Structure of a power distribution panel

Abstract

This device safely discharges hot gases from distribution panels caused by short circuits and other accidents using a simple structure, ensuring the safety of surrounding workers. [Solution] The inside of the distribution panel enclosure is divided into multiple compartments 12 to 14. Pressure relief plates 16 that open and close in accordance with pressure changes in the compartments 12 to 14 are provided at the openings of these compartments 12 to 14. The enclosure also includes a pressure relief chamber 18 communicating with the openings and a pair of front and rear pressure relief frames 19 arranged within the pressure relief chamber 18. Openings 19d are formed on the sides of the pressure relief frames 19. A reinforcing plate 20 with a group of ventilation holes is installed on the front pressure relief frame 19, and a louver plate 21 is installed on the rear pressure relief frame 19. The reinforcing plate 20 is provided with a pair of double-opening pressure relief plates 22 on the front and rear sides of the ventilation holes, and a single-opening pressure relief plate 23 is supported at the rear of the louver plate 23.

Description

Technical Field

[0001] The present invention relates to a housing structure of a switchboard that discharges (emits) hot gas generated by a short - circuit accident or the like.

Background Art

[0002] Closed switchboards and the like have a structure in which the inside of a grounded metal box is partitioned into a plurality of compartments, and main circuit components such as circuit breakers, buses, and connecting conductors are housed in each compartment.

[0003] When an internal arc accident accompanied by the generation of an arc due to a short - circuit accident or the like occurs in each compartment, the internal pressure of the compartment rises, and there is a risk that arc gas will be discharged from the housing, door, monitoring window, etc.

[0004] In addition, when an internal arc accident occurs in the compartment, the components housed in the compartment may generate high - temperature decomposition products that are gasified or vaporized, and there is also a risk that they will be discharged outside the compartment.

[0005] Therefore, as shown in Patent Document 1, for closed switchboards such as switchgears, a structure for reducing the released gas pressure has been proposed in order to reduce the momentum of the high - temperature decomposition products released from the compartment to the outside.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Non - Patent Documents

[0007]

Non - Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] When switchgear with an internal arc grade (IAC) is housed, the structure must ensure worker safety even in the event of a short circuit. In particular, the emitted gas (hot gas) containing high-temperature decomposition products during a short circuit is generally discharged to the top of the distribution panel enclosure, but the force of the discharge is tremendous and it is necessary to consider the possibility of it bouncing off the ceiling.

[0009] In this case, the structure of Patent Document 1, as shown in Figure 6(a), is provided with ducts 4 that communicate with each compartment of the housing 1. With this structure, in the event of an internal arc accident, the pressure relief plate 5 at the top of the compartment opens, and the discharged hot gas is guided to a shared pressure relief chamber 2. The pressure relief frame 3 disperses the force, and the attenuated hot gas is released to the top of the housing 1. However, as shown by the hot gas G3 in Figure 6(b), since it is discharged in a vertical direction, it tends to accumulate in the corners of the ceiling 9 and the rear wall 10, which is hardly safe.

[0010] Therefore, Non-Patent Document 1, as shown in Figure 7(a), employs a structure in which a pair of front and rear louver plates 8 are attached to the upper outlet of the pressure relief frame 3, thereby discharging the hot gas to the front (front side) rather than the rear where the hot gas tends to accumulate.

[0011] Although this structure yielded some results, when vortices were generated in the flow of hot gas, as shown in Figure 7(b) for hot gas G2, there was a risk that it could reach a location where workers might be present. Under certain conditions, this could compromise worker safety, and the expected effects could not be achieved.

[0012] Furthermore, there are often concerns about the presence of an opening above the switchgear inside the enclosure 1, and a structure is desired that allows for the control of hot gas discharge and also enables the opening to be closed.

[0013] This invention was made to address such conventional demands, and aims to solve the problem of safely discharging hot gases from a power distribution panel caused by short-circuit accidents, etc., with a simple structure, thereby ensuring the safety of surrounding workers. [Means for solving the problem]

[0014] (1) The present invention comprises a housing divided into a plurality of compartments, The structure of a power distribution panel for discharging hot gas from the compartment, A pressure relief plate is provided at the opening of the compartment and opens and closes in accordance with the pressure change inside the compartment, A pressure relief chamber communicating with the aforementioned opening, A pressure relief frame placed in the aforementioned pressure relief chamber, A grid-like reinforcing plate is installed on one side of the pressure relief frame and has ventilation holes formed therein to guide the hot gas upwards to the housing, A louver plate installed on the other side of the pressure relief frame, The reinforcing plate is provided with a pair of double-opening pressure-relieving plates on either side of the group of ventilation holes, A single-opening pressure relief plate is supported on the other side of the louver plate, with the one side open, Equipped with, A path for guiding and discharging the hot gas upward from the reinforcing plate between the group of ventilation holes and the double-opening pressure relief plates, The louver plate and the single-opening pressure relief plate provide a path for inducing and discharging the hot gas to one side of the housing, It has, The discharge from both of the aforementioned paths is combined, resulting in a gradual flow to one of the paths.

