switchgear

Abstract

To address a problem that, if a rear surface cover of a switch gear is reinforced by, for example, providing a reinforcement member in order to give strength to withstand a pressure increase caused by an internal arc, the workability is degraded due to an increase of the weight, and a problem that, when the rear surface cover is split, high-temperature and high-pressure gas may leak from a gap generated between split parts.SOLUTION: A rear surface cover is formed of a plurality of cover parts to be engaged with each other, and an engagement portion of each of the cover parts is formed into a shape having a section obtained by overlapping L-like bent portions. Accordingly, a gap between the engagement portions is not generated, leakage of high-temperature and high-pressure gas caused by occurrence of an internal arc can be prevented, and the workability of removing and attaching the cover is improved.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present application relates to a switchgear. [Background technology]

[0002] A switchgear has a rear cover on the rear of its housing. The role of the rear cover in a switchgear is to protect workers from electric shock when they come into contact with live parts and to prevent short-circuit accidents caused by small animals or foreign objects entering the switchgear. For this reason, conventional rear covers are formed from a single sheet of metal, and only need to have a structure that covers and conceals the space on the rear of the housing to prevent people or small animals from entering the switchgear from the outside to the inside (see, for example, Patent Document 1). Furthermore, the rear cover is designed to weigh 20 kg or less so that it can be removed by one person during assembly, maintenance, and inspection of the switchgear. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6714108 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if an internal arc occurs due to an abnormal operating condition or a malfunction within the switchgear, the conventional back cover, which is formed from a single piece of metal and has no reinforcing members, is weak and cannot withstand the increased pressure. This can cause the back cover to break or deform, allowing high-temperature, high-pressure gas to leak from the gap between the back cover and the housing, potentially spraying high-temperature, high-pressure gas onto workers.

[0005] On the other hand, if reinforcing members were installed or the thickness of the members were increased to provide the strength to withstand the pressure increase caused by the internal arc, the weight of the rear cover would exceed 20 kg, making it difficult to work with.Furthermore, simply dividing the rear cover to reduce the weight to 20 kg or less would create gaps in the divided areas, which could allow high-temperature, high-pressure gas to leak out.

[0006] Furthermore, the standard for metal-enclosed switchgear, JIS C 62271-200:2021, enacted in July 2021, has been harmonized with IEC 62271-200:2011, strengthening safety regulations. This is expected to increase requirements for internal arc protection. Therefore, the role of the back cover is expected to be to protect workers from live parts, improve workability during assembly, and be strong enough to withstand pressure increases caused by internal arcs.

[0007] The present application has been made to solve the above-mentioned problems, and aims to provide a switchgear having a back cover that can prevent the outflow of high-temperature, high-pressure gas due to the occurrence of an internal arc and improves the workability of installation and removal. [Means for solving the problem]

[0008] The switchgear disclosed in the present application comprises: The inside of the housing is divided into a plurality of compartments, and at least a circuit breaker and a cable are arranged in each compartment, The cover attached to the rear of the housing and covering the compartment is composed of a plurality of cover parts that engage with each other, and the engaging part of each cover part is formed in a shape that includes a part where L-shaped bent parts are overlapped. The overlapping L-shaped bent portions extend in the direction of the installation surface of the switchgear. It is characterized by the presence of [Effects of the Invention]

[0009] The switchgear disclosed in the present application can eliminate gaps that occur when multiple cover parts are engaged, can prevent the leakage of high-temperature, high-pressure gas due to the generation of internal arcs, and improves the workability of removing and attaching the cover. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a side view of a switchgear according to a first embodiment. [Figure 2] 2 is an enlarged view of the rear cover shown in area A of FIG. 1. FIG. [Figure 3] FIG. 3 is an enlarged view of region X in FIG. 2. [Figure 4] FIG. 3 is a rear view taken along line BB in FIG. 2. [Figure 5] FIG. 3 is a front view taken along line CC in FIG. 2. [Figure 6] FIG. 2 is a side view of the upper part of the rear cover according to the first embodiment. [Figure 7] FIG. 4 is a side view of the lower part of the rear cover according to the first embodiment. [Figure 8] FIG. 10 is a rear view of a rear cover of the switchgear according to the second embodiment. [Figure 9] FIG. 9 is a plan view taken along the line DD in FIG. 8. [Figure 10] FIG. 10 is a front view taken along the line EE in FIG. 9. [Figure 11] FIG. 10 is a diagram illustrating the arrangement inside a cable compartment of a switchgear according to a second embodiment. [Figure 12] FIG. 11 is a side view of a rear cover of the switchgear according to the third embodiment. [Figure 13] FIG. 13 is a front view taken along the line FF in FIG. [Figure 14] FIG. 13 is a rear view taken along line GG in FIG. 12. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, preferred embodiments of the switchgear according to the present invention will be described with reference to the drawings. The same reference numerals are used to designate the same contents and corresponding parts, and detailed descriptions thereof will be omitted. Similarly, in the following embodiments, redundant descriptions of components with the same reference numerals will be omitted.

