CN115542093A - A direct connection structure between the head end of GIL and the cable in the underground pipe gallery and its pressure test method - Google Patents

Abstract

The embodiment of the present application provides a direct connection structure between the head end of the GIL and the cable in the underground pipe gallery and its withstand voltage test method. The conductive component, the tee unit and the GIL three-phase phase-splitting unit are arranged in the underground pipe gallery Inside, the first feeding port and the second feeding port are arranged on the underground pipe gallery, the conductive component is connected to the three-way unit, and the three-way unit is connected to the GIL three-phase phase-splitting unit. In the embodiment of this application, the GIL and the cable are installed in place at one time. Without disassembling the cable terminal, remove the detachable conductor at the end of the GIL main circuit in the terminal housing to form an electrical isolation fracture, and at the same time pass the transition tee between the GIL and the cable terminal. The test interface reserved by the unit is used to connect to the GIL withstand voltage equipment, and finally realize the on-site withstand voltage test of GIL alone, effectively reducing the cross-waiting period of the installation process of GIL and cables.

Description

A direct connection structure between the head end of GIL and the cable in the underground pipe gallery and its withstand voltage test method

technical field

The embodiments of the present application belong to the field of electric power technology, and in particular relate to a direct connection structure between the head end of a GIL and a cable in an underground pipe gallery and a pressure-resistant test method thereof, which are mainly used when the GIL and the cable are directly connected in an underground pipe gallery. The GIL on-site withstand voltage test can be realized without dismantling the cable terminal.

Background technique

At present, the common connection methods between GIL and cable include indirect connection of bushing terminal and direct connection of cable terminal.

Among them, the indirect connection method of the bushing terminal is mainly used in outdoor scenes because the bushing needs to be placed outdoors before connecting the lead wires, and the outdoor environment is also convenient for on-site withstand voltage tests. However, an outdoor terminal platform needs to be built and a certain area is required. If this connection method is arranged in the urban area, the cost is high and it is not conducive to the urban landscape and environmental safety; the direct connection method of the cable terminal is applicable to both indoor and outdoor scenes, but GIL in the underground pipe gallery appears in engineering applications. When both the head and the end are directly connected to the cable, this is the first application. In the case of fully considering the feasibility of the GIL and cable connection layout space, the space requirements for the GIL on-site withstand voltage test must also be considered.

1. In engineering application, the head end of the GIL is directly connected with the cable in the underground pipe corridor.

When both the head and the end of the GIL are directly connected to the cable, the vertical and lateral arrangement of the three-dimensional space of the compact pipe gallery is adopted to meet the space size for personnel construction, maintenance, and testing. The branch outlets of the GIL are directly connected to the cables through the cable terminals. The type of installation platform is installed at a high position. After the installation is completed, the installation platform is moved out of the feeding port, and the electrical connection is finally completed.

2. The current situation of the GIL on-site voltage withstand scheme when both the head and the end of the GIL are directly connected to the cables in the underground pipe gallery.

For the GIL on-site withstand voltage test, because the GIL and the cable implement different withstand voltage standards, the cable cannot be subjected to the insulation withstand voltage test according to the GIL standard, so the GIL line needs to be separately subjected to the on-site insulation withstand voltage test.

Explanation 1: GIL is divided into two types: three-phase split-box GIL and three-phase shared-box GIL. Among them, the structure of each phase of the three-phase split-box GIL is independent, and the withstand voltage test is also independent and unrelated to each phase; the three-phase shared box GIL Because the three phases are co-located in the same box, there is an electrical insulation correlation between the phases. Only after all three phases have passed the insulation withstand voltage test can the GIL insulation withstand voltage test be considered qualified.

Explanation 2: Elaborate on the technical scheme of withstand voltage when the three-phase common box GIL and the cable are directly connected under complex working conditions.

