Spacer for gas insulated switchgear

Abstract

The present invention relates to a spacer (20) for a gas insulated switchgear. In the spacer (20), a spacer body (22) made of an insulating material forms a skeleton. A seating groove (24) surrounding the edge of the spacer body (22) is formed. A seal (30) is seated in the seating groove (24). At least one gas connection path (26) is formed in the spacer body (22) to communicate between a gap (S) formed inside the seating groove (24) and the inside of the enclosure (32).

Description

Spacers for gas-insulated switchgear

[0001] The present invention relates to a spacer for a gas-insulated switchgear.

[0002] Gas-insulated switchgear (GIS) uses an insulating gas, with excellent insulation and arc-extinguishing properties, as an insulating medium within a sealed metal container (case). These gas-insulated switchgear utilize insulating gas to enhance the reliability of conductors and various devices located within the case, and are used in substations.

[0003] In a gas-insulated switchgear of this type, a spacer made of insulating material is placed at the joint between the enclosures to support a conductor passing between the enclosures. The conductor can extend between the enclosures by penetrating the spacer. The spacer is installed between the enclosures, and a seal is formed between the enclosures and the spacer to maintain airtightness. The spacer also serves to partition the enclosures.

[0004] The above spacer has a seating groove into which a seal used for sealing with the outer case is seated. When the seal is positioned in the seating groove, the surface of the seal is in close contact with one side of the outer case, thereby maintaining sealing between the spacer and the outer case.

[0005] The above seal is compressed while installed inside the above-mentioned mounting groove. Generally, if the seal fills the above-mentioned mounting groove to more than 90%, a gap is created between the spacer and the outer case, causing problems with current flow. Therefore, the seal fills the above-mentioned mounting groove to a value lower than 90%.

[0006] In this way, when the degree of filling of the seal in the seating groove is set to 90% or less, there may be a portion of the seating groove where the seal is not filled, and this portion may be filled with a gas having low insulation properties. This is because the work of filling the seating groove with the seal is performed in the air. In this way, when the space formed by the seating groove and the seal is filled with air having low insulation properties, even if a spacer is installed between the outer case, the outer case is made into a vacuum state, and an insulating gas is injected, the air having low insulation properties will remain in the seating groove.

[0007] Therefore, partial discharge may occur in the area where the low-insulating air is present, so it is necessary to remove this low-insulating air.

[0008] Prior art documents with the problems described above include Chinese Patent Publication No. 108631207, Japanese Patent Registration No. 7069434, and International Patent Application Publication No. WO2022 / 179765.

[0009] The purpose of the present invention is to solve the problems of the prior art as described above, and to allow insulating gas to fill the space within the mounting groove of a spacer used in a gas-insulated switchgear.

[0010] An object of the present invention is to prevent a seal positioned within a spacer's seating groove from being damaged by a gas connection.

[0011] The purpose of the present invention is to provide a seal that can be firmly fixed within a mounting groove formed in a spacer while still performing an airtight function.

[0012] The purpose of the present invention is to allow the introduction and discharge of insulating gas between the inside and outside of a mounting groove formed in a spacer to be made toward the inside of an outer case.

[0013] In order to achieve the above-described purpose, a spacer for a gas-insulated switchgear according to the present invention may include a spacer body forming a skeleton, a mounting groove formed around the edges of both surfaces of the spacer body and having a seal mounted therein, and a gas connection path formed on the inner wall of the mounting groove and the spacer body corresponding to the outside of the mounting groove so as to communicate between the mounting groove and the outside.

[0014] The above gas connection can be formed in multiple numbers at a predetermined interval.

[0015] The above gas connection can be formed on the inner wall of the center of the spacer body among the side walls of the above mounting groove.

[0016] In the above gas connection, the width of the bottom of the above-mentioned settling groove can be formed to be larger than the width of other parts.

[0017] The area of ​​the above gas connection opening toward the above mounting groove may be formed to be smaller than the cross-sectional area of ​​the above mounting groove.

[0018] The above-mentioned settling groove may include a press-fit portion into which the seal is pressed and an opening portion whose width gradually widens from the press-fit portion to the entrance of the above-mentioned settling groove.

[0019] The above press-fit portion may extend such that both side walls of the above mounting groove extend parallel to each other.

[0020] The width of the above-mentioned press-fit portion may be smaller than the width or diameter of the cross-section of the above-mentioned seal.

[0021] The spacer for a gas-insulated switchgear according to the present invention may have at least one of the following effects.

