CN110208644A - GIS cable machinery - Google Patents

Abstract

The present application discloses a GIS cable equipment, which includes T-connectors for connecting high-voltage outgoing cables one by one; Test window; the first end of the isolation device is connected to the main transformer, the second end is connected to the cable head of the high-voltage outgoing cable, and the third end is grounded; one end of the test window is used to connect the third end of the isolation device; the other end of the test window is used for Connect fault monitoring equipment. By installing a test window on the T-connector, the cable can be tested (fault detection) without degassing (GIS gas), and then after the cable fault is found, the faulty cable can be isolated through the operation of the isolation device, and the normal cable operation, greatly reducing the time and scope of power outages. The portability of line inspection and maintenance is improved, and the efficiency of fault location and isolation of T-connection lines is improved.

Description

GIS cable equipment

technical field

This application relates to the technical field of power distribution, in particular to a GIS cable device.

Background technique

The simplified wiring of high-voltage substations adopts line-transformer group wiring, and each station is finally configured with 3 main transformers and 3 power supplies, and the principle scheme that each power line "T" is connected to 3 main transformers for power supply, referred to as "3T" wiring. When the high-voltage power grid adopts the 3T wiring design, the cable T-connection is set in the substation. In order to facilitate the completion of the T-connection in the substation, it is necessary to add a GIS (Gas Insulated Switchgear, gas insulated combined electrical equipment) cable T-connector in the substation.

At present, the process of "line cable transformation and power transformation GIS transformation" of high-voltage main equipment is constantly accelerating. Neither high-voltage cables nor GIS equipment have exposed live parts. Under the maintenance mode, it is impossible to flexibly separate and isolate the working section or the fault section, which is extremely inconvenient for maintenance; and The characteristics of 3T wiring itself will lead to many sites involved in line power outages, long operation time, wide range of influence, and increased maintenance workload. There are many substations, the operation time is long, the maintenance workload is increased, and the maintenance efficiency is greatly reduced. Once a permanent fault occurs in the T-connection line of the cable, it is difficult to locate the fault. There are difficulties. The cable lines with branch joints are even more difficult to find cable faults, and the time to find faults is difficult to guarantee.

During the implementation process, the inventor found at least the following problems in the traditional technology: In the traditional high-voltage power grid using "3T" wiring, it is inconvenient to repair and maintain the line, and the fault location and isolation efficiency of the T-connected line is low.

Contents of the invention

Based on this, it is necessary to provide a GIS cable device to solve the problems of inconvenient line maintenance and low fault location and isolation efficiency of T-connected lines in the traditional high-voltage power grid using "3T" wiring.

In order to achieve the above object, the embodiment of the present invention provides a GIS cable equipment, including each T connector connected to each high-voltage outlet cable in one-to-one correspondence;

The T-joint barrel includes a barrel, an isolating device inside the barrel, and a test window on the wall of the barrel; the first end of the isolating device is connected to the main transformer, and the second end is connected to the cable head of the high-voltage outgoing cable. The three ends are grounded; one end of the test window is used to connect the third end of the isolation device; the other end of the test window is used to connect the fault monitoring equipment.

In one of the embodiments, the isolation device includes an isolation switch and a quick earthing switch;

The first end of the isolating switch is connected to the main transformer, and the second end is connected to the cable head of the high-voltage outgoing cable; one end of the quick earthing switch is connected to the second end of the isolating switch; the other end of the quick earthing switch is grounded.

In one of the embodiments, the test window comprises a conductor terminal block;

The first end of the conductor wiring board is connected to one end of the quick grounding switch; the second end of the conductor wiring board is connected to the fault monitoring equipment.

In one of the embodiments, the test window further includes a test window cover arranged on the cylinder wall of the cylinder body; a test cavity is arranged in the test window cover; and a conductor wiring board is arranged in the test cavity.

In one of the embodiments, the test window further includes a basin-type insulator for isolating the air chamber of the T-joint; the basin-type insulator is arranged in the test chamber.

In one of the embodiments, the test window further includes a post insulator; the post insulator is connected to the conductor terminal block.

In one embodiment, the isolating switch is a high voltage isolating switch.