When the head and end of the GIL are directly connected to the cable in the underground pipe gallery, it is necessary to ensure that the GIL is electrically disconnected from the cable terminal and the cable part when the GIL is withstand voltage on site:

1) When the GIL is installed for the first time, it cannot be directly connected to the cable first. It is necessary to wait for the GIL to complete the on-site withstand voltage test before implementing the direct connection between the GIL and the cable part; where one end of the GIL is used as the pressurized side, it is necessary not to connect the cable terminal first. , and then add insulation test tooling conductors that are connected to the main circuit of the GIL end in the terminal housing and cover the GIL end air chamber to finally realize the GIL field insulation test. The other end of the GIL is used as the non-pressurized side, so the cable side can not be connected first The cable terminal or the cable terminal on the cable side shall be connected first, but the detachable conductor for electrical connection in the terminal housing shall not be installed, and the main circuit at the end of the GIL shall be connected to the shielding ball at the end to realize electrical disconnection. After the GIL on-site insulation test is passed phase by phase, the electrical connection of the cable terminals at the beginning and end of the GIL is carried out.

2) If the insulation withstand voltage test after emergency repair is carried out when the GIL fails during operation, any end of the GIL head and end must be selected as the pressurized side. When any phase of the GIL on the pressurized side is connected to the insulation test tool, the first The originally connected cables and cable terminals of the phase are disassembled and pulled out from the end of the GIL, and then the conductors for the GIL withstand voltage test are connected and the gas chamber at the end of the GIL is sealed to realize the independence of the GIL on-site insulation and withstand voltage test for this phase; The remaining two phases of the GIL on the pressurized side are electrically disconnected. Considering that each phase needs a withstand voltage test, you can choose to disassemble the cable terminal in advance to achieve electrical disconnection or temporarily do not disassemble the cable terminal, only need to disassemble the inside of the terminal housing. The detachable conductor is used for electrical connection, and the main circuit at the end of the GIL is equipped with a shielding ball at the end to realize electrical disconnection; the GIL on the non-pressurized side does not need to disassemble the cable terminal, only the electrical connection in the terminal shell of each phase needs to be disassembled. Remove the conductor, and install the upper end shielding ball in the main circuit of each phase end of the GIL to realize electrical disconnection; after the phase-by-phase withstand voltage of the GIL is completed, the cable terminal and the cable need to be connected again.

When both the head and the end of the GIL are directly connected to the cable in the underground pipe gallery, because the existing technical scheme does not directly reserve the docking port for the withstand voltage test, and the insulation withstand voltage test of each phase of the GIL requires a corresponding test docking port, it needs to be disassembled repeatedly , Install the cable and the cable terminal to obtain the docking port of the GIL phase withstand voltage test:

1) After the GIL is installed for the first time, because the insulation and withstand voltage test of each phase of the GIL needs to reserve a test docking port, the GIL withstand voltage test docking port cannot be directly connected to the cable and the cable terminal. The electrical connection with the cable and cable terminal needs to be disconnected. If the cable and cable terminal have been installed, the detachable conductor for electrical connection in the terminal housing still needs to be dismantled. Open; the connection between the GIL and the cable and the cable terminal can only be implemented after all phases of the GIL have completed the on-site withstand voltage test.

2) If a failure occurs during GIL operation, if the insulation withstand voltage test after emergency repair is carried out, the electrical connection between the first end of the GIL and the cable terminal needs to be disconnected, and the cable and cable terminal that have been connected at either end of the GIL first and end are removed from the GIL. Disassemble and pull out the end, and then connect the tooling conductors for the GIL withstand voltage test, etc., to realize the independence of the GIL on-site insulation and withstand voltage test. The connection between the GIL and the cable and the cable terminal can only be implemented after all phases of the GIL have completed the on-site withstand voltage test. .

It can be seen that this will bring laborious and laborious procedures such as dismantling and reinstalling the cable side in the underground pipe gallery with limited space, and will also increase the failure of the airtight connection and the reduction of the insulation capacity during the second docking after the dismantling of the cable side A series of uncontrollable security risk factors.

