FREQUENCY RELAY Russian patent published in 2004 - IPC

FIELD: electrical engineering.

SUBSTANCE: given frequency relay incorporates isolation transformer, frequency filter, two pulse formers, two formers of short pulses by difference of input voltage, five AND gates, frequency-dependent element, two NOT gates, two actuating elements, two pulse stretchers. Frequency-dependent element is intended to form signal which amplitude decreases proportionally to value of modulus of deviation of frequency of input voltage from nominal and phase changes proportionally to value and sign of deviation of frequency of input voltage from nominal.

EFFECT: expanded functional capabilities of frequency relay.

2 dwg