PHASE-FREQUENCY RELAY Russian patent published in 2005 - IPC

FIELD: electrical engineering; electronic relays for adjusting phase and frequency of generator connected to supply mains.

SUBSTANCE: proposed relay that incorporates provision for adjusting generator phase and frequency to those of supply mains at a time and for generator protection against short-time frequency failure has frequency-dependent component, two adders, two final elements, eleven threshold units, five AND gates, two reversing counters, clock generator, pulse frequency divider, monostable multivibrator, and short pulse shaper; input of frequency-dependent component functions as generator voltage input; monostable multivibrator input functions as trigger input of phase-frequency relay; in addition first and second final components are made in the form of tenth and eleventh threshold units, respectively, whose inputs and outputs function as those of respective final components; frequency-dependent component affords phase shift of input signal in proportion to its frequency deviation from normal corresponding to supply mains frequency.

EFFECT: enlarged functional capabilities, enhanced noise immunity.

1 cl, 2 dwg