Bionic self-suction type gas insulated switch equalizing ring

Abstract

This invention discloses a biomimetic self-priming gas-insulated switch equalizing ring, solving the technical problems of complex installation and poor voltage equalization effect of existing equalizing rings. The equalizing ring includes an outer shielding shell, an inner equalizing shielding ring, conductive adhesive, and a conductive transition bushing. The outer shielding shell is fitted and fastened to the bolt mounting area inside the gas-insulated switch cabinet where voltage equalization is to be achieved. The inner equalizing shielding ring is coaxially nested inside the outer shielding shell, forming a double-layered hierarchical shielding cavity structure. A main sealing ring and a secondary sealing ring are respectively set between the outer shielding shell and the bolt mounting plate, and between the inner equalizing shielding ring and the bolt mounting plate. The sealing assembly, together with the outer shielding shell, the inner equalizing shielding ring, and the bolt mounting plate, forms a double-layered sealed chamber. Self-priming fixation is achieved through the pressure difference between the high-pressure gas inside the cabinet and the double-layered sealed chamber, while the conductive adhesive forms an equipotential body with the bolts.

Description

Technical Field

[0001] This invention relates to a biomimetic self-priming gas-insulated switch equalizing ring, belonging to the field of gas-insulated switch equalizing technology. Background Technology

[0002] In recent years, with the development of new power systems and the continuous promotion and application of new energy power generation systems such as wind power and photovoltaics, gas-insulated circuit breakers (GECBs), as core electrical equipment in power systems that carry and interrupt current, have seen increasingly widespread applications. The industry's requirements for their breaking performance and operational stability have also been continuously increasing. When GECBs operate under high voltage and high current conditions, strong electric field concentration areas easily form at the bolted connections inside the equipment. This leads to severely uneven electric field distribution in these areas, resulting in phenomena such as corona discharge and surface flashover. Long-term operation will cause aging of the equipment's insulation components and a decline in insulation performance, seriously affecting not only the safety and reliability of the GECB itself but also threatening the stable operation of the entire power system, potentially causing large-scale power outages.

[0003] Existing voltage equalization schemes for bolted connections in gas-insulated circuit breakers generally suffer from problems such as complex installation and disassembly, poor voltage equalization effect, and poor adaptability. These issues make it difficult to meet the insulation and voltage equalization requirements of gas-insulated circuit breakers under high voltage and high current conditions, becoming a significant factor restricting the technological upgrade and application expansion of gas-insulated circuit breakers. For example, Chinese patent ZL202423268799.0 discloses a low partial discharge indoor high-voltage vacuum circuit breaker with an annular voltage equalization ring sandwiched between the stationary contact and the bolt at the rear end of the blade-type stationary contact. However, this voltage equalization ring needs to be placed between the base plate and the bolt before bolt installation. The installation and disassembly process requires the entire bolt to be disassembled and reassembled, which is cumbersome, time-consuming, and labor-intensive. Furthermore, the structural design of the voltage equalization ring still suffers from excessive electric field concentration at the bolted connection. This installation method also causes significant inconvenience for later maintenance of the equipment, reducing the maintenance-free nature and operational reliability of the gas-insulated circuit breaker. Summary of the Invention

[0004] The purpose of this invention is to provide a biomimetic self-priming gas-insulated switch equalizing ring, which solves at least one of the following problems in existing gas-insulated switches: severe electric field concentration at bolted connections, weak single-layer equalizing shielding effect, unreliable equipotential bonding, poor sealing, cumbersome installation and disassembly, and susceptibility to local optima in single optimization algorithms. This invention significantly simplifies the equalizing ring disassembly and assembly process, significantly improves insulation equalization effect, operational stability, and maintenance-free performance, and meets the insulation equalization requirements under high voltage and high current conditions.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A biomimetic self-priming gas-insulated switch equalizing ring, the equalizing ring comprising an outer shielding shell, an inner equalizing shielding ring, conductive adhesive, and a conductive transition bushing; The outer shielding shell is adapted to be fastened to the bolt mounting area inside the gas-insulated switch cabinet where pressure equalization is required, and the bolts in the bolt mounting area are fixed to the bolt mounting plate. The inner layer equalizing shielding inner ring is coaxially nested inside the outer shielding shell, forming an inner and outer double-layer hierarchical shielding cavity structure; A main sealing ring and a secondary sealing ring are respectively set between the outer shielding shell and the bolt mounting plate, and between the inner pressure equalizing shielding inner ring and the bolt mounting plate. The main sealing ring and the secondary sealing ring constitute a sealing assembly. The sealing assembly, together with the outer shielding shell, the inner pressure equalizing shielding inner ring, and the bolt mounting plate, forms a double-layer sealed chamber. Conductive adhesive is applied to the inner wall of the lower surface of the inner equalizing shielding ring and the inner side of the outer shielding shell. The inner side of the outer shielding shell and the upper surface of the inner equalizing shielding ring are connected as a whole by the conductive adhesive. The conductive transition bushing is coaxially fitted around each bolt in the bolt mounting area, and the upper part of the conductive transition bushing is embedded in the conductive adhesive coated on the lower surface of the inner pressure equalization shielding inner ring.

