Switch cabinet and pressure relief device and pressure relief method thereof

Abstract

The invention discloses a switch cabinet and a pressure relief device and method thereof, the pressure relief device comprises a pressure relief channel, a cover plate, a gauze element, an elastic connecting piece and an arc blocking assembly, the cover plate is arranged on the pressure relief channel, the first side of the cover plate is hinged to a side plate of the pressure relief channel, and the gauze element is fixed on the cover plate; one end of each elastic connecting piece is fixed on the cover plate, and the other end of each elastic connecting piece is connected with a side plate of the pressure relief channel through a fixing block; each arc blocking assembly is located in the corresponding pressure relief channel and comprises an arc blocking plate, an elastic piece and a supporting frame. At least one end of the supporting frame is fixed to a side plate of the pressure relief channel, the arc blocking plate is movably installed below the supporting frame through the guide column, and the elastic piece is arranged on the guide column in a sleeving mode and located between the supporting frame and the arc blocking plate. And a plurality of through holes are formed in the arc baffle. Pressure accumulation in the cabinet body is avoided, and damage of impact energy sprayed out of the cabinet body to the environment outside the cabinet body is reduced.

Description

Technical Field

[0001] The invention belongs to the field of switch cabinet safety operation, and in particular relates to a switch cabinet and a pressure relief device and a pressure relief method thereof. Background Art

[0002] Switchgear is an electrical equipment that is opened, closed, controlled and protected during the power generation, transmission, distribution and energy conversion process of the power system. In the actual operation of the switchgear, internal arc faults often occur due to insulation aging, misoperation, foreign matter, overvoltage and line short circuit. When an arc fault occurs, high-temperature and high-pressure gas will be generated instantly. If these high-temperature and high-pressure gases cannot be effectively released in a very short time, the gas inside the cabinet will expand and the pressure will increase suddenly, which may cause the cabinet to burst under strong pressure and even cause a fire. Therefore, the relevant documents clearly require that each high-voltage compartment of the switchgear (such as the circuit breaker room, busbar room, and cable room) should be equipped with a pressure relief channel or pressure release device; when an arc fault occurs in the switchgear, the pressure relief channel or pressure release device should be able to be opened reliably, and the direction of pressure release should avoid the inspection channel and other equipment.

[0003] At present, the most commonly used pressure relief method for switch cabinets is to install a pressure relief cover on the top of each high-voltage compartment of the switch cabinet. One end of the pressure relief cover is fixed with a metal screw or hinge, and the other end is fixed with a nylon screw. When an arc fault occurs, the accumulated pressure causes the nylon screw to break, causing one side of the pressure relief cover to open and release the pressure. The connection of the metal screw or hinge on the other side prevents the pressure relief cover from flying up and injuring people. Figure 1 and Figure 2 The pressure relief structure of a single high-voltage compartment of the switch cabinet is shown, and the arrow indicates the flow direction of high-temperature and high-pressure gas and arc burning when a fault occurs; the pressure relief structure specifically includes a cabinet 1, a pressure relief channel 2, a hinge 3, a pressure relief cover plate 4, a nylon screw 5 and a steel wire mesh 6; the pressure relief channel 2 is fixed to the top of the cabinet, one end of the pressure relief cover plate 4 is connected to the pressure relief channel 2 through a hinge 3, and the other end is fixed to the pressure relief channel 2 through a nylon screw 5, and the steel wire mesh 6 is fixed to the pressure relief cover plate 4 through a pressure strip, and the switch cabinet can be ventilated and dissipated when it is working normally. When an arc burning fault occurs, the arc burning releases huge energy in a short time, causing the gas inside the cabinet to expand and the pressure to increase. The high-temperature and high-pressure gas and arc burning residue cannot be discharged in time through the steel wire mesh, so they impact the pressure relief cover plate, break the nylon screw, open one side of the pressure relief cover plate, release the pressure, and the hinge connection on the other side prevents the pressure relief cover plate from flying up and injuring people.

