CN113991616B - Bus protection equipment replacement method based on double bus wiring mode - Google Patents

Abstract

A method for replacing busbar protection equipment based on double-busbar wiring. According to the principle of dual configuration of relay protection, the busbar protection equipment is composed of protection device I and protection device II. The new protection device is installed in a different place. Replacement protection device, under the condition that the busbar protection equipment is not powered off, when replacing the protection device I, combined with the power failure of each circuit on the busbar, the relevant circuits of the corresponding lines, namely the current circuit, failure circuit, tripping circuit and knife switch position circuit, respectively carry out transition , When the protection device II is replaced, each circuit on the bus will not be powered off, only the electrified transition failure circuit; so that the bus protection equipment can complete the replacement of the double protection of the bus without power failure.

Description

A method for replacing busbar protection equipment based on double busbar wiring mode

technical field

The invention belongs to the technical field of substation wiring, and relates to a method for replacing busbar protection equipment based on a double busbar wiring mode.

Background technique

At present, the protection operation period of the substation is 15 years. According to the operation requirements of the power grid, in order to ensure the reliability of the power supply equipment, the protection device needs to be replaced after the operation period is reached. When the conventional line protection is replaced, only the corresponding line is powered off. The operation mode of electricity will not be greatly affected, and the load transmission will not cause too much loss; but in the double-bus connection mode, the replacement of bus protection equipment is a big challenge for substations. Bus protection equipment is a guarantee It is an important system equipment for the safe and stable operation of the power grid. Its safety, reliability, sensitivity and rapidity are of decisive significance to ensure the safety of the entire regional power grid. Therefore, it is very necessary to set up bus protection equipment with reliable action and good performance so that it can quickly detect the fault of the bus and remove the fault in time and selectively. If the bus on the high-voltage side of the substation adopts the double-bus connection mode, when the protection of the bus needs to be replaced, the lines carried by the two buses need to be powered off, which means that the entire substation is in a power outage, which has a negative effect on the operation of the power grid. Great impact: the complete shutdown of the terminal substation may cause load loss and interrupt the power supply to some power users; the complete shutdown of the hub substation will cause the system to lose many important circuit connection lines, and at the same time cause multiple low The voltage level substations were completely shut down, causing large-scale power outages.

Contents of the invention

purpose of invention

The invention aims at the double-bus connection mode of the high-voltage side bus in the substation. When the bus protection needs to be replaced, the lines carried by the two bus bars need to be powered off, causing large-area or all power outage accidents, and provides a dual-bus connection mode. Replacement method of busbar protection equipment.

Technical solutions

The bus protection equipment and the branch lines on the bus are equipped with multiple secondary circuits, which are: current circuit, start-up failure circuit, trip circuit, and knife switch position circuit;

Current loop: the current collected by the busbar protection equipment is taken from the current transformers of each line on the busbar;

Start-up failure circuit: The start-up failure binary input collected by the busbar protection equipment is taken from the circuit breaker failure box in each line protection;

Tripping circuit: the tripping output output by the busbar protection equipment acts on the split-phase operation box in each line protection device;

Knife switch position circuit: the line knife switch position binary input required by the bus protection equipment is taken from the voltage switching box of each line protection device;

Replacement of protection devices for busbar protection: the connection of the above four circuits transitions from the old protection state to the new protection state, and the transition process includes four stages:

1) Old protection stage:

Old busbar protection equipment includes: old busbar differential protection device I, old busbar differential protection device II and old busbar failure protection device;

The connection between the old busbar differential protection device I and each line has a current loop MA1 taken from the outdoor terminal box downstream of the line current transformer, a tripping loop MT1 acting on the phase separation operation box in each line protection, and a knife switch position loop ML1 taken from Voltage switching box for each line protection;

The connection between the old busbar differential protection device II and each line has a current loop MA2 taken from the outdoor terminal box downstream of the line current transformer, a tripping loop MT2 acting on the phase separation operation box in each line protection, and a knife switch position loop ML2 taken from Voltage switching box for each line protection;

The connection between the old bus failure protection device and each line has a trip circuit ST1 acting on the split-phase operation box in each line protection device, a trip circuit ST2 acting on the split-phase operation box in each line protection device, and the knife position circuit SL is taken from The voltage switching box of each line protection device; the starting failure circuit SQ is taken from the circuit breaker failure box in each line protection device;

When the following transition stages are realized, the live line and live devices on the line shall be isolated by insulating medium.

