【作者】 孟凡勇；

【导师】 李志刚；

【作者基本信息】 河北工业大学 ， 电气工程， 2010， 博士

【摘要】 管道输送方式是当前油气产品运输的主要途径,第三方破坏已成为影响油气管道安全运行的最重要因素之一,不仅影响了重要能源产品的可靠稳定供应,还对国家、人民的生命财产安全以及环境安全构成了极大的威胁。目前管道安全检测方法主要依靠基于管道运行参数及管壁状态的检测技术,对于管道泄漏检测有一定的效果,而对于日益严重的管道第三方破坏事故检测效果不佳,只能在泄漏事故发生之后给出报警,由于泄漏造成的能源浪费、环境污染以及其他直接、间接损失无法挽回。因此,急需一种具有对第三方破坏活动具有预警检测能力的管道安全检测技术,在第三方破坏活动实施之初即可给出报警信息,以便相关部门及时采取措施阻止第三方破坏活动的进行,从而有效避免管道泄漏事故的发生。针对油气输送管道特点和第三方破坏活动特征,本文提出了一种基于OFDR技术的第三方破坏活动预警检测方案,设计了基于该检测方案的管道防破坏预警检测系统,对系统各个环节部件的工作原理以及设计方法进行了详细的分析和研究。基于该方案的检测系统用普通单模光纤作为分布式传感器,沿输送线路敷设于管道附近,可以对长距离油气管道实现分布式检测。在传感光纤中准分布式地植入了大规模的光纤光栅阵列,与常规光纤光栅应用不同,在本系统中光纤光栅不直接起传感器作用而是作为光反射器件起反射镜作用。因此,对光纤光栅的参数有特定的要求,本文根据系统原理分析了光纤光栅参数选择的原则,并对其制作方法进行了研究,制作了满足系统使用要求的光纤光栅,完成了传感光纤的制作和光缆的加工。传感光缆对管道沿途伴随第三方破坏活动发出的振动信号进行拾取,通过基于OFDR技术的光外差探测法进行信号探测,根据探测信号特点设计了光电转换与信号调理电路,通过采集卡对检测信号进行了数字化采集。利用专门设计的计算机软件对采集信号进行分析处理,采用信号功率谱分析方法来发现并定位出现在管线沿途的扰动事件,并应用锁相环技术对扰动事件引起的调制信号进行提取,为进一步识别扰动事件的类型、判断扰动事件的性质提供依据。目前设计的传感光缆已经敷设在港-枣(天津大港至山东枣庄)成品油管线沧州至德州段,经多次现场测试其性能满足系统使用要求。作为阶段性成果,目前系统样机已经初具功能,实验室模拟实验及现场测试结果表明,系统方案基本可行,功能有待进一步完善。更多还原

【Abstract】 Pipeline transmission approach is currently the main way to transport oil and gas production. However, the third-party damage has become the most important threat to the safe operation of oil and gas pipeline. It not only affects the steady and reliable supply of important energy products, but also poses a great threat to the safety of the country, people’s lives and property as well as the environment. Current pipeline detection methods rely mainly on pipeline operating parameters and pipe-wall state detection technology, which is effective to pipeline leak detection to a certain degree, but produces poor results in the detection of the growing third party pipeline damages since it only gives an alarm only after the leakage accident. It is impossible to retrieve losses of energy waste, pollution and other direct or indirect caused by leakage. Therefore, the need for pipeline safety inspection techniques with an early warning and detection against the third party damage is urgent so that alarm information can be given to the relevant departments when the third-party damage is caused and timely measures can be taken by those departments to prevent third-party damage activIn connection with the characteristics of oil and gas pipeline and third-party sabotage activities, this paper prop ities. Hence, the occurrence of pipeline leakage accidents can be avoided effectively.oses an early warning and detection program for the third-party sabotage activities based on OFDR technique and fiber Michelson interferometer principles. A pipeline damage prevention, early warning and detection system is designed based on the detection program and detailed analysis and research are conducted on the working principle of every components of the system and its design methods.The detection system of the program adopts ordinary single-mode fiber as distributed sensors, which are laid near the pipeline along the transmission route and enable non-blind area distributed detection of the long-distance oil and gas pipeline. A large-scale quasi-distributed fiber Bragg grating array is implanted in the sensor fiber as multiple reflectors, which forms a fiber Michelson interferometer detection system that has a positioning capability to external perturbations in association with the reflector set in the reference arm of the fiber-optic Michelson interferometer. Being different from the application of conventional optical fiber grating, the fiber Bragg grating in this system does not function as a sensor but as a reflector which reflects light. Therefore, the parameters of the fiber grating have a specific requirement. This paper analyses the selection principles of the fiber grating parameters according to the system principles and studies methods to produce it. Then fiber Bragg grating which meets the requirements of the system is produced and the sensing fiber production and fiber processing are completed. Sensor cable along the pipeline picks up the vibration signals sent out by the third-party sabotage activities, then detects the signals based on OFDR optical heterodyne detection method. It further designs the signal transfer and signal conditioning circuit according to the characteristics of the detected signals and carries out the digital collection of the detection signals through the use of capture card. Specially designed computer software is used to analyze and process the collected signal so that disturbance incidents alongside the pipeline is detected and located using signal power spectrum analysis and vibration information caused by disturbance events is retrieved by the application of the phase-locked loop technology which provide basis for the further identification of the type of disturbance events as well as the determination of the nature of disturbance events.Currently the designed sensor optical cable has been laid in Cangzhou-Dezhou section of the Gang-Zao (Dagang, Tianjin to Zaozhuang, Shandong) oil pipeline. It has been proved to meet the system requirements after several field tests. As the initial results, the current system prototype has already begun to function and laboratory simulation and field test results show that the system solutions are feasible with its functions to be further improved.更多还原