[0006] Furthermore, the area where the conductive adhesive is located on the inner wall of the lower surface of the inner ring of the inner equalizing shield is the bonding area, and the area of ​​the bonding area can cover all the locations of the bolts; The inner diameter of the conductive transition bushing matches the nut portion on the bolt.

[0007] Furthermore, the double-layer sealed chamber is engaged under normal pressure. After being fastened to the bolt mounting plate, the gas-insulated switch cabinet is filled with high-pressure gas. The double-layer sealed chamber and the high-pressure gas outside it are attracted and fixed to the bolt mounting plate by the pressure difference between the outer shield shell and the inner pressure equalizing shield ring. The bolt-bushing-conductive adhesive-inner ring-shell are then formed as a whole through the conductive transition bushing and conductive adhesive.

[0008] Furthermore, both the outer shielding shell and the inner equalizing shielding ring are streamlined variable curvature structures optimized by an optimization algorithm.

[0009] Furthermore, the optimization algorithm uses the key structural parameters of the outer shielding shell or the inner equal-pressure shielding ring as optimization design variables, and performs iterative optimization with the objectives of minimizing the maximum surface electric field intensity, minimizing the edge electric field non-uniformity coefficient, and minimizing the diameter.

[0010] Preferably, the optimization algorithm is a particle swarm optimization-genetic hybrid optimization algorithm, etc.

[0011] Furthermore, the outer shielding shell is made of a conductive metal material, such as aluminum alloy, copper, or stainless steel, and the outer surface is polished. The inner layer equalizing shielding ring is made of copper alloy. The main sealing ring and the secondary sealing ring are made of at least one of fluororubber or silicone rubber. The conductive transition bushing is a conductive copper bushing; The conductive adhesive is a room-temperature curing silver-based conductive adhesive.

[0012] Furthermore, the lower part of the outer shielding shell is provided with a first sealing groove for positioning and installing the main sealing ring, and the main sealing ring is interference-fitted into the first sealing groove at the lower part of the outer shielding shell; A second sealing groove is provided on the upper part of the secondary sealing ring to position and embed the inner pressure equalization shielding inner ring.

[0013] Furthermore, the outer shielding shell, the inner pressure equalizing shielding inner ring, the main sealing ring, and the secondary sealing ring can all be disassembled and installed independently. After disassembly, the conductive adhesive residue can be cleaned, and the main sealing ring and secondary sealing ring can be checked for damage or replaced with new main sealing rings and secondary sealing rings if damaged. The whole assembly can then be reused.

[0014] Furthermore, the outer shielding shell is generally circular in structure and has a curved side that bends downward and folds inward. The side is arc-shaped. The radius of the transition arc connecting the arc-shaped structure and the upper end face of the outer shielding shell is denoted as the upper edge fillet radius R1, and the radius of the transition arc folding inward at the lower end of the arc-shaped structure is denoted as the lower edge fillet radius R2. The cross-section of the inner layer equalizing shielding inner ring is a circular arc streamline shape, which protrudes to the side where the outer shielding shell is located.

