On-line ranging method for single-phase earth fault based on zero mode and phase mode current traveling waves

The present invention provides a zero-based mold and Sagami popular electric wave single-phase ground fault line ranging method. Test test point to a specific frequency and the amount of current zero-mode current traveling wave signal Sagami amount of current, using the waveform contrast, failure to distinguish the initial traveling wave, the reflected wave fault, the fault point transmission waveform corresponding to t1, t2, t3 time current waveform obtained after the order of the original line-wave, current mirror traveling wave current transmission line wave then the single-phase ground fault occurs in the first half of the measured lines; use the formula L calculated distance to fault test point to; if the the resulting current waveform corresponding to the initial order of the traveling wave, current wave transmission line, then the current mirror traveling wave single-phase ground fault occurs in the second half of the measured lines; use the formulas for distance to fault test point to; the present invention The method of high accuracy, easy to implement and can be applied to the actual site.