An SVG unit structure

Abstract

An electrical control box and SVG unit structure, the electrical control box includes an electrically insulating box body, and also includes a board, one or more of an AC busbar assembly and a DC busbar assembly; the board is arranged in the box body, including one or more of a drive board, a monitoring board and a power board, and the boards are connected by pin type and / or connector type; the AC busbar assembly and the DC busbar assembly are installed at the lower part of the box body, one end of the AC busbar and the DC busbar is located outside the box body, and the other end extends out of the box body, and the extension length is greater than the length inside the box; an insulating baffle is arranged between the DC busbars; the SVG unit structure also includes a power component, a capacitor bin component, a laminated busbar, an air duct component and a busbar, and the device has the ability to adapt to the harsh environment of high-altitude areas, and at the same time, it is also generally adaptable to the environment of other low-altitude areas.

Description

Technical Field

[0001] The invention relates to the field of high-voltage power transmission and distribution, and in particular to an electrical control box and an SVG unit structure that can adapt to high-altitude environments. Background Art

[0002] SVG is a device used for reactive power compensation. In recent decades, it has been widely used in the electric power industry at home and abroad. High-altitude areas, such as Tibet and Qinghai in my country, are usually rich in wind energy, solar energy, hydropower, geothermal energy and other resources. SVG is usually used in the process of converting these energies into electrical energy through power generation equipment and transmitting them to other areas through the power transmission and distribution system.

[0003] High altitude areas have unique geographical and climatic characteristics, which provide a new application environment for SVG. At the same time, they also bring new challenges to SVG designers, which are mainly manifested in the following aspects:

[0004] First: High-altitude areas usually have a large temperature difference between day and night, which may cause a large degree of condensation. At the same time, there is a high possibility of strong wind, sand, dust, salt fog, ice and snow in the area, which puts forward new requirements for our protection level. How to improve its protection level while taking into account heat dissipation is a new challenge facing designers;

[0005] Second: The air is thin in high altitude areas, and the insulation performance of the air will be reduced. Usually, the gap between charged parts or between charged parts and the casing is increased to ensure the insulation performance; however, considering the manufacturing cost, transportation cost, and transportation convenience of industrial products, we are required to increase power density and improve space utilization. How to strike a balance between the two is a major challenge facing designers.

[0006] Third: High altitude areas are sparsely populated and have thin oxygen. At the same time, SVG is likely to be used far away from towns and villages, which makes it very difficult to maintain SVG in this area. Currently, SVGs from various manufacturers generally have more wire harnesses and more connectors. The increase in their number will increase potential failure points and reduce the reliability of the equipment. How to reduce the number of connectors through scientific and reasonable solution design, and achieve less or even no wire harnesses to improve the long-term reliability of the equipment is another major challenge faced by the design. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide an SVG unit structure that can adapt to the special environment of high altitude and operate stably and reliably for a long time.

[0008] The present invention is achieved through the following technical solutions:

[0009] An electrical control box, characterized in that:

[0010] It includes an electrically insulating box body, and also includes one or more of a board, an AC busbar assembly, and a DC busbar assembly;

[0011] The boards are arranged in the box body, including one or more of a driving board, a monitoring board and a power board, and the boards are connected by pins and / or connectors;

[0012] The AC busbar assembly and the DC busbar assembly are installed at the lower part of the box body. One end of the AC busbar and the DC busbar is located outside the box body, and the other end extends out of the box body. The extended length is greater than the length inside the box. An insulating baffle is provided between the DC busbars.

[0013] The most sensitive and fault-prone live boards and other devices are sealed in an insulated electrical control box. The box shell plays a role in waterproofing, dustproofing, insulation and sealing, thereby improving the protection level of the product to adapt to the harsh natural environment in high-altitude areas; the electrical connections between boards are pin-type and / or connector-type connections to reduce the use of connecting harnesses, thereby ensuring the long-term reliability of the equipment; the structure inside the box is compact, and the boards are stacked in the box body, with high space utilization, thereby ensuring a higher power density of the final product.

