Line method for detecting high resistance ground fault distribution line

The present invention discloses a method of detecting line distribution line high resistance ground fault, the zero sequence voltage waveform in the 2 to 3 cycles measured after high-resistance ground fault, which contains a harmonic spectrum in the high impedance earthed line fault detection information can be used for high impedance earth fault belongs to the field of power system protection and control. This method of collecting the secondary side of the transformer feeder zero sequence voltage harmonics, wherein the fault determining circuit topology according to the harmonic frequencies (typically between 1000 ~ 5000Hz), by detecting the harmonic amplitude and frequency, it is determined whether there has been a high line resistance ground fault. This method is particularly suitable for small current below 10kV and grounding system, only a single acquisition zero sequence voltage signal is analyzed. Compared with the conventional method of determining information collection more convenient, more sensitive, and effective operating conditions different from other types of fault, malfunction and reducing Refuse, more accurate identification.