Detection Of Leakage For Complex Pipe Network Based On Pressure Signal Inversion

With the wider application of pipe network in life,the importance of leakage detection is becoming more and more prominent.The leakage of water distribution system(WDS)will not only cause the great waste of water resources and energy,but also cause the secondary pollution of the pipe network,and then produce various kinds of disaster.Therefore,it is very necessary to detect and control the leakage of the water distribution system,especially for the complex water distribution system.So far,there are many methods to detect pipeline leakage at China and abroad.However,the existing water distribution system detection and diagnosis equipment can not achieve a good balance between the accuracy of detection and the cost of equipment investment and maintenance.In order to further improve the accuracy and application range of pipeline leakage detection,this paper first simulates the complex water distribution system to sets up an experimental platform.In the pipe network model,the pressure measurement points and the simulated leak points are respectively arranged to simulate the leakage of the pipe network.The pressure signal is collected from it for subsequent analysis.Secondly,the collected pressure signals are processed to extract the different characteristics before and after the leakage.Based on this,a leakage detection method based on wavelet denoising,short time Fourier transform(STFT)and power spectrum is proposed,using this method can real-time monitoring of the leakage situation.This method is compared with the six methods of Empirical Mode Decomposition(EMD),wavelet decomposition,Gauss model,recurrence plot,Wigner-Ville distribution(WVD)and Wigner-Hough transformation(WHT),and the actual pipe network leakage is verified.The results show that this method can accurately diagnose the leakage of the pipeline network.Because the method is simple and easy to be popularized,it can be applied directly to the actual pipe network detection.This method is verified by gas network and heating network.It is concluded that this method is universality and is especially suitable for leak detection of complex network.Finally,using the method proposed in this paper,cRIO-9063 is selected as real-time controller based on NI CompactRIO platform,and NI-9205 is chosen as signal acquisition module.On this basis,based on the idea of modularization,the programs of FPGA,RT and Host are developed respectively.A portable leakage detection system for pipe network is configured to realize the function of real-time collection,analysis and leakage alarm of pressure data of pipe network.The system is verified by the experimental platform built in this paper.It is found that the accuracy rate is above 89.5%.It shows that the system can be used to detect the leakage ofcomplex pipe network effectively,and can be applied directly to the leakage detection of the pipe network.