Contents of the invention

The purpose of the embodiment of the present application is to provide a direct connection structure between the head end of the GIL and the cable in the underground pipe gallery and its withstand voltage test method. The GIL and the cable are installed in place at one time, and the terminal shell is removed without disassembling the cable terminal. The detachable conductor at the end of the GIL main circuit in the body forms an electrical isolation fracture. At the same time, it connects to the GIL withstand voltage equipment through the test interface reserved by the transition tee unit between the GIL and the cable terminal, and finally realizes the GIL on-site withstand voltage test, effectively reducing The GIL interleaves the waiting period with the installation process of the cable, thereby solving the problems in the background art.

In order to solve the above technical problems, the technical scheme of the direct connection structure between the head end of the GIL and the cable in the underground pipe gallery and the pressure test method provided by the embodiment of the present application is as follows:

In the first aspect, the embodiment of the present application discloses a direct connection structure between the head end of the GIL and the cable in the underground pipe gallery, including the underground pipe gallery, the first feeding port, the second feeding port, a conductive component, a tee unit and a GIL three-way Phase-splitting unit, the conductive component, tee unit and GIL three-phase phase-splitting unit are arranged in the underground pipe gallery, the first feeding port and the second feeding port are arranged on the underground pipe gallery, and the The conductive component is connected to the three-way unit, and the three-way unit is connected to the GIL three-phase phase-splitting unit.

In a preferred embodiment of any of the solutions above, the conductive component includes a cable, a cable terminal and a terminal housing, the cable is connected to the cable terminal, and the cable terminal is connected to the terminal housing.

In a preferred embodiment of any of the solutions above, the conductive component further includes a cable support, the cable support is connected to the cable, and the cable support is arranged on the installation platform.

In a preferred embodiment of any of the above schemes, the head end of the GIL is directly connected to the cable in the underground pipe gallery, and also includes an inspection cover plate and a cable terminal inspection port, and the cable terminal inspection port is arranged at the terminal on the casing, and the inspection cover is set on the inspection port of the cable terminal.

In a preferred embodiment of any of the above schemes, the tee unit is connected to the GIL withstand voltage test interface, the GIL withstand voltage test interface is provided with a test interface cover, and the GIL pressure test tooling is connected to the test interface. Interface cover connection.

In a preferred embodiment of any of the above schemes, the head end of the GIL is directly connected to the cable in the underground pipe gallery, and also includes a GIL pressure-resistant joint, and the GIL pressure-resistant joint communicates with the tee unit , the GIL pressure-resistant interface is provided with a pressure-resistant cover plate.

In a preferred embodiment of any of the above schemes, the direct connection structure between the head end of the GIL and the cable in the underground pipe gallery further includes a shielding ball, and the shielding ball is arranged in the terminal housing.

In a preferred embodiment of any of the solutions above, the conductive components are provided in multiple groups, and each group is connected.

In a preferred embodiment of any of the above solutions, there are multiple cable supports.

Compared with the existing technology, the head end of the GIL and the cable in the embodiment of the present application are directly connected in the underground pipe gallery, and the GIL and the cable are installed in place at one time, and the main circuit of the GIL in the terminal housing is removed without dismantling the cable terminal The conductor can be detachable at the end to form an electrical isolation fracture, and at the same time connect the GIL withstand voltage equipment through the test interface reserved by the transition tee unit between the GIL and the cable terminal, and finally realize the on-site withstand voltage test of the GIL, effectively reducing the gap between the GIL and the cable The installation process crosses the waiting period.

In the second aspect, a pressure test method for a direct connection structure between the head end of the GIL and the cable in the underground pipe gallery, the method includes the following steps:

Step 1: Open the inspection cover at the first feeding port and the second feeding port, pass through the cable terminal inspection port, remove the disassembled conductor inside the terminal shell, and install it on the main circuit at the end of each phase of the GIL, that is, the conductor at the end of the GIL side end The shielding ball forms an electrical break;

Step 2: Open the GIL pressure-resistant cover reserved on the side of the tee unit at either end of the GIL as the pressurized side, and install the conductor of the insulation test tool through the GIL pressure-resistant interface;

