Shielding device for insulating tubular bus joint and tubular bus connection structure

Abstract

The invention relates to the technical field of shielding of equipment or elements to an electric field or a magnetic field, in particular to a shielding device for an insulating tubular bus joint and a tubular bus connection structure. The shielding device for the insulated tubular bus joint comprises an epoxy sleeve, a high-voltage shielding mesh cylinder and a low-voltage shielding mesh cylinder are arranged in the wall of the epoxy sleeve, and the epoxy sleeve, the high-voltage shielding mesh cylinder and the low-voltage shielding mesh cylinder are integrally formed by adopting an APG process; the high-voltage shielding net cylinder is connected with a conductor which extends into an inner hole of the epoxy sleeve and is used for being connected with a tubular bus, the high-voltage shielding net cylinder is located in an inner hole of the low-voltage shielding net cylinder, the high-voltage shielding net cylinder and the low-voltage shielding net cylinder are arranged at intervals, a grounding insert is arranged on the outer wall of the epoxy sleeve, and the low-voltage shielding net cylinder is communicated with the grounding insert. In the production process, the APG process is adopted for integral forming, and the integral forming process can balance the pressure in each part of the mold, so that the production period is shortened to about 1 hour, the quality of the produced epoxy sleeve can be higher, and the production efficiency is remarkably improved.

Description

Technical Field

[0001] The invention relates to the technical field of shielding of equipment or components against electric fields or magnetic fields, and in particular to a shielding device for an insulating tubular busbar joint and a tubular busbar connection structure. Background Art

[0002] In substations and distribution stations, insulated tubular busbars are used for interconnection between distribution devices and electrical equipment. Insulated tubular busbars can effectively transmit power signals, maintain signal stability and security, and isolate various interference signals to ensure the accuracy and reliability of the power system.

[0003] In order to ensure the high efficiency, safety and stability of power transmission, a shielding device must be installed at each section of the tubular busbar joint. There is a grounding layer outside the shielding device to achieve effective grounding and ensure that the electric potential is zero, preventing the influence of electromagnetic interference on the power system. The shielding device usually includes a conductor shielding layer, a main insulating layer, an outer shielding layer, and a jacket protective layer. The conductor shielding layer is used to improve the electric field distribution of the tubular busbar; a main insulating layer is provided outside the conductor shielding layer, and the main insulating layer is generally an insulating material impregnated with epoxy resin; an outer shielding layer made of a high-strength braided copper mesh belt or other metal is provided outside the main insulating layer to further shield the electromagnetic field, thereby reducing line losses; the outermost layer of the shielding device is a jacket protective layer, which uses a polyolefin polymer insulating sheath or other UV-resistant insulating three-color sheath to protect the internal structure from the influence of the external environment, such as moisture, dust, foreign objects, etc., while providing additional mechanical protection.

[0004] In the prior art, the shielding device at the tubular busbar joint is mostly in the form of an insulating sleeve covering the conductor connection part. However, the insulating sleeve used here is usually wrapped with insulating, semi-conductive (sticky) electrical crepe paper tape and made by epoxy resin impregnation vacuum casting process. The epoxy resin impregnation vacuum casting process is to pour the epoxy impregnation liquid into the insulating, semi-conductive (sticky) electrical crepe paper tape wrapped on the insulating sleeve in a vacuum container. At this time, it is in a vacuum state. Due to the effect of external pressure, the epoxy impregnation liquid will penetrate into the electrical crepe paper tape. Wait for a period of time for the impregnation liquid to fully penetrate; after the impregnation is completed, oxygen is introduced into the container. After the air pressure inside the container is balanced with the external environment, the insulating sleeve is taken out and placed at room temperature for two or three days to solidify the epoxy impregnation liquid, and finally the insulating sleeve is polished; the production cycle usually takes 5 to 6 days, the overall processing process is time-consuming, and the production efficiency is low.