2) The first transition stage:

The busbar protection equipment in the first transition stage includes: new busbar differential and failure protection device I, old busbar differential protection device II and old busbar failure protection device;

The old busbar differential protection device I in the old protection stage is out of service, combined with the power outage of each line one by one, the current loop MA1, tripping circuit MT1, and knife position loop ML1 are transferred from the old busbar protection device in the old protection stage to the new busbar protection device , increase the start-up failure circuit SQ1 from each line protection device; the new bus differential and failure protection device I at this stage is operated by the old bus differential protection device II and the old bus failure protection device before the complete transition is completed;

3) The second transition stage:

The busbar protection equipment in the second transition stage includes: new busbar differential and failure protection device I and new busbar differential and failure protection device II;

The second transition stage is: the old busbar differential protection device II and the old busbar failure protection device are out of service, each line is not powered off, and the current loop MA2, tripping loop MT2, tripping loop ST1, tripping loop ST2, and knife position loop ML2 are connected The old busbar protection device in the old protection stage is transitioned to the new busbar protection device, the start-up failure circuit SQ and the knife position circuit SL in the old protection stage are removed, and the start-up failure circuit SQ2 is added from each line protection device; the new busbar differential at this stage And the failure protection device I has been put into operation; the new bus differential and failure protection device II will be operated by the new bus differential and failure protection device I before the complete transition is completed;

4) The replacement completes the protection stage:

The replacement of the bus equipment in the protection stage is as follows: the new bus differential and failure protection device I, the new bus differential and failure protection device II have been put into operation, and the replacement of the protection stage is completed.

Advantages and effects

Simplify the working process, the method is simple and easy, save working time, improve work efficiency; do not require the bus to stop completely, ensure the reliability of power supply; ensure the safety of people and equipment, and meet the needs of maximizing system operation.

Description of drawings

Fig. 1 is a schematic diagram of the old protection stage of the present invention; (a) is a schematic diagram of the loop wiring of the old bus differential protection device I, (b) is a schematic diagram of the loop wiring of the old bus differential protection device II, and (c) is a failure of the old bus Schematic diagram of the circuit wiring of the protection device;

Fig. 2 is the schematic diagram of the first transition stage of the present invention; (a) is the circuit wiring schematic diagram of new bus differential and failure protection device I, (b) is the circuit wiring schematic diagram of old bus differential protection device II, (c) is Schematic diagram of the circuit wiring of the old busbar failure protection device;

Fig. 3 is the second transition stage schematic diagram of the present invention; (a) is the circuit wiring schematic diagram of new bus differential and failure protection device I, (b) is the circuit wiring schematic diagram of new bus differential and failure protection device II, (c ) is the circuit wiring diagram of the removed old bus differential protection device II, and (d) is the circuit wiring diagram of the removed old bus failure protection device;

Figure 4 is a schematic diagram of the replacement protection stage; (a) is a schematic diagram of the circuit wiring of the new bus differential and failure protection device I, and (b) is a schematic diagram of the circuit wiring of the new bus differential and failure protection device II.

Detailed ways

Below in conjunction with accompanying drawing, the present invention will be further described:

According to the dual configuration principle of relay protection, the busbar protection equipment is composed of protection device I and protection device II. The new protection device is installed in a different place. When replacing the old busbar protection equipment, replace the protection devices one by one. , When replacing the protection device I, combined with the power failure of each circuit on the bus, the relevant circuits of the corresponding line, namely the current circuit, failure circuit, trip circuit and knife switch position circuit, respectively make transitions, and when the protection device II is replaced, each circuit on the bus is not powered off. Only live transition failure circuit; so that the busbar protection equipment can complete the replacement of the busbar double protection without power failure;

The new protection device is installed in a different place. When replacing the busbar protection equipment, the protection device is replaced one by one. The busbar is not powered off. When the protection device I is replaced, the power of each circuit on the busbar is cut off. Isolation measures should be taken after the switch position circuits are transitioned in, during which the old failure protection device will not be returned; when the protection device II is replaced, all circuits on the bus will not be powered off, and only the power transition failure circuit will be charged.