[0014] Furthermore, all boards and busbars can be installed in multiple independent electrical control boxes, or in an integrated electrical control box. A preferred integrated electrical control box and internal installation structure is: the box body includes a top cover, a middle frame, a middle partition and a box bottom that are stacked up and down and fixed as one; the top cover can be detachably installed on the middle frame, the middle frame can be detachably installed on the box bottom, and the middle partition can be detachably installed in the top opening of the box bottom; the power board can be detachably installed on the middle frame, and the drive board can be detachably installed on the middle partition; the monitoring board is connected to the drive board in a pin-type manner, and the monitoring board and the power board are connected in a connector-type manner; the AC busbar assembly and the DC busbar assembly are installed on both sides of the box bottom. Each board and busbar are installed and fixed in the box body layer by layer through the middle frame and the middle partition in the box, which is convenient for the disassembly and maintenance of the board and busbar, and is conducive to the electrical connection between the boards, and sufficient heat dissipation and installation space can be reserved between the board and the busbar.

[0015] Furthermore, in order to prevent water vapor from penetrating into the box body along the mating surfaces between the various layers of the box body structure, sealing grooves are provided on the mating surfaces between the AC busbar assembly and the DC busbar assembly and the box bottom, between the top cover and the middle frame, and between the middle frame and the box bottom, and the sealing grooves are filled with sealant. The sealing grooves can be used in a single circle or in multiple circles to form a labyrinth-like sealing structure.

[0016] Furthermore, the mating surfaces are provided with sealing flanges, the raised sealing flange on one mating surface is located in the recessed sealing groove on the other mating surface, forming a "U"-shaped sealing groove. The sealing groove can be used in a single circle or in multiple circles to form a labyrinth-like sealing structure.

[0017] Furthermore, the detachable installation includes positioning by positioning posts and detachable installation and fixing by bolts, buckles, springs and other similar parts. Positioning by positioning posts can achieve fast and accurate positioning between each board and each layer of the box body, avoiding damage to components due to alignment problems. Bolts, buckles, springs or other similar installation structures can conveniently assemble and fix the boards and each layer of the box body into one, and can also be easily disassembled when needed.

[0018] Furthermore, the top cover is provided with a waterproof breathable valve, which prevents condensation while ensuring that the air pressure inside and outside the control box is the same; the optical fiber inlet of the middle frame is covered with an optical fiber protective sleeve, such as an elastic rubber sleeve, a silicone sleeve, etc., which can protect the optical fiber while preventing water vapor from entering the box body through the opening.

[0019] An SVG unit structure, characterized by comprising any electrical control box as described above.

[0020] Furthermore, the SVG unit structure also includes a power component; the power component includes an IGBT and a heat sink that are stacked and fixed as one, the gate plate is welded and fixed to the pin on the top of the IGBT, the substrate and the heat sink are integrally formed, and the heat sink is located at the bottom of the substrate; the bottom of the box body is provided with an opening covering the outside of the gate plate and the IGBT, and the driver board and the gate plate are connected by pins; the AC busbar and the DC busbar are located at one end of the box body and can be detachably fixed on the IGBT output positive pole and the IGBT output negative pole; a sealing groove is provided on the mating surface between the box body and the heat sink, and the sealing groove is filled with sealant. The bottom of the box body wraps the gate plate and the IGBT inside to protect them. The opening at the bottom of the box body facilitates the pin to pass through and the connection between the copper busbar and the IGBT, and is also conducive to the heat dissipation upward on part of the gate plate and the IGBT. The sealing groove and the sealant therein completely seal the mating surface between the box body and the heat sink to prevent water vapor and the like from penetrating.

