A GIL and busbar unit thereof

Abstract

This invention relates to the field of gas-insulated metal-enclosed equipment technology, and more particularly to a gas-insulated metal-enclosed (GIL) and its busbar unit. The GIL busbar unit includes a cylindrical body containing three-phase conductors and fixed three-post insulators and sliding three-post insulators for supporting the conductors. The fixed three-post insulators are fixedly connected to the three-phase conductors, and the sliding three-post insulators are fixedly connected to one phase conductor, while slidingly assembled with the other two phase conductors along the conductor's axial direction. When thermal expansion and contraction occur, the phase conductor fixedly connected to the sliding three-post insulator can drive the sliding three-post insulator to move axially along the cylindrical body. The other two phase conductors each have a free end, allowing for free thermal expansion and contraction without generating additional stress on the sliding three-post insulator. This avoids additional stress on the sliding three-post insulator due to asynchronous thermal expansion and contraction of the three phase conductors, ensuring the support stability of the sliding three-post insulator.

Description

Technical Field

[0001] This invention relates to the field of gas-insulated metal-enclosed equipment technology, and more particularly to a GIL and its busbar unit. Background Technology

[0002] GIL (Gas Insulator) is a power transmission device that uses a metal casing to enclose a conductive rod, with insulating gas filling the casing. The casing and conductive rod are arranged coaxially. It has advantages such as large transmission capacity, low unit loss, minimal environmental impact, high operational reliability, and space saving, and has been widely used in power transmission from hydropower stations and nuclear power plants. With the increasing scarcity of urban land and the advancement of underground utility tunnel construction, in order to achieve miniaturized GIL design, save equipment footprint, reduce manufacturing costs, and simultaneously improve the natural power transmission of the GIL busbar, three-phase common-enclosure compact GILs are gradually being developed and applied in complex and compact environments.

[0003] The existing three-phase common-enclosure GIL structure is typically as shown in the Chinese utility model patent with authorization announcement number CN215646134U, including a housing, three-phase conductors, and fixed three-post insulators and sliding three-post insulators for supporting the conductors. The fixed three-post insulators are fixedly connected to the inner wall of the housing through end connecting bars, and the sliding three-post insulators are slidably assembled inside the housing. Both the fixed and sliding three-post insulators are provided with three hollow cylindrical central inserts, through which the three-phase conductors pass and are fixedly connected.

[0004] The aforementioned patent, by simultaneously installing fixed and sliding three-post insulators within the casing, allows one end of the conductor to be free, accommodating free thermal expansion and contraction of the conductor and compensating for the effects of temperature field changes within the GIL caused by load and environmental variations during operation. However, in actual operation, the thermal expansion and contraction of the conductors within the casing are not synchronized. The resulting additional stress acts on the sliding three-post insulator, causing it to withstand a certain amount of torsional force. With long-term operation of the GIL, the support stability of the sliding three-post insulator cannot be guaranteed. Summary of the Invention

[0005] The purpose of this invention is to provide a busbar unit for a gas-insulated barrier (GIL) to solve the problem that the additional stress caused by the asynchronous thermal expansion and contraction of the three-phase conductors in existing GIL busbar units affects the support stability of the sliding three-post insulator. Furthermore, this invention aims to provide a GIL that also solves the problem that the additional stress caused by the asynchronous thermal expansion and contraction of the three-phase conductors in existing GILs affects the support stability of the sliding three-post insulator, thereby impacting the stable operation of the GIL.

[0006] To achieve the above objectives, the bus unit of the GIL of the present invention adopts the following technical solution:

[0007] A busbar unit of a GIL includes a cylinder, inside which are disposed three-phase conductors and fixed three-post insulators and sliding three-post insulators for supporting the three-phase conductors. The fixed three-post insulators are fixedly connected to the three-phase conductors, and the sliding three-post insulators are fixedly connected to one phase conductor of the three-phase conductors and are slidably assembled with the other two phase conductors in the axial direction of the conductors.