In one of the embodiments, the main transformer is connected to two high-voltage outgoing cables respectively.

In one of the embodiments, an electrical locking device for interlocking between the circuit breaker of the main transformer and the isolating device is also included.

In one of the embodiments, the fault monitoring device is an insulation monitoring device or a fault distance measuring device.

One of the above technical solutions has the following advantages and beneficial effects:

Based on the one-to-one connection between each T connector and each high-voltage outgoing cable; the first end of the isolation device is connected to the main transformer, the second end is connected to the cable head of the high-voltage outgoing cable, and the third end is grounded; one end of the test window is used to connect to the isolation device The third end of the test window; the other end of the test window is used to connect fault monitoring equipment. By installing an isolation device in the original T-connector, the separation between the T-connector cables and the main circuit can be realized; by installing a test window on the T-connector, it is possible to realize that there is no need to deflate (GIS gas) Test the cable (fault detection), and then realize that after the cable fault is found, the faulty cable can be isolated through the operation of the isolation device, and the normal cable operation can greatly reduce the power failure time and scope. The portability of line inspection and maintenance is improved, and the efficiency of fault location and isolation of T-connection lines is improved.

Description of drawings

Fig. 1 is the first structural representation of GIS cable equipment in an embodiment;

Fig. 2 is the second structural representation of GIS cable equipment in an embodiment;

Fig. 3 is a schematic diagram of the structure of the test window in one embodiment.

Detailed ways

In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. A preferred embodiment of the application is shown in the drawings. However, the present application can be embodied in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of this application more thorough and comprehensive.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of the invention. The terms used herein in the description of the present invention are for the purpose of describing specific embodiments only, and are not intended to limit the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In the traditional high-voltage power grid using "3T" wiring, the 110kV main equipment "line cable and substation GIS" process continues to accelerate, the 110kV high-voltage cable and GIS equipment have no exposed live parts, and there is no gap between the two parallel 110kV outgoing lines. If any fault isolation device is installed, it is impossible to flexibly separate and isolate the working section or the fault section in the maintenance mode, and the maintenance is extremely inconvenient; and the characteristics of the 3T wiring itself will cause the power outage of the line to involve many stations, the operation time is long, and the scope of influence is wide, which requires more maintenance. workload. For example, if one or two 110kV lines lose power, one or two main transformers in each of the three 110kV substations will lose power. Requirements, there are 4 to 5 substations involved in 110kV line operation or 110kV equipment start-up charging, 8 to 10 operators are required, and more 110kV substations (generally 3) need to be contacted. Therefore, when the line fails, the scope of inspection and the time for fault finding are greatly increased. When the line is routinely powered off for maintenance, many substations are involved, the operation time is long, and the maintenance workload is increased. And if the main line is a double-circuit or four-circuit common tower, 6 power outage operations are required when the line is transformed into a pole and tower, which is 4 times more than the double-circuit chain connection, which greatly reduces maintenance efficiency.

In addition, since there is no fault isolation or measuring device between the two parallel 110kV outgoing lines, once a permanent fault occurs in the T-connection line of the cable, it is difficult to locate the fault, and it is difficult to untie the T-connector, and it is impossible to quickly remove the faulty section, which takes a long time to repair; The fault location of the cable line has the phenomena of chaotic pulse signal and difficulty in judging the fault point, which makes it difficult to locate the fault. The cable lines with branch joints are even more difficult to find cable faults, and the time to find faults is difficult to guarantee. There is a large workload for fault location of the T-connection line, and it takes a long time to repair the accident, and the fault removal of the existing T-connection line depends on the outgoing line circuit breaker in the 220kV substation on the power supply side. There is a possibility that the scope of the power outage will be extended.

In the traditional high-voltage power grid using "3T" wiring, once a permanent fault occurs in the line, it is impossible to quickly determine and remove the faulty section, and all lines need to be powered off, which has a large impact range. In addition, the T connector is difficult to disconnect, which makes it difficult to locate the fault, especially when the three terminals are all GIS terminals, the GIS terminal needs to be deflated and disassembled before the fault location test can be performed, which takes a lot of manpower, material resources and time; The more, the more complex the waveform of the traveling wave method becomes, increasing the difficulty and time of fault finding.

