Single-Phase Ground Fault Line Selection Algorithm in Distribution Network Based on Multi-layer Wavelet Decomposition Coefficients to Construct Eigenvalues

Traditional fault line selection methods using steady-state quantities require a relatively long time, while methods using transient quantities, although quick in judgment, are prone to interference or misjudgment. To address these issues, this paper proposes a method for fault line determination using the transient characteristics of zero-sequence current. Firstly, the zero-sequence characteristics after a single-phase ground fault in the distribution network are analyzed. Secondly, the wavelet transform coefficients of the zero-sequence current on the line are extracted using Discrete Wavelet Transform (DWT), and a fault line selection criterion is established by constructing a feature quantity that characterizes different fault lines. Finally, the simulation data of the single-phase ground fault model of the distribution network verifies the effectiveness of the proposed fault line selection method.