C-052 太原理工大学_白清_用于油气长输管道地质灾害预警的BOTDR技术.pdf

用于油气长输管道地质灾害预警的BOTDR技术 * 白清，王云才 ，靳宝全，刘毅，王东 (太原理工大学 新型传感器与智能控制教育部与山西省重点实验室，山西 太原 030024 ） 摘 要： 地质灾害预警是保证长输管道安全运营急需解决的重要问题。为解决传统长输管道地质灾 害预警技术存在的测点分散、预警网络复杂度高、全程覆盖困难等问题，设计了一种利用布里渊光时 域反射 （BOTDR ）技术实现分布式应变测量的监测方案。方案采用声光调制器产生脉冲探测光进入传感 光纤，利用相干探测的方式获取拍频信号，同时结合外差式频率扫描的方法解调布里渊增益谱，从而得到 布里渊频移量随传感光纤距离的分布曲线，最终实现应变的分布式测量。实验结果证明，该方案传感距离 可达10.2km，空间分辨率为3m，布里渊频移解调精度为±0.88MHz ，相当于应变测量精度为40με ，基本满足 长输管道地质灾害预警技术的指标要求。 关键词：应变检测；布里渊光时域反射；分布式测量；地质灾害预警 BOTDR technique applied for the geological hazard forecast-warning of long-distance oil or gas pipelines BAI Qing ，WANG Yun-cai * ，JIN Bao-quan ，LIU Yi ，WANG Dong Key Laboratory of Advanced Transducers and Intelligent Control Systems (Ministry of Education and Shanxi Province), Taiyuan University of Technology, Taiyuan 030024, China; *Corresponding author: WANG Yun-cai E-mail: wangyc@tyut.edu.cn Abstract: The geological hazard forecast-warning is a significant issue for security operation of long-distance oil or gas pipelines. However, several problems existed in traditional techniques of geological hazard forecast-warning commonly. For instance, superabundant decentralized measure points and too complex network components increases the difficulty of the whole coverage. To solve these problems, a strain measurement scheme was designed based on Brillouin optical time domain reflectometer (BOTDR) technique. In the scenario, the pulse probe light modulated by an acoustic optical modulator was launched into sensing optical fibers and we eventually obtained the beat frequency signal through coherent detection. Then, the Brillouin gain spectrum was figured out via heterodyne frequency sweeping. Ultimately the curve of Brillouin frequency shift (BFS) versus sensing fiber length was plotted to real