And in the GIS cable equipment provided by the application, the separation between the T-connection cables can be realized by adding an isolating device in the original T-connector; GIS gas) can test the cable (fault detection), and then realize that after the cable fault is found, the faulty cable can be isolated through the operation of the isolation device, and the normal cable operation can greatly reduce the power failure time and scope. The portability of line inspection and maintenance is improved, and the efficiency of fault location and isolation of T-connection lines is improved.

In one embodiment, as shown in FIG. 1 , a GIS cable device is provided, including T-connectors 120 connected to high-voltage outgoing cables 110 in one-to-one correspondence.

The T-connector 120 includes a cylinder body 122, an isolating device 124 disposed in the cylinder body 122, and a test window 126 disposed on the wall of the cylinder body 122; the first end of the isolating device 124 is connected to the main transformer 130, and the second end Connect the cable end of the high-voltage outlet cable 110 , and ground the third end; one end of the test window 126 is used to connect the third end of the isolation device 124 ; the other end of the test window 126 is used to connect the fault monitoring device 140 .

Among them, the T-connection barrel 120 refers to the sulfur hexafluoride gas-insulated high-voltage power distribution device used for the T-connection line; the T-connection line refers to a line connected from the middle of the line supplying power from Party A to Party B in the high-voltage power supply, Supply power to third parties. The high-voltage outgoing cable 110 refers to the high-voltage outgoing line used to connect to the busbar of the substation. For example, the high voltage outgoing cable 110 may be a 110 kV outgoing cable. The cable end refers to the cable connector at the end of the high-voltage outgoing cable. The cylinder 122 can be a metal cylinder, and there is an air chamber inside the cylinder 122. The air chamber can be used to set the isolating switch, the busbar of the grounding switch, the connector and the outlet terminal, etc.; SF6 (sulfur hexafluoride) gas is used as insulation and arc extinguishing medium. The isolating device 124 can be used to disconnect and isolate the high-voltage outgoing cable in the T-connector when the line fails. Fault monitoring equipment 140 may be used to monitor line faults; test window 126 refers to an intermediate device for connecting the fault monitoring equipment on the ground side of the isolator. The main transformer 130 refers to a general step-down transformer mainly used for power transmission and transformation in a unit or a substation.

Specifically, in a high-voltage power grid system with "3T" wiring (such as a 110kV power grid system), the wiring form of the substation is in the form of a line to a transformer group, and the outgoing line is the cable outgoing line of the T-connector, that is, each T-connector 120 and each high-voltage outgoing line The cables 110 are connected in one-to-one correspondence. Connect the main transformer 130 by the first end of the isolating device 124, the second end of the isolating device 124 connects the cable head of the high-voltage outlet cable 110, and the third end of the isolating device 124 is grounded; one end of the test window 126 can be used to connect the The third end; the other end of the test window 126 can be used to connect a fault monitoring device 140 . When the grid system is in normal operation, the first end of the isolation device 124 is connected to the second end of the isolation device 124, and the third end of the isolation device 124 is disconnected, that is, the high-voltage outgoing cable 110 is conducted, so that the main transformer 130 Electricity can be transmitted to the busbars through high voltage outgoing cables 110 . When the power grid system fails, the first end of the isolation device 124 is disconnected from the second end of the isolation device 124, and the third end of the isolation device 124 is connected to the ground; that is, the high-voltage outgoing cable 110 is disconnected and close to the bus side The high-voltage outgoing cable 110 is grounded, and the entire section of the line is out of service and the main transformer 130 is out of service to prevent accidents such as line leakage.

When the power grid system fails and enters the maintenance state, the test window 126 can be opened, and then the fault monitoring device 140 can transmit a test voltage signal to the high-voltage outlet cable 110 through the test window 126 for testing; the fault monitoring device 140 can further perform tests according to the test results. Realizing the faulty line and the corresponding position of the faulty line, it is not necessary to deflate and inflate the entire T-joint 120 , which simplifies the test procedure and makes the test fast and convenient. After the fault line test is completed, conduction is conducted between the first end of the isolating device 124 on the normal high-voltage outlet cable and the second end of the isolating device 124, and the third end of the isolating device 124 is disconnected, that is, the normal line resumes power supply; The first end of the isolation device 124 on the faulty high-voltage outgoing cable is disconnected from the second end of the isolation device 124, and the third end of the isolation device 124 is connected to ground, that is, the faulty line remains isolated and disconnected, and the main transformer 130 recovers. Power supply, greatly reducing the power outage time and power outage scope.