[0004] However, this most commonly used pressure relief method has the following problems:

[0005] (1) The strength of nylon screws is affected by materials, processing technology, temperature, etc., and is highly random. Generally, the pressure relief cover cannot be opened immediately in the event of an accident, which can easily cause pressure accumulation and have a significant impact on other equipment in the cabinet;

[0006] (2) The pressure relief cover is opened by accumulating high-temperature and high-pressure gas. The cover needs to be scrapped after the pressure relief. The broken and high-speed ejected nylon screws may cause harm to operators or equipment.

[0007] (3) When the high-temperature and high-pressure gas breaks through the pressure relief cover, the arc and its combustion residues in the switch cabinet are directly ejected to the outside of the cabinet without being blocked, which may damage surrounding equipment or cause harm to operators.

[0008] (4) The commonly used pressure relief methods do not effectively reduce the injection energy of high-temperature and high-pressure gas and arc combustion. Summary of the invention

[0009] The object of the present invention is to provide a switch cabinet and a pressure relief device and a pressure relief method thereof, so as to solve the shortcomings of the most commonly used pressure relief method.

[0010] The present invention solves the above technical problems through the following technical solutions: a pressure relief device for relieving pressure of pressurized gas inside a switch cabinet, the device comprising a pressure relief channel, a cover plate and a gauze, the cover plate is arranged on the pressure relief channel and a first side of the cover plate is hinged to a side plate of the pressure relief channel, and the gauze is fixed on the cover plate;

[0011] The device also includes at least one elastic connector and at least one arc-blocking assembly; one end of the elastic connector is fixed to the cover plate, and the other end of the elastic connector is connected to the side plate of the pressure relief channel through a fixing block; the arc-blocking assembly is located in the pressure relief channel and includes an arc-blocking plate, an elastic member and a support frame; at least one end of the support frame is fixed to the side plate of the pressure relief channel, and the arc-blocking plate is movably mounted above or below the support frame through a guide column, and the elastic member is sleeved on the guide column and is located between the support frame and the arc-blocking plate; a plurality of through holes are provided on the arc-blocking plate.

[0012] Furthermore, the number of the elastic connectors is 2, and the elastic connectors are tension springs; the two tension springs are close to the first side of the cover plate, and the two tension springs are respectively close to the second side and the third side of the cover plate; wherein the second side and the third side of the cover plate refer to the side adjacent to the first side of the cover plate.

[0013] Furthermore, the number of the elastic connecting members is 2, and the elastic connecting members are torsion springs; the two torsion springs are close to the first side of the cover plate, and the rotation axes of the two torsion springs are in the same direction as the rotation axis of the hinge.

[0014] Furthermore, the arc baffle plate is a concave-convex alternating plate.

[0015] Furthermore, a limit block for limiting the upward displacement of the arc baffle plate is provided on the side plate of the pressure relief channel.

[0016] Furthermore, the number of the arc blocking assemblies is 2, and one of the arc blocking assemblies is located above the other arc blocking assembly.

[0017] Furthermore, the arc-blocking plates of the two arc-blocking assemblies are both concave-convex alternating plates, and the concave portion of the concave-convex alternating plate of one arc-blocking assembly is staggered with the concave portion of the concave-convex alternating plate of the other arc-blocking assembly, or the convex portion of the concave-convex alternating plate of one arc-blocking assembly is staggered with the convex portion of the concave-convex alternating plate of the other arc-blocking assembly.

[0018] Furthermore, the first side of the cover plate is hinged to the side plate of the pressure relief channel through metal screws or hinges.

[0019] Based on the same concept, the present invention provides a switch cabinet, comprising a cabinet body, on which the pressure relief device as described above is provided.

