Plug-in lightning arrester
By integrating a high-voltage electrode and a high-dielectric-strength injection-molded layer design, combined with a liquid silicone insulation layer and a graphite semi-conductive silicone shielding layer, the partial discharge problem of pluggable surge arresters is solved, achieving electric field homogenization and improved insulation performance, while reducing production costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-12
- Publication Date
- 2026-04-07
AI Technical Summary
Existing plug-in surge arresters are prone to partial discharge under high voltage, which leads to the deterioration and breakdown of insulation materials. Their structure relies on semi-conductive equalizing caps and adhesives, which pose a risk of poor bonding.
It adopts an integrated high-voltage electrode and a high dielectric strength injection molding layer design, combined with a liquid silicone insulating layer and a graphite semi-conductive silicone shielding layer. It uses a necked structure to uniformly generate an electric field, eliminating the need for a traditional equalizing cap. It uses PA66 and 30% glass fiber composite material to form a sealed cavity and cover it with liquid silicone.
It effectively reduces electric field concentration, prevents partial discharge, improves product stability and reduces production costs, and enhances insulation performance and reliability.
Smart Images
Figure CN224096500U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to the technical field of lightning arresters, and in particular to a plug-in lightning arrester. BACKGROUND
[0002] The plug-in lightning arrester belongs to the lightning arrester with insulation and / or shielding outer sleeve in the national standard GB / T11032-2020 AC gapless metal oxide lightning arrester, which provides system insulation. The lightning arrester is a device and equipment installed in a cabinet body and used for protecting power distribution equipment and circuits. The product is mainly composed of a shielding shell, a semi-conductive shielding layer, an insulation layer, a lightning arrester valve piece group, and corresponding accessories such as a high-voltage contact and a conductive rod, and is a very compact lightning arrester product.
[0003] Due to the unique structural features of the lightning arrester, such as the shell made of shielding metal material connected to the ground to protect the internal parts from environmental influences, the insulation layer composed of insulating materials and the semi-conductive shielding layer, and the shell connected to the ground, the transmission of high-voltage electric field is blocked, which can effectively reduce the installation spacing, increase the installation density, and thus reduce the overall equipment volume.
[0004] At present, the internal core of the conventional plug-in lightning arrester is composed of a high-voltage part, a contact, an anti-corona gasket, a high-voltage electrode, and a semi-conductive voltage-sharing cap. The semi-conductive voltage-sharing cap is processed by semi-conductive ethylene-propylene-diene rubber molding and is bonded to the resistance sheet core and the high-voltage conductive rod by adhesive during assembly, which is used to cover the high-voltage electrode uniform electric field to reduce internal partial discharge. However, in the design and trial production of the plug-in lightning arrester, it is found that the structure is heavily dependent on the semi-conductive voltage-sharing cap and the corresponding primer adhesive. If there is a bonding problem or poor contact of the semi-conductive voltage-sharing cap, it will cause serious over-standard partial discharge, which will further cause the performance degradation of the insulation material, and long-term use will cause insulation breakdown and damage.
[0005] Due to the specific features of the structure, the performance requirements for the insulation material (liquid silicone rubber) are extremely high, and the product works under a voltage of several thousand volts to tens of thousands of volts for a long time, which is a great challenge for product design. Among them, the solution to the design of insulation strength and partial discharge is a difficult point in the design of the product. UTILITY MODEL CONTENTS
[0006] In view of this, in order to solve the above-mentioned problems existing in the prior art, the purpose of the utility model is to provide a plug-in lightning arrester to achieve the purpose of averaging the electric field and effectively reducing the electric field concentration, and optimizing the process design to avoid the phenomenon of partial discharge.