[0015] Compared with existing technologies, the biomimetic self-priming gas-insulated switch equalizing ring of this invention combines the negative pressure self-priming of the lamprey's sucker structure with the characteristics of internal flexible connection. It achieves substantial structural improvements and performance leaps in terms of structural configuration, shielding method, fixing form, conductive connection, optimized algorithm, disassembly and maintenance, adaptation and reuse, and operational reliability. It has outstanding inventiveness and practical value. The specific beneficial effects are described in detail below: 1. This invention features a pioneering double-layer hierarchical shielding cavity structure, overcoming the limitations of traditional single-layer equipotential ring electric field shielding. Existing conventional equipotential rings are all single integral circular shell structures, relying solely on the outer curved surface for passive electric field shielding. This only provides simple shielding of the large-scale electric field outside the bolt, failing to address the layered conduction of the strong distorted electric field at the bolt head tip. Under high-voltage conditions, there are still obvious electric field concentration points, easily triggering corona discharge and surface flashover. This invention adds an independent inner equipotential shielding ring, forming a coaxial nested double-layer hierarchical shielding cavity structure with the outer shielding shell. Utilizing the annular buffer gap between the inner and outer rings, it achieves a hierarchical conduction mode for the distorted electric field: the inner equipotential shielding ring first-level convergence and buffering, and the outer shielding shell second-level equipotential diffusion. This gradually weakens the tip discharge effect from the spatial field strength distribution. Compared to traditional single-layer equipotential rings, it can completely eliminate the problem of local electric field accumulation at the bolt connection from a physical structural perspective, resulting in more complete insulation protection layers and stronger equipotential protection capabilities.

[0016] 2. This invention employs a composite equipotential structure of conductive transition bushing and conductive adhesive to address the shortcomings of traditional equalizing rings in potential connection. Existing equalizing rings are mostly simple rings directly attached to the bolt's outer wall, relying either on mechanical hard contact for conductivity (resulting in large contact gaps, unstable contact resistance, potential jumps, and localized heating) or simply applying conductive adhesive, failing to achieve full-area equipotential coupling between the bolt and the equalizing ring, providing only physical shielding without equipotential amplification. This invention adds a conductive transition bushing as an intermediate conductive connecting component, avoiding direct hard contact between the bolt and the ring, thus ensuring a smooth potential transition, reducing contact resistance, and preventing vibration-induced loosening. Simultaneously, a layered conductive adhesive coating ensures stable potential transfer between the bolt, bushing, inner ring, and outer shell. After curing, it forms an integrated, full-area equipotential structure encompassing the bolt, bushing, conductive adhesive, inner ring, and outer shell, eliminating electric field distortion caused by the bolt tip from an electrical mechanism perspective. The equalizing effect is upgraded from passive shielding to active equipotential amplification—a design logic completely absent in existing similar structures.

[0017] 3. The use of a combined main and auxiliary sealing ring assembly enhances the airtightness and operational stability of the bionic self-priming fixing system. Traditional self-priming equalizing rings only have a single sealing ring, resulting in a limited sealing path and low fault tolerance. They are susceptible to problems such as air leakage, negative pressure attenuation, and ring loosening and displacement due to fluctuations in internal air pressure, long-term equipment vibration, and slight flatness deviations of the mounting surface. Over long-term operation, the reliability of self-priming fixing decreases, and the equalizing position shifts, ultimately leading to the loss of equalizing function. This invention uses a combined sealing assembly consisting of a main sealing ring and an auxiliary sealing ring, forming two independent sealing lines. Together with an outer shielding shell, an inner equalizing shielding ring, and a bolt mounting plate, they form a double-layered sealed chamber. This provides high sealing redundancy and strong airtight pressure retention. Even under high-voltage gas-filled environments, long-term mechanical vibration, and alternating temperature conditions, it can maintain a negative pressure state in the chamber for extended periods, ensuring the equalizing ring remains accurately positioned and adsorbed, preventing displacement, loosening, or falling off. This significantly improves the long-term maintenance-free operation capability of the equipment.