[0020] Based on the same concept, the present invention provides a pressure relief method using the pressure relief device as described above, wherein the pressure relief device is arranged on the cabinet body of the switch cabinet, and the pressure relief method comprises:

[0021] When no arcing fault occurs in the cabinet, the cover is closed under the force of the elastic connector and the gravity of the cover;

[0022] When an arc fault occurs in the cabinet, the high-temperature and high-pressure gas and arcing residues in the cabinet impact the arc baffle plate of the arc baffle assembly, causing the arc baffle plate to move upward along the guide column. At the same time, the elastic part of the arc baffle assembly is stretched or compressed, consuming part of the impact energy; the impact energy passing through the through hole of the arc baffle plate acts on the cover plate, overcoming the force of the elastic connecting part and the gravity of the cover plate to open the cover plate, so that the high-temperature and high-pressure gas and part of the arcing residues are released outside the cabinet.

[0023] Beneficial Effects

[0024] Compared with the prior art, the advantages of the present invention are:

[0025] The cover plate of the present invention is hinged to the side plate of the pressure relief channel and is also connected to the side plate of the pressure relief channel through an elastic connector. When no arcing fault occurs, the cover plate is closed by the force of the elastic connector and the gravity of the cover plate. When an arcing fault occurs, the high-temperature and high-pressure gas only needs to overcome the smaller force of the elastic connector and the gravity of the cover plate to open the cover plate, so that the high-temperature and high-pressure gas in the switch cabinet is released in time, avoiding the pressure accumulation in the cabinet, and then avoiding the influence of pressure on other equipment in the cabinet, thereby protecting other equipment in the cabinet. The cover plate using an elastic connector can be opened and closed multiple times, is not easy to be damaged, and will not pop out broken nylon screws or other foreign objects, avoiding the possible damage to operators or equipment caused by popped-out nylon screws or other foreign objects.

[0026] The present invention arranges an arc blocking assembly including an arc blocking plate and an elastic member in the pressure relief channel. The arc blocking plate can effectively intercept arcing residues with larger sizes, thereby preventing the arcing residues with larger sizes from spraying out of the cabinet and causing damage to the environment outside the cabinet, and can also divide the arc into smaller and more fragmented small arcs, thereby accelerating the extinguishing speed of the arc and reducing the damage of the arc to the environment outside the cabinet. At the same time, by converting part of the impact energy of the high-temperature and high-pressure gas and the arcing residue into the elastic potential energy of the elastic member and overcoming the gravity of the arc blocking plate, the impact energy sprayed outside the cabinet is effectively weakened, thereby reducing the damage of the impact energy sprayed outside the cabinet to the environment outside the cabinet. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only one embodiment of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 It is a schematic diagram of a pressure relief structure in the background technology of the present invention;

[0029] Figure 2 It is a top view of the pressure relief structure in the background technology of the present invention;

[0030] Figure 3 is a front view of the installation of the elastic connecting member in the embodiment of the present invention;

[0031] Figure 4 is a top view of the installation of the elastic connector in an embodiment of the present invention;

[0032] Figure 5 Schematic diagram of the installation of the arc blocking assembly in the embodiment of the present invention;

[0033] Figure 6 is a schematic structural diagram of an arc baffle in an embodiment of the present invention;

[0034] Figure 7 Schematic diagram of the open state of the pressure relief device in an embodiment of the present invention.

[0035] Explanation of the reference numerals: 1-cabinet, 2-pressure relief channel, 3-hinge, 4-cover plate, 5-nylon screw, 6-mesh, 7-tension spring, 8-support frame, 9-guide column, 10-elastic member, 11-protrusion, 12-arc baffle, 13-limiting block, 14-mounting hole. DETAILED DESCRIPTION

