RESISTANCE RELAY Russian patent published in 1999 - IPC

FIELD: relay protection; fast- response protective gear for power transmission lines. SUBSTANCE: relay provides for monitoring insulation resistance of power transmission line within half-cycle of commercial frequency with operating characteristic in complex plane in the form of circle, ellipse, arcs, etc. depending for its operation on comparison of phase angle between voltage and current of particular line with binary number arriving from microcomputer. This is attained due to introducing following additional components in relay: four voltage amplifiers, six differential amplifiers, two differential phase-shifting amplifiers, eight comparators, six switches, two 2AND gates, pulse generator, two control pulse shapers, two delay circuits, two binary counters, two storage registers, two digital comparators, and 2OR gate. EFFECT: improved speed of response, accuracy, and noise immunity. 2 dwg