Example

The bus protection equipment and the branch lines on the bus are equipped with multiple secondary circuits, which are: current circuit, start-up failure circuit, trip circuit, and knife switch position circuit;

Current loop: the current collected by the busbar protection equipment is taken from the current transformers of each line on the busbar;

Start-up failure circuit: The start-up failure binary input collected by the busbar protection equipment is taken from the circuit breaker failure box in each line protection;

Tripping circuit: the tripping output output by the busbar protection equipment acts on the split-phase operation box in each line protection device;

Knife switch position circuit: the line knife switch position binary input required by the bus protection equipment is taken from the voltage switching box of each line protection device;

Replacement of protection devices for busbar protection: the connection of the above four circuits transitions from the old protection state to the new protection state, and the transition process includes four stages:

1) Old protection stage:

As shown in Figure 1:

Old busbar protection equipment includes: old busbar differential protection device I, old busbar differential protection device II and old busbar failure protection device;

The connection between the old busbar differential protection device I and each line has a current loop MA1 taken from the outdoor terminal box downstream of the line current transformer, a tripping loop MT1 acting on the phase separation operation box in each line protection, and a knife switch position loop ML1 taken from Voltage switching box for each line protection;

The connection between the old busbar differential protection device II and each line has a current loop MA2 taken from the outdoor terminal box downstream of the line current transformer, a tripping loop MT2 acting on the phase separation operation box in each line protection, and a knife switch position loop ML2 taken from Voltage switching box for each line protection;

The connection between the old bus failure protection device and each line has a trip circuit ST1 acting on the split-phase operation box in each line protection device, a trip circuit ST2 acting on the split-phase operation box in each line protection device, and the knife position circuit SL is taken from The voltage switching box of each line protection device; the starting failure circuit SQ is taken from the circuit breaker failure box in each line protection device;

2) The first transition stage:

as shown in picture 2:

The busbar protection equipment in the first transition stage includes: new busbar differential and failure protection device I, old busbar differential protection device II and old busbar failure protection device;

The old busbar differential protection device I in the old protection stage is out of service, combined with the power outage of each line one by one, the current loop MA1, tripping circuit MT1, and knife position loop ML1 are transferred from the old busbar protection device in the old protection stage to the new busbar protection device , increase the start-up failure circuit SQ1 from each line protection device; the new bus differential and failure protection device I at this stage is operated by the old bus differential protection device II and the old bus failure protection device before the complete transition is completed;

3) The second transition stage:

As shown in Figure 3:

The busbar protection equipment in the second transition stage includes: new busbar differential and failure protection device I and new busbar differential and failure protection device II;

The second transition stage is: the old busbar differential protection device II and the old busbar failure protection device are out of service, each line is not powered off, and the current loop MA2, tripping loop MT2, tripping loop ST1, tripping loop ST2, and knife position loop ML2 are connected The old busbar protection device in the old protection stage is transitioned to the new busbar protection device, the start-up failure circuit SQ and the knife position circuit SL in the old protection stage are removed, and the start-up failure circuit SQ2 is added from each line protection device; the new busbar differential at this stage And the failure protection device I has been put into operation; the new bus differential and failure protection device II will be operated by the new bus differential and failure protection device I before the complete transition is completed;

4) The replacement completes the protection stage:

As shown in Figure 4:

The replacement of the bus equipment in the protection stage is as follows: the new bus differential and failure protection device I, the new bus differential and failure protection device II have been put into operation, and the replacement of the protection stage is completed.

When the transition stage is realized, the insulating medium is used to isolate the live line and the live device on the line.

