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分布式光纤管道泄漏检测及预警技术灵敏度分析 总被引:1,自引:1,他引:0
针对管道安全存在的问题,提出了一种基于Mach-Zehnder光纤干涉仪原理的分布式光纤管道泄漏检测及预警技术,利用与管道同沟敷设的光缆中的3条单模光纤构成分布式光纤微振动传感器检测管道沿线的振动信号,可以有效地检测管道沿线所发生泄漏和异常事件.分析和研究了检测系统的测试灵敏度影响因素,并采用不同光缆结构和埋设方式对检测系统的检测灵敏度进行测试.实验结果表明,该检测技术可以检测到1m范围内的人工挖掘信号,在气体管道压力不小于0.2MPa的条件下,可以检测到0.4m^3/min的气体管道泄漏. 相似文献
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介绍了一种基于马赫-曾德尔和萨格纳克混合干涉仪原理的分布式光纤天然气管道泄漏检测系统.阐述了检测系统的检测原理及泄漏定位方法,在泄漏点距法拉第旋转镜为6 032m处进行了气体管道泄漏检测实验并重复做了20次试验,测试了传感光纤与泄漏点不同夹角对检测系统性能的影响.实验结果表明,该系统可以检测出管道内气体压力为0.3MPa、泄漏孔径为2.5mm的微小泄漏信号并进行定位,平均相对定位误差为1.29%.在40mm的管道外径下,传感光纤与泄漏点夹角在0~180°范围内,检测系统均能检测出泄漏信号并进行定位. 相似文献
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随着我国社会经济的不断发展和进步,从而使得对于能源的需求也越来越大,特别是油气资源。在运输油气资源的过程当中,因为管道具有自身的一些优势,所以它成为了运输油气资源的一种非常重要的手段。但是在实际的运输中,因为很多人为因素和自然因素,经常都会发生管道泄漏的事故,这样对于环境的污染以及人们的生命财产都有非常严重的影响。文章主要针对分布式光纤油气长输管道泄漏检测及预警技术进行研究和分析。 相似文献
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针对电力设备局部放电检测灵敏度要求较高的问题,提出不同长度的延迟光纤对基于干涉型Sagnac光纤传感技术的局部放电超声检测系统灵敏度的影响,设计电力设备局部放电模拟装置,搭建干涉型Sagnac光纤法检测局部放电系统,进行局部放电光纤法检测灵敏度理论分析与试验验证。试验证明,在10 kV电压等级下,传感光纤长度在10 km以内,当延迟光纤的长度约为12~18 km时,局部放电频域信号中心频率强度有最大值;当延迟光纤长度为12.353 km时,传感光纤对局部放电时域信号响应的灵敏度较高。研究表明,调节合适的延迟光纤长度,可以提高干涉型Sagnac光纤法检测局部放电时域和频域信号的灵敏度,可为电力设备局部放电光纤法检测灵敏度的提升提供新的思路。 相似文献
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提出了基于小波能谱和小波信息熵的油气管道异常振动事件识别方法。基于Mach-Zehnder光纤干涉仪原理的分布式光纤油气管道安全监测系统实时检测管道沿途振动信号,对测量的时间序列进行小波变换,根据小波系数计算小波能谱与小波信息熵,通过小波能谱和小波信息熵值两种测度识别不同的管道安全异常事件。港枣线成品油管道的现场实验结果表明,该方法可以快速有效地识别管道周围发生的泄漏及其他异常情况,其总体识别准确率达到98.5%,有效降低了误报警率,具有较强的在线工况识别能力。 相似文献
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Potapov V. T. Mamedov A. M. Ignatov B. G. Potapov T. V. 《Technical Physics Letters》2011,37(6):586-588
Coherent fiber-optic reflectometer with a single-mode (λ = 810 nm) semiconductor laser as a radiation source has been experimentally
studied. It is demonstrated that distributed fiber-optic sensors for detecting and locating dynamic impacts can be created
based on the proposed reflectometer with a fiber circuit length of up to 3 km. 相似文献
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提出了一种以光纤分布式扰动传感器为核心,通过随油气管线一同敷设的标准通信光缆为传感介质的新型光纤管线预警系统.该系统利用激光干涉的原理对扰动信号进行实时探测,从而实现对挖掘、偷盗和第三方破坏等事件导致的扰动的实时监测和定位,从而达到管线安全预警的功能.该预警系统成功研制后分别在津唐输油处石油管线和杭州至嘉兴天然气管线进行了多次外场测试,该系统能在长达60 km的管线上实现250 m的定位精度,具有很好的定位稳定性.其测试结果表明:与传统油气管线监测手段相比,该系统具有无需外场供电、本质安全、灵敏度高,监测距离长、可定位以及可预警监测等技术优势,是未来油气管线监测的发展趋势. 相似文献
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We demonstrate a simple method to extend the measurable fiber length with a fiber-optic low-coherence technique. This method is based on a cascaded structure of multistage fiber delay line laid in one arm of the low-coherence technique. By choosing different individual stages in the cascaded fiber delay line, the length of the fiber under test can be continuously measured with a different measurement range. The measurement range of 0.81 km and spatial resolution of 60 μm are successfully realized. 相似文献
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Yu. N. Kul'chin O. B. Vitrik O. V. Kirichenko Yu. S. Petrov 《Measurement Techniques》1994,37(1):26-28
The operating principle of a quasidistributed fiber-optic pickup based on internodal interference in weakly guiding fiber waveguides is considered. The pickup can be used as both an independent measuring instrument and a base element in the fabrication of fiber-optic distributed measuring networks.Translated from Izmeritel'naya Tekhnika, No. 1, pp. 16–17, January, 1994. 相似文献
