通过在线监测和分析管道破坏时产生的应力波信号特征,实现对盗油打孔位置的快速、准确的测定。监测系统采用基于远程无线通信网络的主-从机分布式结构形式。主机系统负责系统运行的管理与控制、应力波信号特征提取和定位计算;从机系统负责采集管道应力波信号。打孔应力波信号特征采用基于Hilbert—Huang变换的时频域信号处理方法提取,并结合时差定位算法实现了对打孔位置的精确定位。现场实验测试与实际运行结果表明,本监测系统定位平均误差小于10m,报警准确率达到90%以上,系统响应时间小于10s。
An online monitoring system was developed for rapidly and exactly locating the holing position in oil pipeline based on monitoring and analyzing the characteristic of the stress wave caused by holing in the pipeline. The system has a master-slave computer structure based on a remote wireless communication network. The master system takes charge in managing and controlling the whole system, extracting the signal characteristics of the stress wave and calculating the holing position. The slave system is responsible for acquiring the stress wave signal from the pipeline. The characteristics of the stress wave signal are extracted using a Hilbert-Huang transform based time-frequency domain signal processing approach. And the holing position can be exactly obtained by a time delay locating method from the stress wave signal characteristics. The experimental results on the in-service pipeline show that the average locating error of the system is less than 10 m, and the correct rate for the holing alarm is higher than 90% , and the system response time for leakage is less than 10 s.