[0015] (2) Other aspects of the present invention are: Inside the aforementioned pressure relief chamber, A pair of the aforementioned pressure relief frames are arranged, The reinforcing plate is installed on the pressure relief frame on one side. The louver plate is installed on the pressure relief frame on the other side. It is characterized by the following.

[0016] (3) Further aspects of the present invention are: The pair of pressure release plates are provided in a slanting manner facing each other on one side and the other side of the ventilation hole group, respectively.

[0017] (4) Still another aspect of the present invention is that The pressure relief frame is formed in a concave cross-section, and includes a bottom surface portion and both side surface portions, and openings are formed in the both side surface portions, The hot gas flowing from the partition chamber into the pressure relief chamber hits the bottom surface portion, and after the flow is blocked at one end, it wraps around the side surface portion and enters the pressure relief frame from the opening, and the hot gas in the pressure relief frame is discharged by the both paths, which is characterized in that.

[0018] (5) In the case of a row board configuration using a plurality of the housings, the pressure relief chambers of the respective housings are communicated, and the hot gas in any one of the housings can be dispersed and discharged to the pressure relief chambers of the respective housings.

Effect of the Invention

[0019] According to the present invention, the hot gas of the switchboard generated by a short circuit accident or the like can be safely discharged with a simple structure, and the safety of the surrounding workers can be ensured.

Brief Description of the Drawings

[0020] [Figure 1] A longitudinal sectional view showing the main configuration of the structure of the switchboard according to the embodiment. [Figure 2] An exploded perspective view of the same. [Figure 3] A perspective view of the upper part of the housing. [Figure 4] A longitudinal sectional view showing the discharge state of the hot gas. [Figure 5] An image view of the same. [Figure 6] (a) is a perspective view of the switchboard of Patent Document 1, and (b) is a diagram showing the discharge state of the hot gas of (a). [Figure 7](a) is an upper perspective view of the power distribution panel from Non-Patent Document 1, and (b) is a diagram showing the heat gas discharge situation in (a). [Modes for carrying out the invention]

[0021] The structure (panel structure) of a switchboard according to an embodiment of the present invention will be described below. This switchboard is configured as a closed-type switchboard as described above, and by combining a simple structure, it controls the flow of hot gas generated by short-circuit accidents and other incidents to the upper front of the enclosure, thereby ensuring the safety of workers around the enclosure. [Examples]

[0022] An embodiment of the distribution panel will be described based on Figures 1 to 5. In Figure 1, 11 indicates the grounding metal housing (metal box) of the distribution panel.

[0023] <<Example Configuration>> As shown in Figure 1, the inside of the enclosure 11 is divided into several compartments 12 to 14. Here, as an example, compartments 12 to 14 are designated as the circuit breaker room (VCB room) 12, the busbar room 13, and the cable room 14. The circuit breaker room 12 is located on the front side (front side: arrow F side) of the distribution panel and houses, for example, switchgear with an internal arc grade (IAC). Note that 15 in Figure 1 indicates a relay box in which controllers and other equipment are housed.

[0024] Behind the circuit breaker room 12 (rear side: arrow B side), there is a busbar room 13 where, for example, a three-phase busbar is installed. This busbar is connected to the main circuit terminal of the disconnecting section connected to one end of the circuit breaker.

[0025] Behind the busbar chamber 13 is a cable chamber 14 where the load-side cables are housed. These cables are connected to the main circuit terminal of the disconnecting section connected to the other end of the circuit breaker.

[0026] Each of the compartments 12 to 14 is provided with an openable and closable pressure relief plate 16 at its upper end opening 12a to 14a to exhaust the hot gas from within the compartments 12 to 14. Furthermore, the upper part of the housing 11 is provided with a discharge structure to expel the hot gas exhausted from the compartments 12 to 14 to the outside of the housing 11.

