SU1115163A1 - High-voltage switch-gear - Google Patents

Abstract

HIGH VOLTAGE DISTRIBUTION DEVICE, containing high voltage switches and disconnectors connected in a hexagon ring pattern, to the vertices of which are connected transformers with low voltage side switches and a power line alternately, characterized in that, in order to improve the reliability of the power supply to consumers , three separators are inserted in it, connected between transformers and lines opposite to those in the hexagon scheme, and a block is introduced automatics consisting of three channels, each of which contains the first and second elements AND with a memory with six inputs and two outputs, the third and fourth elements AND with two inputs and three outputs, the fifth element AND with two inputs and two outputs, the control unit of the low voltage side switch of the power transformer, which has on and off inputs, and the fixing unit of its open position, the control unit of the separator connected to the power transformer, and the fixing unit of its on position, the unit Switching the output transformer protection relays to the output relays of the line to which the transformer is connected by a separator, as well as three fixation blocks for the three channels of the automation unit, three fixation blocks for the protection of the first, second and third power lines, six fixation blocks for the off position of six O) switches each element of the three channels of the automation unit, the first inputs of the first and second elements I are connected respectively to the outputs of the fixation blocks Protecting lines adjacent to the transformer, their second and third inputs connected with aootvetstvenno vyR1 moves disconnected position fixation circuit blocks adjacent to line 00 Od, their fourth inputs coupled to the output of the OFF lock position switches, i adjacent to the transformer by sosedi. The lines and their fifth inputs are connected to the output of the time element, their first outputs are connected to the disconnecting inputs of the control unit by the low voltage side switches of the transformer, the second outputs are connected to the first inputs of the third and fourth elements, respectively, the second inputs of which are connected to the output block fixation off position you

Description

the low voltage side switch of the same transformer, the first outputs of the third and fourth elements And are connected to the input of the separator control unit, their second outputs are connected to the first input of the fifth And element, the second input of which is connected to the output of the separator on position of the separator, and the third outputs the third and fourth elements And are connected to the input of the switching unit

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output transformer protection relays to the output protection relay of the oppositely located line, the first output of the fifth element I is connected to the switching control switch input of the low voltage side of the transformer, its second output to the memory inputs of the first and second elements I, the time element input connected with outputs of fixing units for the operation of power line protection.

This invention relates to electrical engineering, in particular, to high-voltage open and closed type electrical switchgears. Ring circuits of high voltage switchgear, such as a quadrilateral, are known, where an increase in the reliability of power supply is achieved due to additional capital investments in the installation of a replacement switch and load switches, which limits the scope of application; switchgear (RU) circuits with switch voltage switches. 330 kV and above O. High voltage switchgears are known; they are made according to ring circuits in the form of a hexagon 2. However, they are used extremely rarely because they are not sufficiently reliable in the repair mode when, during a short circuit at the connection that coincides with the repair of one from circuit breakers, one of the connections is additionally de-energized or two connections are separated from the switchgear. The purpose of the invention is to increase the reliability of power supply to consumers, in particular, to keep all transformers in operation when a damaged power line is disconnected, which coincides with the repair of one of six switchgear circuit breakers. This goal is achieved by including a high voltage switchgear containing switches and high-voltage disconnectors, connected in a hexagon-shaped ring circuit, to the vertices of which are connected transformers with switches on the side Voltage and power lines alternately, three separators were inserted, connected between transformers and hexagonal lines opposite to the circuit, and also an automation unit was inserted consisting of a track channel, each of which contains the first and second memory elements with six inputs and two outputs, the third and fourth elements And with two inputs and three outputs, the fifth element And with two inputs and two outputs, the control unit of the low voltage side switch of the power transformer, having switching on and off inputs, and blocking its disconnected position, the control unit separating the relay connected to the power transformer, and the clamping module of its on position, the switching unit of the output transformer protection relays to the output relay of the line to which the transformer is connected with a separator, and common for the three channels of the automation unit three fixation blocks of the action of relay protection of the first, second and third power lines, six fixation blocks of the open position of six switches high voltage and time element, with each of the three channels of the automation unit having the first inputs of the first and second elements I connected respectively to the outputs of the protection protection fixing unit 31 lines adjacent to the transformer, their second and third inputs are connected respectively to the outputs of the disabled position fixing block switches adjacent to the line, their fourth inputs are connected to the output of the latching blocks of the disconnected position of the switches adjacent to the transformer on the side of the adjacent line and their fifth inputs are connected to the output of the This time, their first outputs are connected to the disconnecting inputs of the low voltage side switch control unit of the transformer, the second outputs are connected to the first inputs of the third and fourth And elements, respectively, the second inputs of which are connected to the output of the low voltage side switch transformer, the first outputs of the third and fourth elements I are connected to the input of the separator control unit, their second outputs are connected to the first input of the fifth element I, the second input is cat connected to the input of the switching unit of the output protection relay of the transformer to the output of the protection relay opposite to the line, the first output of the fifth element I is connected to the on input of the control unit of the side switch low voltage transformer, the second output - with memory inputs per. The second and second elements And, the input of the element of time is connected to the outputs of the fixing units of the operation of the protection of electric transmission lines. FIG. 1 shows the layout of the proposed switchgear; in fig. 2 shows the configuration of the circuit after disconnecting the damaged power lines during the repair of the circuit breaker (six variants of the circuit are shown (a, b, c, d, d, e) according to the number of switches RU). The device contains power lines (PTLs) 1-3 and transformers 4-6 connected in a hexagon circuit with switches 7-12 (circuit disconnectors are not shown). The separators 13–15 are connected between transformers 4–6 and opposite to those in the transmission lines 3, 1, and 2. On the lower voltage side 34, transformers 4–6 are connected to the load by switches 16–18. The automation unit contains blocks 19-21 for latching the operation of relay protection of transmission lines 1-3, blocks 22-27 for fixing the open position of switches 7-12, respectively, time element 28, elements 29-34 of the AND operation with the element of the network, each with 5 inputs and two outputs, as well as a special memory input, elements 35-43 of the logical AND operation, having two inputs and up to three outputs, control switch switches 16-46 16-18, having shut-off inputs 44-1, 45- 1, 46-1 and comprising inputs 44-2, 45-2, 46-2; units 47-49 of control of separators 13, 15 and 14, blocks 50, 51 and 52 of fixing the open position of switches 16-18, blocks 53, 54 and 55 of fixing the on position of separators 13-15, blanks 56-58 of switching the output protection relays. transformers 4-6 on the output protection relay lines 3j 1 and 2, respectively. The device works as follows. In case of stable short circuit (SC) 59 on power transmission lines 2 during repair of switch 7, after switching off switches 8 and 9, transformer 4 turns off from the switchgear circuit. Its connection to the switchgear circuit is performed by the separator (OD) 13. Since the OD does not switch load currents, it is necessary to disconnect the low voltage side switch 16 of the power transformer 4 first. This is done as follows. The inputs of the block 29 And with the memory element are supplied with signals from the block 20 of the LZ actuation latch 2, from the blocks 23, 24 and 22 of the latching of the open position of the switches 8, 9 and 7 and from the time element 28, the Block 29 is triggered, and from its first the output signal is sent to the shut-off input 44-1 of the switch control control unit 16. The shutdown of the switch 16 is detected by the operation of the block 50, after which the block 35 is triggered, and from its first output the signal is fed to the input of the control unit 47 of the OD 13. OD 13 w: , which is fixed by block 53. At both inputs of block 37, And served Nala output unit 53, from the second output unit 35. The unit 37 is activated and with its first output