[0008] Beneficial Effects: The busbar unit of the GIL of this invention is an improvement on the existing GIL busbar unit. It fixes the three-post insulator to the three-phase conductors, and the sliding three-post insulator is fixedly connected to one phase conductor while slidingly assembled with the other two phase conductors. When the GIL is arranged vertically or inclined, because the sliding three-post insulator is fixedly connected to one phase conductor, that phase conductor can provide support for the sliding three-post insulator, preventing it from sliding downwards along the cylinder. This satisfies various working conditions such as vertical, inclined, and horizontal arrangement of the GIL. This design meets the application requirements of the system. Furthermore, since one phase of the three-phase conductor is fixedly connected to the sliding three-post insulator, while the other two phases are slidably assembled with it, the phase conductor fixedly connected to the sliding three-post insulator can drive the insulator to move axially along the cylinder when thermal expansion and contraction occur. The other two phase conductors each have a free end, allowing for free thermal expansion and contraction without generating additional stress on the sliding three-post insulator. This avoids the additional stress on the sliding three-post insulator caused by asynchronous thermal expansion and contraction of the three phase conductors, ensuring the support stability of the sliding three-post insulator.

[0009] Furthermore, one of the phase conductors is fixedly connected to the cylindrical insert on the sliding three-post insulator, and the other two phase conductors are slidably assembled with the cylindrical insert on the sliding three-post insulator.

[0010] Beneficial effects: The three-phase conductors are respectively inserted into the three cylindrical inserts on the sliding three-post insulator, which facilitates assembly and provides reliable support for the three-phase conductors.

[0011] Furthermore, each cylindrical insert is provided with a guide structure for guiding the conductor.

[0012] Beneficial effects: The conductor has a relatively long overall length. By setting guide structures in each cylindrical insert, the movement of the conductor in the cylindrical insert can be guided, preventing the conductor from tilting and making the conductor support more stable and reliable. Moreover, the guide structure, cylindrical insert, and the annular gap formed by the conductor can constrain the metal particles generated during the conductor installation and operation, further ensuring the insulation performance of the busbar.

[0013] Furthermore, at least part of the guide structure is located near both ends of the cylindrical insert.

[0014] Beneficial effects: At least part of the guide structure is located near both ends of the cylindrical insert, which can better guide the conductor when it is inserted into the cylindrical insert, making conductor insertion easier.

[0015] Furthermore, a particle trap is provided on the inner side of the cylindrical insert on the axially outer side of the guide structure.

[0016] Beneficial effects: Conductive particles are easily generated when conductors enter and exit the cylindrical insert. By setting particle traps on the inner side of the cylindrical insert on the axial outer side of the guide structure, the conductive particles generated when the conductor enters and exits can be effectively captured, preventing the conductive particles from moving along the conductor surface and affecting the insulation performance of the busbar.

[0017] Furthermore, the particle trap is an annular groove formed on the inner side of the cylindrical insert.

[0018] Beneficial effects: By creating annular grooves on the inner side of the cylindrical insert to form a particle trap, the annular groove structure is simple, has a large capacity, and provides good particle confinement.

[0019] Furthermore, the conductor and its slidingly fitted cylindrical insert make conductive contact.

[0020] Beneficial effect: It enables the conductor and the cylindrical insert that slides with it to have the same potential, and prevents the conductor from discharging into the cylindrical insert and affecting the insulation performance of the busbar.

[0021] Furthermore, the guide structure protrudes from the inner side of the cylindrical insert, and the conductor and the cylindrical insert are electrically connected through an annular contact.

[0022] Beneficial effects: The guide structure protrudes from the inner side of the cylindrical insert, and the ring-shaped contact finger ensures a reliable electrical connection between the conductor and the cylindrical insert.

[0023] Furthermore, the guide structure is a guide ring installed on the inner side of the cylindrical insert.

[0024] Beneficial effects: Setting a guide ring as a guide structure is simple. After long-term use, the guide ring wears down with the conductor, and it is easy to replace when the wear is severe.

[0025] The technical solution adopted by the present invention GIL is as follows:

[0026] GIL includes at least two busbar units connected in sequence. Each busbar unit includes a cylinder containing three-phase conductors and fixed three-post insulators and sliding three-post insulators for supporting the three-phase conductors. The fixed three-post insulators are fixedly connected to the three-phase conductors, and the sliding three-post insulators are fixedly connected to one phase conductor of the three-phase conductors and are slidably assembled with the other two phase conductors in the axial direction of the conductors. The three-phase conductors of adjacent busbar units are electrically connected accordingly.

