Leakage Detection and Location Method of Single Measuring Point of Water Supply Pipeline Based on Improved Variational Mode Decomposition

In order to overcome the problem that the traditional negative pressure wave technology can only detect and locate the leakage in the pipe segment between two sensors, the compression wave and fluid wave are introduced into the detection and location process. At the same time, in order to improve the accuracy of leak location, a method of calculating the initial leak time based on variational mode decomposition and Teager energy operator was proposed. Firstly, VMD was used to decompose the measured signals into multiple IMFs. Then the IMF and reference signals were cross-correlated and the mean square error was calculated to establish the objective function. Secondly, the threshold was set to eliminate most of the noise, and the modal component corresponding to the signal after the initial denoising was reconstructed. Finally realize signal noise reduction. In order to verify the effectiveness of the proposed method, the leakage conditions of pipelines with different materials were simulated. The simulation results show that the proposed method has less error in calculating the initial leakage time and higher accuracy in locating the leakage point. The relative error of PVC pipe leakage location is 0.49%, the relative error of steel pipe leakage location is 0.14%.