RU2536809C1 - Surov's method of control of successful automatic reclosing of main switch of line - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: invention relates to automation of electric networks and is designed for control of successful automatic reclosing (AR) of the main switch (MS) of a line. From the moment of appearance of the SC current surge, the first counting of time is started, which is equal to the delay time of actuation of the MS protection; with that, the moment of its disappearance is controlled; parameters of an emergency mode are determined by sending sounding pulses to all the wires of the line to determine all reflection points and to calculate distances to these points, and the obtained emergency parameters are compared to the normal parameters obtained in a similar way at operation of the line in the normal mode, and if at the moment of completion of the first time count the SC current does not disappear, and the parameters of the emergency mode differ from the parameters of the normal mode, then, a conclusion is made on MS deactivation and a signal is sent to prohibit its AR, from the moment of the SC current deactivation the second time counting is started, which is equal to the MS AR delay time, and the sounding pulses are constantly sent to all the wires of the line at a certain interval, the parameters of the line are determined after deactivation of the SC current and compared to the parameters of the normal mode, and if at any moment of time before completion of the second time count the parameters of the line, which are determined after the SC current deactivation, become equal to the parameters of the normal mode, a conclusion is made on SC self-elimination, determination of the parameters of the line is stopped, a prohibition signal at MS AR is picked up, and if at the moment of completion of the delay time of MS AR an operating current surge appears in the line, then, a conclusion is made on successful MS AR of the line.

EFFECT: enlargement of functional capabilities of the method by receiving the information on successful MS AR of the line.

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Description

The invention relates to the automation of electrical networks and is intended to control the successful automatic restart (AR) of the head circuit breaker (GW) of the line.

A known method of controlling the tripping and successful automatic reclosure of a sectionalizing circuit breaker in a ring network line is that, from the moment of the appearance of the first inrush of short circuit current (short circuit) on the busbars of a transformer supplying a line, a countdown equal to the response time of the sectioning circuit breaker protection is started. At the same time, the moment of switching off the first short-circuit current fault is controlled, and if the time countdown coincides with the moment of switching-off of the first short-circuit current fault, then the fact of switching off the sectioning switch is established. And then, from the moment of switching off the first inrush current, the short circuit of the reclosure time starts, the appearance of the second inrush current is controlled, and if at the end of the countdown of the reclosure time the current surge appears with a value greater than the normal operating current, but less than the short-circuit current, then

after that, the fact of tripping and successful reclosure of the sectioning switch installed in the ring network line is established [RU patent, No. 2337453C1, Kk. H02J 13/00, publ. 10/27/2008, bull. No. 30].

The disadvantage of this method is the impossibility of using it to control the successful reclosure of the HV line.

The task of the invention is to expand the functionality of the method by obtaining information about the successful reclosure of HV line.

According to the proposed method, from the moment of the appearance of a short-circuit current inrush, the first countdown starts, equal to the exposure time of the protection of the hot water supply, while the moment of its disappearance is monitored, the emergency mode parameters are determined by sending a probe pulse line to all wires to determine all reflection points and calculate the distances to these points and compare the received emergency parameters with the normal ones, obtained in a similar way when the line is operating in normal mode, and if at the time the first countdown ends If the short-circuit current disappears, and the emergency mode parameters differ from the normal mode parameters, they conclude that the hot water is turned off and a signal is issued to prohibit its automatic reclosure, from the moment the short-circuit current is disconnected, a second countdown starts, equal to the fast-current reclosure time, and to all wires the lines constantly send probing pulses with a certain frequency, determine the line parameters after switching off the short-circuit current, and compare them with the parameters of the normal mode and, if at some point in time before the end of the second time reference, the line parameters determined after switching off the short-circuit current, will become the same with the parameters of the normal mode, then make a conclusion about the self-elimination of the short-circuit, stop determining the line parameters, remove the ban signal on the automatic reclosure, and if at the end of the exposure time of the reclosure the short-circuit arrester appears in the line, conclude the successful reclosure of the HV line.

The essence of the invention is illustrated by drawings, where:

figure 1 presents a structural diagram containing elements for implementing the method;

figure 2 - diagrams of the signals at the outputs of the elements shown in figure 1 with an unstable short circuit at point 18 (see figure 1).

The circuit (see figure 1) contains: power transformer 1; input switch 2; head switch 3; short circuit current sensor (DTKZ) 4; working current sensor (DRT) 5. Elements: MEMORY 6; NOT 7; DELAY 8; SINGLE VIBRATOR 9; And 10, the information processing unit (BOI) 11, the probe pulse generator (GZI) 12, the probe pulse probe (PZI) 13. Elements: MEMORY 14; NOT 15; And 16; recording device (RU) 17; short circuit point 18.

The signal diagrams at the outputs of the elements shown in Fig. 1 with a short circuit at point 18 (see Fig. 1) have the form (see Fig. 2): 19 - at the output of element 4, 20 - at the output of element 5, 21 - at the output of element 6, 22 - at the output of element 7, 23 - at the output of element 8, 24 - at the output of element 9, 25 - at the output of element 10, 26 - at the output of element 11, 27 - at the output of element 12, 28 - the output of element 13, 29 - at the output of element 14, 30 - at the output of element 15, 31 - at the output of element 16, 32 - in RU 17.

