Busbar parallel connection device

Abstract

The application provides a bus parallel connection device and relates to the technical field of electrical cabinets. The bus parallel connection device comprises a bus cabinet, a large rated current bus joint, a small rated current bus joint and a connector. The application effectively solves the problem of matching the size of insulators between different rated current gas-filled cabinets through an integrated variable-diameter connection structure. The connector is provided with plug-in holes with different inner diameters at two ends, thereby realizing the mechanical butt joint of a large current gas-filled cabinet and a small current gas-filled cabinet. The sealing structure adopts a fluorine rubber piece, and the conductive structure is made of graphene / carbon nanotube composite material, so that the contact resistance is stabilized below 10 mu omega, thereby avoiding the problems of increased contact resistance and excessive temperature rise caused by traditional transition cabinets. The gas pressure monitoring and composite heat dissipation system are innovatively integrated, the safety and reliability of the connection part are significantly improved, a temperature sensor with a precision of plus or minus 0.15 DEG C is used, the risks of partial discharge and overheating are effectively prevented, and the overall structure is reduced by more than 60% compared with the traditional transition cabinet.

Description

Technical Field

[0001] This invention relates to the field of electrical cabinet technology, specifically to a busbar paralleling device. Background Technology

[0002] Gas-insulated switchgear (GIS / C-GIS) is medium- and high-voltage electrical equipment using SF6, N2, or a mixture of gases as the insulating medium, primarily used at voltage levels of 35kV and below. Its core components include busbars, circuit breakers, and disconnectors, all integrated within a metal grounded enclosure, employing vacuum or SF6 arc-extinguishing technology. Gas-insulated switchgear achieves compact size (cabinet width can be less than 600mm) and lightweight design through modular design, equipped with a sealed gas chamber (IP67 protection rating) and a laser-welded stainless steel gas box, with an annual gas leakage rate ≤0.1%.

[0003] In the design of gas-insulated switchgear, there is a direct relationship between rated current and structural dimensions: High-current gas-insulated switchgear: Gas-insulated switchgear with a rated current ≥2000A typically has a busbar disc insulator diameter ≥120mm and a flange outer diameter ≥120mm to meet higher insulation and heat dissipation requirements; Low-current gas-insulated switchgear: Gas-insulated switchgear with a rated current ≤630A typically has a busbar disc insulator diameter ≤80mm and a flange outer diameter ≤80mm, resulting in a more compact structure. This difference in dimensions stems from technical specifications: larger currents require larger insulator sizes to ensure sufficient creepage distance and mechanical strength, while also requiring a larger heat dissipation area to cope with higher thermal loads.

[0004] When gas-insulated switchgear with different rated currents needs to be connected on the same busbar, the following technical challenges are mainly faced:

[0005] Insulator size mismatch: The outer diameter of the insulator flange of a high-current gas-filled switchgear (e.g., 120mm) cannot be directly connected to that of a low-current gas-filled switchgear (e.g., 80mm). The size difference prevents the formation of an effective sealing surface, which may cause gas leakage.

[0006] Electrical performance issues: Insulators of different sizes can cause uneven electric field distribution, potentially leading to partial discharge. Increased contact resistance at connections can cause excessive temperature rise (potentially exceeding the 65K limit).

[0007] Insufficient mechanical strength: The mechanical strength of the reducing joint may not meet the impact requirements of a short-circuit current (e.g., 31.5kA / 4s). Under vibration, the connector is prone to loosening, affecting long-term reliability.

[0008] Currently, the industry is trying to solve the above problems by using intermediate transition cabinets. However, intermediate transition cabinets occupy a lot of space and reduce system reliability. They have failed to fundamentally solve the problem of parallel connection caused by the difference in insulator size between gas-filled cabinets with different rated currents. Therefore, it is necessary to develop new technical solutions to achieve reliable and economical busbar parallel connection. Summary of the Invention

[0009] To address the shortcomings of existing technologies, this invention provides a busbar paralleling device that solves the problems existing in existing busbar paralleling devices.

