SU1368942A1 - Method of locating damaged portion of power line with two-way supply by directed pulse - Google Patents

Abstract

The invention relates to emergency control automation of electrical power transmissions mainly for agricultural purposes. The purpose of the invention is to increase reliability. The goal is achieved by the fact that when a fault occurs on a line, a short circuit current is generated. flows to the place of damage both from the side of the main switch (GW) line, and (after activation of the ATS) from the point of the ATS (PAVR). After disconnecting the HS and the PAVR switch, all SKA are turned off, in their control units (CU), the transmitters of the high-frequency switching pulse are started, which are transmitted by wires of the line in the direction opposite to the direction of the short-circuit current. The reception of these pulses in the SKU control unit ensures the inclusion of all the SKA, except those closest to the location of the short-circuit. The voltage in the intact areas is restored by automatic re-activation of the HW and the PAVR switch. 1 il. with

Description

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The invention relates to the power industry, namely to the emergency control automation of power transmission lines for mainly agricultural purposes.

The purpose of the invention is to increase the reliability after an unsuccessful reclosure of the main switch.

The drawing shows a two-way power line-transmission scheme and a block diagram of a control unit of a sectioning switching device that implements a method for isolating a damaged section.

Head switches 1 and 2 of inter-reserved power lines have a relay protection unit 3 and automatic restarting (AIIB) 4. The lines are repeatedly partitioned by sectioning switching devices (SKA) 5, equipped with control units 6 (CU).

The CU 6 SKA contains voltage sensors 7 and 8, current sensor 9, power direction relay 10, current relay 11, voltage relay 12, two HE elements 13 and 14, six I elements 15-20, switching organ 21, transmitter 22 and the signal receiver 23, the delay element 24, the memory elements 25 and 26 (triggers), the Shutdown electromagnets 27 and the switch-on 28 of the SKA, the block-contacts 29 of the SKA. Bin-lirers are connected via a normally disconnected DVR switch 30.

The control unit in the method of isolating the damaged area works as follows.

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this output element And the 17th signal is not.

After the shutdown to. h Since the main subtractor 1 from protection 3, there is a best pause, no signals are received to elements I 1 and 12, therefore, at the outputs of the HE elements 13 and 14, and then the AND 16 element appears the logical 1 signal, which is fixed by the trigger rum 25 and, at its output, logical 1, containing information that a short circuit current has passed. and there is a lack of tension.

15

20

Unit 4 of the APB on the head switch 1 with a certain shutter speed makes a test switch of this switch. Since this inclusion leads to the flow of short-circuit current, the output of Element I 17 appears logical 1, because the second input of this element has a signal from the output of the trigger 25. The signal from the output of the element 17 is detected by the trigger 26. This signal carries information about the fact that a short-circuit takes place on the line behind the installation site of this SKA, and the voltage is lost and the short-circuit current passes again.

thirty

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When a second timeout occurs at the output of the element And 16, a signal of logical 1 appears, which arrives at the input of the element 20. At the other input of this element, the delay time specified by element 24 also receives a signal that causes the output from the element And 20 signals per electro

In normal mode, the output of the 40 and 27 is to disable the partitioning

this output element And 17 no signal.

After the shutdown to. h the head switch 1 from protection 3 causes a dead time pause, no signals are received to elements I 1 and 12, therefore, at the outputs of elements NOT 13 and 14, and then element I 16, a logic 1 signal appears, which is detected by the trigger 25 and the output of logic 1, containing information that passed the short-circuit current. and there is a lack of tension.

Unit 4 of the APB on the head switch 1 with a certain shutter speed makes a test switch of this switch. Since this inclusion leads to the flow of short-circuit current, a logical 1 signal appears at the output of Element And 17, because at the second input of this element there is a signal from the output of the trigger 25. The signal from the output of the element 17 is detected by the trigger 26. This signal carries the information that the short circuit takes place on the line behind the installation site of this SKA, the voltage disappears and the short circuit current flows again.