[0018] 4. Introducing a particle swarm optimization-genetic hybrid optimization algorithm overcomes the inherent defects of traditional single simulation or algorithm. Most existing equalizing ring structures rely on empirical design or ordinary single electric field simulation for selection, with parameters determined by manual trial and error, lacking systematic multi-objective optimization; the few optimization methods that use single particle swarm or single neural network algorithms generally suffer from slow convergence speed, limited search range, easy getting trapped in local optima, and poor accuracy of coupled optimization of multiple key structural parameters. The designed ring contour, curvature, and wall thickness can only meet the basic use requirements and cannot accurately and uniformly distribute the bolt distortion electric field. This invention employs a particle swarm optimization-genetic hybrid optimization algorithm. First, a global, large-scale, and rapid search is performed using the particle swarm optimization algorithm to pinpoint the optimal parameter range. Then, the selection, crossover, and mutation mechanisms of the genetic algorithm are used for local fine-grained solutions, greatly increasing particle diversity and effectively escaping local optima. Simultaneously, multi-objective coupled iteration is used to minimize the maximum surface electric field intensity, minimize the edge electric field non-uniformity coefficient, and minimize the diameter. This precisely optimizes key structural parameters such as the outer shielding shell and the inner equalizing shielding ring, ensuring that the shape of the formed double-layer ring perfectly conforms to the electric field distribution around the bolt. The electric field homogenization effect is far superior to empirical design and single-algorithm optimization schemes, and the structural and electric field adaptability reaches the theoretical optimal level.

[0019] 5. The biomimetic negative pressure self-priming installation structure significantly reduces maintenance difficulty compared to traditional disassembly and assembly methods. Existing bolt-mounted equalizing rings mostly require pre-installation between the bolt and the mounting plate. Installation, inspection, and disassembly necessitate complete disassembly of the bolt assembly, a cumbersome and time-consuming process. Repeated disassembly and assembly can easily damage the bolt tightening torque and insulation structure, hindering the maintenance-free design of the equipment. Even some quick-disassembly equalizing rings rely on additional fasteners such as connectors, clips, and nuts, resulting in numerous parts and complex assembly logic. This invention utilizes the pressure difference between a double-layered sealed chamber and the high-pressure gas inside the cabinet to achieve pure negative pressure self-priming fixation. It requires no modification to the bolt installation state or any additional fasteners. Installation simply involves alignment and snapping; disassembly only requires depressurization and removal. A single person can quickly complete the operation, increasing disassembly and assembly efficiency several times over. Furthermore, it does not disturb the bolt tightening structure or damage the original assembly state of the equipment. It is particularly suitable for later inspection, replacement, and maintenance operations in the confined spaces of gas-insulated switches, adapting to the needs of on-site engineering applications.

[0020] 6. Modular, reusable structure reduces the total lifecycle cost of equipment. Existing integrated equalizing rings are mostly one-time assembly structures, prone to deformation, seal failure, and conductive layer damage after disassembly, making them unusable for reuse. Each maintenance requires replacement of the entire component, resulting in high maintenance consumable costs. This invention designs the outer shielding shell, inner equalizing shielding ring, and sealing components as independent, detachable modules. After disassembly, only simple cleaning of conductive adhesive residue and inspection for undamaged areas are required for continued use. Only the sealing component needs replacement when the sealing ring ages and breaks; the remaining metal ring components can be reused long-term, significantly reducing spare parts consumption and lowering the long-term economic cost of power equipment operation.

[0021] 7. Matching material and surface treatment design to suppress corona discharge. Ordinary equalizing rings use arbitrary material selection; if the shell surface is not treated, microscopic irregularities can easily cause localized field distortion, becoming the starting point for corona discharge. This invention uses a high-conductivity aluminum alloy, copper, or stainless steel for the outer shielding shell, and a high-conductivity copper alloy for the inner equalizing shielding ring, balancing conductivity and structural strength. The outer surface of the shell is mirror-polished to eliminate burrs and microscopic protrusions, simultaneously reducing the surface initiation field strength from both structural morphology and material properties, further suppressing corona generation and meeting the requirements for long-term safe operation at high voltage levels.

[0022] 8. Improved voltage equalization and field homogenization effects. Simulation comparisons under the same operating conditions show that the maximum electric field strength at bolted connections in existing conventional structures reaches as high as 4.35 kV / mm, with prominent electric field concentration. This invention, through double-layer shielding combined with conductive adhesive to form a gradient field homogenization and optimization using a particle swarm optimization-genetic hybrid algorithm, reduces the maximum electric field strength to 2.65 kV / mm under the same operating conditions. The field strength amplitude is significantly reduced, and the electric field distribution is smooth and uniform with no obvious distortion concentration points. This fundamentally reduces the risk of insulation aging, surface flashover, and internal breakdown, effectively extending the service life of gas-insulated switch components and ensuring the operational stability of the entire equipment and even the regional power grid.