the signal is applied to the on input 44-2 of the control switch 44. The latter is turned on and connects the load to the transformer 4.

The signal from the second output is fed to the memory input of the block 29, the circuits automatically return to the initial state (Fig. 2a). All transformers RU are in operation.

If now the disconnection of the supply line, for example line 1, occurs, then all the transformers RU are connected to one line 3.

If the transmission line 3 is disconnected, the automation will operate the second cycle, which will end up by connecting the transformer 5 to the transmission line 1 using OD 14.

The scheme of automation in this case works as follows. The operation of the power transmission line 3 is fixed by the block 21, the off position of the switches 10, 11 and 9 is fixed by the blocks 25, 26 and 24 with the time delay the block 28 is triggered. From the outputs of the listed blocks, the signals go to the inputs of the block 31 that is triggered. From its first output, the signal goes to the shut-off input 45-1 of the switch control unit 45, the shutdown of which is fixed by the block 51. From the second output of the block 31 and from the first output of the block 51, the signals arrive at the inputs of the block 38 that is triggered. From its first output, the signal is fed to the input of the control unit 48 of the OD 14. After switching on the OD 14, the block 40 is triggered, since both inputs are fed from the second output of the block 38 and from the output of the block 54 of the fixed position ON OD 14 From the first output of the block 40 the signal is applied to the switching input 45-2 of block 45, which causes the switch 17 to turn on, and from the second output of block 40, the signal is fed to the memory input from block 31. The automation circuit returns to its original position.

Power supply to consumers is provided by transformers 5 and 6, connected to power transmission lines 1.

With a stable fault 60 on the transmission line 1 during the repair of switch 8, after switching off the switches 7 and 12, transformer 4 is disconnected from the switchgear circuit. Its connection to the switchgear is possible with the aid of the OD 13 after the preliminary disconnection of the switch 16 of the transformer low side. After switching off the switches 7 and 12 at the inputs of the block 30, there are signals necessary for its operation: from the latch block 19, the operation of relay protection of power lines 1, from the blocks 22, 27 and 23 latching of the switched off position of the switches 7, 12 and 8, from the element 28. automatics.

Block 30 is triggered and from its first output a signal is supplied to the shut-off input 44-1 of the switch control control unit 16. After the switch 16 is turned off, the block 50 is turned on and the unit 36 is turned on, the first input of which is given a signal from the second output of the block 30, and the second input is from the second output of block 50. Block 36 is triggered, and from its first output a signal is sent to block 47 of control OD 13, the activation of which is recorded by triggering block 53. From the output of block 53, the signal goes to the first input of block 37 AND on the second entrance The signal is supplied from the second output of block 36. Block 37 is triggered, from the third output of block 36, a signal is fed to the input of the switching unit of the relay protection of the transformer 4 to the output circuits of protection of TL 3 From the first output of block 37, the signal is fed to the switching input 44-2 of block 44 control switch 16, which is turned on again. From the second output of block 37, a signal is applied to the memory input from block 30. The automation circuit returns to its original state. Transformer 4 is connected to the rest of the switchgear (Fig. 26).