[0005] The Chinese utility model patent with the authorization announcement number CN221688283U and the authorization announcement date 2024 / 09 / 10 discloses an injection-molded shielding cylinder for an intermediate joint of an insulating tubular busbar. The injection-molded shielding cylinder for an intermediate joint of an insulating tubular busbar of the patent includes an insulating layer, a conductor cavity with large ends and a small middle section is formed inside the insulating layer, a conductor shielding layer is arranged in the middle section of the conductor cavity, and an intermediate shielding layer is arranged outside the insulating layer; the conductor shielding layer, the insulating layer, and the intermediate shielding layer are integrally formed to form a composite main insulating layer as an integral solid insulating layer, and there is also a metal grounding layer outside the integral solid insulating layer. The injection-molded shielding cylinder for the intermediate joint of an insulating tubular busbar of the patent plays a shielding role through the cooperation of the conductor shielding layer, the insulating layer, the intermediate shielding layer, and the metal grounding layer. The production process of the device is to first mold the innermost conductor shielding layer, and then mold the insulation layer outside the conductor shielding layer; however, during the molding process of the insulation layer, the materials used will decompose to produce gas, but this gas cannot be discharged from the inner surface of the insulation layer close to the conductor shielding layer, but this gas cannot be completely discharged through the outer surface of the insulation layer, and some gas will remain inside the insulation layer injection molding body, which will cause bubble defects inside the insulation layer during cooling. Under the joint action of the conductor shielding layer and the metal shielding layer, the insulation layer is broken down at the bubble defects in the insulation layer. Therefore, it is necessary to set an intermediate shielding layer outside the insulation layer to further isolate the conductor shielding layer and the metal grounding layer, which leads to the integrated molding process of the overall solid insulation layer of the device being divided into several moldings; after the overall solid insulation layer is molded, multiple processes are required to process and arrange the metal shielding layer and the outer jacket protective cover outside the overall solid insulation layer. Although the injection molding shielding tube of the insulating tubular busbar intermediate joint simplifies the structure of the shielding device to a certain extent and adopts an integrated molding process, its integrated molding is essentially multiple molding, which requires multiple processes to complete, and the improvement of production efficiency and performance is not significant. Summary of the invention

[0006] The object of the present invention is to provide a shielding device for an insulating tubular busbar joint and a tubular busbar connection structure to solve the problem of low production efficiency of the shielding device for an insulating tubular busbar joint.

[0007] In order to solve the above problems, the shielding device for insulating tubular busbar joint of the present invention adopts the following technical solutions: A shielding device for an insulated tubular busbar joint comprises an epoxy sleeve, wherein a high-voltage shielding mesh tube and a low-voltage shielding mesh tube are arranged in the tube wall of the epoxy sleeve, and the epoxy sleeve, the high-voltage shielding mesh tube and the low-voltage shielding mesh tube are integrally formed by adopting the APG process; the high-voltage shielding mesh tube is connected to a conductor extending into the inner hole of the epoxy sleeve for connecting the tubular busbar, the high-voltage shielding mesh tube is located in the inner hole of the low-voltage shielding mesh tube and is arranged at an interval with the low-voltage shielding mesh tube, and a grounding insert is arranged on the outer wall of the epoxy sleeve, and the low-voltage shielding mesh tube is connected to the grounding insert.

[0008] Furthermore, a portion of the inner wall of the middle section of the epoxy sleeve is raised to form a centering support ring, and a high-voltage conductor connection insert is pre-buried in the centering support ring.

[0009] Furthermore, both ends of the high-voltage shielding mesh tube are provided with curling edges.

[0010] Furthermore, both ends of the low-voltage shielding mesh tube are provided with curling edges.

[0011] Furthermore, the length of the high-voltage shielding mesh tube is 1 / 3-2 / 3 of the length of the epoxy sleeve.

[0012] Furthermore, the length of the low-voltage shielding mesh cylinder is 1 / 3 of the length of the high-voltage shielding mesh cylinder.