[0036] The following is a clear and complete description of the technical solutions in the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] The technical solution of the present application is described in detail with specific embodiments below. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0038] like Figures 3 to 6 As shown, a pressure relief device provided by an embodiment of the present invention includes a pressure relief channel 2, a cover plate 4, a gauze 6, two elastic connectors and two arc-blocking assemblies. The cover plate 4 is arranged on the pressure relief channel 2 and the first side of the cover plate 4 is hinged to the side plate of the pressure relief channel 2. The gauze 6 is fixed to the cover plate 4; one end of each elastic connector is fixed to the cover plate 4, and the other end of each elastic connector is connected to the side plate of the pressure relief channel 2 through a fixing block; one of the two arc-blocking assemblies is located above the other, and each arc-blocking assembly is located in the pressure relief channel 2 and includes an arc-blocking plate 12, an elastic member 10 and a support frame 8; at least one end of the support frame 8 is fixed to the side plate of the pressure relief channel 2, and the arc-blocking plate 12 is movably installed above or below the support frame 8 through a guide column 9, and the elastic member 10 is sleeved on the guide column 9 and is located between the support frame 8 and the arc-blocking plate 12; a plurality of through holes are provided on the arc-blocking plate 12. In this embodiment, the elastic member 10 is a spring.

[0039] When the pressure relief device is installed on the cabinet 1 of the switch cabinet and there is no arcing fault in the cabinet 1, under the force of the elastic connector (including the pre-tension of the elastic connector and gravity) and the gravity of the cover 4, the cover 4 is closed (such as Figure 3 As shown), that is, the fourth side of the cover plate 4 contacts the pressure relief channel 2, and the fourth side of the cover plate 4 refers to the side opposite to the first side of the cover plate 4. When an arc fault occurs in the cabinet 1, as shown in FIG. Figure 7As shown, the high-temperature and high-pressure gas and arc-burning residues in the cabinet 1 impact the arc-baffle plates 12 of the two arc-baffle assemblies in turn, causing the arc-baffle plates 12 of the two arc-baffle assemblies to move upward along the guide column 9, and at the same time, the elastic members 10 of the two arc-baffle assemblies are compressed to consume part of the impact energy; the impact energy that passes through the arc-baffle plates 12 of the two arc-baffle assemblies in turn acts on the cover plate 4, overcoming the force of the elastic connecting member and the gravity of the cover plate 4 to open the cover plate 4, so that the high-temperature and high-pressure gas and part of the arc-burning residues are automatically released to the outside of the cabinet 1, and the larger arc-burning residues are effectively intercepted by the arc-baffle plates 12 of the two arc-baffle assemblies.

[0040] In a specific embodiment of the present invention, Figure 4 As shown, the two elastic connectors are tension springs 7, the two tension springs 7 are close to the first side of the cover plate 4, and the two tension springs 7 are close to the second side and the third side of the cover plate 4 respectively; wherein the second side and the third side of the cover plate 4 refer to the side adjacent to the first side of the cover plate 4. The two tension springs 7 are close to the first side and the second side, the first side and the third side of the cover plate 4 respectively, and while shortening the length of the tension springs 7, it is easier to open the cover plate 4, so that the high-temperature and high-pressure gas in the switch cabinet body 1 is released more timely, and the pressure accumulation in the cabinet body 1 is avoided.

[0041] In another specific embodiment of the present invention, the two elastic connecting members are torsion springs; the two torsion springs are close to the first side of the cover plate 4, and the rotation axes of the two torsion springs are in the same direction as the rotation axis of the hinge.

[0042] In a specific embodiment of the present invention, Figure 6 As shown, the arc-blocking plates 12 of each arc-blocking assembly are concave-convex plates. The use of concave-convex plates helps to better divide the arc, making the arc length passing through the arc-blocking plate 12 smaller and more fragmented, further accelerating the extinguishing speed of the arc. The use of multiple arc-blocking assemblies can more effectively intercept arc residues, better divide the arc, and reduce impact energy.