[0010] To achieve the above objectives, the present invention provides the following technical solution: a busbar paralleling device, comprising a busbar cabinet, a high-rated-current busbar connector, a low-rated-current busbar connector, and a connector. The connector is columnar, with a first limiting ring on its outer circumferential wall near its right end and a second limiting ring on its outer circumferential wall near its left end. A first flange and a second flange are fixedly connected to the outer wall of the connector on opposite sides of the first and second limiting rings, respectively. The right end of the connector has a first insertion hole for connecting to the high-rated-current busbar connector, and the left end of the connector has a second insertion hole for connecting to the low-rated-current busbar connector. Both the first and second insertion holes have sealing structures on their inner walls. The connector is equipped with a conductive structure to improve contact tightness and enhance conductivity. A connecting hole is provided on the inner wall of the connector, between the first and second insertion holes, to allow passage through both holes. A pipe joint is provided on the upper wall of the connector, and a regulating valve is installed on the pipe joint. The end of the pipe joint facing the connector communicates with the interior of the connecting hole. The end of the pipe joint away from the connector is connected to the air chamber of the busbar cabinet via a metal corrugated pipe. A pressure detection structure is provided on the front wall of the connector to detect the air pressure inside the connecting hole. Two sets of heat dissipation sleeves are provided on the upper wall of the connector, between the first and second limiting rings, with the two sets of heat dissipation sleeves located on the left and right sides of the pipe joint, respectively. A temperature detection structure is provided on the upper wall of the connector, between the opposite sides of the two sets of heat dissipation sleeves, to detect the connector temperature.

[0011] The first flange and the second flange are respectively fastened with bolts (torque 25±2N·m) to achieve air chamber sealing. The first limit ring and the second limit ring are used to fix the first flange and the second flange respectively. Different sizes of the first flange and the second flange can be selected according to the size of the busbar disc insulator.

[0012] The metal bellows can compensate for the thermal expansion and contraction of the busbar (axial displacement ≥10mm), and at the same time maintain the pressure balance of the air chamber through the pipe joint 9 to avoid sealing failure due to pressure difference.

[0013] Preferably, the heat dissipation sleeve is composed of a first heat dissipation layer, a second heat dissipation layer and a third heat dissipation layer that are fixedly connected from the inside to the outside. The first heat dissipation layer and the third heat dissipation layer are both aluminum alloy rings. The outer wall of the third heat dissipation layer is provided with multiple sets of protruding ribs for increasing the surface area. The multiple sets of protruding ribs are evenly distributed in a circle with the axis of the third heat dissipation layer as the center. The protrusion height of the multiple sets of protruding ribs is 2~3mm, and the distance between two adjacent sets of protruding ribs is 5~8mm.

[0014] Preferably, the inner wall of the first heat dissipation layer is provided with multiple sets of grooves, and the multiple sets of grooves are evenly distributed in a circle with the axis of the first heat dissipation layer as the center. A TEC module is fixedly connected to the inner wall of each set of grooves. The side of the TEC module facing the axis of the first heat dissipation layer abuts against the outer wall of the connector. The TEC module and the outer wall of the connector are connected by thermally conductive silicone.

[0015] The aluminum alloy base (thermal conductivity ≥200W / m·K) combined with the raised ridge design increases the heat dissipation area by more than 35%, which can effectively conduct heat inside the connector; the TEC module actively dissipates heat through the Peltier effect, and with the thermal conductive silicone (thermal conductivity ≥2.5W / m·K), the hot spot temperature of the connector can be reduced by 8~10℃;

[0016] Preferably, the second heat dissipation layer consists of a shell and a PCM phase change paraffin filling layer filled inside the shell. The shell is a copper-graphene alloy, the PCM phase change paraffin filling layer has a filling density of 85%~90%, and the paraffin phase change range of the PCM phase change paraffin filling layer is 45~65℃.

[0017] When the temperature exceeds 45℃, paraffin undergoes a phase change and absorbs heat (latent heat ≥180kJ / kg). The copper-graphene shell can accelerate heat diffusion, keeping the connector temperature fluctuation range within ±3℃.

[0018] Preferably, the sealing structure includes two sets of sealing grooves and two sets of sealing elements. The two sets of sealing grooves are respectively disposed on the inner sidewalls of the first insertion hole and the second insertion hole. The two sets of sealing elements are respectively disposed on the inner sidewall of one set of sealing grooves. The sealing elements have a rectangular cross-section and are made of fluororubber with a Shore hardness of 70±5.

[0019] Fluororubber seals form a continuous sealing surface within a compression range of 20-30%. Combined with the clamping force of the first flange 4, the annual leakage rate of the gas chamber can be controlled to ≤0.1%, meeting the IP67 protection level requirements.

[0020] Preferably, the conductive structure includes two sets of flexible conductive layers, which are respectively fixedly connected to the inner sidewalls of the first and second insertion holes. Both the first and second insertion holes have annular grooves on their inner sidewalls. The two sets of flexible conductive layers are respectively disposed on the inner sidewalls of one set of annular grooves. The flexible conductive layers are graphene / carbon nanotube composite materials. The inner wall of the set of flexible conductive layers located in the first insertion hole protrudes 1-2 mm from the inner wall of the first insertion hole, and the inner wall of the set of flexible conductive layers located in the second insertion hole protrudes 1-2 mm from the inner wall of the second insertion hole.