[0007] The utility model discloses a technical scheme adopted: a plug-in lightning arrester, the lightning arrester includes valve plate group and the low voltage electrode connected to one end of valve plate group, the lightning arrester still includes:
[0008] Integrated high voltage electrode, one end of the integrated high voltage electrode is sequentially equipped with antielectric -glow gasket and high voltage contact, and the other end is connected with the valve plate group;
[0009] High dielectric strength injection layer, the outer lateral wall of integrated high voltage electrode, valve plate group and low voltage electrode is integrally formed by high dielectric strength injection layer injection molding;
[0010] Wherein, the one end of integrated high voltage electrode connected valve plate group is smooth continuous necking shape, and the material of integrated high voltage electrode is conductive metal material, for example: aluminum, iron or copper and so on conductive metal.
[0011] Further, the lightning arrester still includes: liquid silicone rubber insulation layer, the liquid silicone rubber insulation layer and integrated high voltage electrode, valve plate group and low voltage electrode form a sealed cavity, and the high dielectric strength injection layer is covered inside the sealed cavity
[0012] Further, one end of the high dielectric strength injection layer is flush with the end head lateral wall of the integrated high voltage electrode, and the end does not extend to the end head end face of the integrated high voltage electrode, and the other end of the high dielectric strength injection layer does not extend to the end head end face of the low voltage electrode and is covered in the liquid silicone rubber insulation layer.
[0013] Further, the integrated high voltage electrode is formed by high voltage conductive rod and high voltage electrode integrated and combined, to replace the high voltage conductive rod and high voltage electrode in the traditional structure.
[0014] Further, the high dielectric strength injection layer adopts the composite material formed by the combination of PA66 and 30% glass fiber, and the dielectric strength of the composite material reaches more than 45kV / mm.
[0015] Further, the outer part of the liquid silicone rubber insulation layer is sprayed with graphite semiconductive silicone rubber to form a semiconductor shielding layer, for improving electric field distribution and preventing partial discharge.
[0016] Further, one end of the liquid silicone rubber insulation layer is flush with the end face of the antielectric -glow gasket, and the other end is flush with the end face of the low voltage electrode, to ensure that the liquid silicone rubber insulation layer completely covers the high dielectric strength injection layer inside it.
[0017] Further, the necking angle of the necking shape is 145°-160°, preferably, the necking angle is 150°-155°, and the necking angle can realize electric field homogenization and normalize high gradient electric field in the high dielectric strength injection layer.
[0018] Furthermore, the valve plate assembly is a zinc oxide valve plate assembly.
[0019] The beneficial effects of this utility model are as follows:
[0020] 1. The pluggable surge arrester of this utility model, by setting a necked structure and injection molding high dielectric strength material on the integrated high voltage electrode, confines the position with a high electric field gradient inside the high dielectric strength material, and prevents it from being conducted into the liquid silicone rubber system with a low dielectric strength. This effectively reduces the performance requirements of the external insulation material and effectively reduces the electric field concentration, preventing partial discharge.
[0021] 2. The plug-in surge arrester of this utility model eliminates the equalizing shield cap that is set on the high-voltage end of the traditional surge arrester. From the perspective of manufacturing process, it reduces one component, further improves the overall stability of the product and reduces production costs. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the overall structure of the plug-in surge arrester provided by this utility model;
[0023] The attached diagram is labeled as follows:
[0024] 1-High voltage contact; 2-Anti-corona gasket; 3-Integrated high voltage electrode; 4-High dielectric strength injection molding layer; 5-Liquid silicone insulating layer; 6-Semi-conductive shielding layer; 7-Valve plate assembly; 8-Low voltage electrode. Detailed Implementation
[0025] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0027] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments of the present invention can be combined with each other. It should also be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0028] In the description of the embodiments of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. The accompanying drawings in the embodiments are used to clearly and completely describe the technical solutions in the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0029] Example 1
[0030] like Figure 1 As shown, this embodiment specifically provides a pluggable surge arrester, which includes a valve plate assembly 7 and a low-voltage electrode 8 connected to one end of the valve plate assembly 7. The low-voltage electrode 8 can also be referred to as a grounding electrode. The surge arrester is characterized by further including an integrated high-voltage electrode 3. This integrated high-voltage electrode 3 is formed by combining a high-voltage conductive rod and a high-voltage electrode, replacing the function of the conductive rod and high-voltage electrode in traditional surge arresters. The integrated high-voltage electrode is made of a conductive metal material, such as aluminum, iron, or copper. An anti-corona discharge pad 2 and a high-voltage contact 1 are sequentially installed at one end of the integrated high-voltage electrode 3, and the other end is connected to the valve plate assembly 7. The high-voltage contact 1 is used to reliably connect the surge arrester to the high-voltage line or equipment of the power system, ensuring normal current flow. The anti-corona gasket 2 is used to prevent corona discharge. The valve assembly 7 is a zinc oxide valve assembly, which is a surge arrester core valve assembly composed of zinc oxide surge arrester valves, utilizing its excellent nonlinear resistance characteristics to achieve overvoltage protection. It should be noted that the anti-corona gasket 2, high-voltage contact 1, and valve assembly 7 in this embodiment are all conventional components of pluggable surge arresters, and will not be described in detail here.