Furthermore, after a fault occurs on a line, the power transmission station must first conduct an insulation test on the relevant line, and if the insulation is damaged, it is the faulty line. Carry out a withstand voltage test on the faulty line, that is, fault detection to find out the fault point. By opening the test window 126, the fault monitoring device 140 can test the high-voltage outgoing cable 110 through the test window 126, so that insulation monitoring and fault finding tests can be performed without inflation and deflation. After quickly finding the fault point through the test window 126, the additional isolation device 124 can be used to disconnect the fault line for maintenance, and at the same time restore the power transmission of the main transformer 130 in the T-connection line, which greatly reduces the power outage time of the substation.

In an example, the fault monitoring device 140 can output a 10 kV DC pulse voltage signal to the high voltage outgoing cable for test monitoring.

It should be noted that the isolation device 124 is arranged in the air chamber of the barrel, and the test window 126 is arranged outside the air chamber of the barrel, that is, the test window 126 is separated from the air chamber of the T-joint 120 .

In the above-mentioned GIS cable equipment, each T connector is connected to each high-voltage outgoing cable in one-to-one correspondence; the sixth end of the isolation device is connected to the main transformer, the second end is connected to the cable head of the high-voltage outgoing cable, and the third end is grounded; the test window One end is connected to the third end of the isolation device; the other end of the test window is used to connect the fault monitoring equipment. By installing an isolation device in the original T-joint barrel, the separation between the T-joint cables can be realized; by installing a test window on the T-joint barrel, the cable can be tested without degassing (GIS gas) (fault Detection), and then realize that after the cable fault is found, the faulty cable can be isolated through the operation of the isolation device, and the normal cable operation can greatly reduce the power failure time and scope. The portability of line inspection and maintenance is improved, and the efficiency of fault location and isolation of T-connection lines is improved.

In a specific embodiment, as shown in FIG. 1 , the main transformer 130 is respectively connected to two high-voltage outgoing cables 110 .

Specifically, the main transformer 130 has two high-voltage outgoing cables 110, and the two high-voltage outgoing cables 110 are arranged side by side. Each high-voltage outgoing cable 110 is connected to the bus bar through a cable head. For example, the main transformer 130 has two 110kV outgoing cables, and the two 110kV outgoing cables are arranged side by side. Each 110kV outgoing cable is connected to the 110kV bus through the cable head. By installing an isolating device 124 on the high-voltage outgoing cable 110 in the T-connector 120, the separation between the T-connected cables is realized, and then when the cable fails, the test window 126 is opened, and the fault monitoring device 140 is used for fault monitoring. Faulty cables can be detected. After quickly finding the fault point through the test window 126, the fault line can be disconnected for maintenance, and the power supply of the main transformer can be restored at the same time, which greatly reduces the power outage time of the substation.

Further, as shown in FIG. 2 , three main transformers 130 may be included in the 3T wiring line, and each main transformer 130 has two high-voltage outgoing cables 110 .

In one embodiment, as shown in FIG. 1 , a GIS cable device is provided, and the isolation device 124 includes an isolation switch 222 and a quick grounding switch 224 . The first end of the isolating switch 222 is connected to the main transformer 130, and the second end is connected to the cable head of the high-voltage outgoing cable 110; one end of the quick earthing switch 224 is connected to the second end of the isolating switch 222; the other end of the quick earthing switch 224 is grounded.

Wherein, the isolating switch 222 can be used to ensure the safety of the high-voltage electrical appliances and devices during maintenance work, and play the role of isolating voltage; for example, the isolating switch 222 can be a high-voltage isolating switch. The fast earthing switch 224 refers to a special-purpose earthing switch with a certain closing short-circuit current capability.