[0027] To explain in detail, the top plate (not shown) of the housing 11 is formed in a frame shape, and as shown in Figure 1, a pressure relief chamber 18 is provided above the pressure relief plate 16 of the compartments 12 to 14. This pressure relief chamber 18 communicates with the inside of each of the compartments 12 to 14 when the pressure relief plate 16 opens, and hot gas from the compartments 12 to 14 flows into the pressure relief chamber 18. Note that Figure 1 shows the state when the pressure relief plate 16 is in the open position, and ventilation with the compartments 12 to 14 may be made possible by attaching a mesh to the pressure relief plate 16.

[0028] In this configuration, a pair of front and rear pressure relief frames 19 are arranged within the pressure relief chamber 18. The front pressure relief frame 19 is equipped with a grid-shaped reinforcing plate 20, the rear pressure relief frame 19 is equipped with a louver plate 21, a pair of double-opening pressure relief plates 22 are provided on the reinforcing plate 20, and a single-opening pressure relief plate 23 is supported on the rear side of the louver plate 21. The reinforcing plate 20, louver plate 21, and pressure relief plates 22 and 23 are installed on the opening (external discharge section) of the top plate.

[0029] (1) Pressure relief frame 19 As shown in Figures 1 and 2, each pressure relief frame 19 is formed in a U-shape in cross-section and has a bottom plate (bottom surface) 19a, side plates (side surfaces) 19b erected on both sides of the bottom plate 19a, mounting pieces 19c bent outward from the upper end of each side plate 19b, and a horizontally elongated rectangular opening 19d formed in each side plate 19b, through which the hot gas from the pressure relief chamber 18 enters the pressure relief frame 19.

[0030] Furthermore, each mounting piece 19c of the front and rear pressure relief frames 19 has three female screw holes c1 and c2, each at equal intervals (in Figure 2, the reference numerals for the female screw holes c1 and c2 on the mounting piece 19c on one side are omitted).

[0031] (2) Reinforcement plate 20 As shown in the figure, the reinforcing plate 20 is formed in a roughly square shape, and has a group of ventilation holes 25 that discharge hot gas that has entered the front pressure relief frame 19 to the upper part of the housing 1, and as described above, it has a grid-like structure.

[0032] This group of ventilation holes 25 is formed in a "4 rows and 4 columns" configuration, with holes d1 communicating with female screw holes c1 formed on both sides of the group of ventilation holes 25, while female screw holes d2 are formed on the front and back sides of the group of ventilation holes 25 (in Figure 2, the reference numerals for the holes d1 on one side and the female screw holes d2 on the rear side are omitted).

[0033] At this time, a first through-hole (not shown) communicating with the female screw hole c1 and hole d1 is formed at the opening edge of the top plate, and the shaft portion of bolt B1 (see Figure 3), which is inserted through hole d1 and the first through-hole, is fastened together with the female screw hole c1. In this way, the reinforcing plate 20 and the front pressure relief frame 19 are attached to the top plate.

[0034] (3) Louver plate 21 The louver plate 21 is formed in a roughly rectangular shape and is equipped with a group of vanes 26 that guide and discharge hot gas that has entered the rear pressure relief frame 19 to the front of the housing 1. That is, as shown in Figure 3, a plurality of vents 26b are formed parallel to each other at equal intervals, and vanes 26a are bent downward from each vent 26b.

[0035] Holes d3 communicating with female screw holes c2 are formed on both sides of the vane group 26, while a female screw hole d4 is formed on the rear side of the vane group 26 (the reference numeral for the hole d3 on one side is omitted in Figure 2).

[0036] Here, a second through-hole is formed in the opening edge of the top plate, communicating with the female screw hole c2 and hole d3. The shaft of a bolt B3, which is inserted through hole d3 and the second through-hole, is fastened to the female screw hole c2, thereby securing the louver plate 21 and the rear pressure relief frame 19 to the top plate.

[0037] (2) Pressure relief plates 22, 23 Each pressure relief plate 22, as shown in Figures 2 and 3, has a flat body 22b and a bent mounting piece 22a at the lower end of the body 22b. The mounting piece 22a has a hole f1 that communicates with a female screw hole d2, and the two pressure relief plates 22 are attached to the reinforcing plate 20 in a double-opening manner by fastening the shafts of bolts B2, which are inserted through the front and rear holes f1, to the female screw holes d2.

[0038] At this time, the main bodies 22b of both pressure relief plates 22 face each other at an inclined angle, guiding the hot gas discharged by the ventilation holes 25 directly above the housing 11. In Figure 3, the inclination angles of each main body 22b are different, but as shown in Figure 1, each main body 22b may be at the same inclination angle, and the inclination angle can be adjusted as appropriate depending on the installation environment of the housing 11.