Step 3: Then introduce the GIL insulation withstand voltage test tool from the ground into the underground pipe gallery, connect it to the GIL withstand voltage interface, and realize the electrical connection with the GIL. After the inflation is completed, perform the GIL phase-by-phase insulation withstand voltage test operation;

Step 4: Set the numbers of the phases at the beginning and end of the GIL as Phase A1/Phase A2, Phase B1/Phase B2, Phase C1/Phase C2, and then the end side of Phase A2 is electrically connected to the GIL insulation withstand voltage test tooling, Phase A1, Phase B1 /B2, phase C1/C2 ends only need to disassemble the cable in the terminal housing, install the shielding ball, and form an electrical fracture, and then implement the main circuit insulation withstand voltage test from the GIL phase A2 end to the phase A1 end.

Compared with the existing technology, the pressure test method of the direct connection structure between the head end of the GIL and the cable in the underground pipe corridor in the embodiment of the present application, the GIL and the cable are installed in place at one time, and the terminal is removed without dismantling the cable terminal The detachable conductor at the end of the GIL main circuit in the shell forms an electrical isolation fracture, and at the same time connects the GIL withstand voltage equipment through the test interface reserved by the transition tee unit between the GIL and the cable terminal, and finally realizes the on-site withstand voltage test of GIL, which is effective Reduce the cross-waiting period of GIL and cable installation process.

When the GIL fails, there is no need to disassemble the cable terminal. Repeat the operation of the above step 1 to realize the separate on-site pressure test after the GIL repair, which perfectly avoids the trouble of dismantling and reinstalling the cable side in the underground pipe gallery with limited space. A series of uncontrollable safety factors such as laborious and cumbersome procedures, airtight connection failure and reduced insulation capacity during the second connection of the cable side improve the quality of the installation and test process.

Description of drawings

The drawings described here are used to provide a further understanding of the application and constitute a component of the application. The schematic embodiments and descriptions of the application are used to explain the application and do not constitute an improper limitation to the application. Hereinafter, some specific embodiments of the present application will be described in detail with reference to the accompanying drawings in an exemplary rather than restrictive manner. The same reference numerals in the drawings indicate the same or similar components or components. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the drawings:

Fig. 1 is a schematic diagram of the direct connection structure between the head end of the GIL and the cable in the underground pipe corridor according to the embodiment of the present application.

Fig. 2 is a top view in the M direction of Fig. 1 of the direct connection structure between the head end of the GIL and the cable in the underground pipe corridor according to the embodiment of the present application.

Fig. 3 is a schematic diagram of the pressure resistance of the direct connection structure between the head end of the GIL and the cable in the underground pipe gallery according to the embodiment of the present application.

Fig. 4 is a top view of the P direction in Fig. 3 of the direct connection structure between the head end of the GIL and the cable in the underground pipe corridor according to the embodiment of the present application.

Fig. 5 is a schematic diagram of the connection between the head end of the GIL and the cable in the underground pipe gallery, and any phase on the pressurized side of the GIL is connected to the insulation test tool.

Fig. 6 is a schematic diagram of the direct connection structure between the head end of the GIL and the cable in the underground pipe gallery of the embodiment of the present application. The GIL is electrically disconnected from the cable and the cable terminal without dismantling the cable terminal.

Fig. 7 is a schematic diagram of the structure of the GIL pressure-resistant interface reserved for the tee unit of the direct connection structure between the head end of the GIL and the cable in the underground pipe corridor according to the embodiment of the present application.

Fig. 8 is a side view of Fig. 7 in the direct connection structure between the head end of the GIL and the cable in the underground pipe corridor according to the embodiment of the present application.

Fig. 9 is a schematic structural diagram of the non-disconnected state of electrical connection between the GIL and the cable terminal in the direct connection structure between the head end of the GIL and the cable in the underground pipe corridor according to the embodiment of the present application.