[0027] Beneficial Effects: This invention improves upon existing GILs by fixing the three-post insulators of each busbar unit to the three-phase conductors, and fixing the sliding three-post insulators to one phase conductor while sliding them to the other two phase conductors. When the GIL is arranged vertically or inclined, the fixed connection between the sliding three-post insulators and one phase conductor provides support, preventing the insulators from sliding downwards along the cylinder. This satisfies the application requirements of various working conditions, including vertical, inclined, and horizontal GIL arrangements. In this configuration, one phase of the three-phase conductor is fixedly connected to the sliding three-post insulator, while the other two phases are slidably assembled with the sliding three-post insulator. Thus, when the conductor fixedly connected to the sliding three-post insulator undergoes thermal expansion and contraction, it can drive the sliding three-post insulator to move axially along the cylinder. The other two phase conductors each have one free end, allowing them to expand and contract freely without generating additional stress on the sliding three-post insulator. This avoids the additional stress on the sliding three-post insulator caused by asynchronous thermal expansion and contraction of the three-phase conductors, ensuring the support stability of the sliding three-post insulator and thus ensuring the stable operation of the GIL.

[0028] Furthermore, one of the phase conductors is fixedly connected to the cylindrical insert on the sliding three-post insulator, and the other two phase conductors are slidably assembled with the cylindrical insert on the sliding three-post insulator.

[0029] Beneficial effects: The three-phase conductors are respectively inserted into the three cylindrical inserts on the sliding three-post insulator, which facilitates assembly and provides reliable support for the three-phase conductors.

[0030] Furthermore, each cylindrical insert is provided with a guide structure for guiding the conductor.

[0031] Beneficial effects: The conductor has a relatively long overall length. By setting guide structures in each cylindrical insert, the movement of the conductor in the cylindrical insert can be guided, preventing the conductor from tilting and making the conductor support more stable and reliable. Moreover, the guide structure, cylindrical insert, and the annular gap formed by the conductor can constrain the metal particles generated during the conductor installation and operation, further ensuring the insulation performance of the busbar.

[0032] Furthermore, at least part of the guide structure is located near both ends of the cylindrical insert.

[0033] Beneficial effects: At least part of the guide structure is located near both ends of the cylindrical insert, which can better guide the conductor when it is inserted into the cylindrical insert, making conductor insertion easier.

[0034] Furthermore, a particle trap is provided on the inner side of the cylindrical insert on the axially outer side of the guide structure.

[0035] Beneficial effects: Conductive particles are easily generated when conductors enter and exit the cylindrical insert. By setting particle traps on the inner side of the cylindrical insert on the axial outer side of the guide structure, the conductive particles generated when the conductor enters and exits can be effectively captured, preventing the conductive particles from moving along the conductor surface and affecting the insulation performance of the busbar.

[0036] Furthermore, the particle trap is an annular groove formed on the inner side of the cylindrical insert.

[0037] Beneficial effects: By creating annular grooves on the inner side of the cylindrical insert to form a particle trap, the annular groove structure is simple, has a large capacity, and provides good particle confinement.

[0038] Furthermore, the conductor and its slidingly fitted cylindrical insert make conductive contact.

[0039] Beneficial effect: It enables the conductor and the cylindrical insert that slides with it to have the same potential, and prevents the conductor from discharging into the cylindrical insert and affecting the insulation performance of the busbar.

[0040] Furthermore, the guide structure protrudes from the inner side of the cylindrical insert, and the conductor and the cylindrical insert are electrically connected through an annular contact.

[0041] Beneficial effects: The guide structure protrudes from the inner side of the cylindrical insert, and the ring-shaped contact finger ensures a reliable electrical connection between the conductor and the cylindrical insert.

[0042] Furthermore, the guide structure is a guide ring installed on the inner side of the cylindrical insert.