[0031] Based on the above-designed integrated high-voltage electrode 3, in this embodiment, the integrated high-voltage electrode 3, the valve plate group 7, and the outer wall of the low-voltage electrode 8 are injection molded with a high dielectric strength injection layer 4 and formed into one piece. That is, the integrated electrode, the valve plate group 7, and the low-voltage electrode 8 at the tail end are formed by injection molding with a high dielectric strength injection layer 4 (PA66+30GF) in one step. The high dielectric strength injection layer 4 is a composite material formed by combining PA66 and 30% glass fiber, and its dielectric strength can reach more than 45kV / mm.
[0032] Since the high dielectric strength injection molding layer 4 is a composite material formed by combining PA66 and 30% glass fiber, and PA66 has strong water absorption, the ends of the integrated high voltage electrode 3 and low voltage electrode 8 are not entirely injection molded with the high dielectric strength composite material. Instead, a layer of liquid silicone insulating layer 5 with non-absorbent properties is wrapped around the outside of the high dielectric strength injection molding layer 4. The liquid silicone insulating layer 5, the integrated high voltage electrode 3, the valve plate assembly 7, and the low voltage electrode 8 form a sealed cavity, and the high dielectric strength injection molding layer 4 is wrapped inside the sealed cavity. Since the high dielectric strength injection molding layer 4 does not come into contact with the outside air, it will not absorb water. Specifically, one end of the high dielectric strength injection molding layer 4 is flush with the end sidewall of the integrated high voltage electrode 3 and does not extend to the end face of the integrated high voltage electrode 3. That is, this end of the high dielectric strength injection molding layer 4 is embedded in the end of the integrated high voltage electrode 3. The other end of the high dielectric strength injection molding layer 4 does not extend to the end face of the low voltage electrode 8 and is covered in the liquid silicone insulating layer 5 so as to seal the high dielectric strength injection molding layer 4 at this end through the liquid silicone insulating layer 5. In practical applications, one end of the liquid silicone insulating layer 5 is flush with the end face of the anti-corona pad 2, and the other end is flush with the end face of the low-voltage electrode 8, to ensure that the high dielectric strength injection molding layer 4 is completely encapsulated inside the liquid silicone insulating layer 5 and isolated from the outside. Graphite semiconductive silicone is sprayed on the outside of the liquid silicone insulating layer 5 to form a semiconductor shielding layer. The semiconductor shielding layer plays an important role in surge arresters, mainly used to improve the electric field distribution, prevent partial discharge, and improve the insulation performance and reliability of surge arresters.
[0033] Based on the aforementioned integrated high-voltage electrode 3 and the high-dielectric-strength injection molding layer 4 injected onto the outside of the integrated high-voltage electrode 3, the key to this structure is that one end of the integrated high-voltage electrode 3 connected to the valve plate assembly 7 is designed to be in a smooth and continuous necking shape, and the necking angle is 145° to 160°, more preferably 150° to 155°. This necking angle, combined with the design of the high-dielectric-strength injection molding layer 4, can homogenize the electric field and normalize the high-gradient electric field within the high-dielectric-strength injection molding layer.
