道两端负压力波的到达时刻,有效地检测出了信号的突变,并能够较好地克服由于噪声存在而给定位带来的误差。2.研究了负压波泄漏检测定位的关键技术,提出了采用全球定位系统(GPS)来统一首末端数据采集系统的系统时间,分析了管道内的流体温度、密度随传输距离变化的规律,并指出了此规律对管道压力波传播速度的影响。指出了常负压力波波速定位方法的局限性,并采用改进的负压力波定位技术,对于沿程传播速度变化的泄漏点定位,采用数值积分的Romberg算法求解泄漏点位置,并提出了两种漏点定位搜索方法。3.利用MATLAB仿真平台,对负压波信号滤噪和负压波信号奇异点的识别,进行了仿真。并通过二分区间搜索算法,仿真得到了相关数据,对泄漏点进行定位。结果证明了本文理论分析的可靠性,以及提高了管道泄漏检测与定位的准确性和及时性。4.最后,本文提出了基于负压波和流量平衡的输油管道泄漏检测定位系统的总体结构和软件设计思想。更多还原

【Abstract】 As one of the five main transport Industries,long pipeline delivery system and its safe operation are of great significant importance due to the serious consequences that may result from different reasons. But in recent years,leakage became the primary malfunction in transporting- oil pipe running. Leakage accident happened frequently because of stiletto steal and decay in the pipeline .It interfered in natural production badly and brought the enormous economic losing and the pollution of the environment so the research and application of the leak detecting system of transporting-oil pipe becomes the urgent Problem .Advanced technology of leak automatic detecting of pipeline can discover the leak duly, and then take action rapidly. It may reduce the happening of steal case, and have obvious economic and social benefit.So, combining with the actual condition of delivery pipeline of our country and some prevalent leak detection and location methods ,this paper raised a method ,which is based on wavelet analysis and negative-pressure-wave to detect and locate the leakage .Jobs in the paper are as follows :1. The relation between wavelet transform and signal singularity and the method of testing signal singularity employing wavelet transform are discussed in the Paper, and gets the multi- scale wavelet transform can detect the arriving time of the pressure wave to the both ends of the Pipeline. The method could detect the break point of the signal and could decrease the error bringing by the existing of impulse yawp.2. Crucial technologies in negative pressure wave method are analyzed in this dissertation, then a means is presented which can adopt Global Position System (GPS) to unify the system time between data collecting systems in two ends. Analysis is done on the change rules of liquid’s temperature along with the pipeline’s distance. The paper points out the defects of the const pressure wave velocity method. Regarding the leaking position along the propagation velocity’s change, using the numerical integration a Romberg algorithm solution divulging position, two searching methods are applied to locate leakage.3. Using MATLAB simulation platform, on the negative pressure wave signal filtering noise and the negative pressure wave signal singular points of identification, simulation. And through algorithm of half divide search, the relevant data by simulating, to locate the leakage point. The results proved the reliability of theoretical analysis in this article, as well as improve the pipeline leak detection and location accuracy and timeliness.4. Finally, the overall structure and ideas of software design, which are the system of leak detection and location for oil pipe based on the negative pressure and flow balanced method, is proposed in the article.更多还原