Bus connecting device and combined cabinet structure

Abstract

The utility model relates to the technical field of structural design of power equipment, and particularly provides a bus connecting device and a combined cabinet structure, the bus connecting device comprises a bus used for being connected with outgoing line terminals of two adjacent gas-insulated switchgears, and bus cylinders used for being respectively sleeved outside the outgoing line terminals of the two adjacent gas-insulated switchgears, and the bus cylinders are respectively sleeved outside the outgoing line terminals of the two adjacent gas-insulated switchgears. A current transformer is arranged outside the bus, the current transformer is located between the bus cylinders on the two sides, the two ends of the current transformer and the bus cylinders on the two sides are assembled in an inserted and sealed mode, a measuring coil is poured in the current transformer, the current transformer and the bus are integrally formed through pouring, and the space interval between the current transformer and the bus is eliminated. The current transformer is attached to the bus, and the current transformer does not move in the vertical direction under the condition that vibration is generated during opening and closing of the gas-insulated switchgear, so that the sealing and insulating effects of the current transformer and the plugging and sealing assembly positions of the bus cylinders on the two sides are good, and the leakage of insulating gas is avoided.

Description

Technical Field

[0001] This utility model belongs to the field of power equipment structural design technology, specifically relating to a busbar connection device and a parallel cabinet structure. Background Technology

[0002] With the development of the power industry, gas-insulated switchgear (GES) has been widely used in the power sector due to its high reliability, all-condition operation, and maintenance-free characteristics. GES is filled with insulating media such as SF6 or N2. In practice, it is often necessary to connect adjacent GES via an insulated busbar. Generally, a current transformer is installed on this busbar to monitor the busbar current in real time, thus providing necessary protection for electrical equipment. However, if a current transformer is installed at the connection busbar, it needs to be installed outside the GES casing. This results in a significantly larger outer diameter current transformer, increasing its cost and contradicting the miniaturization design of GES, which is not in line with current technological development trends.

[0003] Based on this, the invention patent application with publication number CN118920284A discloses a busbar connection device and a parallel cabinet structure. The busbar connection device includes a busbar for connecting to the outgoing terminals of two adjacent gas-insulated cabinets, and a busbar cylinder for being sleeved on the outgoing terminals of the gas-insulated cabinets. A current transformer is sleeved outside the busbar. The two ends of the current transformer are sealed and assembled with the two busbar cylinders on both sides. The busbar cylinder and the current transformer form a sealed chamber for filling with insulating gas. The two ends of the current transformer can be sealed and assembled with the two busbar cylinders on both sides respectively, creating an independent sealed chamber. The sealed chamber completely contains the busbar used for parallel cabinets within its internal space. Only the insulating gas needs to be filled in the sealed chamber to provide a reliable and stable insulation environment for the busbar, thereby effectively ensuring the performance and operational reliability of the parallel cabinet product. However, in the aforementioned busbar connection device, the current transformer is merely sleeved outside the busbar and inserted into the sealing cylinders on both sides for sealing assembly. The current transformer is spaced apart from the busbar, and the current transformer is sealed by a sealing ring assembled with the inner wall of the busbar cylinder. Due to the large weight of the current transformer, the lower part of the sealing ring is compressed more than the upper part, resulting in inconsistent compression in the circumferential direction. This leads to uneven sealing and a risk of leakage. Especially when the gas-insulated switchgear vibrates during opening and closing, the current transformer may move vertically, making it easier for the sealing assembly between the current transformer and the busbar cylinders on both sides to fail to seal properly, leading to leakage of insulating gas and poor insulation performance. Utility Model Content

[0004] The purpose of this utility model is to provide a busbar connection device to solve the technical problem in current busbar connection devices where uneven sealing along the circumference of the current transformer due to its own weight causes leakage of insulating gas at the sealing joint with the busbar cylinders during the opening and closing of the gas-insulated switchgear, especially when the current transformer vibrates during operation. Another purpose of this utility model is to provide a switchgear structure incorporating the aforementioned busbar connection device.

