METHOD FOR REMOTE DETERMINATION OF THE PHASE-TO-GROUND CLOSURE POINT Russian patent published in 2019 - IPC G01R31/08 

FIELD: electric power engineering.

SUBSTANCE: invention relates to electric power engineering and can be used for remote determination of phase short-circuit to ground at power line under operating voltage. In the method for remote determination of phase closing point to ground, moments t_0k transitions of zero sequence current 3i₀(t) through a zero value, where k is sequence number of current passing through zero value, injured phase is determined, determined corresponding to time t_0k instantaneous values of voltage on damaged phase u(t_0k), determining distance l_s to point of phase closure to ground in accordance with expression where d3i₀(t_0k)/dt is derivative of zero sequence current corresponding to moment of time t_0k, L_d is the linear inductance of the damaged line, wherein in the presence of several transitions of zero sequence current of the damaged line through the zero value, the distance to the single-phase ground fault location is determined as the average of several values, each phase of the line is equipped with a digital transformer equipped with a resistive or resistive-capacitive voltage divider, a Rogowski belt and a DC sensor, phase voltages u_A(t), u_B(t), u_C(t) on buses of the monitored object are determined using resistive or resistive-capacitive voltage dividers, phase currents of line i_A(t), i_B(t), i_C(t) is determined using direct current sensors, zero-sequence current is calculated from DC sensors by summation 3i₀(t)=i_A(t)+i_B(t)+i_C(t), and phase current derivatives of di_A(t)/dt, di_B(t)/dt, di_C(t)/dt is determined using Rogowski's belts, the zero-sequence current derivative corresponding to the time moment t_0k, is determined by addition d3i₀(t_0k)/dt=di_A(t_0k)/dt+di_B(t_0k)/dt+di_C(t_0k)/dt.

EFFECT: technical result consists in improvement of accuracy of remote determination of phase-to-earth short-circuiting at power transmission lines under operating voltage.

1 cl, 1 dwg