RU2474029C1 - Method to monitor failure of disconnection of sectionalising circuit breaker and disconnection of head circuit breaker of main power supply source line, connection and failure of disconnection of circuit breaker of network station of automatic load transfer and disconnection of sectionalising circuit breaker of reserve power supply source line in circular network - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: from the moment the first short-circuit current surge appears on buses of the main power supply source, simultaneously they start counting time of delay for protection actuation in sectionalising (SCB) and head (HCB) circuit breakers of the line of the main source of power supply, at the same time they monitor the moment of short circuit current disconnection, and if at the moment of SCB delay time ending the short circuit current does not switch off, but it switched off at the moment of HCB delay time ending, the conclusion is made on failure of SCB disconnection and HCB disconnection, from the moment of disconnection of the first short circuit current surge they start counting time of delay for connection of a circuit breaker of a network station of ALT (NSCB ALT), and at the moment of count stop at the buses of the reserve power supply source transformer they monitor appearance of the second surge of short circuit current, and if it appears, then the conclusion is made on connection of this circuit breaker to short circuit, from the moment the second surge of short circuit current appears, they simultaneously start counting time of delay of protection actuation with acceleration of NSCB ALT and time of delay of protection actuation of SCB in the line of the reserve power supply source, and if the second surge of short circuit current switches off at the moment of ending of not the first specified time, but the second time, the conclusion is made on the failure of NSCB ALT disconnection and disconnection of SCB in the line of the reserve source of supply.

EFFECT: expansion of functional capabilities.

Description

The invention relates to the automation of electrical networks and is intended to control the failure of disconnecting the sectioning and turning off the main circuit breaker (GV) of the main power supply line, turning on and off the circuit breaker of the main automatic transfer switch (ATS) circuit breaker and disconnecting the sectioning switch (CB) of the backup power supply line ring network.

There is a method of controlling the shutdown of the hot water line in case of failure to disconnect the CB when it is turned on again for a stable short circuit (short circuit) in the ring network powered by the buses of the two-transformer substation, which consists in fixing the inrush currents of the short circuit and in measuring the time between them. Why, from the moment of the appearance of the first short-circuit current inrush on the busbars of the transformer supplying the line, a countdown is started equal to the response time of the CB protection, while the moment of disconnection of the first short-circuit current is monitored. And if the moment of the end of the countdown coincides with the moment of disconnection of the first inrush current short circuit, then at the beginning the fact of disconnecting the CB is established. Then, from the moment of switching off the first short-circuit current fault, the countdown of the total time equal to the time delay of the automatic reclosure of this switch and the response time of its protection with acceleration are started, while the appearance of the second short-circuit current fault is controlled. From the moment of the appearance of the second short-circuit current fault, the start-up time of the short-circuit protection starts, and if, after its appearance at the end of the countdown of the total time, the second short-circuit current break does not turn off, then the fact of failure to turn off the CB again is established, and if the moment of the end of the countdown GV coincides with the moment of disconnection of the second short-circuit current inrush, then establish the fact of disconnecting the GV line in case of failure to disconnect the ST when it is again turned off to a stable short-circuit in the ring network [RF patent No. 2394331, publ. 07/10/2010, bull. No. 19].

A disadvantage of the known method is the impossibility of using it to control the failure of disconnecting the sectioning and disconnecting the main circuit breakers of the main power supply line, turning on and off the circuit breaker of the ATS network point switch and disconnecting the CB lines of the backup power source in the ring network.

The objective of the invention is to expand the functionality of the method by obtaining information about the failure of disconnecting the sectioning and disconnecting the head switches of the main power supply line, turning on and failure to turn off the circuit breaker of the ATS network point and disconnecting the CB line of the backup power source in the ring network.

According to the proposed method, from the moment of the appearance of the first short-circuit current surge on the tires of the main power supply, the protection delay time of the sectioning and head circuit breakers of the main power supply line simultaneously starts to monitor the time of the short-circuit current deviation, and if at the end of the protection protection delay time the current Short circuit did not disconnect, but disconnected at the end of the exposure time of the protection of the hot water supply, then they conclude that the sectioning failure and the main about the circuit breakers of the main power supply line, from the moment of switching off the first inrush current short circuit, they begin the countdown of the shutdown time of the circuit breaker of the ABP network item and at the end of the countdown of this time on the busbars of the transformer of the backup power supply they control the appearance of the second inrush current short circuit, and if it appears, then conclude that this switch is turned on in the short circuit, from the moment the second inrush current appears, the short circuit simultaneously starts the countdown of the protection operation delay with the acceleration of the switch of the network point A BP and the response time of the protection of the CB line of the backup power source, and if, at the end of the exposure time of the protection with the acceleration of the circuit breaker of the ABP, the second short-circuit current did not turn off, but turned off at the end of the protection time of the protection C of the backup power line , then make a conclusion about the failure of disconnecting the circuit breaker of the ABP network item and disconnecting the CB line of the backup power source.