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为了解决恶劣环境下分布式光纤声音传感系统的声音还原问题,搭建了一种基于改进最小控制递归平均(IMCRA)算法的多通道光纤声音传感系统。采用Sagnac和Mach-Zehnder复合光路结构,以单模光纤作为传感单元拾取声音信号,借助光开关实现了多通道信号采集,并通过改进最小控制递归平均算法对声音信号进行降噪、还原及增强处理。实验结果表明:该系统可在长为4km的传感光纤上实现对单音信号和语音信号的多通道扫描拾取,并能够在复杂情况下实现对语音信号信噪比的有效提升,为光纤声音传感系统在恶劣环境下的应用提供了一种新途径。 相似文献
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Sensors capable of making distributed measurements allow for monitoring of the entire structure. Optical fiber sensors are especially attractive for this purpose, since they are geometrically versatile and can be readily integrated within various types of structure and material. Development and characteristics of a quasi-distributed intrinsic fiber-optic strain sensor based on white-light interferometry are described. The research presented here describes the development of a new optical fiber sensor system for measurement of structural strains based on double white-light interferometry. Individual segments of single-mode optical fibers forming a common-path interferometer are linked in series, and a scanning white-light interferometer provides for distributed sensing of strain signals from various locations in the structure. The system is configured for automatic compensation of drift due to environmental effects, i.e., temperature and vibration. Strain gauges were employed for comparison and verification of strain signals as measured by the new system. The experimental results demonstrate the linearity of the system and the capability for distributed sensing of strains. 相似文献
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A simple fiber-optic sensor based on Fabry-Perot interference for refractive index measurement of optical glass is investigated both theoretically and experimentally. A broadband light source is coupled into an extrinsic fiber Fabry-Perot cavity formed by the surfaces of a sensing fiber end and the measured sample. The interference signals from the cavity are reflected back into the same fiber. The refractive index of the sample can be obtained by measuring the contrast of the interference fringes. The experimental data meet with the theoretical values very well. The proposed technique is a new method for glass refractive index measurement with a simple, solid, and compact structure. 相似文献
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Real-Time Structural Health Monitoring Using a Novel Fiber-Optic Accelerometer System 总被引:1,自引:0,他引:1
Dae-Hyun Kim Maria Q. Feng 《IEEE sensors journal》2007,7(4):536-543
This paper presents a novel fiber-optic accelerometer system to monitor civil engineering structures in real time and a successful application of the novel sensor system for damage detection of the concrete slab structure. This sensor system integrates the Moireacute fringe phenomenon with fiber optics to achieve accurate and reliable measurements. A signal processing unit implements unique algorithms to further enhance the resolution and increase the dynamic bandwidth of the sensors. The sensor system is immune to electromagnetic (EM) interference, making it suitable for difficult applications in such environments involving strong EM fields, electrical spark-induced explosion risks, and cabling problems, prohibiting the use of conventional electromagnetic accelerometers. Especially, this paper presents a unique real-time signal processing algorithm and applications to real-time damage assessment, demonstrating the uniquely high performance of the Moireacute fringe fiber-optic sensor system 相似文献
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Distributed Feedback Fiber Laser Strain Sensors 总被引:3,自引:0,他引:3