肖宇.基于模糊熵和离散Fréchet距离的小电流接地系统故障选线方法[J].电测与仪表,2024,61(3):102-112. XIAO Yu.Fault line selection method for small current grounding system based on fuzzy entropy and discrete Fréchet distance[J].Electrical Measurement & Instrumentation,2024,61(3):102-112.
基于模糊熵和离散Fréchet距离的小电流接地系统故障选线方法
Fault line selection method for small current grounding system based on fuzzy entropy and discrete Fréchet distance
According to the fault characteristics of fault line and non-fault line, a method of fault line selection for small current grounding system based on fuzzy entropy and discrete Fréchet distance was proposed. First, a complete set of empirical mode decomposition (CEEMDAN) was used to decompose the transient zero-sequence current of each line, and the characteristic IMF component was selected according to kurtosis and continuous mean square error. Then, the correlation analysis of the characteristic IMF component of each line was carried out to construct a similarity characteristic matrix and determine whether it was a line fault or a bus fault. If the fault is a line fault, fuzzy information is granulated on the characteristic IMF components of each line. Then the three groups of Low, R, and Up after granulation of each line are mixed and superimposed. And calculate the discrete Fréchet distance, combined with the membership function, calculate to join the complex influence factors of fuzzy entropy, and construct a complex feature matrix. Finally, the fault selection is carried out by using the dual characteristic matrix. After a lot of simulation analysis, it is proved that the accuracy of the fault selection method is not affected by the transition resistance and fault closing angle, and the noise resistance is strong.