[0005] To achieve the above objectives, the technical solution of the busbar connection device of this utility model is as follows:

[0006] The busbar connection device includes a busbar for connecting to the outgoing terminals of two adjacent gas-filled cabinets, and busbar cylinders for respectively sleeved on the outside of the outgoing terminals of the two adjacent gas-filled cabinets. A current transformer is provided outside the busbar. The current transformer is located between the two busbar cylinders and the two ends of the current transformer are inserted and sealed with the two busbar cylinders. A measuring coil is cast inside the current transformer. The current transformer and the busbar are integrally formed by casting.

[0007] Furthermore, annular shielding pits are provided at both ends of the current transformer where they connect to the busbar.

[0008] Furthermore, the annular shielding pit is an annular groove, which has a bottom wall and a side wall.

[0009] Furthermore, the groove sidewalls of the annular grooves at both ends smoothly transition to the axial end face of the current transformer.

[0010] Furthermore, the current transformer includes a cylindrical main body and plug-in portions extending outward from both ends of the cylindrical main body for insertion into corresponding busbar drums. The plug-in portions at both ends and the cylindrical main body respectively form stepped structures for blocking the ends of the corresponding busbar drums.

[0011] Furthermore, one of the stepped structures at both ends is provided with a measuring coil terminal block for connection to the measuring coil.

[0012] Furthermore, a protective coil is cast inside the current transformer, and a protective coil terminal connected to the protective coil is also provided on the stepped structure with the measuring coil terminal.

[0013] Furthermore, a protective coil is cast inside the current transformer, and the surface of the current transformer is provided with a measuring coil terminal that is connected to the measuring coil and a protective coil terminal that is connected to the protective coil.

[0014] Furthermore, a sealing groove for installing a sealing ring is provided on the outer peripheral surface of the insertion part.

[0015] Beneficial Effects: This utility model improves upon existing busbar connection structures by integrally casting the current transformer and busbar, eliminating the spatial gap between them. This allows the current transformer to be attached to the busbar. When the current transformer is inserted and sealed between its axial ends and the busbar cylinders on both sides, the outgoing terminals of the busbar cylinders on both sides provide effective support for both the current transformer and the busbar. The sealing effect at the insertion point of the current transformer and the busbar cylinders on both sides is more uniform in the circumferential direction. At the same time, when the gas-insulated switchgear vibrates during opening and closing, the current transformer will not move vertically. This ensures a good sealing effect at the sealing assembly point of the current transformer's axial ends and the busbar cylinders on both sides, preventing leakage of insulating gas and improving the vibration resistance and sealing insulation effect of the busbar connection device.

[0016] To achieve the above objectives, the technical solution of the cabinet-side structure of this utility model is as follows:

[0017] The structure consists of two gas-filled cabinets arranged side by side. Each gas-filled cabinet has an outgoing terminal on its top and a busbar connection device. The busbar connection device includes a busbar for connecting to the outgoing terminals of the two adjacent gas-filled cabinets, and busbar cylinders for respectively sleeved on the outside of the outgoing terminals of the two adjacent gas-filled cabinets. A current transformer is provided outside the busbar. The current transformer is located between the two busbar cylinders and its two ends are inserted and sealed with the two busbar cylinders. A measuring coil is cast inside the current transformer. The current transformer and the busbar are integrally formed by casting.

[0018] Furthermore, annular shielding pits are provided at both ends of the current transformer where they connect to the busbar.

[0019] Furthermore, the annular shielding pit is an annular groove, which has a bottom wall and a side wall.

[0020] Furthermore, the groove sidewalls of the annular grooves at both ends smoothly transition to the axial end face of the current transformer.

[0021] Furthermore, the current transformer includes a cylindrical main body and plug-in portions extending outward from both ends of the cylindrical main body for insertion into corresponding busbar drums. The plug-in portions at both ends and the cylindrical main body respectively form stepped structures for blocking the ends of the corresponding busbar drums.

[0022] Furthermore, one of the stepped structures at both ends is provided with a measuring coil terminal block for connection to the measuring coil.

[0023] Furthermore, a protective coil is cast inside the current transformer, and a protective coil terminal connected to the protective coil is also provided on the stepped structure with the measuring coil terminal.

[0024] Furthermore, a protective coil is cast inside the current transformer, and the surface of the current transformer is provided with a measuring coil terminal that is connected to the measuring coil and a protective coil terminal that is connected to the protective coil.

[0025] Furthermore, a sealing groove for installing a sealing ring is provided on the outer peripheral surface of the insertion part.