[0043] The convex part 11 of the concave-convex interlaced plate is provided with a mounting hole 14, and the bolt passes through the mounting hole 14 on the concave-convex interlaced plate to connect with the support frame 8. In order to ensure the balance of the arc blocking assembly, each arc blocking assembly is equipped with at least two support frames 8, such as Figure 5 As shown, the upper arc-blocking assembly includes two support frames 8, and the lower arc-blocking assembly includes three support frames 8. In this embodiment, each support frame 8 is a U-shaped support frame.

[0044] In a specific embodiment of the present invention, Figure 5 As shown, a limit block 13 for limiting the upward displacement of the arc baffle plate 12 is provided on the side plate of the pressure relief channel 2. A limit block 13 is configured at both ends of each arc baffle plate 12.

[0045] In a specific embodiment of the present invention, Figure 5As shown, the concave part of the concave-convex interlaced plate of one of the two arc-blocking assemblies is staggered with the concave part of the other concave-convex interlaced plate, or the convex part 11 of the concave-convex interlaced plate of one of the two arc-blocking assemblies is staggered with the convex part 11 of the other concave-convex interlaced plate. That is, the concave part of the arc-blocking plate 12 of the upper arc-blocking assembly corresponds to the convex part 11 of the arc-blocking plate 12 of the lower arc-blocking assembly, and the convex part 11 of the arc-blocking plate 12 of the upper arc-blocking assembly corresponds to the concave part of the arc-blocking plate 12 of the lower arc-blocking assembly. This arrangement helps to better divide the arc, making the arc length passing through the arc-blocking plate 12 smaller, more fragmented, and more dispersed, further accelerating the extinguishing speed of the arc.

[0046] In a specific embodiment of the present invention, the first side of the cover plate 4 is hinged to the side plate of the pressure relief channel 2 via a metal screw or hinge 3 .

[0047] In a specific embodiment of the present invention, the pressure relief channel 2 is surrounded by a front side plate, a rear side plate, a left side plate, and a right side plate. Exemplarily, the side plate hinged to the first side of the cover plate 4 is the left side plate, the side plate opposite to the left side plate is the right side plate, and the other two side plates are the front side plate and the rear side plate. The second side and the third side of the cover plate 4 correspond to the front side plate and the rear side plate, respectively, and the fourth side of the cover plate 4 corresponds to the right side plate. One of the fixing blocks corresponding to the two elastic connectors can be arranged on the left side plate or the front side plate, and the other fixing hole can be arranged on the left side plate or the rear side plate; one end of the support frame 8 is fixed to the front side plate or the rear side plate, or the two ends of the support frame 8 are respectively fixed to the front side plate and the rear side plate; the two limit blocks 13 of each arc baffle plate 12 are respectively arranged on the left side plate and the right side plate.

[0048] The embodiment of the present invention further provides a pressure relief method using the pressure relief device as described above, wherein the pressure relief device is arranged on a cabinet body 1 of a switch cabinet, and the pressure relief method comprises:

[0049] When no arcing fault occurs in the cabinet 1, the cover plate 4 is closed under the force of the elastic connector and the gravity of the cover plate 4, that is, the fourth side of the cover plate 4 contacts the top of the right side plate of the pressure relief channel 2;

[0050] When an arc fault occurs in the cabinet 1, the high-temperature and high-pressure gas and arcing residues in the cabinet 1 impact the arc baffle plates 12 of the two arc-blocking assemblies in turn, causing the arc baffle plates 12 to move upward along the guide column 9. At this time, part of the impact energy needs to be consumed to overcome the weight of the arc baffle plates 12 and provide driving force; at the same time, the elastic member 10 of the arc-blocking assembly is stretched (the arc baffle plates 12 are located above the support frame 8) or compressed (the arc baffle plates 12 are located below the support frame 8), converting part of the impact energy into elastic potential energy; the impact energy that passes through the through holes of the arc baffle plates 12 in turn acts on the cover plate 4, overcoming the force of the elastic connecting member and the gravity of the cover plate 4 to open the cover plate 4, allowing the high-temperature and high-pressure gas and part of the arcing residues to be released outside the cabinet 1.