[0021] Furthermore, the bottom of the electrical control box is an insulating and heat-insulating plastic box to achieve the purpose of high temperature resistance. At the same time, due to the low thermal conductivity of the material, the heat transferred from the power component to the control box body can be minimized; the other box body parts above the bottom of the box are insulating and heat-conductive plastic box bodies, and a number of holes are arranged on the middle partition and the top surface of the middle frame, so that the heat from the lower part of the box body can be conducted upward through the holes, and heat exchange occurs with the air through the heat-conductive plastic shell; the bottom of the electrical control box body is provided with a concave ridge that is separated from the top of the power component to reduce the contact between the box body and the power component, thereby minimizing the heat transfer of the power component to the control box.

[0022] Furthermore, the SVG unit structure also includes a capacitor compartment assembly, a laminated busbar, an air duct assembly and a busbar busbar; the capacitor compartment assembly, the laminated busbar and the electrical control box are arranged in parallel; the air duct assembly is arranged at both ends of the radiator; the AC busbar and the DC busbar are respectively electrically connected to their respective busbar busbars in a contact manner. The layout structure is compact, which further ensures the power density of the product and improves the space utilization rate.

[0023] The beneficial effects of the present invention are:

[0024] 1. The most sensitive and fault-prone live boards and other devices are sealed in an insulated electrical control box. Through a certain structural design, it reaches the IP65 protection level. At the same time, a waterproof and breathable breathing valve is installed to prevent condensation while ensuring the same air pressure inside and outside the control box.

[0025] 2. The thermal conductivity of different parts of the electrical control box varies greatly. Through the hollow structure design, a heat insulation bottom is formed, and a heat conduction channel from bottom to top and outward is formed in the box, so that the box can take into account the functions of heat dissipation and heat insulation;

[0026] 3. The electrical control box is equipped with insulating baffle structures inside and outside the box, which is used to strengthen the insulation between the copper bars of the DC busbar assembly, and meet the insulation requirements of places with thin air without increasing the busbar spacing;

[0027] 4. The connection between boards adopts pin-type and / or connector-type connection, which greatly reduces the number of wire harnesses used, improves the reliability of the equipment, and at the same time provides the possibility for mass automated production;

[0028] Through the above series of structural improvements to the unit, it has the ability to adapt to the harsh environment of high-altitude areas, and at the same time, it also has general adaptability to the environment of other low-altitude areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic diagram of the three-dimensional structure of the electrical control box

[0030] Figure 2 , Figure 3 They are Figure 1 Front view and three-dimensional exploded view

[0031] Figure 4 , Figure 5 The front view and top view of the box bottom are

[0032] Figure 6 A three-dimensional schematic diagram of a DC busbar assembly

[0033] Figure 7 Schematic diagram of the installation structure of the DC busbar assembly and the box bottom

[0034] Figure 8 Schematic diagram of the installation structure of the middle frame, middle partition and box bottom

[0035] Fig. 9 Schematic diagram of the matching structure of optical fiber and optical fiber sheath

[0036] Fig.10 A three-dimensional schematic diagram of the installation structure of the boards and power components inside the electrical control box

[0037] Fig.11 for Fig.10 Left view

[0038] Fig.12 A three-dimensional schematic diagram of the installation structure of the base frame, DC busbar components and power components

[0039] Fig.13 A three-dimensional structural diagram of an SVG unit structure

[0040] Figures 1 to 13 In the figure: 1 is a capacitor compartment assembly, 2 is a laminated busbar, 3 is an electrical control box, 301 is a box bottom, 302 is a middle partition, 303 is a drive board, 304 is a monitoring board, 305 is a middle frame, 306 is an optical fiber cable sheath, 307 is a power board, 308 is a top cover, 309 is a waterproof breathable valve, 310 is a board burning port, 311 is an AC busbar assembly, 312 is a DC busbar assembly, 3121 is a DC busbar, 3122 is a DC busbar seat, 313 is an insulating baffle, 314 is a sealing groove, 315 is a sealing flange, 316 is a raised portion, 317 is a positioning column, 318 is a buckle, 4 is a power component, 401 is a gate plate, 402 is an IGBT, 4021 is an IGBT output positive electrode, 4022 is an IGBT output negative electrode, 403 is a heat sink, 5 is an air duct assembly, and 6 is a busbar. DETAILED DESCRIPTION

[0041] The present invention will be further described below in conjunction with the accompanying drawings.