Safe operation of the present invention:

1. After the new bus protection device is connected to the first branch line, remove all the outlets and functional pressure plates on the protection device, disconnect the tripping circuit connection of the terminal block, insert the insulating partition, and insulate the connected branch line with red Seal it with tape to prevent touching it;

2. Before the second branch line starts to work, it is necessary to ensure that the isolation measures of the connected branch lines on the protection device are complete.

Claims (4)

1. A method for replacing busbar protection equipment based on double-busbar wiring, characterized in that: the busbar protection is replaced by the following four stages: 1) Old protection stage: Old busbar protection equipment includes: old busbar differential protection device I, old busbar differential protection device II and old busbar failure protection device; The connection between the old busbar differential protection device I and each line has a current loop MA1 taken from the outdoor terminal box downstream of the line current transformer, a tripping loop MT1 acting on the phase separation operation box in each line protection, and a knife switch position loop ML1 taken from Voltage switching box for each line protection; The connection between the old busbar differential protection device II and each line has a current loop MA2 taken from the outdoor terminal box downstream of the line current transformer, a tripping loop MT2 acting on the phase separation operation box in each line protection, and a knife switch position loop ML2 taken from Voltage switching box for each line protection; The connection between the old bus failure protection device and each line has a trip circuit ST1 acting on the split-phase operation box in each line protection device, a trip circuit ST2 acting on the split-phase operation box in each line protection device, and the knife position circuit SL is taken from The voltage switching box of each line protection device; the starting failure circuit SQ is taken from the circuit breaker failure box in each line protection device; 2) The first transition stage: The busbar protection equipment in the first transition stage includes: new busbar differential and failure protection device I, old busbar differential protection device II and old busbar failure protection device; The old busbar differential protection device I in the old protection stage is out of service, combined with the power outage of each line one by one, the current loop MA1, tripping circuit MT1, and knife position loop ML1 are transferred from the old busbar protection device in the old protection stage to the new busbar protection device , increase the start-up failure circuit SQ1 from each line protection device; the new bus differential and failure protection device I at this stage is operated by the old bus differential protection device II and the old bus failure protection device before the complete transition is completed; 3) The second transition stage: The busbar protection equipment in the second transition stage includes: new busbar differential and failure protection device I and new busbar differential and failure protection device II; The second transition stage is: the old busbar differential protection device II and the old busbar failure protection device are out of service, each line is not powered off, and the current loop MA2, tripping loop MT2, tripping loop ST1, tripping loop ST2, and knife position loop ML2 are connected The old bus protection device in the old protection stage is transitioned to the new bus protection device, the start-up failure circuit SQ and the knife position circuit SL in the old protection stage are removed, and the start-up failure circuit SQ2 is added from each line protection device; at this stage, the new busbar differential And the failure protection device I has been put into operation; the new bus differential and failure protection device II will be operated by the new bus differential and failure protection device I before the complete transition is completed; 4) The replacement completes the protection stage: The replacement of the bus equipment in the protection stage is as follows: the new bus differential and failure protection device I, the new bus differential and failure protection device II have been put into operation, and the replacement of the protection stage is completed. 2. The method for replacing busbar protection equipment based on double-busbar connection according to claim 1, characterized in that: when realizing the transition stage, an insulating medium is used to isolate the live line and the live device on the line. 3. The method for replacing busbar protection equipment based on double-busbar wiring according to claim 1, characterized in that: the replacement of the protective device for busbar protection includes the connection of the current loop, the startup failure loop, the trip loop and the switch position loop from the old The protection state transitions to a new protection state. 4. The method for replacing busbar protection equipment based on double busbar wiring according to claim 1, characterized in that: the busbar protection equipment and the branch lines on the busbar are provided with multiple secondary circuits, which are respectively: current loop, start-up failure circuit, trip circuit, knife switch position circuit; Current loop: the current collected by the busbar protection equipment is taken from the current transformers of each line on the busbar; Start-up failure circuit: The start-up failure binary input collected by the busbar protection equipment is taken from the circuit breaker failure box in each line protection; Tripping circuit: the tripping output output by the busbar protection equipment acts on the split-phase operation box in each line protection device; Knife switch position loop: The line switch position binary input required by the busbar protection equipment is taken from the voltage switch box of each line protection device.

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