[0021] The elastic deformation characteristics of the flexible conductive layer can compensate for the busbar tolerance, and the outstanding design makes the contact pressure ≥0.6MPa. Combined with the low resistance characteristics of graphene material (contact resistance ≤10μΩ), the temperature rise is reduced by more than 40% compared with traditional copper contact surfaces.

[0022] Preferably, the air pressure detection structure is an air pressure gauge, which is threadedly connected to the front wall of the connector, and the air pressure gauge is in communication with the interior of the connecting hole.

[0023] The pressure gauge can display the air chamber pressure in real time (range 0~1.6MPa). With the help of raw rubber tape sealing, leakage of the detection interface can be prevented. When the pressure is lower than 0.3MPa, air needs to be added in time.

[0024] Preferably, the temperature detection structure includes two sets of temperature sensors, both sets of temperature sensors are fixedly connected to the upper wall of the connector, and the two sets of temperature sensors are respectively close to a heat sink. The temperature sensors are PT100 platinum resistance sensors of model WZP-230, and the temperature sensor accuracy is ±0.15℃.

[0025] With the above structure, the high-precision temperature sensor can monitor the surface temperature of the connector in real time (range -50℃~200℃), and with the heat dissipation system, the temperature rise can be controlled below the limit of 65K.

[0026] Preferably, the connector comprises a body and an insulating layer disposed on the outer wall of the body, the insulating layer comprising a silicone rubber insulating layer disposed on the outer wall of the body and a polyimide wear-resistant layer disposed on the outer wall of the silicone rubber insulating layer.

[0027] The silicone rubber insulation layer provides excellent dielectric properties (power frequency withstand voltage ≥95kV), and the polyimide wear-resistant layer can withstand mechanical wear during busbar insertion and removal. The overall insulation performance meets the requirements of GB / T 3906-2020 standard.

[0028] Preferably, the lower wall of the connector is provided with a grounding cable and a threaded hole, which does not communicate with the interior of the connecting hole. A fixing bolt is threaded to the inner side wall of the threaded hole, and the grounding cable is fixedly connected to the connector through the fixing bolt.

[0029] With the above structure, the grounding cable has a cross-sectional area of ​​≥35mm² and a grounding resistance of ≤0.1Ω, which can effectively discharge fault current (≥31.5kA / 4s) and meet the requirements of IEC 62271-200 standard.

[0030] This invention provides a busbar paralleling device. It has the following advantages:

[0031] 1. Compared with existing technologies, this busbar paralleling device effectively solves the problem of insulator size matching between gas-insulated switchgear with different rated currents through an integrated variable diameter connection structure. Its columnar connector has insertion holes of different inner diameters at both ends. Through the coordinated positioning of the limiting ring and flange, mechanical docking of high-current gas-insulated switchgear (≥2000A) and low-current gas-insulated switchgear (≤630A) is achieved. The sealing structure uses fluororubber parts with a Shore hardness of 70±5, ensuring an annual gas chamber leakage rate of ≤0.1% within a 20-30% compression range. Simultaneously, the conductive structure uses graphene / carbon nanotube composite materials to stabilize the contact resistance below 10μΩ, avoiding the problems of increased contact resistance and excessive temperature rise caused by traditional transition switchgear.

[0032] 2. Compared with existing technologies, this busbar paralleling device innovatively integrates air pressure monitoring and a composite heat dissipation system, significantly improving the safety and reliability of the connection parts. The combination design of pipe joints and metal bellows enables real-time monitoring of air chamber pressure, while the three-stage heat dissipation structure (aluminum alloy substrate + TEC module + PCM phase change layer) can control the connector temperature within the 45-65℃ phase change range. Combined with a temperature sensor with an accuracy of ±0.15℃, it effectively prevents the risk of partial discharge and overheating. Its mechanical strength meets the requirements of 31.5kA / 4s short-circuit current impact, and the overall structure reduces the volume by more than 60% compared with traditional transition cabinets. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of the present invention;

[0034] Figure 2 For the present invention Figure 1 A magnified view of a section at point A in the middle;

[0035] Figure 3 This is a schematic diagram of the overall structure of the present invention;

[0036] Figure 4 This is a schematic diagram of the connector structure of the present invention;

[0037] Figure 5 This is a partial cross-sectional view of the internal structure of the connector of the present invention;

[0038] Figure 6 For the present invention Figure 5 A magnified view of a section at point B in the middle;

[0039] Figure 7 For the present invention Figure 5 A magnified view of a section at point C;

[0040] Figure 8 This is a partial cross-sectional view of the internal structure of the heat sink sleeve of the present invention.