[0026] Beneficial Effects: This utility model improves upon existing busbar connection structures by integrally casting the current transformer and busbar, eliminating the spatial gap between them. This allows the current transformer to be attached to the busbar. When the current transformer is inserted and sealed between its axial ends and the two busbar cylinders on both sides, the outgoing terminals of the two busbar cylinders provide effective support for both the current transformer and the busbar. The sealing effect at the insertion point of the current transformer and the two busbar cylinders is more uniform in the circumferential direction. Furthermore, when the gas-insulated switchgear vibrates during opening and closing, the current transformer will not experience significant vertical movement. This ensures a good sealing effect at the axial ends of the current transformer and the two busbar cylinders on both sides, preventing leakage of insulating gas and improving the vibration resistance and sealing insulation effect of the busbar connection device. Attached Figure Description

[0027] Figure 1 A schematic diagram of the busbar connection device provided by this utility model installed on a gas-filled cabinet;

[0028] Figure 2 A perspective view of the external structure of the busbar connection device provided by this utility model;

[0029] Figure 3 This is a schematic diagram of the internal structure of the current transformer provided by this utility model.

[0030] Figure 4 for Figure 3 Enlarged view at point D;

[0031] Figure 5 for Figure 3 A-direction view.

[0032] In the diagram: 1. Left busbar drum; 2. Current transformer; 3. Right busbar drum; 4. Busbar; 5. Outgoing terminal; 6. Upper clamp; 7. Lower clamp; 8. Locking bolt; 9. Support pad; 10. Sealing ring; 11. Protection coil; 12. Measuring coil; 13. Sealing groove; 14. Annular shielding pit; 15. Secondary terminal block. Detailed Implementation

[0033] The present invention will be further described in detail below with reference to the embodiments.

[0034] This utility model addresses the technical problem in current switchgear structures where the current transformer's weight causes uneven sealing along its circumference during the plug-in sealing assembly with the busbars on both sides, leading to leakage of insulating gas due to vibration during the opening and closing of the gas-filled switchgear. An improvement is made to the busbar connection device.

[0035] Embodiment 1 of the busbar connection device of this utility model:

[0036] like Figure 1 As shown, the busbar connection device includes a busbar 4 for connecting to the outgoing terminals 5 of two adjacent gas-filled cabinets, and a busbar cylinder for respectively sleeved outside the outgoing terminals 5 of the two adjacent gas-filled cabinets. A current transformer 2 is provided outside the busbar. The current transformer 2 is located between the two busbar cylinders and the two ends of the current transformer 2 are inserted and sealed with the two busbar cylinders. A measuring coil 12 is cast inside the current transformer 2. The current transformer 2 and the busbar 4 are integrally formed by casting.

[0037] By integrally casting the current transformer and the busbar, the spatial gap between the current transformer and the busbar is eliminated, allowing the current transformer to be attached to the busbar. When the current transformer is inserted and sealed between its axial ends and the busbar cylinders on both sides, the outgoing terminals of the busbar cylinders on both sides can provide effective support for the current transformer and the busbar. When the gas-insulated switchgear vibrates during the opening and closing process, the current transformer will not move vertically. This ensures a good sealing effect at the sealing assembly between the current transformer's axial ends and the busbar cylinders on both sides, preventing leakage of insulating gas and improving the vibration resistance and sealing insulation effect of the busbar connection device.

[0038] Furthermore, such as Figure 1 , Figure 3-4 As shown, annular shielding pits 14 are provided at both ends of the current transformer 2 where it is connected to the busbar.

[0039] The ring-shaped shielding pit can reduce the electric field strength at the three-phase interface and play a role in uniformizing the electric field.

[0040] Furthermore, the annular shielding pit 14 is an annular groove, which has a bottom wall and a side wall.

[0041] Furthermore, the sidewalls of the annular grooves at both ends smoothly transition to the axial end face of the current transformer 2, thereby improving the uniform electric field effect.

[0042] Furthermore, such as Figure 1-2As shown, the two busbar drums are left busbar drum 1 and right busbar drum 3, respectively. Both left busbar drum 1 and right busbar drum 3 have top openings and bottom openings. Left busbar drum 1 and right busbar drum 3 also have side openings for plugging and sealing assembly with current transformer 2. The side openings of left busbar drum 1 and right busbar drum 3 are arranged opposite to each other.