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 a stable short circuit at point 4 (see figure 1).

The circuit (see Fig. 1) contains: power transformer 1, GV 2 lines of the main power source, CB 3 lines of the main power source, short circuit point 4, circuit breaker 5 of the ATS network point, CB 6 lines of the backup power source, GV 7 lines of the backup source power supply, busbar circuit breaker of substation 8, power transformer 9, current sensor of short circuit (ДТКЗ) 10, element MEMORY 11, element DELAY 12, element SINGLE-SELECTOR 13, element I 14, element NOT 15, element MEMORY 16, element DELAY 17, element SINGLE-SELECTOR 18, element AND 19, element MEMORY 20, element Z HOLD 21, element SINGLE VIBRATOR 22, element AND 23, DTKZ 24, element MEMORY 25, element DELAY 26, element SINGLE VIBRATOR 27, element AND 28, element NOT 29, element MEMORY 30, element DELAY 31, element SINGLE VIBRATOR 32, element SINGLE VIBOR 32, element AND 33, recording device (RU) 34.

The signal diagrams at the outputs of the elements shown in figure 1 with a short circuit at point 4 (see figure 1) have the form (see figure 2): 35 - output element 10, 36 - output element 11, 37 - output element 12 , 38 — output of element 13, 39 — output of element 14, 40 — output of element 15, 41 — output of element 16, 42 — output of element 17, 43 — output of element 18, 44 — output of element 19, 45 — output of element 20, 46 - the output of element 21, 47 - the output of element 22, 48 - the output of element 23, 49 - the output of element 24, 50 - the output of element 25, 51 - the output of element 26, 52 - the output of element 27, 53 - the output of element 28, 54 - the output element 29, 55 - output e ementa 30, 56 - the outlet member 31, 57 - the outlet member 32, 58 - the outlet member 33, 59 - 34 in RU.

In addition to the output signals of the elements of the control circuit, FIG. 2 also shows: t ₁ - the instant of occurrence of a stable short-circuit, t ₂ - the instant of disconnection CB 3, t ₃ - the instant of disconnection GV 2, t ₄ - the instant of shutdown 5 of the network item ABP, t ₅ - time of the trip with the acceleration of the switch 5 of the network item ABP, t ₆ - time of the trip CB 6.

The method is as follows.

In normal network operation, switches 2, 3, 6, and 7 are turned on, and switch 5 and 8 are turned off. There are no signals at the outputs of DTKZ 10 and 24, so the circuit is in control mode.

With a stable short circuit at point 4, a signal appears at the output of the DTKZ 10 (Fig. 2, Fig. 35, time t ₁ ). This signal goes to the input of the element NOT 15 and the signal disappears from its output (Fig. 2, Diagram 40), and the signal goes to the inputs of the MEMORY 11 and 16. The signals will be remembered by them (Fig. 2, Diagram 36 and 41) and will go to the inputs of the DELAY element 12 and 17. At the output of the DELAY element 12, the signal will appear after the delay time of the CB 3 protection actuation (Fig. 2, Diagram 37), and at the output of the DELAY 17 element, the signal will appear after the delay time of the protection of the GV 2 protection ( figure 2, diag. 42). The output signal from the DELAY 12 element will go to the input of the SINGLE-DISPLAY element 13, it will make one oscillation (Fig. 2, Diagram 38) and its signal will “discard” the memory from element 11, and will go to the first input of AND element 14. At this point in time (t ₂ , see figure 2), the switch 3 should open, however, due to any malfunction, it will not turn off and will not turn off the short-circuit current. Therefore, at the second input of the element And 14 with DTKZ 10 there will also be a signal (Fig. 2, Fig. 35). This will ensure the appearance of a signal from element And 14 (Fig. 2, Fig. 39), which will be received in RU 34 and there will appear information about the failure of disconnecting CB 3 (Fig. 2, Fig. 59).

After the delay time of the operation of the protection of the HS 2 from the output of the DELAY element 17, a signal will appear (Fig. 2, Diagram 46) which will go to the input of the SINGLE-VIBRATOR 18. It will produce one oscillation (Fig. 2, Diagram 43) and will “reset” its signals »Memory from element 16 (Fig. 2, Diagram 41) and will go to the second input of element And 19. At this point in time (t ₃ , see Fig. 2), the GV 2 will turn off and the short-circuit current will disappear. This will lead to the appearance of the output signal from the element NOT 15 (Fig. 2, Diagram 40), which, upon entering the first input of the And 19 element, will ensure the appearance of its output signal (Fig. 2, Diagram 44). This signal will go to RU 34 and there will appear information that GW 2 has turned off, and it will also go to the input of the MEMORY 20 element, where it will be remembered by it (Fig. 2, Diagram 45) and will go to the input of the DELAY 21 element. From the output of this element, the signal will appear after the shutter speed of the on-off switch 5 of the ABP network item (Fig. 2, Diagram 46) and will go to the input of the SINGLE-VIBRATOR element 22. It will oscillate one time and “reset” the memory from the element 20 (Fig. 2, diagram .45) and will go to the first input of AND 23.