[0041] The components are as follows: 1. Connector; 101. Body; 102. Insulating layer; 2. First limiting ring; 3. Second limiting ring; 4. First flange; 5. Second flange; 6. First insertion hole; 7. Second insertion hole; 8. Seal; 9. Pipe joint; 10. Regulating valve; 11. Pressure gauge; 12. Grounding cable; 13. Temperature sensor; 14. First heat dissipation layer; 15. Second heat dissipation layer; 1501. Housing; 1502. PCM phase change paraffin filling layer; 16. Third heat dissipation layer; 17. Raised ridge; 18. Sealing groove; 19. Flexible conductive layer; 20. TEC module; 21. Connecting hole. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] Example:

[0044] like Figures 1 to 8 As shown, an embodiment of the present invention provides a busbar paralleling device, including a busbar cabinet, a high rated current busbar connector, a low rated current busbar connector, and a connector 1;

[0045] To ensure reliable parallel connection of gas-filled cabinets with different rated currents, connector 1 is columnar. Connector 1 consists of a main body 101 and an insulating layer 102 disposed on the outer wall of the main body 101. The insulating layer 102 consists of a silicone rubber insulating layer disposed on the outer wall of the main body 101 and a polyimide wear-resistant layer disposed on the outer wall of the silicone rubber insulating layer.

[0046] The silicone rubber insulation layer provides excellent dielectric properties (power frequency withstand voltage ≥95kV), and the polyimide wear-resistant layer can withstand mechanical wear during busbar insertion and removal. The overall insulation performance meets the requirements of GB / T 3906-2020 standard.

[0047] To achieve mechanical connection between the high-current bus and the low-current bus, a first limiting ring 2 is provided on the outer wall of connector 1 near the right end, and a second limiting ring 3 is provided on the outer wall of connector 1 near the left end. A first flange 4 and a second flange 5 are fixedly connected to the outer wall of connector 1 on the side opposite to the first limiting ring 2 and the second limiting ring 3, respectively. A first insertion hole 6 for connecting with the high-rated current bus connector is provided on the right end of connector 1, and a second insertion hole 7 for connecting with the low-rated current bus connector is provided on the left end of connector 1.

[0048] The first flange 4 and the second flange 5 are respectively fastened with bolts (torque 25±2N·m) to achieve air chamber sealing. The first limiting ring 2 and the second limiting ring 3 are respectively used to fix the first flange 4 and the second flange 5. The first flange 4 and the second flange 5 of different sizes can be selected according to the size of the busbar disc insulator.

[0049] To prevent gas leakage, the inner walls of the first insertion hole 6 and the second insertion hole 7 are provided with sealing structures. The sealing structures include two sets of sealing grooves 18 and two sets of sealing elements 8. The two sets of sealing grooves 18 are respectively provided on the inner walls of the first insertion hole 6 and the second insertion hole 7. The two sets of sealing elements 8 are respectively provided on the inner walls of one set of sealing grooves 18. The sealing element 8 has a rectangular cross section and is made of fluororubber with a Shore hardness of 70±5.

[0050] Fluororubber seals form a continuous sealing surface within a compression range of 20-30%. Combined with the clamping force of the first flange 4, the annual leakage rate of the gas chamber can be controlled to ≤0.1%, meeting the IP67 protection level requirements.

[0051] To reduce contact resistance, conductive structures are provided on the inner walls of the first insertion hole 6 and the second insertion hole 7 to improve the contact tightness and thus enhance conductivity. The conductive structures include two sets of flexible conductive layers 19, which are fixedly connected to the inner walls of the first insertion hole 6 and the second insertion hole 7, respectively. The inner walls of the first insertion hole 6 and the second insertion hole 7 are provided with annular grooves. The two sets of flexible conductive layers 19 are respectively disposed on the inner walls of one set of annular grooves. The flexible conductive layers 19 are graphene / carbon nanotube composite materials. The inner wall of the set of flexible conductive layers 19 located in the first insertion hole 6 protrudes 1~2mm from the inner wall of the first insertion hole 6, and the inner wall of the set of flexible conductive layers 19 located in the second insertion hole 7 protrudes 1~2mm from the inner wall of the second insertion hole 7.