[0012] Embodiment 1 1 is a side view of the switchgear in embodiment 1, FIG. 2 is an enlarged view of the rear cover shown in area A of FIG. 1, FIG. 3 is an enlarged view of area X of FIG. 2, FIG. 4 is a rear view seen from line BB of FIG. 2, FIG. 5 is a front view seen from line CC of FIG. 2, and FIGS. 6 and 7 are side views of the rear cover upper part 1 and the rear cover lower part 2 that constitute the rear cover of FIG. 2.

[0013] 1, the switchgear 100 is, for example, a metal-clad or compartment-type switchgear entirely covered with a grounded metal housing, the interior of which is divided into multiple compartments. Each compartment, consisting of a circuit breaker compartment 10 having circuit breakers 101 and 102, a busbar compartment 11, an upper cable compartment 12, and a lower cable compartment 13, is separated by a partition plate 14 made of grounded metal or an insulator.

[0014] The left side of Fig. 1 is the front of the switchgear 100, where doors 103 and 104 are provided, and the doors 103 and 104 are opened to pull out the circuit breakers 101 and 102 and to operate an operation panel (not shown). The right side of Fig. 1 is the rear of the switchgear, where a rear cover is attached and covers the upper cable compartment 12 and the lower cable compartment 13.

[0015] The rear cover is configured by engaging two separate cover sections, an upper rear cover section 1 and a lower rear cover section 2, as shown in Figure 2. The engaging section between the upper rear cover section 1 and the lower rear cover section 2 is formed by overlapping the respective bent sections 3, as shown in Figure 3. Details will be explained later in Figures 6 and 7.

[0016] As shown in Fig. 4, reinforcing members 4 are attached to the periphery of the rear side of the upper rear cover 1 and the lower rear cover 2 facing the inside of the switchgear, thereby reinforcing the cover so that it does not deform, such as by bending or twisting, or break when an internal arc occurs. Furthermore, the reinforcement can be increased by connecting the reinforcing members 4 around the periphery of the upper rear cover 1 with reinforcing members 41. The reinforcing members 4 and 41 use steel material with an L-shaped cross section as shown in Fig. 2, but the cross section may also be concave or square.

[0017] 5, a reinforcing member 42 is fixed to the periphery of the rear cover upper part 1 and rear cover lower part 2 on the side opposite the rear side (front side). The reinforcing member 42 may be any shape, such as a plate, L-shape, or square shape. The reinforcing members 4, 41, and 42 do not all need to be attached to a single rear cover, but can be appropriately selected and attached depending on the material of the rear cover, the capacity of the circuit breaker, and other factors, taking into account the occurrence of an internal arc. Note that the reinforcing member 42 is omitted from the illustrations of FIGS. 2, 6, and 7.

[0018] As shown in Figure 3, at the dividing portion 5 between the upper back cover 1 and the lower back cover 2, as shown in Figures 6 and 7, the ends of the upper back cover 1 and the lower back cover 2 are bent into an L-shape to form a bent portion 3, and these are then overlapped to form an engagement portion. In order to overlap the bent portion 3, the lengths of the L-shaped bottoms extending from the covers are made different between the upper back cover 1 and the lower back cover 2. The end of the back cover other than the dividing portion 5 is bent on the back side to form a bent portion 6.

[0019] In this way, the rigidity of the rear cover can be strengthened by attaching the reinforcing members 4, 41, and 42, forming an engagement portion by overlapping the bent portion 3 in the divided portion 5, and by the bent portion 6 at the rear cover end. This gives the rear cover the strength to withstand a pressure increase caused by an internal arc. In other words, even if a pressure increase occurs due to an internal arc, it is possible to prevent high-temperature, high-pressure gas from leaking out from between the rear cover and the housing due to damage or deformation of the rear cover.

[0020] In particular, by forming L-shaped bent portions 3 at the ends of the upper back cover 1 and the lower back cover 2 of the divided portion 5 and overlapping these bent portions 3 to form an engaging portion, it is possible to eliminate gaps that occur when engaging, and to reliably prevent the leakage of high-temperature, high-pressure gas. Even if a gap does occur, the gas will blow out in the direction of the installation surface of the switchgear 100, and will not be directed toward the worker. Furthermore, overlapping the L-shaped bent portions 3 makes it easy to position the upper back cover 1 and the lower back cover 2 relative to each other. The angle of the L-shape may be an acute angle or an obtuse angle, and the shape may include an L-shaped bent portion, for example, a shape in which the end of the L-shaped bent portion is further bent.

[0021] Furthermore, by configuring the rear cover as two separate cover sections, upper and lower, the weight of the cover can be reduced during installation. This allows the weight to be kept below 20 kg even when reinforcing members 4, 41, 42, etc. are attached to the rear cover, making it possible for one person to remove the rear cover, improving the workability of installing and removing the cover.

[0022] Embodiment 2 8 is a rear view of the rear cover of the switchgear in the second embodiment as seen from inside the housing, FIG. 9 is a plan view as seen from line DD in FIG. 8, and FIG. 10 is a front view as seen from line EE in FIG.

