CN218867906U - Voltage switching relay PT voltage loss signal loop - Google Patents

Voltage switching relay PT voltage loss signal loop Download PDF

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Publication number
CN218867906U
CN218867906U CN202222980424.1U CN202222980424U CN218867906U CN 218867906 U CN218867906 U CN 218867906U CN 202222980424 U CN202222980424 U CN 202222980424U CN 218867906 U CN218867906 U CN 218867906U
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loop
voltage
bus
relay
circuit
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陈婧华
许长清
张琳娟
张平
卢丹
郑征
周志恒
韩军伟
郭璞
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Economic and Technological Research Institute of State Grid Henan Electric Power Co Ltd
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Economic and Technological Research Institute of State Grid Henan Electric Power Co Ltd
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Abstract

The utility model belongs to the technical field of transformer substation voltage switching, in particular to a voltage switching relay PT voltage loss signal loop; the system comprises a voltage switching relay power supply loop and a PT voltage loss signal loop, wherein the voltage switching relay power supply loop comprises a first bus loop and a second bus loop, a normally open contact of a master knife switch auxiliary switch I, a first relay and a second relay are arranged on the first bus loop, and a normally open contact of a master knife switch auxiliary switch II, a third relay and a fourth relay are arranged on the second bus loop; the PT voltage-loss signal circuit comprises a first voltage-loss signal circuit and a second voltage-loss signal circuit, wherein a first normally closed contact and a first normally closed contact are arranged on the first voltage-loss signal circuit, and an A-phase breaker normally open contact, a B-phase breaker normally open contact and a C-phase breaker normally open contact are arranged on the second voltage-loss signal circuit; the utility model discloses under the circumstances such as the maintenance has a power failure, voltage switching device can't report PT decompression signal, reduces the interference to the operation personnel.

