Localization Method of Multiple Leaks Based on Time-Frequency Analysis and Improved Differential Evolution

When multiple leaks occur at the same time, the influence of leak acoustic wave signals is superposed in the leak acoustic wave signal, which affects the propagation and attenuation rule of the transient acoustic signal. The traditional leak localization method is impossible to effectively locate the multiple leak signals under the condition of mixed signal. Thus, a localization method of multiple leaks based on time-frequency analysis of acoustic wave and improved differential evolution is proposed. Since the decomposition model number of Variational Mode Decomposing (VMD) affects the feature extraction, the energy function is used to improve VMD (IVMD). Therefore, the decomposition model number of VMD is determined by energy function of each component. The IVMD is applied to acoustic wave analysis and processing. Additionally, the number of multiple leaks is extracted by Time-frequency Analysis (TFA). Then, the multiple leaks localization function is obtained. Differential Evolution (DE) is easy to fall into local optimum, and its convergence speed is slow in the later stage of evolution, Particle Swarm Optimization Algorithm (PSO) is used to improve the global convergence speed of DE, and the multiple leaks positions are calculated by improved differential evolution. By analyzing the acquired acoustic wave data of multiple leaks in experimental pipeline wtih acoustic sensor PCB 106B, the results show that the proposed method can accurately locate multiple leaks in pipeline, and the minimum error of leak localization is 18 m.