Study On Distributed Optical Fiber Sensor For Detection And Positioning Of Oil Pipeline Ice Blocking

For the problem that pipeline's ice block detection and location technology in alpine region, after studying the distributed optical fiber sensing technology deeply, proposing the pipeline's detection and location technology based on optical fiber sensor. This method can not only detect the ice block's condition of buried pipelines and point the position of ice block, but can warn the exception of the oil pipeline security.The proposed pipeline using distributed optical fiber testing method of the ice block, the use of optical fiber interferometer principle design of a distributed optical fiber sensors.Analyze the detection principle of distributed optical fiber sensors and study the detection system's sensitivity and the factors which affect sensitivity, then ,proposing the solution: design a highly sensitive sensor cable structure.Design the pipeline ice blocking inspection system which is based on the distributed fiber sensor, and analyze the components of detection system. propose the method that using detection signal's time difference of distributed optical fiber sensor to locate the pipeline accidents, which is based on distributed optical fiber sensor's checking principle. Using correlation function to calculate the time difference of the sensor signal. Through the relevant time difference measurement, reduce the detection signal time difference's computation. So improve the detection system's real-time and accuracy.Study the characteristics of test signal and processing technology. through analyzing the principles and methods of wavelet threshold denoising, Using wavelet threshold denoising to remove noise of the detection signal. In this paper, proposing the"Energy-Mode"feature vector extraction which is based on wavelet packet analysis. analyze the characteristics of virtual instrument technology, design the detection software system of distributed optical fiber pipeline ice block based on virtual instrument technology. Completing signal acquisition, processing ,storage and computing related.At present, In china, the oil pipeline is in the comprehensive update stage. In this paper, proposing the sensing technology based on distributed optical fiber, and it can detect and accurately locate the ice block pipeline. In addition, fiber itself has electrical insulation, it is safe and reliable in essence, and it has the characteristics of corrosion-resistant in the environment which is full of strong electromagnetic interference, flammable, explosive, strong corrosion in petrochemical industry. So it make the distributed optical fiber sensing detection system has a wide range of applications.