In Fig. 2, in addition to the diagrams of the output signals of the circuit elements, also shown: t ₁ - the time of the occurrence of short circuit at point 18, t ₂ - the moment of disconnection of the short circuit current, t ₃ - the time of self-elimination of the short circuit, t ₄ - the end time of the exposure time of the reclosure of the hot water line .

The method is as follows.

In the normal mode of operation of the network, the input switch 2 and the head switch 3 are turned on, there is no short circuit in the line, so there is no signal at the DTKZ 4 output either, and the circuit is in control mode.

When a short circuit occurs, for example, at point 18, a signal will appear at the output of DTKZ 4 (Fig. 2, Diagram 19, time t ₁ ), which will be transmitted to the first input of the BOI 11, while from its first output (Fig. 2, Diag. . 26) the signal will go, which will go to the GZI 12. It will send probe pulses to all wires of the line (Fig. 2, Diagram 27), which, having reached the reflection points, will return back and go to the PZI 13 and from its output (Fig. .2, diag. 28) will be sent to BOI 11. This element will determine the emergency mode parameters of the line by determining all reflection points and calculating the distance to these nuts. Also, the output signal DTKZ 4 will go to the input of the element NOT 7, while its output signal will disappear (Fig. 2, Diagram 22), and also will go to the input of the element MEMORY 6, it will be remembered by it (Fig. 2, Diagram 21) and to the input of the element DELAY 8. From the output of this element, the signal appears after the exposure time of the protection of the GV 3 (Fig. 2, Diagram 23) and goes to the input of the SINGLE-VIBRATOR 9. It will produce one oscillation (Fig. 2, Diagram 24), this signal "discards" the memory from element 6 (figure 2, Fig. 21) and will go to the first input of element And 10. At this point in time, the GW 3 will turn off, the short-circuit current will disappear (Fig. 2, Diagram 19, time t ₂ ) and the signal (Fig. 2, Diagram 22) will again appear at the output of the HE 7 element, which will go to the second input of And 10. It will work (Fig. 2, diag. 25), its output signal will go to the second input of the BOI 11, and a signal will appear on its third output, which will go to the input of the element MEMORY 14, it will be remembered by it (Fig. 2, diag. 29) 3, will provide a ban on its AR. Also, BOI 11 will provide a constant sending of probe pulses, with a certain periodicity, to the line wires to determine its parameters until the self-elimination of the fault, if this happens, or until the end of the exposure time of the automatic recirculation gun GV 3, if the fault is not eliminated. And if the calculated parameters of the line at some point in time become the same with the normal parameters, for example, at time t ₃ , then at the second output of the BOI 11 a signal will appear (Fig. 2, Diagram 26), which will be fed to the input of the SINGLE-VIBRATOR 15 element . He will make one oscillation (figure 2, diag. 30) and with this signal “discard” the memory from element 14 (figure 2, diag. 29), while the prohibition of automatic reclosure GW 3 will be lifted. Also, the output of the SINGLE-VIBRATOR 15 will be supplied to the first input of the And 16 element. After the exposure time of the reclosure, the GV 3 will turn on, a signal will appear at the output of the DRT 5 (Fig. 2, Diagram 20), which will go to the second input of the And 16 element. It will work ( Fig. 2, Diagram 31), its signal will arrive at RU 21 and there will appear information that the short circuit has removed itself and the GV 3 has successfully turned on (Fig. 2, Diagram 32).

Thus, when using the proposed method, it is possible to obtain information about the successful reclosure of the HV line.

Claims (1)

A method for monitoring the successful automatic restart (AR) of the line circuit breaker (GW), which consists in fixing the inrush current short circuits and in measuring the time between them, characterized in that from the moment the inrush current appears, the first time count starts, equal to the exposure time of the protection while controlling the moment of its disappearance, determining the emergency mode parameters by sending a probe pulse line to all the wires to determine all reflection points and calculate the distances to these points and comparing The received emergency parameters are compared with the normal ones, obtained in a similar way when the line was operating in normal mode, and if at the end of the first countdown the short-circuit current disappears, and the emergency mode parameters differ from the normal mode parameters, they conclude that the hot water is turned off and sends a signal to the prohibition of its automatic reclosure, from the moment of switching off the short-circuit current, a second countdown starts, equal to the exposure time of the automatic reclosure, and probe pulses are constantly sent to all wires of the line with a certain frequency, the parameter is determined the lines after switching off the short-circuit current and comparing them with the parameters of the normal mode, and if at some point in time before the end of the second countdown the line parameters determined after switching off the short-circuit current become the same as the parameters of the normal mode, they conclude that the short circuit they cease to determine the parameters of the line, they remove the prohibition signal for the reclosure of hot water, and if at the end of the exposure time of the reclosure of the hot water the inrush current appears in the line, then they conclude that the automatic reclosure of the hot water line is successful.

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