Description

Voltage switching relay PT voltage loss signal loop
Technical Field
The utility model belongs to the technical field of the voltage switching of transformer substation, concretely relates to voltage switching relay PT decompression signal return circuit.
Background
When the main wiring of the transformer substation is double-bus wiring, the corresponding transformer substation can operate on different buses at intervals, and the voltages taken by the protection device, the measurement and control device and the like are the voltages on the corresponding buses, so that the voltage switching device is required to switch the voltages; when the voltage switching relay is totally demagnetized due to some reason, such as poor contact of the disconnecting link auxiliary switch and the like, the break contact of the voltage switching relay is closed, and a PT voltage loss signal is reported at the moment; however, if a certain interval is normally overhauled, the interval breaker and the disconnecting link are disconnected, and because the disconnecting link is disconnected, a PT voltage loss signal is still reported to interfere operating personnel; therefore, it is necessary to design a PT voltage-loss signal loop of a voltage switching relay, which cannot report a PT voltage-loss signal in the case of power failure maintenance, reduces interference to operators, and reduces the workload of a manual reset signal.
SUMMERY OF THE UTILITY MODEL
The utility model aims at overcoming prior art's not enough, and provide one kind and under the circumstances such as the maintenance of having a power failure, voltage switching device can't report PT decompression signal, reduces the interference to the operation personnel, alleviates the voltage switching relay PT decompression signal return circuit of artifical reset signal work load.
The purpose of the utility model is realized like this: a voltage switching relay PT voltage loss signal loop comprises a voltage switching relay power supply loop and a PT voltage loss signal loop, wherein the voltage switching relay power supply loop comprises a first bus loop and a second bus loop, the first bus loop and the second bus loop are connected in parallel, a first bus loop is provided with a first bus auxiliary switch normally open contact, a first relay and a second relay, and a second bus loop is provided with a second bus auxiliary switch normally open contact, a third relay and a fourth relay; PT decompression signal circuit includes first decompression signal circuit and second decompression signal circuit, first decompression signal circuit with second decompression signal circuit series connection, be provided with first normally closed contact and second normally closed contact on the first decompression signal circuit, be provided with A looks circuit breaker normally open contact, B looks circuit breaker normally open contact and C looks circuit breaker normally open contact on the second decompression signal circuit, first relay with the second relay is right first normally closed contact is controlled, third relay and fourth relay are right second normally closed contact controls.
The voltage switching relay power supply circuit further comprises a first parallel circuit and a second parallel circuit, and the first bus circuit and the second bus circuit are connected in parallel through the first parallel circuit and the second parallel circuit.
The end part of the first parallel loop is provided with a first power terminal, the end part of the first bus loop is provided with a second power terminal, the end part of the first parallel loop is connected with a power supply through the first power terminal, and the end part of the first bus loop is connected with the power supply through the second power terminal.
The middle part of the first bus circuit is provided with a first intermediate terminal, and the middle part of the second bus circuit is provided with a second intermediate terminal.
The end part of the first voltage-loss signal loop is provided with a first signal loop terminal, the end part of the second voltage-loss signal loop is provided with a second signal loop terminal, and the PT voltage-loss signal loop is connected with other loops through the first signal loop terminal and the second signal loop terminal.
The first voltage-loss signal loop and the second voltage-loss signal loop are connected through a third intermediate terminal.
The utility model has the advantages that: the utility model discloses a voltage switching relay PT decompression signal circuit comprises voltage switching relay power supply circuit and PT decompression signal circuit, and voltage switching relay power supply circuit comprises I master switch auxiliary switch normally open contact 10, II master switch auxiliary switch normally open contact 3, voltage switching relay 13, 12, 5, 6; the PT voltage loss signal circuit is formed by connecting a normally closed contact 21, a normally closed contact 22, a normally open contact 15 of the A-phase circuit breaker, a normally open contact 16 of the B-phase circuit breaker and a normally open contact 17 of the C-phase circuit breaker in series;
when a certain interval normally runs on the I bus, the I bus knife switch auxiliary switch normally-open contact 10 is closed, the relays 13 and 12 act, at the moment, the normally-closed contact 21 is a dynamic break contact, the normally-closed contact 21 is broken, and the voltage switching device cannot report a PT voltage loss signal; when the contact of the normally open contact 10 of the auxiliary switch of the I main knife switch is poor, the relays 13 and 12 are demagnetized and can not act, and the normally closed contact 21 is closed; the interval runs on the I bus, the normally open contact 3 of the II bus knife switch auxiliary switch is disconnected, the relays 5 and 6 are demagnetized and cannot act, and the normally closed contact 22 is closed; because the circuit is in a normal operation state at the moment, the normally open contact 15 of the A-phase circuit breaker, the normally open contact 16 of the B-phase circuit breaker and the normally open contact 17 of the C-phase circuit breaker are in a closed state, a PT voltage loss signal loop is conducted, and a PT voltage loss signal is reported;
when a certain interval normally runs on the II bus, the normally open contact 3 of the auxiliary switch of the II bus knife switch is closed, the relays 5 and 6 act, at the moment, the normally closed contact 22 is a dynamic break contact, the normally closed contact 22 is disconnected, and the voltage switching device cannot report a PT voltage loss signal; when the contact of the normally open contact 3 of the auxiliary switch of the II main knife switch is poor, the relays 5 and 6 lose magnetism and cannot act, and the normally closed contact 22 is closed; since the interval runs in the second bus, the normally open contact 10 of the first bus knife switch auxiliary switch is disconnected, the relays 13 and 12 lose magnetism and cannot act, and the normally closed contact 21 is closed; because the normal operating state is now, A looks circuit breaker normally open contact 15, B looks circuit breaker normally open contact 16, C looks circuit breaker normally open contact 17 are the closed condition, consequently, PT decompression signal circuit switches on, reports PT decompression signal.
