SU1001272A1 - Device for three-phase automatic reconnection of power transmission line - Google Patents

Description

The invention relates to electrical engineering, in particular, to relay protection and automation of power systems.

Devices for automatic reclosing (AR) are widely used in power systems t.1

However, most of them produce automatic reclosing even with short circuits (short-circuit) close to the end of the line switched on first, which in some cases is very undesirable, since after an unsuccessful automatic reclosing the transmission line with such damage can the dynamic stability of adjacent links is disturbed, the switch is damaged, etc.

A device for automatic reclosing is known, which partially eliminates this drawback. It contains at each end of the line re-inrunner blocks without line voltage control (ARA-BK), with control of the voltage barriers (ARA-NY, and with control of synchronism between the line voltages in the busbars (ARA-COP), and also a voltage busbar relay relay. When remote from both ends of the short-circuit line and high-frequency protection of the line is triggered, two-way automatic reclosing is performed (so-called BAPV).

k.z. at one end of the line is triggered. It filters the direct voltage relay relay and prohibits the operation of the AR / CU unit of this end. At the opposite end of the APV-BK, the automatic reclosing switch is activated and produces, and when it is successfully turned on, the first end is turned on from the APV-NN or APVKSS23 blocks.

However, such a device has a limited scope, since it can only be used where a two-way line can be switched on without synchronization checking.

It is also known a device for the automatic reclosing of an electric power line, using which an automatic reclosing of the automatic reclosing is provided at one end and another at the other end is automatic reclosing, automatic reclosing, or automatic reclosing. lines where simultaneous activation of switches at the ends is unacceptable. In this case, if at the first end the ARF-AC is prohibited (or ARA-OH), then at the other end of the line the permission to perform ARA is first transmitted via the communication channel.

The corresponding units of the device, necessary for the implementation of the ARF-BC, and the ARA-COP, are described, for example, and the -APS-HH block is the letter,}.

The closest to the technical entity to the proposed offer is a device for three-phase automatic repeated switching on of the electric transmission line, equipped with frequency protection and a communication channel.

between the ends of a ... linear line equipped with measuring current transformers and voltages at each end and a switch. with a control key containing a start-up unit whose inputs are assigned to be connected to the switch contact block and to the output of the control key, the output of the start-up block is connected with the first inputs of the block re. and. Element I, and 15 also with the holding input of a relay body with self-holding, the main inputs of which are intended to be connected to the variable current transformers, and voltage. - Output 20 of the relay organ, with self-holding is connected with the transmission input of the communication channel, and through the element NOT and the two-position switch in the first position connected to the second input of the element 25 and I, the receiving input of the communication channel

the second position of the element and the second inlet of the element. And the third input of which is connected to the output of the DELAY element, p TO RETURN, the input of which is intended to be connected to the output of the high-frequency protection. The output of the element I is connected to the second input of the repeated on, the output of which is intended to be connected to the switching circuit of the switch. The reclosing unit includes well-known elements, including the block. control the presence of voltage on the line. The relay element and the element are NOT intended to prevent the automatic reclosure of the circuit breaker (without; voltage control) with close (heavy) short circuit when the relay element is activated. .

The signal at the output of this organ is also self-arising, if the signal appears at the output of the start-up unit, which corresponds to the emergency shutdown of the switch. The output signal of the relay organ with co-CQ power hold is supplied to the transmitting input of the communication channel, and also causes the signal to be removed from the second input of element I. Failure of this element as a result of And provides f. the absence of a signal at the second input of the reclosing unit and, therefore, the prohibition of the automatic reclosing device-AC at this end of the line.

At the opposite end of the line, a signal appears at the receiving end of the communication link. This signal through a two-position switch (in position II) is fed to the second input of the element And and / if at this end also acts as a block 65

start-up and high-precision protection, through the element I is allowed to produce APV-BK. If the switch is successfully turned on, one of the ends of the line (opposite) is made by APV-NN or APV-KS 5.

The disadvantage of the known device is the need to use a special communication channel between the ends of the line, which requires additional costs for the construction of such a channel, and also reduces the reliability of the device.