When the next line is disconnected, for example, in a thunderstorm, the transmission line 3 is disconnected, the second cycle of automation operates, and the transformer 6 is separated by a separator 15 to the transmission line 2.

Considered the work of the first channel automation. The second channel of automation contains blocks 31, 32, 38-40, 45, 48, 51, 54 and 57 to work when the transformer 5 is de-energized in case x, when a stable short circuit on power lines 2 or 3 coincides with the repair of switches 10 or 11. At the same time The transformer 5 is connected to the switchgear circuit with a separator 14. The automation works in a similar way to the automation of the first channel.

The third channel of automatics contains blocks 33, 34, 41-43, 46, 49, 52, 55, 58 and works when the transformer 6 is de-energized in cases when the stable short circuit on the power transmission line 3 coincides with the repair of the switch 11 or 12. At the same time, the connection of the transformer 6 to the switchgear circuit is executed by the separator 15. The automation works in the same way as for the first channel.

FIG. 2 shows the state of the proposed improved hexagon scheme after the operation of the first cycle of automatics for the case of a coincidence of short-circuits on power lines with repair of a switch,

Six variants of the circuit are shown, according to the number of switches. It is also obvious the expediency of using the second cycle of automatic equipment in case of emergency disconnection of the second line, through which the switchgear is powered.

The proposed scheme ensures that all transformers remain in operation and that the failure of the switch with the repair of another switch coincides, which is a calculated case for determining the reliability level of the switchgear circuit. In cases where the switchgear circuit contains only two transformers, this design case excludes full switching off of switchgear, providing power to consumers for the case when the switchgear is an element of the substation, and power output when the switchgear is an element of the power station.

The latter case is the most favorable for the hydroelectric power station and the pumped storage power plant from the conditions for the rapid restoration of the synchronous operation of the power plant with the power grid.

The proposed scheme expands its range of application at higher voltage switchboards when a load switch is used instead of separators.

The use of load breakers also improves circuit performance by

drastically reducing the operating time of the circuit breaker (0.08 s instead of 0.5 s) and reducing the number of operations — disconnecting the switches on the medium and low voltage side and transferring the tripping signal to. feed end of the line.

In the case of the use of load breakers, the circuit allows not only transformers to be kept in operation, but also disconnected unaffected power lines.

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Claims (1)

HIGH VOLTAGE DISTRIBUTION DEVICE, comprising high voltage circuit breakers and disconnectors connected in a hexagonal ring circuit to the tops of which transformers are connected alternately with circuit breakers on the low voltage side and power line, characterized in that, in order to increase the reliability of power supply to consumers, three separators are introduced, connected between the transformers and the opposite lines in the hexagon circuit, and an automatic unit is introduced ki, consisting of three channels, each of which comprises first and second AND gates with memory with six inputs and two outputs, the third and fourth elements And with two inputs and three outputs, a fifth AND element with two inputs and two outputs, a control unit for a low-voltage side switch of a power transformer having switching on and off inputs, and a unit for fixing its disconnected position, a control unit for a separator connected to the power transformer, and a block for fixing its on position, a block for switching the output transformer protection relays to the output protection relays of the line to which the transformer is connected by a separator, as well as common for the three channels of the auto block Atiki three fixing unit relaying the action of the first, second and third transmission lines, six blocks disconnected position fixing six high-voltage circuit breakers and a time element, with each of the three channels of the switch box inputs of the first lane; of the second and second elements AND are connected respectively to the outputs of the blocks of fixation of the action of protecting the lines adjacent to the transformer, their second and third inputs are connected respectively to the outputs of the blocks of the fixation of the disconnected position of the switches adjacent to the line, their fourth inputs are connected to the output of the block of the fixation of the disconnected position of the switches, adjacent to the transformer on the side of the adjacent line, and their fifth inputs are connected to the output of the time element, their first outputs are connected to the disconnecting inputs of the control unit of the switch and the low voltage sides of the transformer, the second outputs are with the first inputs of the third and fourth AND elements, respectively, the second inputs of which are connected to the output of the off-position fixation unit, SU,, 1115163 of the low voltage side switch of the same transformer, the first outputs of the third and fourth elements AND are connected to the input of the separator control unit, their second outputs are connected to the first input of the fifth element And, the second input of which is connected to the output of the unit for fixing the on position of the separator, and the third outputs the odes of the third and fourth elements AND are connected to the input of the switching unit of the output transformer protection relays to the output protection relays of the opposite line, the first output of the fifth element And is connected to the switching input of the control unit on the low voltage side circuit breaker of the transformer, its second output with memory removal inputs the first and second elements AND, the input of the time element is connected to the outputs of the blocks fixed; situations of protection of electric / transmission lines.