[0042] Example 1

[0043] like Figures 1 to 3 The electrical control box 3 shown includes an electrically insulating box body and boards and cards arranged in the box body, an AC busbar assembly 311 and a DC busbar assembly 312; the box body includes a top cover 308, a middle frame 305, a middle partition 302 and a box bottom 301 which are stacked up and down and fixed as a whole in a detachable manner; the boards and cards include a driving board 303, a monitoring board 304 and a power board 307, and the boards and cards are connected by pin-type and / or connector-type connections.

[0044] Specifically, the top cover 308 is installed on the middle frame 305 by bolts, the middle frame 305 is positioned by the positioning columns 317 on the box bottom 301, and then installed on the box bottom 301 by bolts, and the middle partition 302 is installed in the top opening of the box bottom 301 by bolts; the monitoring board 304 and the power board 307 are positioned by the positioning columns 317 on the middle frame 305, and then installed on the upper and lower sides of the middle frame 305 respectively by buckles; the driving board 303 is positioned by the positioning columns 317 on the middle partition 302, and then installed on the middle partition 302 by buckles; the monitoring board 304 is pin-connected to the driving board 303, and the pin socket on the monitoring board 304 corresponds one-to-one to the pin on the driving board 303; the monitoring board 304 and the power board 307 are connected in a connector-type manner.

[0045] The AC busbar assembly 311 and the DC busbar assembly 312 are installed on both sides of the box bottom 301. The DC busbar assembly 312 includes an insulated DC busbar seat 3122 and a conductive DC busbar 3121. The AC busbar assembly 311 includes an insulated AC busbar seat and an AC busbar. One end of the AC busbar and the DC busbar 3121 is located outside the box body, and the other end extends out of the box body, and the extension length is greater than the length inside the box; an insulating baffle 313 is provided between the DC busbars 3121; Figure 5 , Figure 7 As shown, the insulating baffle 313 located in the box body is integrally formed with the box bottom 301 , and the insulating baffle 313 located in the box body is integrally formed with the DC busbar seat 3122 .

[0046] The middle frame 305 is provided with many ventilation holes, and the middle partition plate 302 is in a grid frame shape to form a heat dissipation channel from bottom to top and outward.

[0047] To prevent external water vapor from entering the box body, a waterproof breathable valve 309 is provided on the top cover 308; an optical fiber protection sleeve 306 is set on the optical fiber entrance of the middle frame 305, and the optical fiber protection sleeve 306 cooperates with the access optical fiber of the monitoring board 304 as shown in the following figure. Fig. 9 A sealing groove 314 is provided on the mating surface between the AC busbar assembly 311 and the box bottom 301, and between the DC busbar assembly 312 and the box bottom 301. The sealing groove 314 is filled with sealant. This sealing structure is shown in FIG. Figure 7A sealing flange 315 is also provided on the mating surfaces between the top cover 308 and the middle frame 305, and between the middle frame 305 and the bottom 301. The raised sealing flange 315 on one mating surface is located in the recessed sealing groove 314 on the other mating surface, forming a "U"-shaped sealing groove. This sealing structure is as shown in FIG. Figure 8 shown.

[0048] Example 2

[0049] like Figures 10-12 The SVG unit structure shown also includes a power component 4; the power component 4 includes an IGBT402 and a heat sink 403 which are stacked and fixed as a whole, the gate plate 401 is welded and fixed to the pins on the top of the IGBT402, the substrate and the heat sink 403 are integrally formed, and the heat sink fins are located at the bottom of the substrate.