[0023] In summary, this invention, based on the biomimetic structure of the lamprey's sucker, makes structural and fundamental improvements to the inherent defects of existing technologies in many aspects, including physical shielding structure, electrical equipotential connection, sealing and fixing method, optimization algorithm, disassembly and maintenance method, and economic value of reuse. It is not a simple change in shape or replacement of conventional materials, but has distinct substantive features and significant progress, and fully meets the criteria for judging patent inventiveness. Attached Figure Description

[0024] Figure 1 This is a three-dimensional structural schematic diagram of an embodiment of the biomimetic self-priming gas-insulated switch equalizing ring of the present invention.

[0025] Figure 2 An embodiment of the biomimetic self-priming gas-insulated switch equalizing ring of the present invention is as follows: Figure 1 A schematic diagram of a half-section structure passing through the center of the equalizing ring perpendicular to the line connecting the two bolts.

[0026] Figure 3 This is a partially enlarged schematic diagram of the outer shielding shell of an embodiment of the biomimetic self-priming gas-insulated switch equalizing ring of the present invention.

[0027] Figure 4 This is a partial structural schematic diagram of the secondary sealing ring according to an embodiment of the present invention.

[0028] Figure 5 This is an exploded structural diagram of one embodiment of the equalizing ring of the biomimetic self-priming gas-insulated switch of the present invention.

[0029] Figure 6 This is a flowchart illustrating the particle swarm optimization-genetic hybrid optimization algorithm in this invention.

[0030] In the diagram: 1. Outer shielding shell; 11. First sealing groove; 2. Inner pressure equalizing shielding inner ring; 3. Main sealing ring; 4. Conductive adhesive; 5. Conductive transition bushing; 6. Bolt; 7. Bolt mounting plate; 8. Secondary sealing ring; 81. Second sealing groove. Detailed Implementation

[0031] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit 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. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0032] This invention relates to a biomimetic self-priming gas-insulated switch equalizing ring (see...) Figure 1-5 The system includes an outer shielding shell 1, an inner equalizing shielding ring 2, conductive adhesive 4, and a conductive transition bushing 5. The outer shielding shell 1 is adapted to be fastened to the bolt mounting area inside the gas-insulated switch cabinet where equalization is required. The bolts in the bolt mounting area are fixed on the bolt mounting plate 7. The number of bolts in the bolt mounting area can be one, two, three, or even more. The inner equalizing shielding ring 2 is coaxially nested inside the outer shielding shell 1, forming a double-layer graded shielding cavity structure. A main sealing ring 3 and a secondary sealing ring 8 are respectively set between the outer shielding shell and the bolt mounting plate, and between the inner equalizing shielding ring 2 and the bolt mounting plate. The main sealing ring and the secondary sealing ring constitute a sealing assembly. The sealing assembly, together with the outer shielding shell, the inner equalizing shielding ring, and the bolt mounting plate, forms a double-layer sealed cavity.

[0033] Conductive adhesive 4 is applied to the inner wall of the lower surface of the inner equalizing shielding ring 2 and the inner side of the outer shielding shell 1. The area of ​​the conductive adhesive on the inner wall of the lower surface of the inner equalizing shielding ring 2 is the bonding area, and the area of ​​the bonding area can cover all the bolt locations. The inner side of the outer shielding shell 1 and the upper surface of the inner equalizing shielding ring 2 are connected as a whole by conductive adhesive. The upper part of the conductive transition bushing 5 is embedded in the conductive adhesive applied to the lower surface of the inner equalizing shielding ring 2. The conductive transition bushing 5 is coaxially sleeved on the outside of each bolt in the bolt mounting area; the bolt 6 passes through the bolt mounting plate 7 and is fixedly connected to the bolt mounting plate; the inner diameter of the conductive transition bushing 5 matches the nut part on the bolt; the conductive transition bushing 5 can be directly purchased commercially. The outer shielding shell 1 and the inner equalizing shielding ring 2 are fastened to the bolt mounting plate through a double-layer sealed chamber. During the fastening process, the conductive transition bushing 5 is embedded in the conductive adhesive at the corresponding position on the inner wall of the lower surface of the inner equalizing shielding ring 2. The double-layer sealed chamber is fastened under normal pressure. After fastening to the bolt mounting plate, the gas-insulated switch cabinet is filled with high-pressure gas, and the double-layer sealed chamber is in a high-pressure gas environment. The high-pressure gas outside the double-layer sealed chamber and the high-pressure gas outside the chamber attract and fix the outer shielding shell 1 and the inner equalizing shielding ring 2 to the bolt mounting plate 7 through the pressure difference. A bolt-bushing-conductive adhesive-inner ring-shell equipotential body is formed throughout the entire range via the conductive transition bushing 5 and the conductive adhesive 4.