[0039] The pressure relief plate 23 has a flat body 23b, similar to the pressure relief plate 22, and a bent mounting piece 22a formed at the lower end of the body 23b. However, the pressure relief plate 23 is larger than the pressure relief plate 22. In addition, a hole f2 is formed in the mounting piece 23a that communicates with the female screw hole d4, and the pressure relief plate 23 is cantilevered to the rear of the louver plate 21 (the rear side of the slat group 26) by fastening the shaft of a bolt B4 inserted through the hole f2 to the female screw hole d4.

[0040] In particular, because the pressure relief plate 23 is large, the main body 23b is positioned above the vane group 26, which prevents the hot gas discharged from the vent 26b from circulating around to the rear (back side) of the housing 11.

[0041] <<Emission of hot gases>> (1) When an internal arc accident occurs in each compartment 12-14, such as a short circuit, the internal pressure rises and hot gas (arc gas) is released. This causes the pressure relief plate 16 to open, and the hot gas flows into the pressure relief chamber 18, as shown by arrow P1 in Figure 1.

[0042] Here, the hot gas that flows into the pressure relief chamber 18 hits the bottom plate 19a of the pressure relief frame 19, temporarily blocking its flow and preventing it from being discharged outside the panel. After that, it flows around to the side plate 19b and enters the front and rear pressure relief frames 19 through the opening 19d.

[0043] As shown by arrow P3 in Figure 5, the hot gas that enters each pressure relief frame 19 rises towards the reinforcing plate 20 and the louver plate 21, respectively, and is discharged through two paths.

[0044] First, to explain the discharge path of the hot gas that enters the front pressure relief frame 19, the hot gas rises towards the reinforcing plate 20 and is then guided upward by the ventilation holes 25 and both pressure relief plates 22 and exhausted. That is, after flowing upward through the ventilation holes 25 of the reinforcing plate 20, it rises while being guided along the inner surfaces of both pressure relief plates 22 and is discharged from between the two pressure relief plates 22 to the top (approximately directly above) the housing 1, as shown by arrow P4.

[0045] Next, regarding the discharge path of the hot gas that has entered the rear pressure relief frame 19, the hot gas rises towards the louver plate 21, is guided by the inclination of the vane group 26, and is discharged from the vent 26b toward the front of the housing 11, as shown by arrow P5. In this case, as mentioned above, since the main body 23b of the pressure relief plate 23 is positioned above the vane group 26, the hot gas is prevented from circulating to the rear (back side) of the housing 11. In this respect, the accumulation of hot gas G1 in the corners of the ceiling 9 and the rear wall 10, as shown in Figure 6(b), is prevented.

[0046] As a result, as shown in Figure 4, the hot gas discharged approximately directly above the housing 1 (arrow P4) and the hot gas discharged to the front of the housing 1 (arrow P5) are combined to form a relatively gentle flow of hot gas G3 towards the front of the housing 1. In other words, by controlling the discharge to the front of the housing 11 (arrow P5) with the discharge approximately directly above the housing 11 (arrow P4), the spread of hot gas G2 due to vortex generation as shown in Figure 7(b) is suppressed.

[0047] Therefore, according to this embodiment, the hot gas G3 does not reach locations where workers may be present, and even under harsh conditions that could not be achieved with conventional structures, it is possible to protect surrounding workers from the hot gas and ensure their safety.

[0048] Since simple bending components 19-23 are used, the hot gas generated in the power distribution panel due to short-circuit accidents can be safely discharged with a simple structure, and costs can be reduced compared to conventional products such as those described in Patent Document 1 and Non-Patent Document 1.

[0049] Furthermore, by making the reinforcing plate 20 lattice-shaped, it is possible to suppress the ejection of more than 60g of flying debris (for example, components inside the panel) outside the panel during a short-circuit accident. This not only satisfies the standards for internal arc testing, but also ensures sufficient strength when working at heights on the panel.

[0050] Furthermore, the enclosure 11 of this embodiment can ensure a protection rating of "JIS C 0920" (IP4X) with the uppermost pressure relief plates 22 and 23. In this sense, the structure that allows control over the discharge of hot gases closes the opening (external discharge section), and is expected to eliminate concerns about the opening being above the conventional switchgear.