Specifically, based on the first end of the isolating switch 222 connected to the main transformer 130, the second end of the isolating switch 222 is connected to the cable head of the high-voltage outgoing cable 110; one end of the quick earthing switch 224 is connected to the second end of the isolating switch 222; the quick earthing switch The other end of 224 is grounded. When the grid system is running normally, the isolating switch 222 is closed and the fast earthing switch 224 is opened, that is, the high-voltage outgoing cable 110 is turned on, so that the power of the main transformer 130 can be transmitted to the bus through the high-voltage outgoing cable 110 . When the grid system fails, the isolating switch 222 is opened and the fast grounding switch 224 is closed; that is, the high-voltage outgoing cable 110 is disconnected, and the entire line and the main transformer 130 are out of service. When the power grid system fails and enters the maintenance state, the test window 126 can be opened, and then the fault monitoring device 140 can transmit a test voltage signal to the high-voltage outlet cable 110 through the test window 126 for testing; the fault monitoring device 140 can further perform tests according to the test results. Realizing the faulty line and the corresponding position of the faulty line, it is not necessary to deflate and inflate the entire T-joint 120 , which simplifies the test procedure and makes the test fast and convenient. After the faulty line test is completed, the isolating switch 222 on the normal high-voltage outgoing cable is closed, and the fast grounding switch 224 is disconnected, that is, the normal line resumes power supply; Closed, that is, the fault line remains isolated and disconnected, and the main transformer 130 restores power supply, which greatly reduces the power outage time and power outage range.

In the above-mentioned GIS cable equipment, the separation between the T-connection cables is realized by installing an isolation switch and a quick grounding switch in the original T-connector; Gas) can test the cable (fault detection), and then realize that after the cable fault is found, the faulty cable can be isolated through the operation of the isolation device, and the normal cable operation can greatly reduce the power failure time and scope. The portability of line inspection and maintenance is improved, and the efficiency of fault location and isolation of T-connection lines is improved.

In a specific embodiment, the fault monitoring device is an insulation monitoring device or a fault distance measuring device.

Wherein, the insulation monitoring device refers to a device for detecting the insulation state of the power cable. Fault location equipment refers to the equipment used for fault location of power cables. The insulation monitoring equipment is connected to the grounding side of the isolation device through the test window, and then the insulation monitoring equipment can perform insulation detection on the corresponding high-voltage outgoing cable. If the insulation damage of the high-voltage outgoing cable is detected, it is judged that the high-voltage outgoing cable is a faulty line. The fault location equipment is connected to the ground side of the isolation device through the test window, and then the fault location equipment can perform withstand voltage tests on the fault line, and find out the fault point through fault detection. Further, the line insulation monitoring and fault detection test can be carried out without inflation and deflation, and the efficiency of fault location and isolation of the T-connection line is improved.

In one embodiment, as shown in FIG. 3 , the test window 126 includes a conductor wiring board 232; a first end of the conductor wiring board 232 is connected to one end of the quick earthing switch 224; a second end of the conductor wiring board 232 is connected to the fault monitoring device 140 .

Wherein, the conductor wiring board 140 can be used to connect the fault monitoring equipment 140 and the fast grounding switch 224; the conductor wiring board 140 can be a three-phase conductor wiring board.

Specifically, the first end of the conductor wiring board 140 can be fixedly connected to one end of the quick grounding switch; the second end of the conductor wiring board 232 can be plugged into the fault monitoring device 140 . When the power grid system enters the maintenance state after a fault occurs, the test window 126 can be opened, and the fault monitoring device 140 can be plugged into the conductor terminal board 232, and then the fault monitoring device 140 can transmit the test to the high-voltage outgoing cable 110 through the conductor terminal board 232. The voltage signal is tested; the fault monitoring equipment 140 can realize the faulty line and the corresponding position of the faulty line according to the test results, without deflation and inflation of the entire T-connector, which simplifies the test process and makes the test fast and convenient.

In a specific embodiment, the test window further includes a test window cover arranged on the cylinder wall of the cylinder body; a test cavity is arranged in the test window cover; and a conductor wiring board is arranged in the test cavity.

