FREQUENCY-PHASE RELAY Russian patent published in 2004 - IPC

FIELD: electrical engineering.

SUBSTANCE: proposed frequency-phase relay can be utilized in the capacity of frequency-phase difference relay controlling frequency and phase of voltage of generator with reference to frequency and phase of network voltage. Frequency-phase relay has three actuators, four comparators, three AND gates, two formers of short pulses of leading edge, two frequency meters, two amplitude meters, multiplier, divider, multiplier of constant coefficient, algebraic adder, two inverters. Meters of frequency of network and generator convert signals of network and generator in correspondence with mathematical expressions U₀=A₀/f₀, U₁=A₁/f₁, where U₀ is signal across output of network frequency meter; U₁ is signal across output of generator frequency meter; f₀ is network frequency; f₁ is generator frequency; A₀,A₁ are scale coefficients proportional to amplitudes of voltages of network and generator. Meters of amplitudes of network and generator convert signals of network and generator to values proportional to their amplitudes and equal to coefficients A₀ and A₁ correspondingly. Duration of pulses formed by first and second formers of short pulses of leading edge is proportional to permissible value of mismatch of phases of voltages of network and generator and duration of pulses formed by pulse stretcher is less than period of voltage of generator and period of voltage of network.

EFFECT: expanded functional potential of frequency-phase relay by control over frequency and phase of voltage of generator with reference to frequency and phase of voltage of network.

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