METHOD AND DEVICE FOR PROTECTING POWER DISTRIBUTION NETWORKS AGAINST ARCING SHORT CIRCUITS

摘要

FIELD: insulated-neutral alternating-current low-voltage power distribution networks and two-wire direct-current networks. ^ SUBSTANCE: proposed method includes current (voltage) and insulation resistance measurements, comparison of measured values with relay settings tuned away from normal transient conditions of equipment under protection, and operation of final element in case measured values exceed setting ones; relay operating current (voltage) settings are tuned away from continuous admissible conditions provided ground-fault or current (voltage) relays operate simultaneously or sequentially one after another but within selective time delay of protective gear. Two design alternated of device implementing this method are also proposed. ^ EFFECT: enhanced response to arcing short circuits. ^ 4 cl, 2 dwg