[0051] In particular, since the aforementioned protection level can be ensured, there are no restrictions on the openings (ventilation holes 25 and ventilation openings 26b) between the reinforcing plate 20 positioned inside the pressure relief plate 22 and the louver plate 21 positioned inside the pressure relief plate 23, and it can be manufactured at a lower cost than the structure in Non-Patent Document 1.

[0052] (2) The pressure relief chamber (the space from the pressure relief plate 16 in each compartment 12 to 14 to the uppermost pressure relief plates 22 and 23) 18 functions as a room (device) that temporarily absorbs the expansion pressure propagated through the pressure relief plate 16. The larger the volume of such a room, the greater the effect of mitigating the aforementioned expansion pressure.

[0053] Therefore, when a panel is configured with multiple housings 11, it is preferable to increase the pressure relief effect by connecting the pressure relief chambers 18 of adjacent housings 11 in communication with each other. In this case, as shown by arrow P1 in Figure 5, when hot gas is released into the pressure relief chamber 18 from compartments 12-14 where a short-circuit fault has occurred, it hits the bottom plate 19a of the pressure relief frame 19 and branches out in the left-right direction (LB direction).

[0054] A portion of the hot gas that is branched here enters the opening 19d, as shown by arrow P2, and is discharged through the path indicated by arrows P3 to P5. The remaining hot gas flows into the pressure relief chamber 18 of the adjacent housing 11, as shown by arrows P6 and P7, and is discharged from there through the path indicated by arrows P3 to P5. This allows the hot gas from the housing 11 where the short-circuit fault occurred to be distributed and discharged into the pressure relief chamber 18 of the adjacent housing 11.

[0055] It should be noted that the present invention is not limited to the embodiments described above, and can be implemented with modifications within the scope of each claim. For example, the housing 11 may be divided into a plurality of compartments, and is not limited to the circuit breaker room 12, busbar room 13, and cable room 14. [Explanation of Symbols]

[0056] 11…Cabinet 12-14... Compartments 16, 22, 23… pressure relief plates 18… Pressure relief chamber 19… Pressure relief framework 19a…Bottom part 19b...Side part 19d...Opening 20…Reinforcement plate 21... Louvered panels

Claims

1. It has an enclosure divided into multiple compartments, The structure of a power distribution panel for discharging hot gas from the compartment, A pressure relief plate is provided at the opening of the compartment and opens and closes in accordance with the pressure change inside the compartment, A pressure relief chamber communicating with the aforementioned opening, A pressure relief frame placed in the aforementioned pressure relief chamber, A grid-like reinforcing plate is installed on one side of the pressure relief frame and has ventilation holes formed therein to guide the hot gas upwards to the housing, A louver plate installed on the other side of the pressure relief frame, The reinforcing plate is provided with a pair of double-opening pressure-relieving plates on either side of the group of ventilation holes, A single-opening pressure relief plate is supported on the other side of the louver plate, with the one side open, Equipped with, A path for guiding and discharging the hot gas upward from the reinforcing plate between the group of ventilation holes and the double-opening pressure relief plates, The louver plate and the single-opening pressure relief plate provide a path for inducing and discharging the hot gas to one side of the housing, It has, A switchboard structure characterized in that the discharge from both of the aforementioned paths is combined and flows slowly to one of the aforementioned paths.

2. Inside the aforementioned pressure relief chamber, A pair of the aforementioned pressure relief frames are arranged, The reinforcing plate is installed on the pressure relief frame on one side. The louver plate is installed on the pressure relief frame on the other side. The structure of the switchboard according to claim 1, characterized in that it is as described above.

3. The pair of pressure-relieving plates are The ventilation holes are provided in an opposing inclined manner on one side and the other side of the aforementioned ventilation hole group. The structure of the switchboard according to claim 1, characterized in that it is as described above.

4. The aforementioned pressure relief frame is It is formed in a concave shape in cross-section, It has a bottom and two side parts, Openings are formed on both of the aforementioned side surfaces. The hot gas that flowed from the compartment into the pressure relief chamber was After the flow is interrupted at one point upon contact with the bottom surface, it flows around to the side surface and enters the pressure relief frame through the opening. The structure of the switchboard according to claim 3, characterized in that the hot gas within the pressure relief frame is discharged through both of the aforementioned paths.

5. In the case of a panel configuration consisting of multiple enclosures, The pressure relief chambers of each of the aforementioned housings are connected in communication. The hot gas in any of the housings is dispersed and discharged into the pressure relief chambers of each housing. The structure of a power distribution board according to any one of claims 1 to 5.

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