METHOD OF DIAGNOSTICS AND DIRECTED PROTECTION AGAINST SINGLE-PHASE SHORT CIRCUITS IN ELECTRICAL NETWORKS Russian patent published in 2010 - IPC H02H3/16 

FIELD: electricity.

SUBSTANCE: method consists in measurement of instantaneous current values of zero-sequence and rate of rise of instantaneous zero-sequence voltage values of transient process during failure of the network phase to ground, calculation of integral value calculated at the time interval of protection actuation, supply of command action on operating protection elements when the integral value exceeds the specified value, as integral value there chosen is mutual correlation function of sets of instantaneous zero-sequence current values and rate of rise of zero-sequence voltage, and insulation state is checked at not stable single-phase short circuits to ground as per the number of insulation damages recorded when the integral value exceeds the specified value.

EFFECT: improving reliability and enlarging functional capabilities.

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