Specifically, the test cavity can be arranged in the barrel, and the test cavity and the air chamber in the barrel are sealed and isolated from each other, so that when the circuit is tested, there is no need to deflate the T-connector, and the test is quick and convenient. The test window cover is movably connected with the cylinder wall of the cylinder body. When the power grid system fails and enters the maintenance state, the test window cover can be opened, and then the fault monitoring equipment can be plugged into the conductor terminal board for test monitoring.

In a specific embodiment, as shown in FIG. 3 , the test window 126 further includes a pot insulator 234 for isolating the air chamber of the T-joint; the pot insulator 234 is arranged in the test cavity.

Specifically, the basin-type insulator 234 can be arranged in the test cavity to isolate the air chamber of the T-joint and play a sealing role.

Further, as shown in FIG. 3 , the test window 126 further includes a post insulator 236 ; the post insulator 236 is connected to the conductor wiring board 232 . Specifically, post insulator 236 refers to an insulating control. Based on the fact that the post insulator 236 is connected to the conductor wiring board 232, the creepage distance can be increased and the safety performance of the test window can be improved.

In one embodiment, an electrical blocking device for interlocking between the circuit breaker of the main transformer and the isolating device is also included.

Among them, the electrical locking device can be used to connect the auxiliary contacts of equipment such as circuit breakers and isolating devices (isolating switches and quick earthing switches) to the operating power circuits of related electrical equipment to form a locking. Electrical interlocking devices can be used only to prevent misoperation of circuit breakers and isolating devices (disconnectors and quick earthing switches).

Specifically, the circuit breaker is connected between the output terminal of the main transformer and the high-voltage outgoing cable. By installing an electrical locking device, the interlock between the circuit breaker and the isolating device can be realized to prevent misoperation of the isolating switch and the fast earthing switch. Then the safety performance of the T-joint is improved.

The various technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the various technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only represent several implementation modes of the present application, and the description thereof is relatively specific and detailed, but it should not be construed as limiting the scope of the patent for the invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the scope of protection of the patent application should be based on the appended claims.

Claims (10)

1. A kind of GIS cable equipment, is characterized in that, comprises each T socket that connects each high-voltage outlet cable in one-to-one correspondence respectively; The T-connector includes a cylinder, an isolating device disposed in the cylinder, and a test window disposed on the wall of the cylinder; the first end of the isolating device is connected to the main transformer, and the second end is connected to the The third end of the cable head of the high-voltage outlet cable is grounded; one end of the test window is used to connect to the third end of the isolation device; the other end of the test window is used to connect to fault monitoring equipment. 2. The GIS cable equipment according to claim 1, wherein the isolation device comprises an isolation switch and a quick grounding switch; The first end of the isolating switch is connected to the main transformer, and the second end is connected to the cable head of the high-voltage outgoing cable; one end of the fast earthing switch is connected to the second end of the isolating switch; The other end is grounded. 3. The GIS cable equipment according to claim 2, wherein the test window comprises a conductor terminal block; The first end of the conductor wiring board is connected to one end of the quick grounding switch; the second end of the conductor wiring board is connected to the fault monitoring equipment. 4. The GIS cable device according to claim 3, wherein the test window also includes a test window cover arranged on the wall of the cylinder; the test window cover is provided with a test cavity; The conductor wiring board is arranged in the test chamber. 5. The GIS cable equipment according to claim 4, wherein the test window further comprises a pot insulator for isolating the air chamber of the T-joint; The pot insulator is arranged in the test chamber. 6. The GIS cable equipment according to claim 4, wherein the test window also includes a post insulator; The post insulator is connected to the conductor terminal block. 7. The GIS cable equipment according to claim 1, characterized in that the isolating switch is a high-voltage isolating switch. 8. The GIS cable equipment according to claim 1, characterized in that, the main transformer is respectively connected to two of the high-voltage outgoing cables. 9. The GIS cable equipment according to any one of claims 1 to 8, further comprising an electrical locking device for interlocking between the circuit breaker of the main transformer and the isolating device. 10. The GIS cable equipment according to any one of claims 1 to 8, characterized in that the fault monitoring equipment is insulation monitoring equipment or fault distance measuring equipment.