[0043] Beneficial effects: Setting a guide ring as a guide structure is simple. After long-term use, the guide ring wears down with the conductor, and it is easy to replace when the wear is severe. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the bus unit structure in Embodiment 1 of the GIL of the present invention;

[0045] Figure 2 A schematic diagram showing the fixed connection between the conductor and the cylindrical insert;

[0046] Figure 3 A schematic diagram of the sliding assembly of the conductor and the cylindrical insert;

[0047] In the diagram: 1. Fixed connecting plate; 2. Fixed three-post insulator; 3. Particle trap; 4. Cylinder; 5. Conductor; 6. Sliding three-post insulator; 7. Guide ring; 8. Weld hole; 9. Cylindrical insert; 10. Annular contact finger. Detailed Implementation

[0048] This invention, GIL, improves upon existing GILs by fixing the three-post insulator to the three-phase conductors, and fixing the sliding three-post insulator to one phase conductor of the three-phase conductors, while slidingly assembling it with the other two phase conductors. The phase conductor fixedly connected to the sliding three-post insulator provides support for the sliding three-post insulator, which can meet the application requirements of various working conditions such as vertical, inclined, and horizontal GILs. At the same time, it allows the three-phase conductors to expand and contract freely due to thermal changes without generating additional stress on the sliding three-post insulator, ensuring the support stability of the sliding three-post insulator, and thus ensuring the stable operation of the GIL.

[0049] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0050] Example 1 of the GIL of the present invention:

[0051] GIL consists of multiple bus units connected in sequence, such as Figure 1 As shown, the busbar unit includes a cylindrical body 4, inside which are three-phase conductors 5 and fixed three-post insulators 2 and sliding three-post insulators 6 for supporting the three-phase conductors 5. The three legs of the fixed three-post insulator 2 are fixedly connected to the cylindrical body 4 via a fixed connecting plate 1. The sliding three-post insulator 6 is axially slidably assembled inside the cylindrical body 4. Rollers are installed at the lower two legs of the sliding three-post insulator 6 to enable axial sliding, and grounding components are installed at the upper legs to ground the sliding three-post insulator 6. Particle traps 3 are installed inside the cylindrical body 4 at positions corresponding to the fixed three-post insulators 2 and sliding three-post insulators 6. The cylindrical bodies 4 of adjacent busbar units are fixedly connected via flanges, and the three-phase conductors 5 of adjacent busbar units are electrically connected accordingly.

[0052] The fixed three-post insulator 2 includes an insulating base, on which three cylindrical inserts 9 are spaced circumferentially. The three-phase conductors 5 are respectively fixedly inserted into the three cylindrical inserts 9. The three cylindrical inserts 9 have identical structures, such as... Figure 2As shown, each cylindrical insert 9 has a welding hole 8. The conductor 5 is inserted into the cylindrical insert 9 and fixedly connected to the cylindrical insert 9 by welding. On the inner surface of each cylindrical insert 9, near both ends, there are mounting grooves. Guide rings 7 are installed in the mounting grooves. The inner diameter of the guide rings 7 matches the outer diameter of the conductor 5. When the conductor 5 is inserted into the cylindrical insert 9, the guide rings 7 guide the conductor 5, making insertion easier. On the inner surface of each cylindrical insert 9, near both ends, there are also annular grooves. These grooves are located axially outside the corresponding guide rings 7. These grooves form a particle trap, which can capture conductive particles generated during the insertion of the conductor 5, preventing the conductive particles from moving along the conductor 5 and affecting the insulation performance of the busbar.