When one interval is in power failure maintenance, the interval breaker and the disconnecting link are in an off state at the moment; the normally open contact 10 of the first main knife switch auxiliary switch and the normally open contact 3 of the second main knife switch auxiliary switch are both opened, the relays 13, 12 and 5,6 are demagnetized and cannot move, and the normally closed contact 21 and the normally closed contact 22 are closed; because the interval circuit breaker is disconnected at the moment, the normally open contact 15 of the A-phase circuit breaker, the normally open contact 16 of the B-phase circuit breaker and the DLC normally open contact of the C-phase circuit breaker are in a disconnected state, a PT voltage loss signal loop cannot be conducted, and a PT voltage loss signal cannot be reported; the utility model discloses a voltage switching relay PT decompression signal return circuit, under the circumstances such as the maintenance has a power failure, voltage switching device can't report PT decompression signal, reduces the interference to the operation personnel, alleviates artifical reset signal work load.
Drawings
Fig. 1 is a schematic structural diagram of a power supply circuit of a voltage switching relay.
Fig. 2 is a schematic structural diagram of a PT voltage-loss signal loop.
Detailed Description
The present invention will be further described with reference to the accompanying drawings.
Examples
As shown in fig. 1-2, a voltage switching relay PT voltage-loss signal loop comprises a voltage switching relay power supply loop and a PT voltage-loss signal loop, wherein the voltage switching relay power supply loop comprises a first bus loop 9 and a second bus loop 2, the first bus loop 9 and the second bus loop 2 are connected in parallel, a first bus loop 9 is provided with a first bus knife switch auxiliary switch normally open contact 10, a first relay 13 and a second relay 12, and a second bus loop 2 is provided with a second bus knife switch auxiliary switch normally open contact 3, a third relay 5 and a fourth relay 6; PT decompression signal circuit includes first decompression signal circuit 20 and second decompression signal circuit 23, first decompression signal circuit 20 with second decompression signal circuit 23 series connection, be provided with first normally closed contact 21 and second normally closed contact 22 on the first decompression signal circuit 20, be provided with A looks circuit breaker normally open contact 15, B looks circuit breaker normally open contact 16 and C looks circuit breaker normally open contact 17 on the second decompression signal circuit 23, first relay 13 with second relay 12 is right first normally closed contact 21 controls, third relay 5 and fourth relay 6 are right second normally closed contact 22 controls.
The utility model discloses a voltage switching relay PT decompression signal circuit comprises voltage switching relay power supply circuit and PT decompression signal circuit, and voltage switching relay power supply circuit comprises I female knife-switch auxiliary switch normally open contact 10, II female knife-switch auxiliary switch normally open contact 3, voltage switching relay 13, 12, 5, 6; the PT voltage loss signal circuit is formed by connecting a normally closed contact 21, a normally closed contact 22, a normally open contact 15 of the A-phase circuit breaker, a normally open contact 16 of the B-phase circuit breaker and a normally open contact 17 of the C-phase circuit breaker in series;
when a certain interval normally runs on the I bus, the I bus knife switch auxiliary switch normally-open contact 10 is closed, the relays 13 and 12 act, at the moment, the normally-closed contact 21 is a dynamic break contact, the normally-closed contact 21 is broken, and the voltage switching device cannot report a PT voltage loss signal; when the contact of the normally open contact 10 of the auxiliary switch of the I main knife switch is poor, the relays 13 and 12 are demagnetized and can not act, and the normally closed contact 21 is closed; the interval runs in the I bus, the normally open contact 3 of the II bus knife switch auxiliary switch is disconnected, the relays 5 and 6 lose magnetism and cannot act, and the normally closed contact 22 is closed; because the circuit is in a normal operation state at the moment, the normally open contact 15 of the A-phase circuit breaker, the normally open contact 16 of the B-phase circuit breaker and the normally open contact 17 of the C-phase circuit breaker are in a closed state, a PT voltage loss signal loop is conducted, and a PT voltage loss signal is reported;
when one interval normally runs on the II bus, the normally open contact 3 of the auxiliary switch of the II bus knife switch is closed, the relays 5 and 6 act, at the moment, the normally closed contact 22 is a dynamic break contact, the normally closed contact 22 is disconnected, and the voltage switching device cannot report a PT voltage loss signal; when the contact of the normally open contact 3 of the auxiliary switch of the II main knife switch is poor, the relays 5 and 6 lose magnetism and cannot act, and the normally closed contact 22 is closed; because the interval runs on the second bus, the normally open contact 10 of the auxiliary switch of the first bus knife switch is disconnected, the relays 13 and 12 are demagnetized and cannot act, and the normally closed contact 21 is closed; because the normal operating state is now, A looks circuit breaker normally open contact 15, B looks circuit breaker normally open contact 16, C looks circuit breaker normally open contact 17 are the closed condition, consequently, PT decompression signal circuit switches on, reports PT decompression signal.
When one interval is in power failure maintenance, the interval breaker and the disconnecting link are in an off state at the moment; the normally open contact 10 of the first main knife switch auxiliary switch and the normally open contact 3 of the second main knife switch auxiliary switch are both opened, the relays 13, 12 and 5,6 are demagnetized and cannot move, and the normally closed contact 21 and the normally closed contact 22 are closed; because the interval circuit breaker is disconnected at the moment, the normally open contact 15 of the A-phase circuit breaker, the normally open contact 16 of the B-phase circuit breaker and the DLC normally open contact of the C-phase circuit breaker are all in a disconnected state, a PT voltage loss signal loop cannot be conducted, and a PT voltage loss signal cannot be reported; the utility model discloses a voltage switching relay PT decompression signal return circuit under the circumstances such as the maintenance of having a power failure, voltage switching device can't report PT decompression signal, reduces the interference to the operation personnel, alleviates artifical reset signal work load.
Examples
