DIFFERENTIAL-FREQUENCY RELAY Russian patent published in 2004 - IPC

FIELD: electrical engineering; synchronized generator frequency control. SUBSTANCE: differential-frequency relay has two clippers, four AND gates, two frequency period meters, multiplier, two comparators, two final elements, two short pulse shapers, clock generator, delay circuit, flip-flop, algebraic adder, and monostable multivibrator. Proposed relay is designed so that it does not respond to transients during ON- operation nor to relative error in input and synchronized signal frequencies. EFFECT: enhanced precision, enlarged functional capabilities. 2 cl, 2 dwg