FIELD: electricity.
SUBSTANCE: invention deals with techniques for registration of transient fault to ground in electric power distribution networks. The invention concept is as follows: the invention effect is based on estimating voltage zero sequence (U0) and summation current (Isum) of phase currents. The voltage zero sequence and summation current become filtered so that the voltage zero sequence and summation current to have undergone filtration should be represented solely by the transient phenomena component generated under transient (intermittent) fault to ground conditions. When the amplitudes (A(U0), A(Isum)) of the voltage zero sequence (U0) and summation current (Isum) transient phenomena component exceed the relevant preset amplitude values (A(U0limit), (A(Isumlimit)) with the value of the phase difference between the phase angles (φ(U0), φ(Isum)) of the above voltage zero sequence (U0) and summation current (Isum) transient phenomena component remaining within a pre-specified range the fact is established of a transient (intermittent) fault to ground having occurred within the electric power distribution network under observance. Depending on the phase difference value one ascertains whether the transient (intermittent) fault to ground has occurred within the feeder under observance or within any other feeder of the galvanically connected electric power distribution network.
EFFECT: enhanced reliability of fault registration.
22 cl, 23 dwg
Authors
Dates
2009-06-10—Published
2004-10-21—Filed