Labels in the figure: underground pipe gallery 1, first feeding port 11, second feeding port 12, cable 2, cable support 21, cable terminal 3, terminal housing 31, inspection cover 32, cable terminal inspection port 33, GIL resistant Pressure test interface 34, test interface cover 35, tee unit 4, GIL three-phase phase-splitting unit 5, GIL pressure-resistant interface 6, installation platform 7, shielding ball 8, detachable conductor 9.

detailed description

In order to enable those skilled in the art to better understand the solutions of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Apparently, the described embodiment is only an embodiment of a component of the present application, rather than an embodiment of the entire component. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the scope of protection of this application.

It should be noted that when an element is referred to as being “fixed” or “disposed on” another element, it may be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

In the description of the present application, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", The orientation or positional relationship indicated by "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than Nothing indicating or implying that a referenced device or element must have a particular orientation, be constructed, and operate in a particular orientation should therefore not be construed as limiting the invention.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the present application, "plurality" means two or more, unless otherwise specifically defined.

The following embodiments of this application take the direct connection structure between the head end of the GIL and the cable in the underground pipe gallery and its pressure test method to have front wheels and rear wheels as an example to illustrate the scheme of this application in detail, but this embodiment does not limit this application. Apply for protection.

In this application, the terms are explained: GIL: a rigid gas-insulated transmission line enclosed by a rigid metal shell, filled with insulating gas, with a central conductive rod and epoxy support. Cable Termination: A device installed at the end of a cable that ensures electrical connection to the rest of the system and maintains insulation up to the point of connection.

Example

As shown in Figures 1 to 3, the embodiment of the present application provides a direct connection structure between the head end of the GIL and the cable in the underground pipe corridor. The direct connection structure in the pipe gallery, including the underground pipe gallery 1, the first feeding port 11, the second feeding port 12, the conductive component, the three-way unit 4 and the GIL three-phase phase-splitting unit 5, the conductive component, the three-way unit 4 and the GIL three-phase phase-splitting unit 5 are arranged in the underground pipe gallery 1, the first feeding port 11 and the second feeding port 12 are arranged on the underground pipe gallery 1, and the conductive component and the tee unit 4 Connection, the tee unit 4 is connected with the GIL three-phase phase splitting unit 5.

As shown in Figures 1 to 4, the conductive assembly includes a cable 2, a cable terminal 3 and a terminal housing 31, the cable 2 is connected to the cable terminal 3, and the cable terminal 3 is connected to the terminal housing 31 connected, the conductive component also includes a cable support 21, the cable support 21 is connected to the cable 2, the cable support 21 is arranged on the installation platform 7, the conductive component is provided in multiple groups, and each group There are multiple connections between the cable supports 21 .

As shown in Figures 1 to 4, the head end of the GIL is directly connected to the cable in the underground pipe gallery, and also includes an inspection cover 32 and a cable terminal inspection port 33, and the cable terminal inspection port 33 is set on the On the terminal housing 31, and the inspection cover 32 is covered on the cable terminal inspection port 33, the tee unit 4 communicates with the GIL withstand voltage test interface 34, and the GIL withstand voltage test interface 34 A test docking port cover 35 is arranged on it, and the GIL pressure-resistant test tooling is connected to the test docking port cover 35, and also includes a GIL pressure-resistant docking port 6, and the GIL pressure-resistant docking port 6 communicates with the tee unit 4, The GIL pressure-resistant interface 6 is provided with a pressure-resistant cover plate, and also includes a shielding ball 8 , and the shielding ball 8 is arranged in the terminal housing 31 .

Compared with the existing technology, the head end of the GIL and the cable in the embodiment of the present application are directly connected in the underground pipe gallery, and the GIL and the cable are installed in place at one time, and the main circuit of the GIL in the terminal housing is removed without dismantling the cable terminal The conductor can be detachable at the end to form an electrical isolation fracture, and at the same time connect the GIL withstand voltage equipment through the test interface reserved by the transition tee unit between the GIL and the cable terminal, and finally realize the on-site withstand voltage test of the GIL, effectively reducing the gap between the GIL and the cable The installation process crosses the waiting period.

In order to realize the on-site pressure test of the GIL without dismantling the cable terminal when the head end of the GIL is directly connected to the cable in the underground pipe gallery, the technical solution of the present invention is now described in detail.