[0013] Furthermore, a flange is provided on the outer wall of the epoxy sleeve, and a grounding insert is embedded in each of the four corners of the flange.

[0014] Furthermore, the outer wall of the epoxy sleeve is provided with climbing sheds with long and short intervals, and the two ends of the climbing sheds extend to the two ends of the epoxy sleeve.

[0015] Beneficial effects: The shielding device for the insulated tubular busbar joint of the present invention is a pioneering invention. Through this scheme, two layers of shielding mesh are used inside the insulating sleeve of the shielding device to optimize the field strength; wherein the high-voltage shielding mesh tube is directly connected to the middle joint of the busbar to meet the needs of high-voltage shielding; the low-voltage shielding mesh tube is connected to the grounding insert to achieve a surface potential of 0 for the product. The insulating material adopts outdoor epoxy resin material to meet the requirements of UV resistance and aging resistance. The product adopts the APG process to be integrally formed by the mold. The shielding device for the insulated tubular busbar joint is integrally formed by the mold using the APG process during the production process. The integral molding process can balance the pressure inside the mold, which can ensure that the quality of the epoxy sleeve produced is higher, and the production cycle is shortened from the original minimum of 3 days to about 1 hour, and the production efficiency is significantly improved.

[0016] The tubular busbar connection structure of the present invention adopts the following technical solutions: A tubular busbar connection structure comprises two coaxially connected tubular busbars, wherein a shielding device is arranged at the connection of the two tubular busbars, wherein the shielding device comprises an epoxy sleeve, wherein a high-voltage shielding mesh tube and a low-voltage shielding mesh tube are arranged in the tube wall of the epoxy sleeve, and the epoxy sleeve, the high-voltage shielding mesh tube and the low-voltage shielding mesh tube are integrally formed by an APG process; the high-voltage shielding mesh tube is connected to a conductor extending into an inner hole of the epoxy sleeve for connecting the tubular busbar, the high-voltage shielding mesh tube is located in the inner hole of the low-voltage shielding mesh tube and is spaced apart from the low-voltage shielding mesh tube, and a grounding insert is arranged on the outer wall of the epoxy sleeve, and the low-voltage shielding mesh tube is connected to the grounding insert.

[0017] Furthermore, a portion of the inner wall of the middle section of the epoxy sleeve is raised to form a centering support ring, and a high-voltage conductor connection insert is pre-buried in the centering support ring.

[0018] Furthermore, both ends of the high-voltage shielding mesh tube are provided with curling edges.

[0019] Furthermore, both ends of the low-voltage shielding mesh tube are provided with curling edges.

[0020] Furthermore, the length of the high-voltage shielding mesh tube is 1 / 3-2 / 3 of the length of the epoxy sleeve.

[0021] Furthermore, the length of the low-voltage shielding mesh cylinder is 1 / 3 of the length of the high-voltage shielding mesh cylinder.

[0022] Furthermore, a flange is provided on the outer wall of the epoxy sleeve, and a grounding insert is embedded in each of the four corners of the flange.

[0023] Furthermore, the outer wall of the epoxy sleeve is provided with climbing sheds with long and short intervals, and the two ends of the climbing sheds extend to the two ends of the epoxy sleeve.

[0024] Beneficial effects: The tubular busbar connection structure of the present invention is a pioneering invention. Through this solution, two layers of shielding nets are used inside the insulating sleeve of the shielding device to optimize the field strength; the high-voltage shielding net tube is directly connected to the middle joint of the busbar to meet the needs of high-voltage shielding; the low-voltage shielding net tube is connected to the grounding wire of the busbar system to achieve a product surface potential of 0. The insulating material adopts outdoor epoxy resin material to meet the requirements of UV resistance and aging. The shielding device for the insulated tubular busbar joint is integrally formed by the mold using the APG process during the production process. The integral molding process can balance the pressure inside the mold, which can ensure that the quality of the produced epoxy sleeve is higher, and the production cycle is shortened from the original minimum of 3 days to about 1 hour, and the production efficiency is significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of an embodiment of a shielding device for an insulating tubular busbar joint of the present invention; Figure 2 The three-dimensional outer contour schematic diagram of an embodiment of the shielding device for the insulating tubular busbar joint of the present invention.

