METHOD FOR LOCATING SINGLE-PHASE GROUND FAULT IN POWER DISTRIBUTION NETWORK Russian patent published in 2000 - IPC

FIELD: power engineering; determining origination of transient process in case of ground fault. SUBSTANCE: transient current and voltage signals are filtered off. Transient time is measured. Transient waveform frequency under ground fault conditions is evaluated. Low frequencies of measured transient current and voltage signals are filtered off. Transient voltage and current spectra U(ω), and I(ω) and impedance spectrum are calculated. Distance to ground fault is evaluated for digital angular frequency w_sh. Faulty-phase voltage and current signals are filtered off by means of comb filter. Measured voltage and current signals are filtered off in two directions, charge/discharge transient frequency is estimated using transient autocorrelation function, and complex spectra of transient voltage and current are calculated using parametric methods for spectrum evaluation. Impact of noise is reduced by decomposing singular value of data array using only data acquired in transients during charge/discharge process. EFFECT: improved accuracy. 3 cl, 9 dwg