In the engineering application of the present invention, the head end of the GIL is directly connected to the cable in the underground pipe gallery.

When both the head and the end of the GIL are directly connected to the cable 2, the vertical and lateral arrangement of the three-dimensional space of the compact pipe gallery is adopted to meet the space size for personnel construction, maintenance, and testing. The branch outlets of the GIL are respectively connected to the tee unit 4 (with insulation voltage test docking interface), and then directly connected with the cable 2 and the cable terminal 3. During installation, the installation is carried out at a high position through the mobile installation platform 7. After the installation is completed, the installation platform 7 moves out of the first feeding port 11 or the second feeding port 12. The electrical connection is finally completed, as shown in Figures 1 to 4, the GIL on-site pressure-resistant technical solution of the present invention when both the head and the end of the GIL are directly connected to the cable in the underground pipe gallery.

When the GIL is pressure-resistant after the first installation of the GIL, the detachable conductor 9 in the terminal housing 31 at the first end of the GIL is removed first, and then the shielding ball 8 is installed to form an electrical fracture, and the GIL insulation withstand voltage test tool is introduced from the ground into the ground Inside the pipe gallery 1, the electrical connection with the GIL is realized through the GIL pressure-resistant interface 6 reserved on the side of the tee unit 4 at either end of the GIL as the pressurized side. After the inflation is completed, the GIL is insulated phase by phase. Test operation, in the technical scheme of the present invention, mainly carry out technical scheme elaboration for GIL independent withstand voltage test, then set for the withstand voltage test of cable to pressurize from the far-end connection terminal of cable (non-GIL first end).

When a failure occurs during GIL operation, if the insulation withstand voltage test after emergency repair is carried out, the detachable conductor 9 in the terminal housing 31 at the first end of the GIL is removed first, and then the shielding ball 8 is installed to form an electrical fracture, and then the GIL insulation withstand voltage The test tooling is introduced from the ground into the underground pipe gallery, and the electrical connection with the GIL is realized through the GIL pressure-resistant interface reserved on the side of the tee unit at any end of the GIL as the pressurized side. After the inflation is completed, the GIL is carried out phase by phase. The insulation withstand voltage test operation, the operation process is the same as the insulation withstand voltage mode of the first installation, and there is no need to remove the cable terminal 3, the operation is safe and convenient, and the repair time can be greatly saved.

After all phases of the GIL have completed the on-site withstand voltage test, install the detachable conductor 9 between the end conductor of the GIL main circuit and the cable terminal, and restore the electrical connection between the GIL and the cable and the cable terminal (as shown in Figure 9).

Therefore, in the embodiment of the present invention, when the GIL and the cable are directly connected in the underground pipe gallery 1, the GIL and the cable 2 are installed in place at one time, and the tee unit 4 is added without disassembling the cable terminal 3 (reserving the insulation GIL withstand voltage test interface) to obtain the insulation GIL withstand voltage test interface 34, and save the cumbersome process of obtaining the insulation GIL withstand voltage test interface 34 by disassembling the cable terminal 3, avoiding the trouble caused by repeatedly disassembling the cable terminal of the cable machine Unsafe factors, and finally realize the separate on-site withstand voltage test of GIL, and do not need to disassemble the cable terminal to realize the separate on-site withstand voltage test after GIL emergency repair.

The second aspect, as shown in Figures 5 to 9, is a pressure test method for the direct connection structure between the head end of the GIL and the cable in the underground pipe gallery. When the head end of the GIL is directly connected to the cable, the branch outlets of each phase of the GIL are respectively Connect with the tee unit 4 (with a butt joint for the insulation withstand voltage test), and then directly connect with the cable 2 and the cable terminal 3; during the GIL insulation withstand voltage test, remove the terminal housing 31 without disassembling the cable terminal 3 The detachable conductor 9 at the end of the GIL main circuit forms an electrical isolation fracture. At the same time, the GIL withstand voltage test interface 34 reserved by the transition tee unit between the GIL and the cable terminal 3 is used to connect to the GIL withstand voltage equipment, and finally realize the separate site of GIL Withstand voltage test, and during the withstand voltage operation process, it can effectively reduce the cross waiting period of GIL and cable installation process.

