Regionalized fault line in distribution networks based on an improved SSA-VMD and multi-scale fuzzy entropy

To solve the insufficient utilization of transient power frequency current components when single-phase grounding fault occurs in high-voltage grounding system, a ground fault routing method based on improved sparrow search algorithm optimized variational modal decomposition (ISSA-VMD) and multi-scale fuzzy entropy (MFE) is proposed. First, the elite opposition-based learning strategy (EOBLS) is used to improve the population diversity of the SSA and adopt the improved SSA to optimize VMD's parameters. From the experimental data, we can know the optimized variational mode decomposition can accurately distinguish the power frequency components of each feeder transient zero-sequence current. Second, calculate the MFE value of the power frequency component of the zero-sequence current of each feeder and select the multi-scale fuzzy entropy partial mean (PMMFE) as the line selection criterion, and then, the fault line is selected. MATLAB/Simulink simulation experimental results and the experimental results of a real experimental field for a 10-kV distribution network show that this proposed method can select the right line under most mistake conditions, with high reliability and strong robustness.