[0023] The rear cover of the switchgear of embodiment 1 is divided perpendicular to the height direction (horizontally), whereas the switchgear of this embodiment has a structure in which the rear cover is divided in the height direction (vertically) as shown in FIG. 8, and similar to embodiment 1, bending portions 3 bent in an L shape as shown in FIG. 9 are provided at the ends facing the dividing portion 5 of the rear cover left part 7 on the left side when viewed from the front side in FIG. 10 and the rear cover right part 8 on the right side.

[0024] As shown in Fig. 8, a reinforcing member 4 is provided near the edge on the rear side of the rear cover, and a bent portion 6 is formed on the rear side by bending the ends of the rear cover right portion 8 and rear cover left portion 7 other than the dividing portion 5. Furthermore, as shown in Fig. 10, a reinforcing member 42 is fixed to the periphery on the front side of the rear cover. Note that the reinforcing member 42 is omitted from Fig. 9.

[0025] The rear cover of the switchgear configured in this manner not only achieves the effects of embodiment 1, but also satisfies the LSC2B-PI / PM standard of JIS C 62271-200:2021. That is, LSC2B-PI / PM is one of the compartment and partition classes for the interior of a panel, and specifies a structure in which high-voltage compartments such as circuit breaker compartment 10, busbar compartment 11, upper cable compartment 12, and lower cable compartment 13 shown in Figure 1 are separated by insulating and metal partition plates 14, preventing access to the high-voltage compartments during operation.

[0026] If the rear cover is divided horizontally as in embodiment 1, when there is a cable 15 from another high-voltage compartment in the lower cable compartment 13 as shown in Figure 11, the rear cover of the lower cable compartment 13 cannot be removed while the upper cable compartment 12 is operating.

[0027] In contrast, by dividing the rear cover vertically as in this embodiment, it is possible to remove only the left rear cover section 7, even if there are cables from other high-voltage compartments in operation inside the lower cable compartment 13 shown in Figure 11. This makes it possible to perform maintenance and inspection on the high-voltage compartment that has experienced a power outage, even while some high-voltage compartments are in operation. This allows the LSC2B-PI / PM to be satisfied.

[0028] Embodiment 3 12 is a side view of the rear cover of the switchgear in the third embodiment, FIG. 13 is a front view of the rear cover taken along line FF in FIG. 12, and FIG. 14 is a rear view of the rear cover taken along line GG in FIG.

[0029] As shown in Figures 12 to 14, the switchgear of this embodiment has a structure in which the rear cover is divided into three parts: an upper rear cover part 1, an intermediate rear cover part 9, and a lower rear cover part 2. The ends of each rear cover facing the divided part between the upper rear cover part 1 and the intermediate rear cover part 9 and the ends of each rear cover facing the divided part between the intermediate rear cover part 9 and the lower rear cover part 2 are bent in the same L-shape as described in embodiment 1, and the ends other than the divided parts have a bent part 6 formed on the rear side by bending. In addition, as shown in Figures 13 and 14, reinforcing members 4, 41 are attached to the periphery of the rear and front sides of the rear cover.

[0030] By dividing the rear cover into three parts, the weight of each rear cover can be reduced compared to the first embodiment.

[0031] Although the present application describes various exemplary embodiments and examples, the various features, aspects, and functions described in one or more embodiments are not limited to application to a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are conceivable within the scope of the technology disclosed in the present specification, including, for example, cases where at least one component is modified, added, or omitted, and cases where at least one component is extracted and combined with components of another embodiment. [Explanation of symbols]

[0032] 1: Upper part of rear cover, 2: Lower part of rear cover, 3: Bent part, 4: Reinforcement member, 5: Split part, 6: Bent part, 7: Left part of rear cover, 8: Right part of rear cover, 9: Middle part of rear cover, 10: Circuit breaker compartment, 11: Busbar compartment, 12: Upper cable compartment, 13: Lower cable compartment, 14: Partition plate, 41, 42: Reinforcement member, 101, 102: Circuit breaker, 103, 104: Door.

Claims

1. A switchgear in which the interior of a housing is divided into a plurality of compartments, and at least a circuit breaker and a cable are arranged in each compartment, A switchgear characterized in that a cover attached to the rear surface of the housing and covering the compartment is composed of multiple cover parts that engage with each other, the engaging parts of each cover part are formed in a shape that includes a portion where L-shaped bent parts are overlapped, and the overlapped L-shaped bent parts extend in the direction of the installation surface of the switchgear.

2. The switchgear according to claim 1, wherein the plurality of cover portions have engaging portions formed in a direction perpendicular to a height direction of the housing.

3. The switchgear according to claim 2, wherein the plurality of cover portions are two pieces, an upper piece and a lower piece.

4. The switchgear according to claim 2, wherein the plurality of cover portions are three pieces: an upper cover portion, a middle cover portion, and a lower cover portion.

5. The switchgear according to claim 1 , wherein the plurality of cover portions are formed with engagement portions in a height direction of the housing.

6. The switchgear according to claim 5, wherein the plurality of cover portions are two cover portions, a right cover portion and a left cover portion.

7. 7. The switchgear according to claim 1, wherein reinforcing members are attached to both the rear side and the front side of the cover portion to provide strength sufficient to withstand a pressure increase caused by an internal arc.

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