Metal enclosure for electrical switchgear

Abstract

The invention relates to a metal enclosure (100, 200) for an electrical switching device, the metal enclosure being configured to be pressurized above atmospheric pressure, the metal enclosure comprising: a metal wall (102, 104, 106, 108, 110, 111) sealing the periphery of at least two volumes (118, 119) for accommodating different groups of electrical switching devices; and at least one partition wall (116, 216) separating the volume spaces for different groups of electrical switching devices, the at least one partition wall being attached to the outer peripheral metal wall of the respective volume space defined by the respective at least one partition wall, where the at least one partition wall protrudes to the outside of the outer periphery of the metal wall.

Description

Technical Field

[0001] The present invention relates to a metal enclosure for an electrical switching device. Background Art

[0002] The metal enclosure used for gas insulated switchgear encloses the switchgear in a pressurized environment. A gas is selected to provide electrical insulation inside the metal enclosure, a common gas is SF6, but other gases are also available, such as dry air, N2, CO2, or a mixture of two or three of N2, O2, CO2.

[0003] The dielectric resistance of the gas is proportional to the pressure inside the metal capsule. Therefore, it is advantageous to increase the pressure of the gas inside the metal capsule. However, this means that the metal capsule wall must be able to withstand the forces generated by the increased pressure.

[0004] Therefore, it is desirable to increase the ability of metal enclosures for gas insulated switchgear to withstand higher pressures, as explained in detail below. Summary of the invention

[0005] In view of the above and other shortcomings of the prior art, an object of the present invention is to provide a metal enclosure that at least partially alleviates the deficiencies of the prior art.

[0006] According to a first aspect of the present invention, a metal enclosure for an electrical switching device is provided, which is configured to be pressurized to a pressure higher than atmospheric pressure, and comprises: a metal wall that seals the periphery of at least two volume spaces for accommodating different groups of electrical switching devices; at least one partition wall that separates the volume spaces for different groups of electrical switching devices, the at least one partition wall being attached to the peripheral metal wall of the corresponding volume space defined by the corresponding at least one partition wall, wherein the at least one partition wall protrudes outside the periphery of the metal wall.

[0007] The present invention is based at least in part on the realization of providing a dividing wall that acts as a bulkhead / diaphragm within a metal enclosure. The dividing wall greatly increases the pressure resistance of the entire metal enclosure. With a dividing wall attached to a metal wall, the force that attempts to push out one wall is used to hold the opposing wall in place. To further improve this effect, the dividing wall completely cuts through the metal wall.

[0008] Tolerating higher pressures is particularly important when switching to dry air, N2, CO2, or a mixture of any two or three of these as dielectric gases. These gases require higher pressures to provide adequate insulation without increasing the distances between phases and components of the switchgear compared to the more environmentally unfriendly alternative gases such as SF6. Despite the switch to a different gas, it is desirable to maintain the size of the metal enclosure, or at least not increase it.

[0009] Generally speaking, in electrification and gas-insulated switchgear (GIS), if the gas pressure in a metal enclosure exceeds 1.5 bar absolute pressure, the enclosure can be called a high-voltage enclosure according to known standards. If so, it must pass the relevant pressure routine tests, which makes traditional enclosures bulky and quite expensive. Therefore, the filling pressure of the medium voltage (MV)-GIS discussed in this article is usually <1.5 bar absolute pressure, for example, in the range of 1.0-1.5 bar absolute pressure. Advantageously, the metal enclosure disclosed in this article is suitable for a filling pressure of 1.0-4.0 bar absolute pressure, preferably for a filling pressure of 1.5-3.0 bar absolute pressure. In other words, the pressure is increased compared to the traditional 1.0-1.5 bar absolute pressure range without the need for bulky and oversized enclosure walls.

[0010] According to one embodiment, at least one metal wall may be corrugated. The corrugated metal wall improves the strength of the metal wall, thereby increasing the pressure resistance of the metal enclosure.

[0011] According to one embodiment, the partition wall may include a protrusion along the perimeter of the partition wall, wherein the protrusion cuts through the metal wall to extend outside the metal enclosure. The protrusion may be a tab that passes through the wall to achieve a secure connection (eg by welding to the metal wall).

[0012] According to one embodiment, the partition walls may extend outside the metal capsule on four sides of the metal capsule. That is, the four walls may be firmly anchored, whereby the force of each pair of walls is used to hold the opposing wall in place. Overall, the pressure resistance is improved.