[0052] The elastic deformation characteristics of the flexible conductive layer 19 can compensate for the busbar tolerance. The outstanding design ensures a contact pressure ≥0.6MPa. Combined with the low resistance characteristics of graphene material (contact resistance ≤10μΩ), the temperature rise is reduced by more than 40% compared with traditional copper contact surfaces.

[0053] In order to achieve pressure equalization in the air chamber, a connecting hole 21 is provided on the inner wall of the connector 1 between the first insertion hole 6 and the second insertion hole 7 for passing through the first insertion hole 6 and the second insertion hole 7. A pipe joint 9 is provided on the upper wall of the connector 1, and a regulating valve 10 is provided on the pipe joint 9. The end of the pipe joint 9 facing the connector 1 is connected to the interior of the connecting hole 21, and the end of the pipe joint 9 away from the connector 1 is connected to the air chamber of the bus cabinet through a metal corrugated pipe.

[0054] The metal bellows can compensate for the thermal expansion and contraction of the busbar (axial displacement ≥10mm), and at the same time maintain the pressure balance of the air chamber through the pipe joint 9 to avoid sealing failure due to pressure difference.

[0055] In order to monitor the air chamber pressure in real time, the front wall of connector 1 is provided with an air pressure detection structure for detecting the air pressure inside the connecting hole 21. The air pressure detection structure is an air pressure gauge 11, which is threaded to the front wall of connector 1 and is in communication with the inside of the connecting hole 21.

[0056] The pressure gauge 11 can display the pressure of the air chamber in real time (range 0~1.6MPa). With the help of raw rubber tape sealing, leakage of the detection interface can be prevented. When the pressure is lower than 0.3MPa, air needs to be replenished in time.

[0057] To improve heat dissipation efficiency, two sets of heat dissipation sleeves are provided on the upper wall of connector 1 and between the first limiting ring 2 and the second limiting ring 3. The two sets of heat dissipation sleeves are located on the left and right sides of the pipe joint 9, respectively. The heat dissipation sleeves are composed of a first heat dissipation layer 14, a second heat dissipation layer 15 and a third heat dissipation layer 16, which are fixedly connected from the inside to the outside. The first heat dissipation layer 14 and the third heat dissipation layer 16 are both aluminum alloy rings. The outer wall of the third heat dissipation layer 16 is provided with multiple sets of protruding ribs 17 to increase the surface area. The multiple sets of protruding ribs 17 are evenly distributed in a circle with the axis of the third heat dissipation layer 16 as the center. The protrusion height of the multiple sets of protruding ribs 17 is 2~3mm, and the distance between two adjacent sets of protruding ribs 17 is 5~8mm.

[0058] The aluminum alloy base (thermal conductivity ≥200W / m·K) combined with the convex ridge 17 design increases the heat dissipation area by more than 35%, which can effectively conduct heat inside the connector 1;

[0059] To enhance active heat dissipation, multiple sets of grooves are provided on the inner wall of the first heat dissipation layer 14. The multiple sets of grooves are evenly distributed in a circle with the axis of the first heat dissipation layer 14 as the center. A TEC module 20 is fixedly connected to the inner wall of each set of grooves. The side of the TEC module 20 facing the axis of the first heat dissipation layer 14 abuts against the outer wall of the connector 1. The TEC module 20 and the outer wall of the connector 1 are connected by thermally conductive silicone.

[0060] The TEC module 20 actively dissipates heat through the Peltier effect, and with the help of thermally conductive silicone (thermal conductivity ≥2.5W / m·K), the hot spot temperature of connector 1 can be reduced by 8~10℃;

[0061] To enhance temperature buffering capacity, the second heat dissipation layer 15 consists of a shell 1501 and a PCM phase change paraffin filling layer 1502 filled inside the shell 1501. The shell 1501 is a copper-graphene alloy, the PCM phase change paraffin filling layer 1502 has a filling density of 85%-90%, and the paraffin phase change range of the PCM phase change paraffin filling layer 1502 is 45-65℃.

[0062] When the temperature exceeds 45℃, paraffin undergoes a phase change and absorbs heat (latent heat ≥180kJ / kg). The copper-graphene shell can accelerate heat diffusion, keeping the temperature fluctuation range of connector 1 within ±3℃.

[0063] In order to accurately monitor the temperature, a temperature detection structure for detecting the temperature of connector 1 is provided on the upper wall of connector 1 and between the two sets of heat sinks on opposite sides. The temperature detection structure includes two sets of temperature sensors 13. Both sets of temperature sensors 13 are fixedly connected to the upper wall of connector 1. The two sets of temperature sensors 13 are close to one set of heat sinks respectively. The temperature sensors 13 are PT100 platinum resistance sensors of model WZP-230, and the accuracy of temperature sensors 13 is ±0.15℃.