[0043] Both busbar reels have top openings for easy access and maintenance of internal components. The bottom openings allow for flanged connection between the two busbar reels and the gas-insulated switchgear. The mounting openings can be sealed with flanges or fitted with matching sealing covers. To further enhance heat dissipation, aluminum alloy busbar reels are preferred. Aluminum alloy has excellent thermal conductivity, facilitating heat dissipation when high current flows through the busbars, preventing overheating damage to the electrical system. Furthermore, aluminum alloy is lightweight, reducing the load on the overall electrical system, and its high strength ensures stability and durability during installation.

[0044] Furthermore, the current transformer 2 includes a cylindrical main body and plug-in portions extending outward from both ends of the cylindrical main body for insertion into corresponding busbar drums. The plug-in portions at both ends and the cylindrical main body respectively form stepped structures for blocking the ends of the corresponding busbar drums.

[0045] The current transformer is inserted into the busbars on both sides at both ends of the axial direction, so that there is no need to install flanges at the side openings of the busbars. Under the premise of ensuring sealing, the current transformer also has a certain tolerance in the axial direction, which can compensate for the horizontal error when the gas-insulated switchgear is connected.

[0046] Furthermore, one of the stepped structures at both ends is provided with a measuring coil terminal block for connection to the measuring coil.

[0047] The measuring coil terminals are located on the end face of the current transformer, which avoids the problem of needing to cut the circumferential side of the current transformer body to obtain the required mounting surface when installing terminals on the circumferential side of the current transformer.

[0048] Furthermore, a protective coil is cast inside the current transformer, and a protective coil terminal connected to the protective coil is also provided on the stepped structure with the measuring coil terminal.

[0049] The protection coil is used to form a protection circuit. The protection coil terminal is set on the end side of the current transformer, which also avoids the problem of needing to cut the circumferential side of the current transformer body to obtain the required mounting surface when installing the terminal on the circumferential side of the current transformer.

[0050] Furthermore, such as Figure 3 and Figure 5 As shown, the stepped structure is provided with secondary terminals 15, which include protection coil terminals and measuring coil terminals, wherein the protection coil terminals and measuring coil terminals are arranged adjacent to each other. This arrangement facilitates the wiring and installation of the protection circuit and the measuring circuit.

[0051] To further improve the sealing effect of the plug-in assembly between the busbar drum and the current transformer 2, such as Figure 1 and Figure 4 As shown, a sealing groove 13 is provided on the outer peripheral surface of the insertion part at both ends of the current transformer 2. In this embodiment, a sealing ring 10 is provided in the sealing groove 13. These sealing rings 10 are usually made of elastic materials, such as rubber or silicone, which can form a more effective seal between the contact surfaces. When the current transformer 2 is inserted into the busbar drum, the sealing ring 10 is compressed and fills any possible tiny gaps, thereby ensuring that the filled insulating gas will not leak through these gaps.

[0052] In this embodiment, busbar 4 is a tubular busbar. The tubular busbar has a hollow structure, which optimizes current distribution, ensuring that current carrying capacity is not affected. Furthermore, it improves current transmission efficiency by reducing the skin effect. Compared to a solid busbar, it uses less conductive material, significantly reducing the amount of copper or aluminum used, thereby lowering material costs. The hollow internal space helps dissipate heat, improving heat dissipation performance to a certain extent. This means that the busbar can more effectively prevent overheating under high loads, improving system stability and safety. Busbar 4 can be a copper tube or an aluminum tube.

[0053] The two ends of the tubular busbar are connected to the outgoing terminal 5 on the gas-filled switchgear using clamp assemblies. The clamp assembly includes an upper clamp 6, a lower clamp 7, a locking bolt 8, a support pad 9, etc. For the specific structure of the clamp assembly, please refer to the detailed description in the invention patent application with publication number CN118920284A, which will not be repeated here.

[0054] In other embodiments of the busbar connection device: the annular shielding pit may not be provided at the connection positions between the axial ends of the current transformer and the busbar, and the axial ends of the current transformer are planes.