The purpose of the invention is to reduce the cost and increase the reliability of the automatic reclosing device.

. This goal is achieved by the fact that, in a device for three-phase automatic re-activation of a power line equipped with high-frequency protection and equipped at each end with measuring current and voltage transformers and a switch with a control switch containing a voltage presence monitoring unit, the line input which is intended for connection to a voltage transformer, a two-position switch., a start-up unit, whose inputs are intended to be connected to the auxiliary contacts of the switch and to the output control key, block repeat. .on switching on, the output of which is intended to be connected to the switching circuit of the switch, a self-retaining relay body, the first and second inputs of which are started to connect to current and voltage measuring transformers, the RETURN DELAY element, the input which is / is intended to be connected to the output of the high-frequency protection, the elements AND and NOT, while the output of the start-up block is connected to the first input of the re-starting block, the first input of the AND element and the holding input of the relay element, the output of which is through the H element E is connected to the second input of the element. And, the third input of which is connected to the output of the DELAY TO RETURN element, the output of the element AND is connected to the second input of the reclosing unit, the second element NOT and the DELAYED DELAY element are additionally entered, and the fourth input is provided , at the same time between the input and output of the DELAY TO CLIPPING element, a two-position switch is switched on, the output of the AND element is connected to the input of the DELAYER TO WORKING, the output of which is connected to the second input of the recloser neither, but the fourth input of the element And through the second element is NOT connected to the output of the control unit ngshichi voltage on the line.

The drawing shows a block diagram of the proposed device.

The device contains a power line 1; high voltage protection 2 lines; current and voltage measuring transformers, respectively, 3 and 4 J Switch 5 J switch control key b, the signal to you -. the course appears at the time of the command to turn on and does not disappear until the switch-off command is given the key; The start block 7, at the first input of the block, is given a signal from the auxiliary contacts of the switch, which is turned off), and the other from the control key; the output signal of the start block exists when there are signals 15 on two of its inputs, i.e in case of inconsistency between the position of the switch and its control key. .

The reclosing unit 8 contains sub-blocks of APV-BK, APV-NN, APV-KS 20 in it is formed - output signal including when implementing all of the listed types of APV; when the signal at the second input of the start block 8 is triggered, the APV-BK subunit 25 starts up when a signal appears at the first input of the block 8. The APV-NN or APV KS subblock is started. After the operation of the corresponding subblock, a signal appears at the output of the block.

The device also contains a logical element And 9, having four inputs relay body 10 with self-holding which serves to assess the gravity of the KZ, the proximity of the location of the short circuit from the end of the ac line. It can be made responsive to the magnitude of the current, voltage, resistance, or line power, and should be triggered when the aforementioned values reach a given level. Signals from devices that determine the distance to the short circuit can also be used. The settings of the operation of the relay organs of the two ends of the line must be chosen in such a way that the zones of their action (1 along the length of the line) do not overlap, i.e. to prevent simultaneous operation. relay bodies of the two ends of the lee-. SRI. The organ has a time delay for the return, a longer switch-off time of the switch 5. The signal at the output of the organ appears only if there is a signal at its holding input coming from the output of the start block 7. The output signal of a 55-hold relay organ exists for as long as there is a signal at the hold input. :

The structure / structure includes first and second logical elements. NOT 11 and 12, respectively; The unit 13 controls the presence of voltage on the line, which can be performed using phase voltage (linear) and zero sequence voltage, or using voltage linear (phase), reverse and zero sequence (1.5). A signal at the output of a block appears when voltage is present, unbalanced and unbalanced.

The time delay of the DELAY 14 DELAY 14 element is selected with the necessary margin of a greater amount of on-time switch (opposite end of the line) and the response of the control unit for the presence of voltage on the line. .

The device contains a two-position switch 15, at the end of the line the switch of which should be turned on first, if the relay bodies do not operate at both ends of the line, the switch is set to position I, and at the other end of the line to position IT; the DELAY TO RETURN element 16, its time delay is selected with the necessary margin of a greater amount of time delayed by the APV-B and the additional delay determined by the element DELAY TO OPERATION 14.

