Small current distribution network fault line selection method based on correlation analysis of the transient fault signal

The present invention is a small current earth fault line selection method based on correlation analysis of transient fault signals, belonging to the field distribution automation. The technical problem to be solved by the fault in distribution system is single-phase ground; technical features of the present invention exhibit the three-phase current feed line is introduced, and obtains the pieces of two-phase current differential feeder, the feeder and the zero sequence current respective two-phase current differential correlation analysis, the correlation matrix to form a comprehensive E; E is selected and p max ρmin, if yes ρmax-ρmin≥ρset, it is determined that the system is single-phase ground fault occurs, the fault line and the corresponding feeder of p max ; if ρmax-ρmin & lt; ρset, it is determined that there is a single-phase ground failure at the busbar. The present invention is applicable to Patent 35kV and 10kV voltage level, non-effectively grounded neutral line - hybrid cable distribution network, the method having a real-time, adaptability, the characteristics of high accuracy, great practical value.