[0026] In the figure: 1. High-voltage shielding mesh tube; 2. Low-voltage shielding mesh tube; 3. Epoxy sleeve; 4. Climbing skirt; 5. Grounding insert; 6. Centering support ring; 7. High-voltage conductor connection insert. DETAILED DESCRIPTION

[0027] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0028] The embodiments of the shielding device for insulating tubular busbar joint of the present invention are as follows: The shielding device for the insulating tubular busbar joint of the present invention adopts a structure in which the shielding net is embedded in the epoxy sleeve. During the production process, the shielding net and the epoxy sleeve are integrally formed by a mold using the APG process, which significantly improves the production efficiency of the shielding device.

[0029] As a basic solution, the main material of the shielding device for the insulated tubular busbar joint of the present invention is outdoor epoxy resin. The weather resistance and stability of the outdoor epoxy resin meet the use requirements of the shielding device for the insulated tubular busbar joint of the present invention, and can operate stably for a long time in harsh outdoor environments; most importantly, the outdoor epoxy resin has adhesion, so the epoxy sleeve can firmly bond the high-voltage shielding mesh tube 1 and the low-voltage shielding mesh tube 2 provided in the pipe wall. During production, the epoxy sleeve 3, the high-voltage shielding mesh tube 1, and the low-voltage shielding mesh tube 2 are integrally formed using the APG process, and the flow and curing of the epoxy resin are accurately controlled in the mold, thereby ensuring the The device of the invention has high dimensional accuracy and shape stability, wherein the mesh design of the high-voltage shielding mesh tube 1 and the low-voltage shielding mesh tube 2 facilitates the flow of the casting material in the mold, avoiding the generation of bubble defects; the high-voltage shielding mesh tube is connected to a conductor extending into the inner hole of the epoxy sleeve for connecting the tubular busbar, effectively avoiding local discharge between the conductor and the epoxy sleeve 3, thereby improving the electric field distribution and reducing faults caused by electric field concentration; the high-voltage shielding mesh tube is located in the inner hole of the low-voltage shielding mesh tube and is arranged at intervals with the low-voltage shielding mesh tube, and the low-voltage shielding mesh tube 2 can better block the interference of the external electromagnetic field, reduce or eliminate the interference of the internal signal of the busbar; such as Figure 1 As shown, the outer wall of the epoxy sleeve 3 is provided with a grounding insert 5, and the low-voltage shielding mesh tube 2 is connected to the grounding insert 5. The low-voltage shielding mesh tube 2 has good electrical conductivity and can introduce the static charge inside the busbar into the grounding insert 5, which can reduce faults caused by static electricity accumulation. At the same time, when the busbar is damaged, the leaked current can also flow into the grounding insert 5 along the low-voltage shielding mesh tube, thereby preventing people or animals from contacting live equipment and getting electric shock, effectively ensuring personal safety.

[0030] As a preferred embodiment, a portion of the inner wall of the middle section of the epoxy sleeve 3 is raised to form a centering support ring 6, and the centering support ring 6 forms a conductor centering hole. The conductor centering hole provides a better path for the joint during the busbar joint process, and also ensures the stability and reliability of the structure at the busbar joint, preventing the joint from shifting during use. A high-voltage conductor connecting insert 7 is pre-embedded in the centering support ring. The pre-embedded connecting insert is connected to the centering support ring through a pre-embedded rigid conductor. In other embodiments, the pre-embedded rigid conductor can be replaced with a soft conductor.