Line 1 transmission is equipped with high-frequency protection 2 and is equipped with. each end of the measuring current transformers 3 and voltage

4 and switch 5 with key 6 controls. The switch contacts are connected to the inputs of the start block 7

5 and the output of the control key 6. The output of the start-up unit 7 is connected to the peep inputs of the reclosing unit 8 and element 9, as well as to the holding input of the relay body 10 with self-holding, the inputs of which are connected to the measuring current transformers 3 and voltage 4. The output of the relay body 10 with self-holding across the element HE : 11 is connected to the second input of the element. And 9, the third input of which is connected via the element DELAY TO RETURN 16 to the output of the high-frequency protection 2. The fourth input of the element AND through the element NOT 12 is connected to the output of the voltage control unit 13 line, the input of which is connected to the voltage transformer 4 The output of the element And 9 through the DELAY 14 OPERATION element 14, between the input and output of which the two-position switch 15 is connected, is connected to the second input of the reclosing unit 8, the output of which is connected to the switching circuit of the switch 5 .

The device is in the standby state when the switch 5 on line 1 is turned on. The sequence of re-activation at the ends of the line when a relay body 10 with self-holding is triggered is automatically selected: the switch on the end of the end-on-relay body did not operate first, i.e. remote from the place k.z. the end. The turn-on sequence at a distance from both ends of the AD line, when no relay body 10 is triggered, is defined by the position of switch 15. For e-tom we conditionally call the end of A the end of the line / where the switch 1 5 is in position closed j

end B is the end of the line where switch 15 is in-position (G (open. At end A) output signal element AND 9 is fed to the second input of reclosing unit 8 without delay, and at end B with time delay determined by element DELAY 14. Release. (Ci time of the automatic reclosing in the sub-block of the recloser-BK at both ends of the line are assumed to be the same.

In the event of a short-circuit remote from end A, the relay body 10 by self-holding at this end does not work. After the high-frequency protection 2 is triggered and the switch 5 is turned off, the start-up unit 7 is activated and sends a signal to the first inputs of the AND 9 element and the re-activation unit 8, as well as to the holding input of the relay organ.10 with self-holding. Due to the failure of the relay body 10, the signal at its output does not appear and the output signal of the NB 11 element continues to flow to the second input of the And 9 element. The third input of the element And 9 receives a signal from the output of the element DELAY TO RETURN 16 / since the high-frequency protection 2 is triggered. At the fourth input of the element, there is also an E signal, because, due to the absence of a line, the voltage control unit 13 does not work, line and signal at the output element, NOT 12 is present. Thus, on all four inputs of the element AND 9, signals are present and it is triggered. Its output signal through the dip switch 15 is fed to the second input of the reclosing unit 8, thus ensuring the possibility of detecting at the A end APV-VC (without additional delay).

At the end of B at the considered c. The relay body 10 with self-holding can trigger and when the start-up unit 7 starts, a signal appears at the output of the relay body 10. As a result, the HE IT element is triggered, its signal disappears, which prohibits the triggering of the element 9. Koitsi In APV-BK. If the switch is successfully turned on at the end A in the considered case, the B end may be made by APV-NN or APV-KS. There will be no unsuccessful switching on from the first end of the connection at the B end.

In the event of a short-circuit near the end A, the relay body 10 with self-holding at this end is triggered. Therefore, after the switch 5 is turned off and the start-up block 7 is triggered, a signal appears at the output of the relay element 10, which will exist until the output signal of the start-up block 7 disappears. As a result, the signal disappears from the output of the element NOT 11, a,., Consequently, and from the second input of the element I 9, which leads to the prohibition of the ARF-VC, i.e. to disable the switch from the automatic reclosing switch of this end first. -. At the end B with the considered short-circuit. relay organization. 10 self-holding does not work and provides. The ability to perform ARA-B with an additional slowdown, determined by the element DELAY TO OPERATION 14.