The disappearance of voltage at the ABP network point from the main power supply, due to the shutdown of the hot water supply 2, will activate the automation of this item and, after the shutdown time of the on-off switch 5 of the ABP network point, it will turn on and turn on at short circuit. At the same time, at the input of DTKZ 24, a signal will appear (Fig. 2, Diagram 49) which will go to the second input of And 23 element and ensure its operation (Fig. 2, Diagram 48). The signal of this element will go to RU 34 and there will appear information on the inclusion of switch 5 on the short circuit (Fig. 2, Diagram 59), this signal will also go to the inputs of the MEMORY 25 and 30 elements, it will be remembered by them (Fig. 2, Diagram 50 and 55) and will go to the inputs of the DELAY element 26 and 31. From the output of the DELAY element 26, the signal will appear after the protection delay time with acceleration of the switch 5, (Fig. 2, Diagram 51) and from the output of the DELAY element 31, the signal will appear after the response delay time protection CB 6 (Fig.2, Fig. 56).

Leaving the DELAY 26 element, the signal will go to the input of the SINGLE-SELECTOR 27 element. It will make one oscillation (Fig. 2, Diagram 52) and with its signal “discard” the memory from Element 25 (Fig. 2, Diagram 50) and go to the first input element And 28. At this point in time (t5, see figure 2), the switch 5 should be turned off, but this will not happen due to any malfunction that occurred when it is turned on to a stable short circuit, so at the second input of the element And 28 will also be a signal from DTKZ 24 (Fig. 2, Diagram 49). This will lead to the appearance of an output signal with AND 28 (FIG. 2, FIG. 53), which will be received in RU 34 and there will appear information about the failure to turn off the switch 5 of the ABP network item (FIG. 2, FIG. 59).

The output signal of the DELAY 31 element will go to the input of the SINGLE-VIBRATOR 32. It will produce one oscillation (Fig. 2, Diagram 57) and with its signal “discard” the memory from the element 30 (Fig. 2, Diagram 55) and will go to the second input of the And element 33. At this point in time (4, see figure 2), CB 6 will turn off under the action of its protection, therefore, at the output of element HE 29, a signal will again appear (figure 2, diag. 54), which will be received at the first input of element And 33 It will work (Fig. 2, Diagram 58) and its output signal will go to RU 34, where information will appear on the disconnection of CB 6 (Fig. 2, Diagram 59).

Thus, the proposed method allows to obtain information about the failure of disconnecting the sectioning and disconnecting the main circuit breakers of the main power supply line, turning on and refusing to turn off the circuit breaker of the ATS network point and disconnecting the sectioning circuit breaker of the backup power supply line in the ring network.

Claims (1)

A method for monitoring the failure to turn off the sectioning and the deviation of the main circuit breaker of the main power supply line, turn on and turn off the circuit breaker of the main automatic transfer switch (ATS) circuit breaker, and turn off the sectioning switch (CB) of the backup power supply line in a ring network powered by buses of a two-transformer substation, which consists in fixing the inrush currents of short circuit (short circuit) and in measuring the time between them, characterized in that from the moment of the appearance of the first inrush short circuit current on the tires x the main power source at the same time begin the countdown of the response time of the protection of the sectioning and head switches of the main power supply line, at the same time control the short-circuit current disconnection time and, if at the end of the shutdown protection shutdown time the short-circuit current did not turn off, but disconnected at the end of the shutdown time operation of the protection of the main switch, then make a conclusion about the failure of disconnecting the sectioning and disconnecting the head switches of the main power supply line, from the moment of switching off of the first short-circuit current surge begins the countdown of the shutter-off time of the circuit breaker of the ABP network item and at the end of the countdown of this time on the tires of the transformer of the backup power supply, the appearance of the second short-circuit current surge is controlled, and if it appears, they conclude that this switch is turned on to the short-circuit, from the moment of the appearance of the second inrush short-circuit current, at the same time, the delay time of the protection operation starts with the acceleration of the circuit breaker of the ABP network point and the protection delay time of the protection of the CB backup line power supply and, if at the end of the shutdown time of the protection operation with the acceleration of the circuit breaker of the ABP network item, the second short-circuit current surge did not turn off, but turned off at the end of the shutdown time of the protection of the CB line of the backup power supply, then a conclusion is made about the failure to open the circuit breaker of the ABP network item and disconnecting the CB line of the backup power source.

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