[0031] As a preferred embodiment, the two ends of the high-voltage shielding mesh tube 1 are provided with curling edges. The curling design of the high-voltage shielding mesh tube 1 forms an axial limit with the epoxy sleeve, and at the same time helps to achieve uniform distribution of the electric field, further improving the shielding effect and service life; the two ends of the high-voltage shielding mesh tube are straight and the adhesion of the epoxy resin material used in the epoxy sleeve can also be used to achieve fixed limit and achieve uniform electric field distribution, thereby reducing defects caused by electric field concentration.

[0032] As a preferred embodiment, the two ends of the low-voltage shielding mesh tube 2 are provided with curling edges. The curling design of the low-voltage shielding mesh tube 2 forms an axial limit with the epoxy sleeve, which helps to shield the magnetic field and further improve the shielding effect and service life; the two ends of the low-voltage shielding mesh tube are straight and the adhesion of the epoxy resin material used in the epoxy sleeve can also be used to achieve fixed limit and shield the magnetic field, thereby reducing or eliminating interference with the internal signal of the busbar.

[0033] As a preferred embodiment, the length of the high-voltage shielding mesh tube 1 is one-third to two-thirds of the length of the entire epoxy sleeve 3. Under the premise of ensuring the effectiveness and reliability of the device, reducing a part of the length of the high-voltage shielding mesh tube 1 can avoid unnecessary material waste and cost increase; in other embodiments, the high-voltage shielding mesh tube is the same length as the epoxy sleeve. This arrangement facilitates positioning of the high-voltage shielding mesh tube during the molding process and facilitates the implementation of the APG process.

[0034] As a preferred implementation manner, while ensuring that the conductivity, grounding performance and shielding effect of the low-voltage shielding mesh tube 2 meet the requirements, the length of the low-voltage shielding mesh tube 2 is one-third of the length of the high-voltage shielding mesh tube 1, which can reduce the waste of resources to a certain extent; in other implementation manners, the low-voltage shielding mesh tube is the same length as the epoxy sleeve. This arrangement facilitates the positioning of the high-voltage shielding mesh tube during the molding process and facilitates the implementation of the APG process.

[0035] As a preferred embodiment, the outer wall of the epoxy sleeve 3 is provided with a flange, which has a compact structure and reliable connection. Figure 2As shown, a grounding insert 5 is embedded in each of the four corners of the flange. Installing the grounding insert 5 at the four corners of the flange can ensure that the grounding current is distributed more evenly on the flange, thereby improving the effectiveness and reliability of grounding. The four corners of the flange are usually where bolts or other fasteners are installed, so they are also ideal locations for installing the grounding insert 5.

[0036] As a preferred embodiment, the outer wall of the epoxy sleeve 3 is provided with climbing sheds 4 with long and short intervals, and the two ends of the climbing sheds extend to the two ends of the epoxy sleeve 3. The long and short interval arrangement can more effectively utilize the extended creepage distance effect of the sheds. In a severely polluted or humid environment, a longer shed can provide a longer creepage distance, thereby significantly improving the pollution flashover voltage of the equipment. At the same time, the long and short interval arrangement can also reduce the accumulation of dirt between the sheds to a certain extent, because the gaps between the shorter sheds may be more easily washed clean by rain or wind, thereby further reducing the risk of pollution flashover accidents. Compared with climbing sheds 4 of uniform length, the long and short interval arrangement avoids unnecessary waste. This arrangement helps to achieve economical and reasonable configuration and reduce overall costs.

[0037] The implementation process of this embodiment is as follows: during installation, the joint part of the insulating tubular busbar is first processed, such as polishing, cleaning, etc., to ensure the surface quality and connection effect of the joint, and then the epoxy sleeve 3 is put on a busbar joint, and its position is accurate and fixed reliably, and then the other busbar is inserted into the epoxy sleeve 3 from the other end of the epoxy sleeve 3, and the joint is completed at the centering support ring 6 in the epoxy sleeves 3 of the two busbars. During the installation process, the high-voltage conductor connection insert 7 enhances the stability of the busbar connected in the sleeve. The grounding insert 5 is connected to the busbar through the low-voltage shielding mesh tube 2 to ensure the grounding effect.