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When a second dead pause occurs at the output of the AND element 16, a logical 1 signal appears, which arrives at the input of the AND 20 element. At another input of this element, after a time delay specified by element 24, a signal also arrives, which causes the output from the AND 20 output. signal to the electromagnet

1 1 (overcurrent relay) signal corresponds to a logical O, and the output of element 12 (voltage relay) is logical 1. These signals are inverted by elements 13 and 14, and, respectively, 1 and O are allocated at the inputs of elements 15 and 16, respectively. The output signal of the element 15 (logical 1) memory elements 25 and 26 are set to their original position (at the output O).

When a stable short-circuit occurs on the line. At the input of element 11, a signal appears corresponding to logical 1, which is fed to the input of element And 17. However, at the second input of this element is a logical O signal (trigger 25 is in the initial state) of the switching device. When the SKA is automatically disconnected, its block contacts -29 are closed, which ensures the start of the transmitter. Since the g power relay does not work (the direction of the short-circuit current coincides with the direction of the normal power supply), then on the output of the element 18 there is no signal and the switching body does not work, therefore, the transmitter sends an impulse to the preceding SKA, and the receiver accepts this impulse from the subsequent SKA. If the receiver accepts an inclusive impulse, then at the output of the AND 19 element appears: sig0

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the current that is supplied to the electromagnet 28 is turned on and the SKA is turned on. Since the BU is closest to the place k.z. Since the SKA does not receive a trigger pulse, this SKA remains disabled. Voltage on the part of the line to the point of cs. recovered by the second cycle of the automatic reclosing of the main switch.

After turning on the normally disconnected switch 30 from the AVR and its disconnection from the SKA protection, located behind point k, h., Are turned off in the same way as described. In this case, since the direction of the current k.z. does not coincide with the direction of the normal power supply; a signal appears at the output of the And 18 element. The switching authority performs switching of the transmitter and receiver connection, which ensures the direction of the trigger pulse from the previous SKA to the next one. Since the receiver in the control unit is closest to the location The SKA does not receive a signal, this SKA remains disabled. The remaining SKA on the considered part of the line is turned on, after which the part of the line is energized by switching on the automatic reclosing circuit breaker. Thus, the damage is highlighted.

Claims (1)

Invention Formula A method of isolating a damaged section of a power line with two-sided power supply using a directional pulse, based on equipping the line with a double-reclosing head switch, normally disconnected by an AVR switch (equipped with automatic reclosing), capable of switching the short-circuit current and sectioning 1 switching devices in control units which include transmitters and receivers of a high-frequency pulse, which consists in the following: if a permanent damage occurs on the line after the resulting outage and does not hasty reclosure brain switch combination of features of current passage sc and the disappearance of voltage for a predetermined time in the control units of the sectioning switching devices located between the main switch and the KS place, form commands to disconnect the sectioning devices, using block contacts 68942 the disconnected sectioning apparatus, which is closest to the location of the short-circuit, starts a transmitter in its control unit, with which a high-frequency pulse is sent to the line in the direction opposite to the direction of the short-circuit current, and after separation of the short-circuit. from the main power source with 10 automatic reclosing switches on the main switch, and on part of the line behind the short circuit, the automatic breaker switch is turned on, which is disconnected from protection, which ensures (by the same way, separation of the short circuit space from the backup power supply is performed, then the automatic reset switch is turned on AVR, characterized in that, in order to increase reliability 20 after an unsuccessful automatic reclosing of the main switch, all sectioning devices located between the main switch are automatically switched off (by a combination of the two signs indicated) with the help of the block contacts of which, in the control units of these devices, trigger transmitters which produce an inclusive pulse directed from each subsequent (in the course of normal power supply) to the previous control unit of the sectioning apparatus, where this pulse is received and its action includes data-driven blocking units, at the same time, only the one closest to the location of a short-circuit remains disconnected. the device, into the control unit of which the switch-on pulse did not arrive, but on parts line after place k.z. after disabling the switch protection, the ABP, as described above, automatically disconnects all sectioning devices, in control units with which the fact that the current direction does not coincide. with the direction of the normal power switch the connection of the transmitters and receivers of the switching pulse on the contrary, which ensures its transmission from each previous (along the normal power) to the subsequent control unit of the sectioning device, where this pulse is taken to its action include impulse-controlled sectioning devices.