[0013] According to one embodiment, the entire periphery of the partition wall extends to the outside of the metal capsule. Therefore, the partition wall is larger than the outer periphery of the outer metal wall, so that the entire periphery is visible from the outside of the metal capsule. In this way, a more secure anchoring can be achieved and the pressure resistance can also be improved.

[0014] According to one embodiment, the metal enclosure may include at least two metal enclosure modules, each of which includes a metal wall that seals the periphery of a volume space, and a partition wall located between adjacent metal enclosure modules. In other words, a modular metal enclosure is provided. In addition, each partition wall may have a metal enclosure module welded to one side of the partition wall and another metal enclosure module welded to the opposite side, wherein the entire periphery of the partition wall extends to the outside of the metal enclosure module. That is, two modules are welded to opposite sides of a single partition wall.

[0015] According to one embodiment, the partition wall may be welded to the peripheral metal wall. That is, the metal wall may define the outermost periphery. Preferably, the weld is located on the outside of the metal wall.

[0016] According to one embodiment, at least one peripheral metal wall is a corrugated sheet. The corrugated sheet increases the strength of the sheet and thus also increases the pressure resistance.

[0017] According to one embodiment, the longitudinal axis of the corrugations may be orthogonal to the main plane of the partition wall.

[0018] According to one embodiment, the thickness of the partition wall may be in the range of 1 mm to 5 mm, preferably 1 mm to 3 mm.

[0019] According to one embodiment, at least one dividing wall can comprise an opening connecting adjacent volumes. This provides, for example, gas circulation between the volumes for cooling.

[0020] According to one embodiment, the outer wall and the partition wall of the metal capsule may be made of steel, which is a high-strength material that can improve the ability of the metal capsule to withstand internal pressure.

[0021] According to a second aspect of the present invention, there is provided a gas insulated switchgear, comprising: a group of electrical switches; and a metal enclosure according to any one of the preceding embodiments pressurized by gas.

[0022] Other effects and features of the second aspect of the present invention are very similar to the effects and features described above in conjunction with the first aspect of the present invention.

[0023] Further features and advantages of the present invention will become apparent when studying the appended claims and the following description. Those skilled in the art realize that different features of the present invention can be combined to create embodiments other than those described in the following, without departing from the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] These and other aspects of the present invention will now be described in more detail with reference to the accompanying drawings showing exemplary embodiments of the present invention, in which:

[0025] Figure 1 is a perspective view of the front side of a metal capsule according to an embodiment of the present invention;

[0026] Figure 2 yes Figure 1 A perspective view of the rear side of the metal capsule in FIG.

[0027] Figure 3 yes Figure 1 and Figure 2 An exploded view of the metal capsule in FIG.

[0028] Figure 4 is a perspective view of the front side of a metal capsule according to an embodiment of the present invention;

[0029] Figure 5 yes Figure 4 a perspective view of the rear side of the metal capsule in FIG.

[0030] Figure 6 yes Figure 4 and Figure 5 Exploded view of the metal capsule in FIG. DETAILED DESCRIPTION

[0031] In the detailed description herein, various embodiments of the present invention are described herein with reference to specific embodiments. When describing the embodiments, specific terms are used for clarity. However, the present invention is not limited to the selected specific terms. Although specific exemplary embodiments are discussed, it should be understood that this is for illustrative purposes only. Those skilled in the relevant art will recognize that other components and configurations may be used without departing from the scope of the present invention.

[0032] Figure 1 1 shows a front view of a metal enclosure 100 for an electrical switching device according to one embodiment, Figure 2 A rear view of the metal capsule 100 is shown. The metal capsule 100 is configured to be pressurized above atmospheric pressure.

[0033] The metal enclosure 100 includes metal walls 102, 104, 106, 108, 110, 111 that seal the perimeters of at least two volumes for accommodating different groups of electrical switching devices.

[0034] The metal walls comprise a first metal wall 102, which is arranged opposite to a second metal wall 110. Preferably, the walls 102, 104, 106, 108, 110, 111 of the metal enclosure are made of steel.

[0035] Furthermore, third wall 108 disposed as a metal plate on the top side of metal enclosure 100 is connected to first metal wall 102 and second metal wall 110, for example, by welding. Third metal wall 108 includes corrugations 114 and is also preferably connected to side walls 104 and 106 by welding in this embodiment.

[0036] An elongated metal reinforcement rib 115 is attached to the outer side 118 of the first metal wall 102. There may be a set of elongated reinforcement ribs attached to the outer side 118 of the first metal wall 102, in which case the elongated metal reinforcement ribs are substantially parallel to each other.

