Single-Phase-to-Ground Fault Location in Active Distribution Networks Based on Transient Feature Extraction and Topological Constraints

Abstract

To address the issue of ambiguous fault localization in multi-branch active distribution networks (ADN) caused by the weak characteristics of single-phase high impedance faults (HIF) and interference from distributed generation (DG), a fault section location method integrating multi-source transient features and topological constraints is proposed. Relative entropy and wavelet transform are utilized to extract the features of voltage distortion and high-frequency current energy, respectively. An improved Dempster-Shafer (D-S) evidence fusion mechanism based on energy gating is proposed to effectively filter out false belief interference induced by voltage dispersion and DG back feeding. Finally, a branch adjacency difference matrix is constructed to pinpoint the target section utilizing abrupt changes in belief. Simulation results demonstrate that the proposed method maintains high reliability under conditions of a $3000 \Omega$ high fault impedance, -1 dB strong noise, and DG frequency-domain fluctuations.