[0022] In the present invention, at least one gas connection path is formed in the spacer's mounting groove, thereby allowing communication between the interior of the housing and the mounting groove. Therefore, when the interior of the housing is vacuumed and insulating gas is injected, the insulating gas can be filled into any unfilled space within the mounting groove via the gas connection path. This effectively prevents partial discharge from occurring in the spacer.

[0023] In the present invention, the area where the gas connection opens into the mounting groove is made smaller than the cross-sectional area of ​​the mounting groove. Therefore, the seal located in the mounting groove is prevented from being moved by vacuum pressure toward the gas connection, which has an open area smaller than the cross-sectional area of ​​the mounting groove. This also prevents damage to the seal due to the gas connection.

[0024] In the present invention, the width near the entrance of the mounting groove is made larger than the width of the mounting groove near the bottom of the mounting groove, and the width of the mounting groove near the bottom of the mounting groove is made smaller than the width of the corresponding part of the seal, so that the seal can be maintained in a state of being pressed in near the bottom of the mounting groove, thereby more reliably performing the sealing function.

[0025] In the present invention, the gas connection path of the mounting groove is formed on the inner wall of the mounting groove, closer to the center of the spacer. Therefore, during vacuum operation and gas injection of the outer case, gas can be introduced and discharged into and from the unsealed space within the mounting groove through the gas connection path, thereby filling the space with insulating gas.

[0026] In the present invention, the width of the gas connection portion corresponding to the bottom of the mounting groove is made larger than the width of the opposite side of the gas connection. This allows for smoother communication between the gap formed in the mounting groove and the gas connection portion.

[0027] Figure 1 is a schematic cross-sectional view showing a spacer installed at the connection between the outer cases.

[0028] Figure 2 is a cross-sectional view showing that there is a space within the spacer's seating groove that is not filled by the seal.

[0029] Figure 3 is a front view showing the configuration of a spacer of an embodiment of the present invention.

[0030] Fig. 4 is a cross-sectional view taken along line 4-4' of Fig. 3.

[0031] Figure 5 is a cross-sectional view taken along line 5-5' of Figure 3.

[0032] Fig. 6 is a perspective view showing a gas connection formed in a spacer of an embodiment of the present invention.

[0033] Figure 7 is a working state diagram explaining that a spacer is assembled with a seal interposed on the flange of the outer case in an embodiment of the present invention.

[0034] Figure 8 is an explanatory drawing showing a space in which a seal is not filled when a spacer of an embodiment of the present invention is in close contact with a flange of an outer case with a seal interposed therebetween.

[0035] Figure 9 is an operational state diagram showing gas flowing in through a gas connection while the spacer of an embodiment of the present invention is in close contact with the flange of the outer case with a seal interposed therebetween.

[0036] Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. When designating components in each drawing, it should be noted that, where possible, identical components will be given the same reference numerals, even if they appear in different drawings. Furthermore, when describing embodiments of the present invention, if a detailed description of a related known structure or function is deemed to hinder understanding of the embodiments of the present invention, such detailed description will be omitted.

[0037] Additionally, terms such as first, second, A, B, (a), (b), etc. may be used to describe components of embodiments of the present invention. These terms are only intended to distinguish the components from other components, and the nature, order, or sequence of the components are not limited by the terms. When it is described that a component is "connected," "coupled," or "connected" to another component, it should be understood that the component may be directly connected or connected to the other component, but another component may also be "connected," "coupled," or "connected" between each component.

[0038] First, referring to FIGS. 1 and 2, it will be described that a spacer (10) is positioned between the outer cases (1, 1'). In general, when connecting the outer cases (1, 1') made in a cylindrical shape to each other, the spacer (10) is positioned between the flanges (3, 3') surrounding the edges of the outer cases (1, 1'). Then, a plurality of fastening holes (5) are fastened by penetrating the flanges (3, 3') and the spacer (10). In this way, the spacer (10) is fastened while being positioned between the outer cases (1, 1') so that the conductor (7) can be supported by the spacer (10). The conductor (7) is supported by penetrating the conductor through hole (13) penetrating the spacer (10).

[0039] A conductor hole (13) through which the conductor (7) passes is formed by penetrating the spacer body (11) that forms the skeleton of the spacer (10). A mounting groove (15) is formed around the edges of both surfaces of the spacer body (11) and a seal (17) is positioned therein. The seal (17) is pressed against the flange (3, 3') while being mounted in the mounting groove (15) to provide an airtight seal.

[0040] Meanwhile, FIG. 3 illustrates a front view of a spacer (20) according to an embodiment of the present invention. The spacer (20) is generally shaped like a disk. Of course, the spacer (20) may have a central portion convex on one side and concave on the other side, as illustrated in FIG. 1. The spacer body (22) forms the skeleton of the spacer (20). The spacer (20) is made of an insulating material.