[0034] It should be noted that the "necked" shape here can also be understood as a "reduced diameter" shape. The necking angle refers to the angle between the inclined surface and the horizontal plane in the radial cross-section of the reduced diameter portion, which is 153°. Extensive simulations and experimental verifications have shown that designing the integrated high-voltage electrode 3 using a necking method can homogenize the electric field at the high-voltage end of the integrated high-voltage electrode 3 and normalize the high-gradient electric field within the high-dielectric-strength injection-molded layer 4, thereby preventing partial discharge caused by the electric field strength exceeding the material properties. Simultaneously, due to the integrated injection molding, the structural strength between the integrated high-voltage electrode 3, the valve plate assembly 7, and the low-voltage electrode 8 in the surge arrester can be greatly improved, ensuring the reliability of transportation and storage, thus enhancing the overall structural reliability.
[0035] Based on the above, the integrated high-voltage electrode 3, valve plate group 7, and low-voltage electrode 8 at the tail end are formed by one injection molding of high dielectric strength injection molding layer 4 (PA66+30GF). At the same time, a liquid silicone insulating layer 5 is wrapped around the outside of the high dielectric strength injection molding layer 4, and graphite semi-conductive silicone is sprayed on the outside of the liquid silicone insulating layer 5. After secondary cross-linking, the surge arrester core is formed.
[0036] This utility model is not limited to the above-mentioned optional embodiments. Anyone can derive other forms of products under the guidance of this utility model. However, regardless of any changes made in its shape or structure, any technical solution that falls within the scope of the claims of this utility model shall be protected by this utility model.
Claims
1. A pluggable surge arrester, comprising a valve assembly (7) and a low-voltage electrode (8) connected to one end of the valve assembly (7), characterized in that, The surge arrester also includes: An integrated high-voltage electrode (3) is provided with an anti-corona pad (2) and a high-voltage contact (1) at one end, and the valve plate group (7) is connected to the other end. The outer walls of the integrated high voltage electrode (3), valve plate group (7) and low voltage electrode (8) are injection molded into one piece by the high dielectric strength injection layer (4); The end of the integrated high-voltage electrode (3) connected to the valve plate group (7) is in a smooth and continuous constricted shape.
2. The pluggable surge arrester according to claim 1, characterized in that, The surge arrester also includes: A liquid silicone insulating layer (5) is formed with an integrated high-voltage electrode (3), a valve plate assembly and a low-voltage electrode (8) to form a sealed cavity, and a high dielectric strength injection molding layer (4) is wrapped inside the sealed cavity.
3. The pluggable surge arrester according to claim 2, characterized in that, One end of the high dielectric strength injection molding layer (4) is flush with the end sidewall of the integrated high voltage electrode (3) and does not extend to the end face of the integrated high voltage electrode (3). The other end of the high dielectric strength injection molding layer (4) does not extend to the end face of the low voltage electrode (8) and is covered in the liquid silicone insulating layer (5).
4. The pluggable surge arrester according to claim 1, characterized in that, The integrated high-voltage electrode (3) is formed by combining a high-voltage conductive rod and a high-voltage electrode.
5. The pluggable surge arrester according to claim 2, characterized in that, The liquid silicone insulating layer (5) is coated with graphite semiconductive silicone to form a semiconductor shielding layer.
6. The pluggable surge arrester according to claim 3, characterized in that, One end of the liquid silicone insulating layer (5) is flush with the end face of the anti-corona pad (2), and the other end is flush with the end face of the low-voltage electrode (8).
7. The pluggable surge arrester according to claim 1, characterized in that, The constricted angle of the constricted neck is 145°~160°.
8. The pluggable surge arrester according to claim 1, characterized in that, The valve plate assembly (7) is a zinc oxide valve plate assembly.