[0064] The high-precision temperature sensor 13 can monitor the surface temperature of connector 1 in real time (range -50℃~200℃), and with the heat dissipation system, the temperature rise can be controlled below the limit of 65K.

[0065] To ensure safe grounding, a grounding cable 12 is provided on the lower wall of connector 1. A threaded hole is provided on the lower wall of connector 1. The threaded hole does not pass through the interior of the connecting hole 21. A fixing bolt is threaded to the inner side wall of the threaded hole. The grounding cable 12 is fixedly connected to connector 1 through the fixing bolt.

[0066] The grounding cable has a cross-sectional area of ​​≥35mm² and a grounding resistance of ≤0.1Ω, which can effectively discharge fault current (≥31.5kA / 4s) and meet the requirements of IEC 62271-200 standard.

[0067] Working principle: Connector 1 consists of a body 101 and an insulating layer 102 disposed on the outer wall of the body 101. The insulating layer 102 consists of a silicone rubber insulating layer disposed on the outer wall of the body 101 and a polyimide wear-resistant layer disposed on the outer wall of the silicone rubber insulating layer. The silicone rubber insulating layer provides excellent dielectric properties (power frequency withstand voltage ≥95kV), and the polyimide wear-resistant layer can withstand mechanical wear during busbar insertion and removal. The overall insulation performance meets GB / T standards. According to the 3906-2020 standard, the first flange 4 and the second flange 5 are fastened with bolts (torque 25±2 N·m) to achieve air chamber sealing. The first limiting ring 2 and the second limiting ring 3 are used to fix the first flange 4 and the second flange 5, respectively. Different sizes of the first flange 4 and the second flange 5 can be selected according to the size of the busbar disc insulator. The sealing element 8 has a rectangular cross-section and is made of fluororubber with a Shore hardness of 70±5. The fluororubber sealing element forms a continuous sealing surface within a compression range of 20-30%. Combined with the clamping force of the first flange 4, the annual leakage rate of the air chamber can be controlled to ≤0.1%, meeting the IP67 protection level requirements. The inner walls of the first insertion hole 6 and the second insertion hole 7 are provided with annular grooves. Two sets of flexible conductive layers 19 are respectively set on the inner wall of one set of annular grooves. The flexible conductive layer 19 is a graphene / carbon nanotube composite material. The set of flexible conductive layers 19 located on the inner wall of the first insertion hole 6 is... The inner wall of one of the two sets of flexible conductive layers 19 protrudes 1-2mm from the inner wall of the first insertion hole 6, and the inner wall of the set located in the second insertion hole 7 protrudes 1-2mm from the inner wall of the second insertion hole 7. The elastic deformation characteristics of the flexible conductive layer 19 can compensate for the busbar tolerance. The protruding design ensures a contact pressure ≥0.6MPa. Combined with the low resistance characteristics of graphene material (contact resistance ≤10μΩ), the temperature rise is reduced by more than 40% compared with the traditional copper contact surface. The end of the pipe joint 9 facing the connector 1 is connected to the interior of the connecting hole 21. The end of the pipe joint 9 away from the connector 1 is connected to the air chamber of the busbar cabinet through a metal bellows. The metal bellows can compensate for the thermal expansion and contraction of the busbar (axial displacement ≥10mm). At the same time, the pipe joint 9 maintains the pressure balance of the air chamber and avoids sealing failure due to pressure difference. The pressure gauge 11 can display the air chamber pressure in real time (range 0~1.6MPa). Combined with the Teflon tape seal, it can prevent leakage of the detection interface. When the pressure is below 0.When the pressure is 3MPa, timely air replenishment is required. The heat dissipation sleeve is composed of a first heat dissipation layer 14, a second heat dissipation layer 15, and a third heat dissipation layer 16, which are fixedly connected from the inside to the outside. The first heat dissipation layer 14 and the third heat dissipation layer 16 are both aluminum alloy rings. The outer wall of the third heat dissipation layer 16 is provided with multiple sets of protruding ribs 17 to increase the surface area. The multiple sets of protruding ribs 17 are evenly distributed in a circle with the axis of the third heat dissipation layer 16 as the center. The protrusion height of the multiple sets of protruding ribs 17 is 2~3mm, and the distance between two adjacent sets of protruding ribs 17 is 5~8mm. The aluminum alloy substrate (thermal conductivity ≥200W / m·K) combined with the raised ridge 17 design increases the heat dissipation area by more than 35%, effectively conducting heat inside connector 1; the TEC module 20 is connected to the outer wall of connector 1 via thermally conductive silicone; the TEC module 20 actively dissipates heat through the Peltier effect, and with the thermally conductive silicone (thermal conductivity ≥2.5W / m·K), the hot spot temperature of connector 1 can be reduced by 8~10℃; the second heat dissipation layer 15 consists of the housing 1501 and the P-type silicone filling the inside of the housing 1501. The PCM phase change paraffin filling layer 1502 is composed of a copper-graphene alloy housing 1501 and a PCM phase change paraffin filling layer 1502 with a filling density of 85%~90%. The paraffin phase change range of the PCM phase change paraffin filling layer 1502 is 45-65℃. When the temperature exceeds 45℃, the paraffin undergoes a phase change and absorbs heat (latent heat ≥180kJ / kg). The copper-graphene housing can accelerate heat dissipation, keeping the temperature fluctuation range of connector 1 within ±3℃. The temperature sensor 13 adopts model W. The ZP-230 uses a PT100 platinum resistance thermometer, with temperature sensor 13 having an accuracy of ±0.15℃. This high-precision temperature sensor 13 can monitor the surface temperature of connector 1 in real time (range -50~200℃), and with the heat dissipation system, the temperature rise can be controlled below the 65K limit. Grounding cable 12 is fixedly connected to connector 1 via fixing bolts. Grounding cable 12 has a cross-sectional area ≥35mm², a grounding resistance ≤0.1Ω, and can effectively discharge fault current (≥31.5kA / 4s), meeting the requirements of IEC 62271-200 standard.