As shown in fig. 1-2, a voltage switching relay PT no-voltage signal loop includes a voltage switching relay power supply loop and a PT no-voltage signal loop, where the voltage switching relay power supply loop includes a first bus loop 9 and a second bus loop 2, the first bus loop 9 and the second bus loop 2 are connected in parallel, the first bus loop 9 is provided with a first bus bar switch auxiliary switch normally open contact 10, a first relay 13 and a second relay 12, and the second bus loop 2 is provided with a second bus bar switch auxiliary switch normally open contact 3, a third relay 5 and a fourth relay 6; PT decompression signal circuit includes first decompression signal circuit 20 and second decompression signal circuit 23, first decompression signal circuit 20 with second decompression signal circuit 23 series connection, be provided with first normally closed contact 21 and second normally closed contact 22 on the first decompression signal circuit 20, be provided with A looks circuit breaker normally open contact 15, B looks circuit breaker normally open contact 16 and C looks circuit breaker normally open contact 17 on the second decompression signal circuit 23, first relay 13 with second relay 12 is right first normally closed contact 21 controls, third relay 5 and fourth relay 6 are right second normally closed contact 22 controls.
For better effect, the voltage switching relay power supply loop further comprises a first parallel loop 1 and a second parallel loop 7, the first bus loop 9 and the second bus loop 2 are connected in parallel through the first parallel loop 1 and the second parallel loop 7, and the structure is simple and reasonable.
For better effect, a first power terminal 8 is provided at an end of the first parallel circuit 1, a second power terminal 14 is provided at an end of the first bus circuit 9, the end of the first parallel circuit 1 is connected to a power source through the first power terminal 8, the end of the first bus circuit 9 is connected to the power source through the second power terminal 14, and connection of each circuit to the power source is facilitated through each terminal.
For better effect, the middle part of the first bus circuit 9 is provided with a first intermediate terminal 11, the middle part of the second bus circuit 2 is provided with a second intermediate terminal 4, and the first intermediate terminal can be connected with other equipment through the intermediate terminal, so that the expandability of the circuit is improved.
For better effect, the end of the first no-voltage signal circuit 20 is provided with a first signal circuit terminal 19, the end of the second no-voltage signal circuit 23 is provided with a second signal circuit terminal 18, and the PT no-voltage signal circuit is connected with other circuits through the first signal circuit terminal 19 and the second signal circuit terminal 18, and can be conveniently connected with other circuits through each terminal.
For better effect, the first no-voltage signal circuit 20 and the second no-voltage signal circuit 23 are connected through a third intermediate terminal 24, which facilitates the connection between the circuits.
The utility model discloses a voltage switching relay PT decompression signal circuit comprises voltage switching relay power supply circuit and PT decompression signal circuit, and voltage switching relay power supply circuit comprises I female knife-switch auxiliary switch normally open contact 10, II female knife-switch auxiliary switch normally open contact 3, voltage switching relay 13, 12, 5, 6; the PT voltage loss signal circuit is formed by connecting a normally closed contact 21, a normally closed contact 22, a normally open contact 15 of the A-phase circuit breaker, a normally open contact 16 of the B-phase circuit breaker and a normally open contact 17 of the C-phase circuit breaker in series;
when a certain interval normally runs on the I bus, the I bus knife switch auxiliary switch normally open contact 10 is closed, the relays 13 and 12 act, at the moment, the normally closed contact 21 is a dynamic break contact, the normally closed contact 21 is broken, and the voltage switching device cannot report a PT voltage loss signal; when the contact of the normally open contact 10 of the auxiliary switch of the I main knife switch is poor, the relays 13 and 12 are demagnetized and can not act, and the normally closed contact 21 is closed; the interval runs in the I bus, the normally open contact 3 of the II bus knife switch auxiliary switch is disconnected, the relays 5 and 6 lose magnetism and cannot act, and the normally closed contact 22 is closed; because the circuit is in a normal operation state at the moment, the normally open contact 15 of the A-phase circuit breaker, the normally open contact 16 of the B-phase circuit breaker and the normally open contact 17 of the C-phase circuit breaker are in a closed state, a PT voltage loss signal loop is conducted, and a PT voltage loss signal is reported;
when one interval normally runs on the II bus, the normally open contact 3 of the auxiliary switch of the II bus knife switch is closed, the relays 5 and 6 act, at the moment, the normally closed contact 22 is a dynamic break contact, the normally closed contact 22 is disconnected, and the voltage switching device cannot report a PT voltage loss signal; when the contact of the normally open contact 3 of the auxiliary switch of the II main knife switch is poor, the relays 5 and 6 are demagnetized and can not act, and the normally closed contact 22 is closed; because the interval runs on the second bus, the normally open contact 10 of the auxiliary switch of the first bus knife switch is disconnected, the relays 13 and 12 are demagnetized and cannot act, and the normally closed contact 21 is closed; because the normal operating state is now, A looks circuit breaker normally open contact 15, B looks circuit breaker normally open contact 16, C looks circuit breaker normally open contact 17 are the closed condition, consequently, PT decompression signal circuit switches on, reports PT decompression signal.
When one interval is in power failure maintenance, the interval breaker and the disconnecting link are in a disconnected state at the moment; the normally open contact 10 of the first main knife switch auxiliary switch and the normally open contact 3 of the second main knife switch auxiliary switch are both open, the relays 13, 12 and 5,6 lose magnetism and cannot act, and the normally closed contact 21 and the normally closed contact 22 are closed; because the interval circuit breaker is disconnected at the moment, the normally open contact 15 of the A-phase circuit breaker, the normally open contact 16 of the B-phase circuit breaker and the DLC normally open contact of the C-phase circuit breaker are in a disconnected state, a PT voltage loss signal loop cannot be conducted, and a PT voltage loss signal cannot be reported; the utility model discloses a voltage switching relay PT decompression signal return circuit, under the circumstances such as the maintenance has a power failure, voltage switching device can't report PT decompression signal, reduces the interference to the operation personnel, alleviates artifical reset signal work load.

