SU989652A1 - Starting device for interlocking relay protection at swinging - Google Patents

Description

The invention relates to electrical engineering and can be used in relay protection devices, in particular in the remote protection of AC power lines.

There are known devices and algorithms for starting blocks for blocking relay protection during oscillations, based on the determination of the emergency component of the monitored electric quantity l, 2 and 3.

The closest in technical essence is a device containing a filter of symmetrical components, connected to the input converters, and an output through a low-pass filter to the input of one of two consecutively connected identical blocks, each of which contains a delay element and an adder, the first input of the adder is directly, and the second through the delay unit is connected to the input of an identical block, the module driver connected by the input to the output of the second identical block, and the output directly and black of static unbalance compensation element to the inputs responsive body. In the device, cascaded with identical blocks, the emergency component is extracted from the monitored signal. The unbalance at the output of the second identical block is determined by the ratio. by

To U;

Inv, T Shi

10 "nb

- s1mplitud unbalance;

m и - amplitude controlled

gp

signal.

 nominal frequency of the power system h.

15

In the frequency range of the power system 50 + 5 Hz, the maximum unbalance value reaches 0.12, from the amplitude of the monitored signal, which requires a corresponding coarseness of the triggering organ.

The aim of the invention is to increase the sensitivity of the triggering organ.

The goal is achieved by

25 then to the starting blocking device of the protection of the swing protection, containing input transducers connected by outputs to the filter inputs of the symmetrical components, at the output

Claims (3)

30 of which is included a low-pass filter and two series-connected blinkers connected by an output to one input of an adder, to another input of which is connected an output of a low-pass filter, a module driver connected by an input to an output of an adder, and an output directly to one input and through the element (compensation static unbalance to another input of the reacting body, a scale converter is inserted, connected by an input to the output of one of the delay blocks, and output to a third input of the said adder. A diagram shows the functional of the start-up blocking device of the roll-over protection during oscillations.The device contains input converters 1, 2 and 3 connected by outputs to the inputs of the filter of symmetrical components 4, low ix filter 5 frequencies delay blocks 6 and 7 large-scale converter 8, adder driver module 10, an element of compensation of static unbalance 11 and a reacting element 12. The device works as follows. The signal from the output of the filter of symmetrical components 4, which converts the phase values from the transducer outputs s 1, 2 and 3, is input to a lowpass filter 5, where the high frequency harmonics are filtered out. In the adder 9, the monitored signal received from the output of the low-pass filter 5 is summed with the signal shifted in time by the delay block b and the amplitude-converted scale converter 8 and the signal shifted in time by the delay blocks 6 and 7. Voltage amplitude unbalance at the output of the adder 9, depending on the signal obtained from the output of the low-pass filter 5 and, is determined by the relation +, where k is the conversion factor of the scaling transformer; C is the delay time of each of blocks 6 and 7. By selecting the coefficient k and time f, you can change the frequency range, © in which the unbalance voltage does not exceed the allowable value, or the unbalance value in a given frequency range. In particular, in the frequency range of 50 + 5 Hz, it is possible to finish off the maximum unbalance value, not exceeding 0.01 of the amplitude of the monitored signal. During a short circuit in the power system, there is an abrupt change in the monitored signal and at the output of adder 9 a signal appears unbalanced during the transient process in delay blocks b and 7, which is converted into a unipolar signal by the shaper module 10 and leads to the response of the reacting organ 12, Introduction large-scale converter and the corresponding connection of blocks reduces the unbalance voltage due to the frequency disconnection of the power system from the nominal one, as a result of which the sensitivity increases Starting bodies. Claims of the Inverter Relay Protection Interlock Body, comprising input converters connected by outputs to the inputs of a symmetric filter, the output of which includes a low-pass filter and two series-connected delay blocks connected by an output to one input of an adder, the other input of which is connected the output of the low-pass filter, the module driver connected by the input to the output of the adder, and the output directly to the same input and through the static compensation element ance to another reactant entry body, characterized in that tselyyu increasing sensitivity, it entered the scale converter connected to the input output of one of delay units, and output to the third input of said adder. Sources of information taken into account in the examination 1. USSR author's certificate number 437143, cl. H 02 H 11/00, 1972. 2. Fedorov E.N., Ginsserson E.M. Starting organs of interlocking relay protections in case of increased sensitivity. - Electric stations, 1977, 7. 3. Gelfand Ya. S., Zisman L. S. Using high-speed computers to perform relay protection functions. Collection of reports at the All-Union Scientific and Technical Meeting on relay protection and automation of power systems, Moscow, Istra, 1975, p. 173176. H fVi t.E