[0050] The box bottom 301 is positioned with the heat sink 403 through the positioning column 317 and fixed to the base plate of the heat sink 403 by bolts; the box bottom 301 is provided with an opening covering the outside of the gate plate 401 and the IGBT 402, the drive board 303 and the gate plate 401 are connected by pins, and the pin holder on the drive board 303 corresponds to the pin on the gate plate 401 one by one; the AC busbar and the DC busbar 3121 are located at one end of the box body and are detachably fixed on the IGBT output positive electrode 4021 and the IGBT output negative electrode 4022, and the insulating baffle 313 located in the box body also plays a role in strengthening the insulation of the DC busbar 3121 and the connected IGBT output positive electrode 4021 and the IGBT output negative electrode 4022, such as Figure 7 , Fig.12 As shown; a sealing groove 314 is provided on the mating surface between the box body and the radiator 403, and the sealing groove 314 is filled with sealant.

[0051] The positioning post 317 at the bottom of the middle partition 302 passes through the opening of the box bottom 301 and is inserted into the opening on the gate plate 401 to position the middle partition 302 .

[0052] The bottom 301 of the box is an insulating and heat-insulating plastic box body, and the top cover 308, the middle frame 305, and the middle partition 302 are insulating and heat-conducting plastic box bodies; Figure 4 , Figure 5 As shown, a concave protrusion 316 is provided at the bottom of the electrical control box body and is separated from the top of the power component 4.

[0053] Example 3

[0054] like Fig.13The SVG unit structure shown also includes a capacitor bin assembly 1, a laminated busbar 2, an air duct assembly 5 and a busbar 6; the capacitor bin assembly 1, the laminated busbar 2 and the electrical control box 3 are arranged in parallel; the air duct assembly 5 is configured at both ends of the radiator 403; the AC busbar and the DC busbar 3121 are respectively electrically connected to their respective busbars 5 in a contact manner.

[0055] like Figures 1 to 3 The electrical control box solution shown in the figure seals the sensitive components such as the boards used in the traditional SVG in the box body, and the box body is made of plastic material. Since plastic has insulating properties, this solves the problem of insufficient insulation gap and creepage distance between the conductors (such as AC busbar assembly 311, DC busbar assembly 312, drive board 303, monitoring board 304 and power board 307, etc.) and the housing of the electrical control box under rarefied air conditions.

[0056] like Figure 2 The electrical control box shown includes the following parts: a box bottom 301, a middle partition 302, a drive board 303, a monitoring board 304, a middle frame 305, an optical fiber sheath 306, a power board 307, a top cover 308, a waterproof breathable valve 309, a board burning port 310, an AC busbar assembly 311, and a DC busbar assembly 312.

[0057] The bottom of the box 301 is at the bottom, in the shape of a hollow frame, with openings at the bottom corresponding to the gate plate 401 and the IGBT 402, and a raised portion 316 between the openings; the bottom of the box 301 is positioned with the power component 4 through the positioning column 317 at the bottom thereof, and is fixed to the base plate of the radiator 4 by bolts; the drive board 303 is positioned through the positioning column 317 on the middle partition 302, and then fixed to the middle partition 302 by the buckle 318; the middle partition 302 is positioned with the gate plate 401 through the positioning column 317 at the bottom thereof, and then the middle partition 302 is fixed to the bottom of the box 301 by bolts; The pin sockets on the driving board 303 correspond one-to-one with the pins on the IGBT gate plate 401; the monitoring board 304 and the power board 307 are positioned by the positioning columns 317 on the middle frame 305, and then fixed by the buckles 318 on the middle frame 305; the middle frame 305 is positioned with the box bottom 301 by the positioning columns 317 on the upper part of the box bottom 301, and the pin sockets on the monitoring board 304 correspond one-to-one with the pins on the driving board 303, and then the middle frame 305 is connected to the box bottom 301 by bolts; finally, the top cover 308 is connected to the middle frame 305 by bolts, and the main body of the electrical control box is assembled.