[0041] A seating groove (24) is formed around the edges of both surfaces of the spacer body (22). Since the seating groove (24) is formed around the edges of the spacer body (22), it may have a circular shape. A seal (30) may be positioned in the seating groove (24). As can be seen in FIG. 4 or FIG. 5, the seating groove (24) may be divided into a press-fit section (25) and an expansion section (25'). The press-fit section (25) is a portion where a portion of the seal (30) is pressed in. The width of the seating groove (24) in the press-fit section (25) has a value smaller than the thickness or the diameter of the cross-section of the seal (30). The depth of the press-fit section (25) may be equal to or greater than the radius of the cross-section of the seal (30). The above-mentioned expansion section (25') is a section whose width gradually widens as it approaches the entrance of the above-mentioned settling groove (24). The width at the entrance of the above-mentioned settling groove (24), which is the end of the above-mentioned expansion section (26'), may be larger than the diameter of the cross-section of the above-mentioned seal (30).

[0042] There is at least one gas connection passage (26) on one inner surface of the above-described mounting groove (24). The gas connection passage (26) starts from the bottom of the above-described mounting groove (24) and extends toward the center of the spacer body (22). A portion of the surface portion of the spacer body (22) where the above-described mounting groove (24) is formed protrudes relatively compared to other portions of the spacer body (22). The gas connection passage (26) can be formed even through this protruding portion. In this way, when the spacer (20) is installed between the flanges (34) of the outer case (32), the interior of the outer case (32) and the interior of the above-described mounting groove (24) can be communicated through the gas connection passage (26).

[0043] The above gas connection paths (26) may be provided in multiple numbers at predetermined intervals. In the present embodiment, there are three gas connection paths (26). However, the number of gas connection paths (26) may be greater as long as it does not affect other performances of the spacer (20).

[0044] In order to relatively reduce the number of the above gas connection channels (26), the flow cross-sectional area or width of the inner portion of the above gas connection channels (26) can be increased. This is well illustrated in Fig. 6. It can be seen that the width of the bottom of the press-fit portion (25) in the above gas connection channel (26) is wider than the width of other portions of the gas connection channel (26). This is to ensure better communication with the gap (S) formed within the above mounting groove (24).

[0045] In the present invention, the area where the gas connection path (26) opens into the mounting groove (24) is smaller than the cross-sectional area of ​​the mounting groove (24). This is to prevent the seal (30) located in the mounting groove (24) from moving due to vacuum pressure toward the gas connection path (26) having an open area smaller than the cross-sectional area of ​​the mounting groove (24). That is, this is to prevent the seal (30) from protruding to the outside through the gas connection path (26) due to the vacuum pressure acting through the gas connection path (26) in the process of making the inside of the outer case (32) into a vacuum. For reference, the cross-sectional area of ​​the mounting groove (24) is related to the cross-sectional area of ​​the seal (30) mounted thereon.

[0046] A conductor hole (28) may be formed in the spacer body (22). The conductor hole (28) penetrates the spacer body (22). In the present embodiment, one conductor hole (28) is formed in the center. However, in the case of three phases, three conductor holes (28) may be formed. The number of conductor holes (28) may vary depending on design conditions.

[0047] A plurality of fastening holes (29) are formed on the edge of the above spacer body (22) through which fastening holes (not shown) pass. A fastening hole that passes through the flange (34) of the outer case (32) passes through the fastening holes (29).

[0048] The seal (30) above is formed in a ring shape in this embodiment so that it can be seated in the seating groove (24). The seal (30) is made of an elastic material. The cross-section of the seal (30) may be circular. The seal (30) is seated in the seating groove (24) and comes into close contact with the flange (34) of the outer case (32) to provide an airtight seal.

[0049] Meanwhile, the configuration of the outer case (32) is similar to that described in Fig. 1. In addition, the outer case (32) has a flange (34), which is used for fastening the outer cases (32) together. That is, the spacer (20) is installed between the flanges (34), which are the portions where two outer cases (32) are connected. With the edge of the spacer (20) secured between the flanges (34) of the outer case (32), the fastening hole passes through the flange (34) and the fastening hole (29) of the spacer body (22).

[0050] When the seal (30) is inserted into the mounting groove (24) of the spacer (20), a part of the seal (30) (the lower half based on the cross section of the seal (30)) is mounted by being pressed into the press-fit portion (25), and the remaining part of the seal (30) (the upper half based on the cross section of the seal (30)) protrudes outward from the entrance of the mounting groove (24). In this state, a gap (S) may be generated at the bottom of the mounting groove (24). That is, it is a space in the mounting groove (24) that is not filled with the seal (30). Air may remain in the gap (S) during the process of inserting the seal (30) into the mounting groove (24) in the atmosphere. However, in the present invention, the air in the gap (S) is removed through the gas connection (26) in the process of forming a vacuum inside the outer case (32), and in the process of filling the outer case (32) with insulating gas again, the insulating gas can enter the gap (S) through the gas connection (26).

