RU2551385C1 - Control method of double false tripping of master circuit breaker in line of ring network - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: in case of voltage and operating current failure and surge of short-circuit current is unavailable in the line of the main power supply source countdown of delay time is started for automatic reclosure of the master circuit breaker (MCB), at that voltage occurrence and surge of operating current are monitored and if they occur at the moment of delay time ending and disappear upon completion of the delay time for MCB actuation, then conclusion is made about double false tripping of MCB in the line of ring network. The suggested method allows receiving information on double false tripping of the MCB in the line of ring network.

EFFECT: expanding functionality by receipt of information on double false tripping of the MCB in the line of ring network.

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Description

The invention relates to the automation of electrical networks and is intended to control double false tripping of the head switch (GV) line of the ring network.

There is a method of controlling the false shutdown of the sectionalizing circuit breaker in the ring network line, which consists in the fact that at the moment of detecting the drop in the operating current at the beginning of the main power supply line to a value determined by the load of the line connected after the sectioning circuit breaker and the absence of an inrush short-circuit current, the countdown begins equal to the holding time of the switch of the automatic reserve enable point (AR). At the end of the countdown of this time, the occurrence of a current surge at the beginning of the backup power supply line is controlled and, if a current surge occurs with a value determined by the disconnected load of the main power supply line, then the fact of a false disconnection of the sectioning switch in the ring network line is established [Patent RU No. 2378754, publ. . 10/10/2010, bull. No. 1].

The disadvantage of this method is the impossibility of using it to control double false shutdown of the hot water line of the ring network.

The objective of the invention is to expand the functionality of the method by obtaining information about the double false disconnection of the GW line of the ring network.

According to the proposed method, from the moment of the disappearance of voltage, operating current and the absence of an inrush current of the short circuit in the main power supply line, the exposure time of the automatic reclosure HV is started, while the occurrence of the voltage and inrush of the operating current are controlled and, if they appear at the end of the counted time, and after Since the end of the shutter speed of the protection of the hot water with acceleration disappear, then they conclude about a double false shutdown of the hot water supply of the ring network.

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 (see figure 1).

The circuit (see Fig. 1) contains: power transformers 1 and 2, input switches 3 and 4, head switches (GW) 6 and 7, sectionalizing switches 8 and 9, switches 5 and 10 bus and network, respectively, points for automatically switching on reserves, working current sensor (DRT) 11, short circuit current sensor (DTKZ) 12, voltage sensor (DN) 13, elements: NOT 14, 15 and 16; And 17, 21, and 25; MEMORY 18 and 22; DELAY 19 and 23; SINGLE-VIBRATOR 20 and 24: recording device (RU) 26.

The signal diagrams at the outputs of the elements shown in figure 1, have the form (see figure 2): 27 - at the output of element 11; 28 - at the output of element 12; 29 - at the output of element 13; 30 - at the output of element 14; 31 - at the output of element 14; 32 - at the output of element 16; 33 - at the output of element 17; 34 - at the output of element 18; 35 - at the output of element 19; 36 - at the output of element 20; 37 - at the output of element 21; 38 - at the output of element 22; 39 - at the output of element 23; 40 - at the output of element 24; 41 - at the output of element 25; 42 - in RU 26.

In addition to the diagrams of the output signals, figure 2 also shows: t ₁ - the time of the disappearance of voltage and operating current; t ₂ - the moment of the end of the exposure time of the automatic recirculation unit ГВ 6; t ₃ - the end of the exposure time of the protection of the GV 6 with acceleration.

The method is as follows.

In normal mode, the operation of the ring network switches 3, 4, 6, 7, 8 and 9 are on, and switches 5 and 10 are off. There is no signal at the output of DTKZ 12 (Fig. 2, Diagram 28), because no short circuit current. There are signals at the outputs of DRT 11 and DN 13 (Fig. 2, diagrams 27 and 29, respectively), and there are no signals at the outputs of elements NOT 14 and 16, so AND 17 will not work and the circuit is in control mode.

When the voltage and operating current disappear, for example, at time t ₁ , caused by a false shutdown of the GV 6, signals will appear at the outputs of elements NOT 14 and 16 (Fig. 2, diag. 30 and 32), which will arrive at the first and third inputs of element And 17 At the same time, a signal will already exist at the second input from the element NOT 15, so AND 17 will work, its output signal will appear (Fig. 2, Diagram 33), which will go to RU 26, and there will appear information that the switch 6 has turned off . He also goes to the input of the element MEMORY 18. This signal will be remembered by him (Fig. 2, Diagram 34) and will go to the input of the element DELAY 19. From the output of this element, the signal will appear after the exposure time of the reclosure HV 6 (Fig. 2, Diagram 35 , time t ₂ ) and will go to the input of the SINGLE-VIBRATOR element 20. It will produce one oscillation (Fig. 2, Diagram 36), its signal will "erase" the memory from element 18 (Fig. 2, Diagram 34) and will go to the third input aND gate 21. at this point in time (t ₂₎ HS 6 turns on, the voltage in the line will be inrush current and working, so the TSR exits 11 and NAM 13 reappear signals I (2, Diagr. 27 and 29). These signals will go to the first and second inputs of the element And 21 and it will work. Its output signal will appear (Fig. 2, Diagram 37), which will go to RU 26, and there will appear information about the automatic recirculation device ГВ 6, and it will also go to the input of the MEMORY 22 element, where it will be remembered (Fig. 2, Diagram 38) and will go to the input of the element, from the output of this element, the signal will appear after the shutter speed of the protection of the GV 6 with acceleration (Fig. 2, Diagram 39). SINGLE-VIBRATOR 24. It will produce one oscillation (Fig. 2, Diagram 40), this signal reset "memory element 22 (Figure 2 Diagram. 38), and goes to the third input of aND gate 25. at this point in time (t ₃₎ HS 6 falsely turned off due kakoy- For failure or malfunction of the automation system. In this case, the voltage and operating current disappear in the line, therefore, the signals disappear from the outputs of the DRT 11 and DN 13 (Fig. 2, Diagram 27 and 29), and the output signals appear on the elements NOT 14 and 16 (Fig. 2, Diagram 32 and 34), which will go to the first and second inputs of the And 25 element. It will work (Fig. 2, Diagram 41), its output signal will go to RU 26 and there will appear information that GV 6 has repeatedly fallen off (Fig. 2, diag. 42).

Thus, the proposed method allows to obtain information about the double false shutdown of the hot water line of the ring network.

Claims (1)

A method for monitoring double false shutdown of the main switch (GV) of the ring network line, which consists in fixing the inrush currents and in measuring the time between them, characterized in that from the moment the voltage, operating current and the absence of inrush current of the short circuit in the main power supply line begin to count the exposure time of the automatic restart of the hot water, while controlling the appearance of voltage and surge operating current and, if they appear at the end of the counting time, and after the end of If the exposure delay of the hot water protection with acceleration disappears, then they conclude about a double false disconnection of the hot water supply of the ring network.

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