[0058] In this embodiment, in order to achieve the IP65 protection level and take into account the heat dissipation design, the electrical control box 3 has the following special designs:

[0059] First, a groove sealing structure is used, and sealant is added in the groove to achieve the purpose of waterproofing and dustproofing. Figure 7 The sealing is performed in the first method, that is, a sealing groove 314 is provided on the corresponding mating surface, and the sealing groove 314 is filled with sealant; between the bottom 301 and the middle frame 305, and between the middle frame 305 and the top cover 308, a sealing groove 314 is provided. Figure 8 The middle method has two rows of seals, that is, a sealing groove 314 and a sealing flange 315 are respectively provided on the mating surfaces, and the raised sealing flange 315 on one mating surface is located in the recessed sealing groove 314 on the other mating surface to form a "U"-shaped sealing groove, and the sealing groove is filled with sealant.

[0060] Second, the connection between the boards adopts a pin structure or a connector structure, so that there are no other wiring harnesses inside the electrical control box except the two sets of incoming wires of the power board 307, which greatly reduces the number of parts and reduces the potential failure rate.

[0061] Third, due to the structure of the IGBT itself, the distance between the DC output lines is relatively close. In order to enhance the insulation performance, insulating baffles 313 are provided inside and outside the control box bottom 301 (see FIG. Figure 7 , Fig.12 ).

[0062] Fourth, relative to the electrical control box, the temperature of the substrate of the heat sink 4 is closest to the temperature of the IGBT 402 and the gate plate 401, and is considered a heat source. In order to take heat dissipation into consideration, the bottom 301 of the box is raised, and the raised portion 316 is separated from the substrate of the heat sink 4 to reduce contact with the substrate of the heat sink 4, thereby minimizing the heat transfer of the power component 4 to the control box ( Figure 4 , 5 , 12); at the same time, since the copper busbars of the AC busbar and the DC busbar 3121 are at high temperatures during the operation of the SVG, the box bottom 301 is designed to be a long strip with a narrow width to minimize the size of the copper busbar in the control box so that the copper busbar is exposed as much as possible outside the box bottom 301.

[0063] Fifth, in the selection of materials for the electrical control box, the box bottom 301 is made of insulating heat-insulating plastic, such as ABS+PC, to achieve the purpose of high temperature resistance. At the same time, due to the low thermal conductivity of the material, the heat transferred from the power component 4 to the control box body can be minimized; the other components of the electrical control box (top cover 308, middle frame 305 and middle partition 302) are made of insulating heat-conducting plastic, and at the same time, many holes are added to the top surfaces of the middle partition 302 and the middle frame 305, so that the heat in the lower part of the box body (the heat on the AC busbar component 311 and the DC busbar component 312 and part of the heat on the power component 4) can be conducted upward through the holes, and heat exchange occurs with the air through the thermally conductive plastic shell.

[0064] Sixth, in order to achieve the purpose of waterproof and breathable, so that the air pressure inside and outside the electrical control box remains the same, a waterproof and breathable valve 309 is installed on the control box, and external water vapor cannot enter the electrical control box to avoid condensation, but air can flow. At the same time, at the optical fiber outlet and other parts, there are corresponding rubber optical fiber sheaths 306 for protection, which can protect the optical fiber while preventing water vapor from entering the box body through the opening.

[0065] In summary, through the optimized design of the electrical control box and SVG unit structure, this solution has the following characteristics:

[0066] (1) It can adapt to the special environment of high altitude areas, such as strong wind and sand, large temperature difference between day and night, and heavy condensation;

[0067] (2) Able to adapt to the insulation requirements of thin air environments;

[0068] (3) It has high reliability and minimizes failure rate and maintenance frequency.

