Petroleum Pipe Leakage Detection and Location Embeded in SCADA

With the increase of the age of the transport oil pipeline and the man-made destruction to pipeline, leaks are often found. The system for pipeline leakage detection and location must be established to find leakage and locate the leak positions to reduce serious environmental pollution and economic loss caused by leakage. The negative pressure wave method is an effective way to locate the leak position, because over 98 percent pipe leakage in China is paroxysmal. There is a SCADA (supervisory control and data acquisition) system to monitor operation for long transport petroleum pipe, but the function of leakage detection and location is not included in existing SCADA system in China. This paper used Dynamic Data Exchange (DDE) method to obtain pipe operation parameters such as pressure, flow rate, temperature, bump current, valve position and so on from the SCADA system. That takes full advantage of the abundant data collection function of the SCADA system to provide data for leakage detection and location. The wavelet packet analysis-based fault diagnosis method can directly use the change of parameters such as energy of frequency component to detect faults without system model. In the paper, a wavelet packet analysis-based characteristic extraction method is used to extract the characteristic information of leak pressure signals. The eigenvector indexes along with the parameters obtained from the SCADA system can be used to avoid false alarms. Wavelet analysis was used to locate leak positions accurately in this paper. Such a wavelet analysis-based leakage detection and location scheme embedded in the SCADA system has been successfully applied to a pipeline in PetroChina. Practical run demonstrated its well effect.