Fault Ranging Method for Overhead-Cable Hybrid Distribution Lines Based on CEEDMAN Energy Relative Entropy

Abstract

Abstract According to the parameter characteristics of cable-overhead line and the folding and reflection process of traveling waves when the wave impedance is discontinuous, a traveling wave abrupt change extraction method based on the empirical mode decomposition of fully adaptive noise ensemble (CEEDMAN) energy relative entropy is proposed for the first time. Through the combination of CEEDMAN and energy relative entropy, the transient traveling wave signals are generated when reflection and refraction occur, and the energy value of traveling waves will change abruptly, and the reflected and refracted wave heads will be captured by the change of relative energy. Combined with the magnitude difference of zero sequence current, the fault area can be determined. Traveling waves have different wave speeds in overhead lines and cable lines, and fault ranging is performed by determining the corresponding propagation speed. Finally, simulation verifies that the method can accurately determine the fault zone with high ranging accuracy under the conditions of different fault locations, different transition resistances and different initial phase angles.