METHOD OF REMOTE DETERMINATION OF SINGLE PHASE-TO-GROUND-FAULT LOCATION Russian patent published in 2017 - IPC G01R31/08 

FIELD: electricity.

SUBSTANCE: invention can be used for remote determination of the single phase-to-ground-fault location (SEF) on ETL under operating voltage in 6-35 kV power distribution networks operating with an isolated neutral, compensating for capacitive currents or grounding the neutral through a high-ohm resistor having a radial structure. The essence of the claimed method lies in the fact that in the method of remote determination of the single phase-to-ground-fault location by unilateral measurement of the transient voltage u(t) on the damaged phase on the buses of the monitored object and the zero sequence residual current 3i₀(t) of the damaged line, the rate of change of the transition current is additionally recorded, all the moments t_0k of current transitions 3i₀(t) through the zero value are stored, where k is the ordinal number of the current transition through the zero value. Determine and store the corresponding time t_0k instantaneous values of the voltage on the damaged phase u(t_0k), the rate of change of the current , and then over the stored values of the voltage on the damaged phase u(t_0k), the rate of current change and the reference value of the running inductance for the damaged line Ld determine the distance l_f up to the single phase-to-ground-fault location in accordance with the expression . In this case, in the presence of several transitions of the zero-sequence current of the faulted line through the zero value, the distance to the single phase-to-ground-fault location is defined as the average of several values of l_vk.

EFFECT: increasing the accuracy of the method of determining the distance to the single phase-to-ground-fault location on the power line.

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