[0037] Furthermore, the second metal wall 110 is also corrugated. A corrugated wall or plate includes corrugations defining valleys and ridges in the plate.

[0038] Figure 3 yes Figure 1 and Figure 2 Exploded view of the metal enclosure 100 in FIG. The metal enclosure comprises at least one partition wall 116 which separates two volume spaces 118 and 119 for different groups of electrical switching devices.

[0039] The at least one partition wall 116 is attached to the peripheral metal wall 102, 108, 110, 111 of the respective volume space 118, 119 defined by the respective at least one partition wall 116. The at least one partition wall 116 protrudes outside the periphery of the metal wall 102, 108, 110, 111. The partition wall 116 preferably protrudes through the thickness of the metal wall 102, 108, 110, 111.

[0040] In the present embodiment, the partition wall 116 includes a protrusion 120 or tab along the perimeter of the partition wall. The protrusion 120 cuts through the metal wall 102, 108, 110, 111 to extend outside the metal enclosure 100.

[0041] In other words, the metal walls 102, 108, 110, 111 have appropriate through holes 122 through which the protrusions 120 can be inserted and welded to the outer surface of each metal wall 102, 108, 110, 111. The welding can be spot welding in the through holes 122 in which the protrusions 120 are located.

[0042] Preferably, the partition wall 116 extends on four sides of the metal capsule 100 outside the metal capsule 100. Here, the four sides are the first metal wall 102, the second metal wall 110 opposite to the first metal wall 102, the top plate 108 and the opposite bottom plate 111. Therefore, the protrusion 120 can be seen from the outside of the capsule 100.

[0043] The bottom plate 111 preferably comprises at least one corrugation 114. The longitudinal axis 114a of the corrugation 114 of any or all of the metal walls is orthogonal to the main plane 116a of the partition wall 116.

[0044] At least one of the dividing walls 116 includes an opening 124 connecting adjacent volumes.

[0045] Figure 4 2 shows a front view of a metal enclosure 200 for an electrical switching device according to one embodiment. Figure 5 A rear view of the metal capsule 200 is shown. The metal capsule 200 is configured to be pressurized above atmospheric pressure.

[0046] The metal enclosure 200 includes metal walls 202 a - b , 204 , 206 , 208 a - b , 210 a - b , 211 a - b that seal the perimeters of at least two volumes 218 and 220 for accommodating a plurality of sets of electrical switching apparatus 170 .

[0047] The metal enclosure 200 comprises at least one partition wall 216 which separates two volumes 218 and 220 for different groups of electrical switching devices. The entire periphery 217 of the partition wall 216 extends outside the metal enclosure 200.

[0048] The metal enclosure 200 is modular, including a first metal enclosure module 200a and a second metal enclosure module 200b. Each metal enclosure module includes a metal wall sealing the periphery of a volume space, and a partition wall 216 located between adjacent metal enclosure modules.

[0049] Figure 6 yes Figure 4 and Figure 5 Exploded view of the metal enclosure 200 in FIG. The metal enclosure includes at least one partition wall 216 that separates two volume spaces 218 and 220 for different groups of electrical switching devices.

[0050] More specifically, the first metal enclosure module 200a includes metal walls 202a, 208a, 210a, 211a, and the second metal enclosure module 200b includes metal walls 202b, 208b, 210b, 211b.

[0051] The metal walls 202a-b, 208a-b, 210a-b and 211a-b of the respective metal enclosure modules 200a-b include a first metal wall 202a, 202b arranged opposite to the second metal wall 210a, 210b and a third metal wall 208a, 208b arranged opposite to the fourth metal wall 211a, 211b. Preferably, the walls 202a-b, 208a-b, 210a-b and 211a-b and the side walls 204 and 206 of the metal enclosure modules are made of steel and can be provided as metal plates. In addition, here, the walls 210a, 210b, 211a, 211b and 208a, 208b are corrugated plates.

[0052] The third walls 208 a , 208 b are provided as metal plates located at the top side of the metal enclosure 200 .

[0053] At least one dividing wall 216 includes an opening 224 connecting adjacent volumes 218 and 220 .

[0054] The partition wall 216 has a metal enclosure module 200a welded to one side 230a of the partition wall 216 and another metal enclosure module 200b welded to the opposite side 230b of the partition wall 216. For example, the metal walls 202a, 208a, 210a and 211a are welded to a first planar side 230a of the partition wall 216, and the metal walls 202b, 208b, 210b and 211b are welded to a second planar side 230b of the partition wall 216. The first side 230a is opposite to the second side 230b with respect to the main plane of the partition wall 216 set as the plane of the plate.