[0055] In other embodiments of the busbar connection device: the annular shielding pit is an annular groove, and the annular groove may also be provided with only groove sidewalls, such as the longitudinal section of the annular groove being V-shaped.

[0056] In other embodiments of the busbar connection device, the groove sidewalls of the annular grooves at both ends and the axial end face of the current transformer may not have a smooth transition, but rather a sharp corner transition.

[0057] In other embodiments of the busbar connection device: the two end plug-in parts and the cylindrical main body may not have a stepped structure, such as the outer diameter of the current transformer being the same as that of a cylinder of equal diameter.

[0058] In other embodiments of the busbar connection device: the measuring terminals may not be located on the stepped structure, but may be located on the outer peripheral wall of the current transformer.

[0059] In other embodiments of the busbar connection device, the current transformer may not be equipped with a protection coil.

[0060] In other embodiments of the busbar connection device: the measuring coil terminal and the protection coil terminal may not be adjacent to each other, for example, they may be located at the radial ends of the same stepped structure, or they may not be located on the same stepped structure of the current transformer, for example, one of them may be on the stepped structure and the other may be on the outer peripheral wall.

[0061] In other embodiments of the busbar connection device: the sealing groove can also be provided on the wall of the busbar drum at the insertion and mating point between the busbar drum and the current transformer, such as the end of the current transformer being sleeved outside the busbar drum, and the outer wall of the busbar drum being provided with a sealing groove.

[0062] In other embodiments of the busbar connection device, the top opening may not be provided on the busbar drum, but a maintenance opening may be provided on the side of the busbar drum.

[0063] The embodiment of the parallel cabinet structure in this utility model is as follows: The parallel cabinet structure includes two gas cabinets arranged side by side. The gas cabinets are provided with outgoing terminals on the top and also include a busbar connection device. The structure of the busbar connection device is the same as that of the busbar connection device in any of the above embodiments, and will not be repeated here.

[0064] Finally, it should be noted that the above description is only a preferred embodiment of this utility model and is not intended to limit this utility model. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still make modifications to the technical solutions described in the foregoing embodiments without creative effort, or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A busbar connection device, comprising a busbar for connecting to the outgoing terminals of two adjacent gas-insulated switchgear, and busbar cylinders respectively sleeved outside the outgoing terminals of the two adjacent gas-insulated switchgear, wherein a current transformer is provided outside the busbar, the current transformer is located between the two busbar cylinders and the two ends of the current transformer are inserted and sealed with the two busbar cylinders, and a measuring coil is cast inside the current transformer, characterized in that: The current transformer and the busbar are integrally formed by casting.

2. The busbar connection device according to claim 1, characterized in that: Annular shielding pits are provided at both ends of the current transformer where they connect to the busbar.

3. The busbar connection device according to claim 2, characterized in that: The annular shielding pit is an annular groove, which has a bottom wall and a side wall.

4. The busbar connection device according to claim 3, characterized in that: The groove sidewalls of the annular grooves at both ends smoothly transition to the axial end face of the current transformer.

5. The busbar connection device according to any one of claims 1-4, characterized in that: The current transformer includes a cylindrical main body and plug-in portions extending outward from both ends of the cylindrical main body for insertion into corresponding busbar drums. The plug-in portions at both ends and the cylindrical main body respectively form stepped structures for blocking the ends of the corresponding busbar drums.

6. The busbar connection device according to claim 5, characterized in that: One of the stepped structures at both ends is equipped with a measuring coil terminal block for connection to the measuring coil.

7. The busbar connection device according to claim 6, characterized in that: The current transformer has a protective coil inside, and the stepped structure with the measuring coil terminal also has a protective coil terminal connected to the protective coil.

8. The busbar connection device according to any one of claims 1-4, characterized in that: The current transformer has a protective coil inside, and the surface of the current transformer has a measuring coil terminal that connects to the measuring coil and a protective coil terminal that connects to the protective coil.

9. The busbar connection device according to claim 5, characterized in that: The outer circumferential surface of the plug-in portion is provided with a sealing groove for installing a sealing ring.

10. A parallel cabinet structure, comprising two gas-insulated cabinets arranged side by side, each gas-insulated cabinet having an outgoing terminal on its upper part, and further comprising a busbar connection device, characterized in that: The busbar connection device is the busbar connection device as described in any one of claims 1-9.

Images