Abstract: A new distributed optical fiber pipeline leakage detection technology based on the principle of Mach-Zehnder optical fiber interferometer is proposed.An optical cable should be laid along the pipeline when applying this technology to pipeline leakage detection.The distributed micro-vibrant measuring sensor is composed of three single mode optical fibers in the optical cable.The oil leakage can be detected by the sensor in real-time by measuring leaked noise along pipeline.The position of leaking point can be obtained by defining the value of time delay of the two measuring signals with the generalized correlation time delay estimation algorithm.This technology is applicable for various oil and gas pipeline leakage detection.The measuring principle and the leaking point location method for this technology are described.The experiment result showed that this technology can greatly improve the measuring sensitivity and detecting precision of leakage location on pipeline.

Key words: pipeline, leakage detection technology, optical fiber interferometer, sensor, location technique, time delay estimation algorithm

摘要： 提出了一种基于Mach-Zehnder光纤干涉仪原理的新型分布式光纤管道泄漏测试技术.该检测技术利用在管道沿线附近敷设的一条光缆中的3条单膜光纤构成分布式微振动测试传感器,通过检测管道沿途所发生的泄漏噪声,可以实时地监测管道沿线所发生的泄漏情况.利用广义相关时延估计算法,通过确定2个测试信号的时延可以获得泄漏点的位置.阐述了该检测技术的测试原理和泄漏点定位方法,并对现场试验数据进行了分析.理论分析和试验结果表明,该测试技术可以有效地提高管道泄漏测试的灵敏度和定位精度.

关键词: 管道, 泄漏检测技术, 光纤干涉仪, 传感器, 定位技术, 时延估计算法