[0055] Preferably, the weld is located on the outer perimeter 240 of the metal walls 202a-b, 208a-b, 210a-b, and 211a-b.

[0056] In an embodiment, the corrugations 214 extend along a longitudinal axis 214 a , which may be orthogonal to a major plane 216 a of the partition wall 216 .

[0057] The outer walls and the dividing walls of the metal enclosure described herein may be made of steel and may be provided as plates with or without corrugations.

[0058] The thickness of the partition wall described herein may range from 1 mm to 5 mm, preferably from 1 mm to 3 mm.

[0059] See also Figure 1 and Figure 4 , a gas insulated switchgear 10, 20 is also provided, which includes a set of electrical switches 170 and a metal enclosure 100, 200 pressurized by gas. The switch can be a 10-52kV switch, preferably a 12 / 24 / 36, 40.5kV switch. The switch can be, for example, CC, CCV, CCF, CCCC, etc., where C: cable switch module, De: direct cable connection with earthing module (Direct cable connection with earthing module), D: direct cable connection module (Direct cable connection module), F: switch-fuse disconnectormodule (Switch-fuse disconnectormodule), V: vacuum circuit breaker module. Preferably, the gas in the metal enclosure is dry air, N2, CO2 or a mixture of any two or three of N2, O2, CO2.

[0060] Even though the invention has been described above with reference to specific exemplifying embodiments, many different alterations, modifications and the like will become apparent for those skilled in the art.

[0061] Furthermore, variations of the disclosed embodiments may be understood and effected by those skilled in the art in practicing the claimed invention by studying the drawings, the disclosure and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The fact that certain measures are stated in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Claims

1. A metal enclosure (100, 200) for an electrical switching device, the metal enclosure being configured to be pressurized to a pressure above atmospheric pressure, the metal enclosure comprising: A metal wall (102, 104, 106, 108, 110, 111) sealing the periphery of at least two volumes (118, 119) for accommodating a plurality of sets of electrical switching devices, At least one partition wall (116, 216) separates volume spaces for different groups of electrical switching devices, and the at least one partition wall is attached to the outer peripheral metal wall of the corresponding volume space defined by the corresponding at least one partition wall, wherein the at least one partition wall protrudes on four sides of the metal enclosure outside the outer periphery of the metal wall.

2. The metal capsule according to claim 1, wherein: At least one of the metal walls is corrugated.

3. The metal capsule according to any one of claims 1 and 2, wherein: The partition wall includes a protrusion (120) along a periphery of the partition wall, wherein the protrusion cuts through the metal wall to extend to the outside of the metal enclosure.

4. The metal capsule according to any one of claims 1 and 2, wherein: The entire periphery (217) of the partition wall extends outside the metal capsule.

5. The metal capsule (200) according to any one of claims 1 and 2, comprises at least two metal capsule modules (200a, 200b), each of which comprises a metal wall (202a-b, 208a-b, 210a-b, 211a-b) sealing the periphery of a volume space and a partition wall located between adjacent metal capsule modules.

6. The metal capsule according to claim 5, wherein: Each partition wall has a metal enclosure module welded to one side (230a) of the partition wall and another metal enclosure module welded to the opposite side (230b), wherein the partition wall extends with its entire periphery outside the metal enclosure module.

7. The metal capsule according to any one of claims 1 and 2, wherein: The partition wall is welded to the metal wall.

8. The metal capsule according to claim 7, wherein: The weld is located on the outer periphery of the metal wall.

9. The metal capsule according to any one of claims 1 and 2, wherein: At least one of the peripheral metal walls is a corrugated sheet.

10. The metal capsule according to claim 9, wherein: The longitudinal axis of the corrugations is orthogonal to the main plane of the partition wall.

11. The metal capsule according to any one of claims 1 and 2, wherein: The thickness of the partition wall is in the range of 1 mm to 5 mm, preferably in the range of 1 mm to 3 mm.

12. The metal capsule according to any one of claims 1 and 2, wherein: The at least one dividing wall includes an opening (124, 224) connecting adjacent volumes.

13. The metal capsule according to any one of claims 1 and 2, wherein: The outer wall and the partition wall of the metal enclosure are made of steel.

14. A gas insulated switchgear (10, 20), comprising: a set of electrical switches (170); as well as A metal capsule (100, 200) according to any one of claims 1 and 2 pressurized by a gas.

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