FREQUENCY RELAY Russian patent published in 2005 - IPC

FIELD: electrical engineering; electronic frequency relays.

SUBSTANCE: proposed frequency relay that can function both as frequency step-up and frequency step-down relay and does not respond to short-time failure of frequency under control has frequency-dependent component, rectifier, four threshold units, three AND gates, counter, reversing counter, final member, clock generator, pulse frequency divider, monostable multivibrator, pulse shaper, and OR gate; pulse shaper is designed to generate pulses at negative signal drop across its input; monostable multivibrator input functions as frequency-relay trigger input; frequency-dependent component has amplitude-frequency response with its first maximum corresponding to minimal admissible value of f_d (deviation of controlled frequency from rated value), second maximum corresponding to maximal admissible value of f_d+ (deviation of controlled frequency from rated value), and with its second maximum that corresponds to f_r (rated value of controlled frequency) and is disposed between first and second minimums.

EFFECT: enlarged functional capabilities and reduced noise immunity.

1 cl, 3 dwg