[0034] Furthermore, both the outer shielding shell and the inner equalizing shielding ring are streamlined variable curvature structures iteratively optimized using a particle swarm optimization-genetic hybrid optimization algorithm. The objective functions are minimizing the maximum electric field intensity on the surface of the outer shielding shell, minimizing the electric field non-uniformity coefficient at the edge of the outer shielding shell, and minimizing the diameter of the outer shielding shell (here, the diameter at the position with the largest overall size of the outer shielding shell is used). The particle swarm optimization-genetic hybrid optimization algorithm iteratively optimizes key structural parameters such as the diameter and edge radius of the outer shielding shell, eliminating electric field concentration points around the bolts while ensuring a regular shape for easy manual handling and assembly. The inner equalizing shielding ring is also optimized using the same three objective functions: minimizing the maximum electric field intensity on the surface, minimizing the electric field non-uniformity coefficient at the edge, and minimizing the diameter.

[0035] Furthermore, the outer shielding shell 1 is made of a highly conductive metal material, preferably aluminum alloy, copper or stainless steel, and the outer surface is polished to reduce the probability of local field strength distortion and corona discharge caused by surface roughness; the lower part of the outer shielding shell 1 is provided with a first sealing groove 11 for positioning and installing the main sealing ring 3.

[0036] Furthermore, the inner equalizing shielding ring 2 is made of a highly conductive copper alloy, which can be the same as or different from the outer shell. The cross-section is a streamlined arc shape, which protrudes to the side where the outer shielding shell 1 is located, forming an annular electric field buffer gap with the outer shielding shell 1. The inner equalizing shielding ring and the outer shielding shell can perform first-level convergence buffering and second-level equalizing diffusion of the distorted electric field at the tip of the bolt 6, realizing double-layer graded electric field shielding, which greatly improves the electric field homogenization capability compared with the traditional single-layer equalizing ring.

[0037] Furthermore, both the main sealing ring 3 and the secondary sealing ring 8 are made of high-pressure resistant, high-elasticity fluororubber or silicone rubber. The main sealing ring 3 is interference-fitted into the first sealing groove 11 at the bottom of the outer shield shell 1, and the inner pressure equalizing shielding inner ring is embedded in the second sealing groove 81 at the top of the secondary sealing ring 8, forming double sealing protection inside and outside, ensuring the high airtightness of the double-layer sealed chamber, maintaining a long-term negative pressure self-priming state, and resisting the influence of air pressure fluctuations and equipment operation vibration inside the cabinet.

[0038] Furthermore, the conductive transition bushing 5 is a thin-walled conductive copper sleeve that is interference-fitted onto the outer surface of the bolt 6, serving as a potential buffer transition to avoid the bolt 6 directly contacting the equalizing ring, which could cause excessive contact resistance, localized heating, and potential jumps.

[0039] Furthermore, the conductive adhesive 4 can be a high-conductivity, room-temperature curing silver-based conductive adhesive. The conductive adhesive between the outer side of the inner equalizing shielding inner ring 2 and the inner side of the outer shielding shell 1 is defined as the outer conductive adhesive layer, and the conductive adhesive between the inner side of the inner equalizing shielding inner ring 2 and the conductive transition bushing is defined as the inner conductive adhesive layer. Compared with the resistance of the bolt directly contacting the inner equalizing shielding inner ring 2, the inner conductive adhesive layer ensures low-resistance connection between the bolt 6 and the conductive transition bushing 5, and the outer conductive adhesive layer realizes stable potential transfer between the inner equalizing shielding inner ring and the outer shielding shell. After curing, it not only achieves reliable electrical connection, but also has a moderate adhesive limiting effect, which helps to improve the overall structural stability.