Claims (6)

1. The utility model provides a voltage switching relay PT decompression signal return circuit, it is including voltage switching relay power supply circuit and PT decompression signal return circuit, its characterized in that: the voltage switching relay power supply loop comprises a first bus loop (9) and a second bus loop (2), the first bus loop (9) and the second bus loop (2) are connected in parallel, an I bus knife switch auxiliary switch normally-open contact (10), a first relay (13) and a second relay (12) are arranged on the first bus loop (9), and an II bus knife switch auxiliary switch normally-open contact (3), a third relay (5) and a fourth relay (6) are arranged on the second bus loop (2); PT decompression signal circuit includes first decompression signal circuit (20) and second decompression signal circuit (23), first decompression signal circuit (20) with second decompression signal circuit (23) series connection, be provided with first normally closed contact (21) and second normally closed contact (22) on first decompression signal circuit (20), be provided with A looks circuit breaker normally open contact (15), B looks circuit breaker normally open contact (16) and C looks circuit breaker normally open contact (17) on second decompression signal circuit (23), first relay (13) with second relay (12) are right first normally closed contact (21) are controlled, third relay (5) and fourth relay (6) are right second normally closed contact (22) are controlled.
2. The voltage-loss signal loop of the voltage switching relay PT of claim 1, characterized in that: the voltage switching relay power supply circuit further comprises a first parallel loop (1) and a second parallel loop (7), and the first bus loop (9) and the second bus loop (2) are connected in parallel through the first parallel loop (1) and the second parallel loop (7).
3. The voltage-loss signal loop of the voltage switching relay PT of claim 2, characterized in that: the end part of the first parallel loop (1) is provided with a first power supply terminal (8), the end part of the first bus loop (9) is provided with a second power supply terminal (14), the end part of the first parallel loop (1) is connected with a power supply through the first power supply terminal (8), and the end part of the first bus loop (9) is connected with the power supply through the second power supply terminal (14).
4. The voltage-loss signal loop of the voltage switching relay PT of claim 1, characterized in that: a first intermediate terminal (11) is arranged in the middle of the first bus circuit (9), and a second intermediate terminal (4) is arranged in the middle of the second bus circuit (2).
5. The voltage-loss signal loop of the voltage switching relay PT of claim 1, characterized in that: the end part of the first voltage-loss signal loop (20) is provided with a first signal loop terminal (19), the end part of the second voltage-loss signal loop (23) is provided with a second signal loop terminal (18), and the PT voltage-loss signal loop is connected with other loops through the first signal loop terminal (19) and the second signal loop terminal (18).
6. The voltage-loss signal loop of the voltage switching relay PT of claim 1, characterized in that: the first voltage-loss signal circuit (20) and the second voltage-loss signal circuit (23) are connected through a third intermediate terminal (24).
CN202222980424.1U 2022-11-09 2022-11-09 Voltage switching relay PT voltage loss signal loop Active CN218867906U (en)

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Application Number Priority Date Filing Date Title
CN202222980424.1U CN218867906U (en) 2022-11-09 2022-11-09 Voltage switching relay PT voltage loss signal loop

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202222980424.1U CN218867906U (en) 2022-11-09 2022-11-09 Voltage switching relay PT voltage loss signal loop

Publications (1)

Publication Number Publication Date
CN218867906U true CN218867906U (en) 2023-04-14

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CN202222980424.1U Active CN218867906U (en) 2022-11-09 2022-11-09 Voltage switching relay PT voltage loss signal loop

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