[0068] The integrated variable-diameter connection structure effectively solves the problem of insulator size matching between gas-filled switchgear with different rated currents. Its cylindrical connector has insertion holes of different inner diameters at both ends. Through the coordinated positioning of the limiting ring and flange, mechanical docking of high-current gas-filled switchgear (≥2000A) and low-current gas-filled switchgear (≤630A) is achieved. The sealing structure uses fluororubber parts with a Shore hardness of 70±5, ensuring an annual gas chamber leakage rate of ≤0.1% within a compression range of 20~30%. Simultaneously, the conductive structure uses graphene / carbon nanotube composite materials to stabilize the contact resistance below 10μΩ, avoiding the problems of increased contact resistance and excessive temperature rise caused by traditional transition switchgear.

[0069] The innovative integration of air pressure monitoring and a composite heat dissipation system significantly enhances the safety and reliability of the connection points. The combination design of the pipe joint and metal bellows enables real-time monitoring of the air chamber pressure, while the three-stage heat dissipation structure (aluminum alloy substrate + TEC module + PCM phase change layer) can control the connector temperature within the 45~65℃ phase change range. Combined with a temperature sensor with an accuracy of ±0.15℃, it effectively prevents the risks of partial discharge and overheating. Its mechanical strength meets the requirements of a 31.5kA / 4s short-circuit current impact, and the overall structure reduces the volume by more than 60% compared to traditional transition cabinets.

[0070] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A busbar paralleling device, characterized in that: The device includes a busbar cabinet, a high-rated-current busbar connector, a low-rated-current busbar connector, and a connector (1). The connector (1) is columnar. A first limiting ring (2) is provided on the outer circumferential wall of the connector (1) near the right end. A second limiting ring (3) is provided on the outer circumferential wall of the connector (1) near the left end. A first flange (4) and a second flange (5) are fixedly connected to the outer wall of the connector (1) on the side opposite to the first limiting ring (2) and the second limiting ring (3), respectively. A first insertion hole (6) for connecting with the high-rated-current busbar connector is provided on the right end of the connector (1). A second insertion hole (7) for connecting with the low-rated-current busbar connector is provided on the left end of the connector (1). The inner walls of the first insertion hole (6) and the second insertion hole (7) are both provided with sealing structures. The inner walls of the first insertion hole (6) and the second insertion hole (7) are both provided with conductive structures to improve the contact tightness and thus improve conductivity. The connector (1) has a connecting hole (21) on its inner wall between the first plug hole (6) and the second plug hole (7) for passing through the first plug hole (6) and the second plug hole (7). The connector (1) has a pipe joint (9) on its upper wall. The pipe joint (9) has a regulating valve (10) on it. The end of the pipe joint (9) facing the connector (1) is connected to the inside of the connecting hole (21). The end of the pipe joint (9) away from the connector (1) is connected to the air chamber of the busbar cabinet through a metal corrugated pipe. The front wall of the connector (1) has a pressure detection structure for detecting the air pressure inside the connecting hole (21). The connector (1) has two sets of heat dissipation sleeves on its upper wall between the first limiting ring (2) and the second limiting ring (3). The two sets of heat dissipation sleeves are located on the left and right sides of the pipe joint (9). The connector (1) has a temperature detection structure for detecting the temperature of the connector (1) on its upper wall between the two sets of heat dissipation sleeves. The conductive structure includes two sets of flexible conductive layers (19). The two sets of flexible conductive layers (19) are fixedly connected to the inner sidewalls of the first insertion hole (6) and the second insertion hole (7), respectively. The inner sidewalls of the first insertion hole (6) and the second insertion hole (7) are provided with annular grooves. The two sets of flexible conductive layers (19) are respectively disposed on the inner sidewalls of one set of annular grooves. The flexible conductive layer (19) is a graphene / carbon nanotube composite material. The inner wall of one set of flexible conductive layers (19) located in the first insertion hole (6) protrudes 1~2mm from the inner wall of the first insertion hole (6). The inner wall of one set of flexible conductive layers (19) located in the second insertion hole (7) protrudes 1~2mm from the inner wall of the second insertion hole (7).