[0038] When the busbar is energized, the shielding device effectively controls the electric field distribution at the busbar joint through the high-voltage shielding mesh tube 1 and the low-voltage shielding mesh tube 2 inside it and the characteristics of the insulating material, effectively preventing the occurrence of electric field concentration and local discharge, thereby protecting the insulation performance of the busbar system. The epoxy sleeve 3 provides an additional insulation layer for the busbar joint, further enhancing the insulation performance of the system. Even in the case of harsh external environment or failure of the busbar system, the shielding device can effectively isolate the fault point and prevent the expansion of the accident.

[0039] The embodiments of the tubular busbar connection structure of the present invention are as follows: The tubular busbar connection structure comprises two coaxially connected tubular busbars, and a shielding device is provided at the connection between the two tubular busbars, wherein the embodiment of the shielding device has been described above and will not be repeated here.

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the contents of the description and drawings of the present invention should also be included in the protection scope of the present invention.

Claims

1. A shielding device for an insulating tubular busbar joint, characterized in that: It includes an epoxy sleeve, in which a high-voltage shielding mesh tube and a low-voltage shielding mesh tube are arranged in the tube wall of the epoxy sleeve, and the epoxy sleeve, the high-voltage shielding mesh tube and the low-voltage shielding mesh tube are integrally formed by adopting the APG process; the high-voltage shielding mesh tube is connected to a conductor extending into the inner hole of the epoxy sleeve for connecting the tubular busbar, the high-voltage shielding mesh tube is located in the inner hole of the low-voltage shielding mesh tube and is arranged at intervals with the low-voltage shielding mesh tube, and a grounding insert is provided on the outer wall of the epoxy sleeve, and the low-voltage shielding mesh tube is connected to the grounding insert.

2. The shielding device for an insulating tubular busbar joint according to claim 1, characterized in that: A portion of the inner wall of the middle section of the epoxy sleeve is raised to form a centering support ring, and a high-voltage conductor connection insert is pre-buried in the centering support ring.

3. The shielding device for an insulating tubular busbar joint according to claim 1, characterized in that: The two ends of the high-voltage shielding mesh cylinder are provided with curling edges.

4. The shielding device for an insulating tubular busbar joint according to claim 1, characterized in that: The two ends of the low-voltage shielding mesh cylinder are provided with curling edges.

5. The shielding device for an insulating tubular busbar joint according to claim 1 or 3, characterized in that: The length of the high-voltage shielding mesh tube is 1 / 3-2 / 3 of the length of the epoxy sleeve.

6. The shielding device for an insulating tubular busbar joint according to claim 1 or 4, characterized in that: The length of the low-voltage shielding mesh cylinder is 1 / 3 of the length of the high-voltage shielding mesh cylinder.

7. The shielding device for an insulating tubular busbar joint according to any one of claims 1 to 4, characterized in that: The outer wall of the epoxy sleeve is provided with a flange, and a grounding insert is respectively embedded in the four corners of the flange.

8. The shielding device for an insulating tubular busbar joint according to any one of claims 1 to 4, characterized in that: The outer wall of the epoxy sleeve is provided with climbing sheds with long and short intervals, and the two ends of the climbing sheds extend to the two ends of the epoxy sleeve.

9. The shielding device for an insulating tubular busbar joint according to claim 7, characterized in that: The outer wall of the epoxy sleeve is provided with climbing sheds with long and short intervals, and the two ends of the climbing sheds extend to the two ends of the epoxy sleeve.

10. A tubular busbar connection structure, comprising two coaxially connected tubular busbars, wherein a shielding device is provided at the connection of the two tubular busbars, characterized in that: The shielding device is a shielding device for an insulating tubular busbar joint as described in any one of claims 1 to 9.

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