As shown in Figures 5 to 9, a pressure test method for the direct connection structure between the head end of the GIL and the cable in the underground pipe gallery, the method includes the following steps:

Step 1: Open the inspection cover 32 at the first feeding port and the second first feeding port, pass through the cable terminal inspection port 33, first remove the detachable conductor 9 in the terminal housing 31 at the first end of the GIL, and then install The shielding ball 8 forms an electrical fracture;

Step 2: Open the GIL pressure-resistant cover plate reserved on the side of the tee unit 4 at either end of the GIL as the pressurized side, and install the conductor of the insulation test tool through the GIL pressure-resistant interface 6;

Step 3: Then introduce the GIL insulation withstand voltage test tooling from the ground into the underground pipe gallery 1, connect it to the GIL withstand voltage interface 6, and realize the electrical connection with the GIL. After the inflation is completed, conduct the GIL phase-by-phase insulation withstand voltage test operate;

Step 4: Set the numbers of the phases at the beginning and end of the GIL as Phase A1/Phase A2, Phase B1/Phase B2, Phase C1/Phase C2, and then the end side of Phase A2 is electrically connected to the GIL insulation withstand voltage test tooling, Phase A1, Phase B1 /B2, phase C1/C2 ends only need to disassemble the cable 2 in the terminal housing 31, install the shielding ball 8, and then form an electrical fracture, and then implement the main circuit insulation withstand voltage test from the GIL phase A2 end to the phase A1 end .

So on and so forth:

After the end side of phase B2 is electrically connected to the GIL insulation withstand voltage test tooling, the end sides of phase B1, phase A1/phase A2, and phase C1/phase C2 only need to dismantle the detachable conductor 9 in the terminal housing and install the shielding ball 8. The electrical fracture can be formed, and then the main circuit insulation withstand voltage test from the GIL phase B2 end to the phase B1 end is implemented.

After the end side of phase C2 is electrically connected to the GIL insulation withstand voltage test tool, the end sides of phase C1, phase B1/phase B2, phase A1/phase A2 only need to disassemble the detachable conductor 9 in the terminal housing 31, and install the shielding ball 8. The electrical fracture can be formed, and then the main circuit insulation withstand voltage test from the GIL phase C2 terminal to the phase C1 terminal is implemented.

After the on-site withstand voltage test is completed for each phase of the GIL, install the detachable conductor 9 between the terminal conductor of the GIL main circuit and the cable terminal 3, and restore the electrical connection between the GIL and the cable 2 and the cable terminal 3.

When a failure occurs during GIL operation, if the insulation withstand voltage test is carried out after emergency repair, there is no need to disassemble the cable terminal 3. Repeat the operation of the above step 1 to realize another separate on-site withstand voltage test after the emergency repair of the GIL. The operation process is the same as the first installation The insulation and withstand voltage mode is the same as when the cable terminal is not removed. The operation is safe and convenient, which can greatly save the repair time, effectively reduce the cumbersome procedures for realization, and improve the quality of the installation and test process.

Compared with the existing technology, the pressure test method of the direct connection structure between the head end of the GIL and the cable in the underground pipe corridor in the embodiment of the present application, the GIL and the cable are installed in place at one time, and the terminal is removed without dismantling the cable terminal The detachable conductor at the end of the GIL main circuit in the shell forms an electrical isolation fracture, and at the same time connects the GIL withstand voltage equipment through the test interface reserved by the transition tee unit between the GIL and the cable terminal, and finally realizes the on-site withstand voltage test of GIL, which is effective Reduce the cross-waiting period of GIL and cable installation process.

When the GIL fails, there is no need to disassemble the cable terminal. Repeat the operation of the above step 1 to realize the separate on-site pressure test after the GIL repair, which perfectly avoids the trouble of dismantling and reinstalling the cable side in the underground pipe gallery with limited space. A series of uncontrollable safety factors such as laborious and cumbersome procedures, airtight connection failure and reduced insulation capacity during the second connection of the cable side improve the quality of the installation and test process.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit it; although the application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for the technical features of the components or all components; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technology of each embodiment of the application. scope of the program.