Claims

1. An SVG unit structure, characterized in that: Including electrical control box (3), The electrical control box (3) comprises an electrically insulating box body, and also comprises a board, one or more of an AC busbar assembly (311) and a DC busbar assembly (312); the board is arranged in the box body, and comprises one or more of a drive board (303), a monitoring board (304) and a power board (307); the board is connected by pin type and / or connector type; The AC busbar assembly (311) and the DC busbar assembly (312) are mounted on the box body, one end of the AC busbar and the DC busbar (3121) are located inside the box body, and the other end extends outside the box body, and the extended length is greater than the length inside the box; an insulating baffle (313) is provided between the DC busbars (3121); The box body comprises a top cover (308), a middle frame (305), a middle partition (302) and a box bottom (301) which are stacked up and down and fixed as one; the top cover (308) is detachably mounted on the middle frame (305), the middle frame (305) is detachably mounted on the box bottom (301), and the middle partition (302) is detachably mounted in a top opening of the box bottom (301); the power board (307) is detachably mounted on the middle frame (305), and the drive board (303) is detachably mounted on the middle partition (302); the monitoring board (304) is pin-connected to the drive board (303), and the monitoring board (304) and the power board (307) are connected in a connector-type manner; the AC busbar assembly (311) and the DC busbar assembly (312) are mounted on both sides of the box bottom (301); The SVG unit structure further includes a power component (4); The power component (4) comprises an IGBT (402) and a heat sink (403) which are stacked and fixed together, the gate plate (401) is welded and fixed to the pin on the top of the IGBT (402), the base plate and the heat sink (403) are integrally formed, and the heat sink is located at the bottom of the base plate; the bottom of the box body is provided with an opening covering the outside of the gate plate (401) and the IGBT (402), and the drive board (303) and the gate plate (401) are connected by pins; the AC busbar and the DC busbar (3121) are located at one end of the box body and are detachably fixed to the IGBT output positive electrode (4021) and the IGBT output negative electrode (4022); a sealing groove (314) is provided on the mating surface between the box body and the heat sink (403), and the sealing groove (314) is filled with sealant; The bottom of the electrical control box is an insulating and heat-insulating plastic box to achieve the purpose of high temperature resistance. At the same time, due to the low thermal conductivity of the material, the heat transferred from the power component to the control box body can be minimized; the other box body parts above the bottom of the box are insulating and heat-conductive plastic boxes, and a number of holes are provided on the middle partition and the top surface of the middle frame, so that the heat from the lower part of the box can be conducted upward through the holes, and heat exchange occurs with the air through the heat-conductive plastic shell; the bottom of the electrical control box is provided with a concave ridge that is separated from the top of the power component to reduce the contact between the box body and the power component, thereby minimizing the heat transferred from the power component to the control box.

2. The SVG unit structure according to claim 1, characterized in that: Sealing grooves (314) are provided on the mating surfaces between the AC busbar assembly (311) and the DC busbar assembly (312) and the box bottom (301), between the top cover (308) and the middle frame (305), and between the middle frame (305) and the box bottom (301), and the sealing grooves (314) are filled with sealant.

3. The SVG unit structure according to claim 2, characterized in that: A sealing flange (315) is also provided on the mating surface. The raised sealing flange (315) on one mating surface is located in a recessed sealing groove (314) on the other mating surface, forming a "U"-shaped sealing groove.

4. The SVG unit structure according to claim 1, characterized in that: The detachable installation includes positioning via a positioning column (317) and detachable installation and fixing via bolts, buckles (318) or spring clips.

5. The SVG unit structure according to claim 1, characterized in that: The top cover (308) is provided with a waterproof and breathable valve (309); and an optical fiber protection sleeve (306) is sleeved on the optical fiber entrance of the middle frame (305).

6. The SVG unit structure according to claim 1, characterized in that: The SVG unit structure further comprises a capacitor bin assembly (1), a laminated busbar (2), an air duct assembly (5) and a busbar (6); The capacitor bin assembly (1), the laminated busbar (2) and the electrical control box (3) are arranged in parallel; The air duct components (5) are arranged at both ends of the radiator (403); The AC busbar and the DC busbar (3121) are respectively electrically connected to their respective busbars (6) in a contact manner.

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