[0053] The sliding three-post insulator 6 includes an insulating base with three circumferentially spaced cylindrical inserts 9. Three-phase conductors 5 are respectively inserted into the three cylindrical inserts 9. One phase conductor 5 is fixedly connected to one cylindrical insert 9, while the other two phase conductors 5 are slidably assembled into the other two cylindrical inserts 9. The structure of the cylindrical insert 9 fixedly connected to one phase conductor 5 is the same as the structure of the three cylindrical inserts 9 of the fixed three-post insulator 2, and the conductor 5 is fixedly connected to the cylindrical insert 9 by welding. The structure of the two cylindrical inserts slidably assembled with the two phase conductors 5 is the same, such as... Figure 3 As shown, mounting grooves are provided on the inner surface of the cylindrical insert 9 near both ends. Guide rings 7 are installed in these grooves, with the inner diameter of the guide rings 7 matching the outer diameter of the conductor 5. This guide rings guide the conductor 5 during insertion and movement within the cylindrical insert 9, preventing tilting and providing more stable and reliable support. Furthermore, the annular gap formed by the guide structure, the cylindrical insert 9, and the conductor 5 confines metal particles generated during insertion and operation, further ensuring the insulation performance of the busbar. Annular grooves are also provided on the inner surface of each cylindrical insert 9 near both ends. These grooves are located axially outside the corresponding guide rings 7, forming a particle trap that captures conductive particles generated during conductor insertion, preventing them from moving along the conductor 5 and affecting the busbar's insulation performance. The guide ring 7 protrudes from the inner side of the cylindrical insert 9. An installation groove is provided on the inner side of the cylindrical insert 9, and an annular contact finger 10 is provided in the installation groove. The conductor 5 and the cylindrical insert 9 are electrically connected through the annular contact finger 10, so that the conductor 5 and the cylindrical insert 9 have the same potential, thus preventing the conductor 5 from discharging to the cylindrical insert 9 and affecting the insulation performance of the busbar.

[0054] When assembling the busbar unit, the three-phase conductor 5 is first assembled with the fixed three-post insulator 2 and the sliding three-post insulator 6. Then, the fixed three-post insulator 2 is fixedly connected to the cylinder 4. Finally, insulating gas at the rated pressure is filled into the cylinder 4 to achieve insulation.

[0055] The fixed three-post insulator 2 is fixedly connected to the three-phase conductor 5, and the sliding three-post insulator 6 is fixedly connected to one phase conductor 5 of the three-phase conductor 5, while being slidably assembled with the other two phase conductors 5. When the GIL is arranged vertically or inclined, since the sliding three-post insulator 6 is fixedly connected to one phase conductor 5 of the three-phase conductor 5, that phase conductor 5 can provide support for the sliding three-post insulator 6 and prevent the sliding three-post insulator 6 from sliding downward along the cylinder 4. When the GIL is arranged horizontally, the cylinder 4 provides support for the sliding three-post insulator 6, so that the sliding three-post insulator 6 can only slide along the cylinder 4 in the horizontal direction, thereby meeting the application requirements of various working conditions such as vertical, inclined, and horizontal arrangement of the GIL. Meanwhile, since one phase conductor 5 of the three-phase conductor 5 is fixedly connected to the sliding three-post insulator 6, and the other two phase conductors 5 are slidably assembled with the sliding three-post insulator 6, the phase conductor 5 fixedly connected to the sliding three-post insulator 6 can drive the sliding three-post insulator 6 to move axially along the cylinder 4 when thermal expansion and contraction occur. The other two phase conductors 5 each have one end as a free end, which can freely expand and contract without generating additional stress on the sliding three-post insulator 6. This can avoid the additional stress on the sliding three-post insulator 6 caused by the asynchronous thermal expansion and contraction of the three-phase conductors 5, ensure the support stability of the sliding three-post insulator 6, and thus ensure the stable operation of GIL.

[0056] In the above embodiment 1, one phase of the three-phase conductor is welded to a cylindrical insert of the sliding three-post insulator; while in other embodiments, the conductor and the cylindrical insert can also be fixed by crimping, wedging or screw connection.

[0057] In the above embodiment 1, the guide rings are located near both ends of the cylindrical insert; while in other embodiments, multiple guide rings can be provided, such that some guide rings are located near both ends of the cylindrical insert, and the remaining guide rings are located near the middle region of the cylindrical insert.

[0058] In the above embodiment 1, an annular groove is formed on the inner side of the cylindrical insert to create a particle trap; in other embodiments, several blind holes can also be formed on the inner side of the cylindrical insert to capture particles.

[0059] In Embodiment 1 above, the conductor and the cylindrical insert that slides with it are electrically connected through an annular contact; while in other embodiments, the conductor and the cylindrical insert that slides with it can also be electrically connected through a flexible connection.