[0051] Hereinafter, the use of a spacer for a gas-insulated switchgear according to the present invention having the configuration described above will be described in detail.

[0052] The spacer (20) of the present invention is positioned between the outer cases (32) that are connected to each other, and a portion of the mounting groove (24) is pressed against one surface of the flange (34) of the outer case (32) with the seal (30) interposed therebetween. This state is illustrated in Fig. 8.

[0053] The seal (30) is pressed into the seating groove (24) of the spacer (20) in the air. Even if the seal (30) is pressed into the press-fit portion (25), the seal (30) cannot be inserted to completely fill the entire press-fit portion (25). Therefore, the gap (S) is bound to occur, and air may remain in the gap (S). For reference, the gap (S) may mainly occur at the part where the side walls and the bottom of the press-fit portion (25) meet. Here, the side walls of the press-fit portion (25) have an inner wall adjacent to the center of the spacer (20) and an outer wall adjacent to the edge of the spacer (20). Therefore, a gap (S) may occur on each of the inner and outer walls of the press-fit portion (25), but the gap (S) formed on the outer wall does not need to be managed for partial discharge.

[0054] In the present invention, the gas connection path (26) formed in the spacer (20) can connect the gap (S) formed on the inner wall side of the press-fit portion (25) with the interior of the outer case (32). Therefore, in the process of forming a vacuum inside the outer case (32) while the adjacent outer cases (32) are joined, the air in the gap (S) can be discharged through the gas connection path (26).

[0055] After the interior of the outer case (32) is vacuumed, insulating gas is injected into the interior of the outer case (32) again. The insulating gas can be supplied and filled in the gap (S) formed on the inner wall side of the press-fit portion (25) through the gas connection path (26) in the direction of the arrow shown in Fig. 9. Accordingly, partial discharge can be prevented from occurring inside the mounting groove (24) formed in the spacer (20).

[0056] Even though all components constituting the embodiments according to the present invention have been described as being combined or operating in combination, the present invention is not necessarily limited to such embodiments. That is, within the scope of the purpose of the present invention, all components may be selectively combined and operated one or more times. In addition, terms such as "include," "comprise," or "have" described above, unless specifically stated to the contrary, mean that the corresponding component may be inherent, and therefore should be interpreted as including other components rather than excluding other components. All terms, including technical or scientific terms, have the same meaning as generally understood by a person of ordinary skill in the art to which the present invention pertains, unless otherwise defined. Commonly used terms, such as terms defined in a dictionary, should be interpreted as being consistent with the contextual meaning of the related technology, and shall not be interpreted in an ideal or overly formal sense, unless explicitly defined in the present invention.

[0057] The above description is merely an illustrative illustration of the technical idea of ​​the present invention, and those skilled in the art will appreciate that various modifications and variations can be made without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate, rather than limit, the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present invention.

Claims

A spacer body that forms a skeleton, A seating groove formed around the edges of both surfaces of the spacer body and into which a seal is seated; A spacer for a gas-insulated switchgear, comprising a gas connection path formed on the inner wall of the mounting groove and the spacer body corresponding to the outside of the mounting groove to perform communication between the mounting groove and the outside. In the first paragraph, a spacer for a gas-insulated switchgear, wherein a plurality of gas connection paths are formed at a predetermined interval. In the first paragraph, the gas connection path is a spacer for a gas-insulated switchgear formed on the inner wall of the center of the spacer body among the side walls of the mounting groove. In the first paragraph, a spacer for a gas-insulated switchgear, wherein the width of the bottom side of the mounting groove is formed to be larger than the width of other parts of the gas connection. A spacer for a gas-insulated switchgear, wherein, in the first paragraph, the area of ​​the gas connection path opening toward the mounting groove is formed to be smaller than the cross-sectional area of ​​the mounting groove. A spacer for a gas-insulated switchgear, wherein the mounting groove in the first paragraph includes a press-fit portion into which the seal is pressed and an opening portion whose width gradually widens from the press-fit portion to the entrance of the mounting groove. In the sixth paragraph, the press-fit portion is a spacer for a gas-insulated switchgear in which both side walls of the mounting groove extend parallel to each other. A spacer for a gas-insulated switchgear, wherein the width of the press-fit portion in the 7th paragraph is smaller than the width or diameter of the cross-section of the seal.

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