[0051] What is disclosed above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or modifications within the technical scope disclosed in the present invention, which should be covered within the protection scope of the present invention.

Claims

1. A pressure relief device for relieving pressure of pressurized gas inside a switch cabinet, the device comprising a pressure relief channel, a cover plate and a gauze, the cover plate being arranged on the pressure relief channel and a first side of the cover plate being hinged to a side plate of the pressure relief channel, the gauze being fixed on the cover plate; characterized in that: The device also includes at least one elastic connector and at least one arc-blocking assembly; one end of the elastic connector is fixed to the cover plate, and the other end of the elastic connector is connected to the side plate of the pressure relief channel through a fixing block; the arc-blocking assembly is located in the pressure relief channel and includes an arc-blocking plate, an elastic member and a support frame; at least one end of the support frame is fixed to the side plate of the pressure relief channel, and the arc-blocking plate is movably mounted above or below the support frame through a guide column, and the elastic member is sleeved on the guide column and is located between the support frame and the arc-blocking plate; a plurality of through holes are provided on the arc-blocking plate.

2. The pressure relief device according to claim 1, characterized in that: The number of the elastic connectors is 2, and the elastic connectors are tension springs; the two tension springs are close to the first side of the cover plate, and the two tension springs are respectively close to the second side and the third side of the cover plate; wherein the second side and the third side of the cover plate refer to the side adjacent to the first side of the cover plate.

3. The pressure relief device according to claim 1, characterized in that: The number of the elastic connecting members is 2, and the elastic connecting members are torsion springs; the two torsion springs are close to the first side of the cover plate, and the rotation axes of the two torsion springs are in the same direction as the rotation axis of the hinge.

4. The pressure relief device according to claim 1, characterized in that: The arc baffle plate is a concave and convex plate.

5. The pressure relief device according to claim 1, characterized in that: A limit block for limiting the upward displacement of the arc baffle plate is provided on the side plate of the pressure relief channel.

6. The pressure relief device according to any one of claims 1 to 5, characterized in that: The number of the arc blocking assemblies is 2, and one of the arc blocking assemblies is located above the other arc blocking assembly.

7. The pressure relief device according to claim 6, characterized in that: The arc-blocking plates of the two arc-blocking assemblies are both concave-convex alternating plates, and the concave portion of the concave-convex alternating plate of one arc-blocking assembly is staggered with the concave portion of the concave-convex alternating plate of the other arc-blocking assembly, or the convex portion of the concave-convex alternating plate of one arc-blocking assembly is staggered with the convex portion of the concave-convex alternating plate of the other arc-blocking assembly.

8. The pressure relief device according to any one of claims 1 to 5, characterized in that: The first side of the cover plate is hinged to the side plate of the pressure relief channel through metal screws or hinges.

9. A switch cabinet, comprising a cabinet body, characterized in that: The cabinet is provided with a pressure relief device as claimed in any one of claims 1 to 8.

10. A pressure relief method using the pressure relief device according to any one of claims 1 to 8, wherein the pressure relief device is arranged on a switch cabinet, characterized in that: The pressure relief method comprises: When no arcing fault occurs in the cabinet, the cover is closed under the force of the elastic connector and the gravity of the cover; When an arc fault occurs in the cabinet, the high-temperature and high-pressure gas and arcing residues in the cabinet impact the arc baffle plate of the arc baffle assembly, causing the arc baffle plate to move upward along the guide column. At the same time, the elastic part of the arc baffle assembly is stretched or compressed, consuming part of the impact energy; the impact energy passing through the through hole of the arc baffle plate acts on the cover plate, overcoming the force of the elastic connecting part and the gravity of the cover plate to open the cover plate, so that the high-temperature and high-pressure gas and part of the arcing residues are released outside the cabinet.

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