[0060] In the above embodiment 1, a guide ring is installed on the inner side of the cylindrical insert to guide the conductor; in other embodiments, three arc-shaped guide pieces can also be installed circumferentially at intervals on the inner side of the cylindrical insert, the three arc-shaped guide pieces being concentric to guide the conductor.

[0061] The present invention also provides an embodiment of a bus unit for a GIL, the specific structure of which is the same as the structure of the bus unit in the above-described GIL embodiments, and will not be described again here.

[0062] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.

Claims

1. A busbar unit for a GIL, comprising a cylindrical body (4), wherein a three-phase conductor (5) is disposed within the cylindrical body (4), and a fixed three-post insulator (2) and a sliding three-post insulator (6) for supporting the three-phase conductor (5), characterized in that: The fixed three-post insulator (2) is fixedly connected to the three-phase conductor (5), and the sliding three-post insulator (6) is fixedly connected to one of the three-phase conductors (5), and is slidably assembled with the other two phase conductors (5) in the axial direction of the conductor (5). The one phase conductor (5) is fixedly connected to the cylindrical insert (9) on the sliding three-post insulator (6), and the other two phase conductors (5) are slidably assembled with the cylindrical insert (9) on the sliding three-post insulator (6).

2. The bus unit of GIL according to claim 1, characterized in that: Each cylindrical insert (9) is provided with a guide structure for guiding the conductor (5).

3. The bus unit of GIL according to claim 2, characterized in that: At least part of the guide structure is located near both ends of the cylindrical insert (9).

4. The bus unit of GIL according to claim 3, characterized in that: The inner side of the cylindrical insert (9) is provided with a particle trap on the axial outer side of the guide structure.

5. The bus unit of GIL according to claim 4, characterized in that: The particle trap is an annular groove formed on the inner side of the cylindrical insert (9).

6. The bus unit of GIL according to any one of claims 2-5, characterized in that: The conductor (5) and the tubular insert (9) that slides with it are in conductive contact.

7. The bus unit of GIL according to claim 6, characterized in that: The guide structure protrudes from the inner side of the cylindrical insert (9), and the conductor (5) and the cylindrical insert (9) are electrically connected through the annular contact finger (10).

8. The bus unit of GIL according to claim 7, characterized in that: The guiding structure is a guide ring (7) installed on the inner side of the cylindrical insert (9).

9. A GIL, comprising at least two busbar units connected in sequence, characterized in that: The busbar unit includes a cylinder (4), inside which are provided three-phase conductors (5) and fixed three-post insulators (2) and sliding three-post insulators (6) for supporting the three-phase conductors (5). The fixed three-post insulators (2) are fixedly connected to the three-phase conductors (5), and the sliding three-post insulators (6) are fixedly connected to one of the three-phase conductors (5) and are slidably assembled with the other two phase conductors (5) in the axial direction of the conductors (5). The one phase conductor (5) is fixedly connected to the cylindrical insert (9) on the sliding three-post insulator (6), and the other two phase conductors (5) are slidably assembled with the cylindrical insert (9) on the sliding three-post insulator (6). The three-phase conductors (5) of adjacent busbar units are electrically connected accordingly.

10. The GIL according to claim 9, characterized in that: Each cylindrical insert (9) is provided with a guide structure for guiding the conductor (5).

11. The GIL according to claim 10, characterized in that: At least part of the guide structure is located near both ends of the cylindrical insert (9).

12. The GIL according to claim 11, characterized in that: The inner side of the cylindrical insert (9) is provided with a particle trap on the axial outer side of the guide structure.

13. The GIL according to claim 12, characterized in that: The particle trap is an annular groove formed on the inner side of the cylindrical insert (9).

14. The GIL according to any one of claims 10-13, characterized in that: The conductor (5) and the tubular insert (9) that slides with it are in conductive contact.

15. The GIL according to claim 14, characterized in that: The guide structure protrudes from the inner side of the cylindrical insert (9), and the conductor (5) and the cylindrical insert (9) are electrically connected through the annular contact finger (10).

16. The GIL according to claim 15, characterized in that: The guiding structure is a guide ring (7) installed on the inner side of the cylindrical insert (9).

Images