Claims (10)

1. A direct connection structure of a head end and a tail end of a GIL (general information language) in a underground pipe gallery is characterized by comprising the underground pipe gallery, a first feeding port, a second feeding port, a conductive component, a three-way unit and a GIL three-phase splitting unit, conductive component, tee bend unit and GIL three-phase splitting unit set up in the underground pipe gallery, first dog-house and second dog-house set up in on the underground pipe gallery, conductive component and tee bend unit connection, tee bend unit and GIL three-phase splitting unit connection.

2. The GIL head and tail end and cable direct connection structure in a underground pipe gallery according to claim 1, wherein the conductive assembly comprises a cable, a cable terminal and a terminal housing, the cable is connected with the cable terminal, and the cable terminal is connected with the terminal housing.

3. The GIL head and tail end and cable direct connection structure in a subterranean pipe gallery according to claim 1, wherein the conductive assembly further comprises a cable support, the cable support is connected with the cable, and the cable support is arranged on the mounting platform.

4. The GIL head end and tail end and cable direct connection structure in an underground pipe gallery according to claim 3, further comprising an access cover plate and a cable terminal access opening, wherein the cable terminal access opening is formed in the terminal shell, and the access cover plate is covered on the cable terminal access opening.

5. The GIL head and tail end and cable direct connection structure in a underground pipe gallery according to claim 4, wherein the three-way unit is communicated with a GIL pressure test butt joint, a test butt joint cover plate is arranged on the GIL pressure test butt joint, and a GIL pressure test tool is connected with the test butt joint cover plate.

6. The GIL head end and tail end and cable direct connection structure in a underground pipe gallery according to claim 5, further comprising a GIL pressure-resistant butt joint, wherein the GIL pressure-resistant butt joint is communicated with the three-way unit, and a pressure-resistant cover plate is arranged on the GIL pressure-resistant butt joint.

7. The GIL head and tail end and cable direct connection structure in an underground pipe gallery according to claim 6, further comprising a shielding ball disposed in the terminal housing.

8. The GIL end-to-end and cable direct connection structure in a subterranean pipe gallery as claimed in claim 7, wherein said conductive assembly is provided in a plurality of sets and connected between each two sets.

9. The GIL head and tail end and cable direct connection structure in a underground pipe gallery according to claim 8, wherein the cable support is provided in plurality.

10. A method for testing the pressure resistance of the tip and tail of the GIL and the direct connection of cables to the underground pipe gallery as claimed in claim 9, wherein the method comprises the steps of:

opening access cover plates at a first feeding port and a second feeding port, penetrating through a cable terminal access port, removing detachable conductors in the terminal shell, and installing shielding balls on end main loops of phases of the GIL, namely end conductors of the side ends of the GIL to form an electrical fracture;

opening a GIL voltage-resistant cover plate reserved on the side face of the three-way unit at any end of the GIL serving as a pressurizing side, and installing an insulation test tool conductor through a GIL voltage-resistant butt joint;

introducing a GIL insulation and voltage resistance test tool into the underground pipe gallery from the ground, connecting the GIL insulation and voltage resistance test tool to the GIL voltage resistance butt joint to realize electrical connection with the GIL, and performing GIL phase-by-phase insulation and voltage resistance test operation after the gas is filled;

and setting the serial numbers of all phases at the head end and the tail end of the GIL as a phase A1/phase A2, a phase B1/phase B2 and a phase C1/phase C2, electrically connecting the end side of the phase A2 with a GIL insulation voltage resistance test tool, only disassembling a cable in a terminal shell, installing a shielding ball to form an electrical fracture at the end sides of the phase A1, the phase B1/B2 and the phase C1/C2, and then performing a main loop insulation voltage resistance test from the end A2 of the GIL phase to the end A1 of the phase.

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