2. The busbar paralleling device according to claim 1, characterized in that: The heat dissipation sleeve is composed of a first heat dissipation layer (14), a second heat dissipation layer (15), and a third heat dissipation layer (16) that are fixedly connected from the inside to the outside. The first heat dissipation layer (14) and the third heat dissipation layer (16) are both aluminum alloy rings. The outer wall of the third heat dissipation layer (16) is provided with multiple sets of protruding ribs (17) for increasing the surface area. The multiple sets of protruding ribs (17) are evenly distributed in a circle with the axis of the third heat dissipation layer (16) as the center. The protrusion height of the multiple sets of protruding ribs (17) is 2~3mm, and the distance between two adjacent sets of protruding ribs (17) is 5~8mm.

3. A busbar paralleling device according to claim 2, characterized in that: The inner wall of the first heat dissipation layer (14) is provided with multiple sets of grooves. The multiple sets of grooves are distributed in a circle with the axis of the first heat dissipation layer (14) as the center. Each set of grooves is fixedly connected to a TEC module (20) on its inner wall. The side of the TEC module (20) facing the axis of the first heat dissipation layer (14) abuts against the outer wall of the connector (1). The TEC module (20) and the outer wall of the connector (1) are connected by thermally conductive silicone.

4. A busbar paralleling device according to claim 3, characterized in that: The second heat dissipation layer (15) consists of a shell (1501) and a PCM phase change paraffin filling layer (1502) filled inside the shell (1501). The shell (1501) is a copper-graphene alloy. The PCM phase change paraffin filling layer (1502) has a filling density of 85%~90% and a paraffin phase change range of 45~65℃.

5. A busbar paralleling device according to claim 4, characterized in that: The sealing structure includes two sets of sealing grooves (18) and two sets of sealing elements (8). The two sets of sealing grooves (18) are respectively disposed on the inner sidewalls of the first insertion hole (6) and the second insertion hole (7). The two sets of sealing elements (8) are respectively disposed on the inner sidewalls of one set of sealing grooves (18). The sealing element (8) has a rectangular cross section and is made of fluororubber with a Shore hardness of 70±5.

6. A busbar paralleling device according to claim 5, characterized in that: The air pressure detection structure is an air pressure gauge (11), which is threaded to the front wall of the connector (1) and is connected to the inside of the connecting hole (21).

7. A busbar paralleling device according to claim 6, characterized in that: The temperature detection structure includes two sets of temperature sensors (13). Both sets of temperature sensors (13) are fixedly connected to the upper wall of the connector (1). The two sets of temperature sensors (13) are close to a heat sink. The temperature sensors (13) are PT100 platinum resistance sensors of model WZP-230. The accuracy of the temperature sensors (13) is ±0.15℃.

8. A busbar paralleling device according to claim 7, characterized in that: The connector (1) consists of a body (101) and an insulating layer (102) disposed on the outer wall of the body (101). The insulating layer (102) consists of a silicone rubber insulating layer disposed on the outer wall of the body (101) and a polyimide wear-resistant layer disposed on the outer wall of the silicone rubber insulating layer.

9. A busbar paralleling device according to claim 8, characterized in that: The lower wall of the connector (1) is provided with a grounding cable (12), and the lower wall of the connector (1) is provided with a threaded hole. The threaded hole does not communicate with the interior of the connecting hole (21). The inner side wall of the threaded hole is threaded with a fixing bolt. The grounding cable (12) is fixedly connected to the connector (1) through the fixing bolt.

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