Switching on the switch at the end A in this case is possible from the APV-NN or APV-KS only, if the switch is successfully turned on at the end of B.

In the event of a short-circuit remote from the end A and from the end B, when the relay body 10 with self-holding does not work at either end, it is possible to carry out an ARC-BK at both ends. The first start is made at the end A without additional deceleration (switch 15 is in position I). At. switching on the switch at the end A successfully, a voltage appears on the line and a voltage control unit 13 on the line - at the B terminal is triggered, resulting in a signal from the output of the HE element 12, and consequently, from the fourth input of the AND 9 element, which leads to the prohibition of the APV-BK at the end of B. Turning on the switch 5 on this, the end can only occur from APVNN or APV-KG.

If the switch at end A fails to turn on unsuccessfully, in this case, the high-frequency protection of the line is re-triggered, as a result of which the switch at end A is turned off and with the help of other devices a special prohibitory signal of all types of ARC is transmitted to end B.

Claims (5)

Thus, by introducing a small additional delay, exceeding with the necessary reserve the sum of the switch on and response times of the line voltage monitoring unit, without first communication channel between the ends of the line, the first activation (from AR) from the remote location: k; h . end of line. It should be borne in mind that this additional deceleration will manifest itself only when it is first switched on from the end of the line where this deceleration is out of I switch 15 - to position II). Compared to the prototype device, the proposed has much greater reliability, since it does not use a communication channel between the end of the line, and the reliability of the additionally introduced logic elements is much higher than the reliability of the communication channel. For the same reason (not using the link), the proposed device is cheaper. The technical and economic efficiency of the proposed device is mainly determined by the savings in the costs of building and operating the communication channel. The implementation of the invention cannot be difficult as the proposed device assistance of simple and well-known logic elements, which are widely used nowadays. Formula of the Invention A device for three-phase automatic reclosing of a power line, equipped with high-frequency protection and equipped at each end with current and voltage measuring transformers and a switch with a control key, containing a control unit for the presence of voltage on the line, the input of which is intended to be connected to the voltage transformer, a two-position switch, a start-up unit whose inputs are designed to connections to the circuit breaker contacts and to the output of the control key, a reclosing unit, the output of which is intended to be connected to the circuit breaker switch, p Lead body with self-holding, the first {and second inputs of which are intended for connection to current and voltage measuring transformers, the element RETURN DELAY, the input of which is intended for connection to the output of high-frequency protection, elements AND and NOT, while the output of the start-up unit connected to the first input of the reclosing unit, the first input of the element I and to the input holding the relay organ, the output of which through the element is NOT connected to the second input of the element AND, the third input of which is connected to the output of the element DEADER SC ON RETURN, and the EXIT of the element AND is connected with the second input of the reclosing unit, which is due to the fact that, in order to reduce the cost and increase reliability, the second element is NOT and the DELAY TO CRITCH element are also added to it, and the AND element is equipped with the fourth an two-position switch is switched on between the input and output of the DELAY FOR SERVICE element, the output of the element AND is connected to the input of the DELAY FOR TRANSITION element, the output of which is connected to the second input of the reclosing unit,. and the fourth input of the AND element. Through the second element is NOT connected to the output of the voltage monitoring unit on the line. Sources of information taken into account during the exertiz 1. Bogorad A.M., Nazarov Yu.G. Automatic reclosing in power systems. M., Energie, 1969, p. 336. 2. USSR author's certificate for application No. 2739707/07, cl. And 02 H 3/06, 1979. 3. USSR author's certificate for application No. 2844011 / 24-07, cl. H 02 H 3/06, 1979. 4. Kolonsky I.E. About additional possibilities of three-phase auto-reclosing on lines of intersystem weak communication. : Electricity .1977, №8, p.74-75.f 5. Strelkov V.M., Fokin G, G., Yakubson G.G. Voltage monitoring in TAPV circuits of power lines with voltage of J30 kV and above. Electric power stations, 1978, 9, p. 58-65. about , -eleven nl yf .III