[0040] Furthermore, the outer shielding shell 1, the inner pressure equalizing shielding inner ring 2, the main sealing ring 3, and the secondary sealing ring 8 can all be disassembled and disassembled independently. After disassembly, the conductive adhesive 4 residue can be cleaned, and the main sealing ring 3 and the secondary sealing ring 8 can be checked for damage or replaced with new main sealing ring 3 and secondary sealing ring 8 if damaged. The whole assembly can be reassembled and used repeatedly, with strong reusability and low maintenance cost.

[0041] This invention addresses the electric field characteristics of bolted connections in gas-insulated switchgear. The equalizing ring does not require a dedicated support structure for installation and does not rely on external standard parts for insertion / nut tightening, allowing for direct and rapid assembly to the bolt points. Furthermore, its self-priming fixing structure eliminates the need to disassemble fasteners during installation and disassembly, facilitating future maintenance. Stably fixed within the high-pressure gas environment inside the gas-insulated switchgear cabinet, the equalizing ring achieves equipotential bonding with the bolts using conductive adhesive, eliminating the problem of electric field concentration at the bolt head and providing excellent voltage equalization. Moreover, electric field simulation and optimization algorithms have been used to optimize the outer shielding shell and inner equalizing shielding ring in the bolt area, better adapting to the uniform electric field requirements under high voltage levels.

[0042] The contours, curvatures, and mating dimensions of the outer shielding shell and the inner equalizing shielding ring are optimized using a particle swarm optimization-genetic hybrid optimization algorithm to achieve a multi-level uniform distribution of the electric field at the bolt connection. A double-layer hierarchical shielding structure is formed by combining the outer shielding shell with the inner equalizing shielding ring. Multiple seals are constructed using sealing components. Combined with the pressure difference between the high-pressure gas inside the cabinet and the normal-pressure cavity inside the equalizing ring, the equalizing ring achieves self-priming fixation. By adding conductive transition bushings and conductive adhesive, a smooth and equipotential connection is achieved between the bolts, conductive transition bushings, the inner equalizing shielding ring, and the outer shielding shell, thereby weakening the phenomenon of electric field concentration on the bolt surface from the root.

[0043] The outer shielding shell 1 and the inner equalizing shielding ring of this invention are derived from the main structure of the lamprey's sucker. The installation and electrical connection methods are biomimeticly designed, combining negative pressure self-priming and internal flexible connection features to achieve biomimetic self-priming. This invention effectively eliminates electric field concentration at bolted connections, provides excellent voltage equalization, and eliminates the need for bolt removal during installation and disassembly, making operation convenient. It significantly improves the installation efficiency and operational reliability of gas-insulated switches and is suitable for gas-insulated switches operating under high voltage and high current conditions.

[0044] Example 1 like Figure 2 As shown, this embodiment provides a biomimetic self-priming gas-insulated switch equalizing ring, including an outer shielding shell 1, an inner equalizing shielding inner ring 2, conductive adhesive 4, and a conductive transition bushing 5.

[0045] This embodiment adapts to various gas-insulated switch bolt connection conditions based on different sizes. Taking a 24kV gas-insulated switch as an example, there are two bolts in the bolt installation area. The outer shield shell 1 has a circular structure with a downwardly curved and inwardly folded side. The side is an arc-shaped structure. The radius of the transition arc connecting the arc-shaped structure to the upper end face of the outer shield shell 1 is denoted as the upper edge fillet radius R1, and the radius of the transition arc folding inward at the lower end of the arc-shaped structure is denoted as the lower edge fillet radius R2. The outer shield shell 1 is made of aluminum alloy with a mirror-polished outer surface. The inner equalizing shielding inner ring 2 is made of copper and is coaxially nested inside the outer shield shell 1, forming a double-layer hierarchical shielding structure.

[0046] A main sealing ring 3 and a secondary sealing ring 8 are respectively provided between the outer shielding shell and the bolt mounting plate, and between the inner pressure equalizing shielding ring 2 and the bolt mounting plate. Both the main sealing ring 3 and the secondary sealing ring 8 are made of fluororubber and are respectively embedded in the bottom of the outer shielding shell 1 and the edge of the inner pressure equalizing shielding ring 2. The sealing assembly, the outer shielding shell 1, the inner pressure equalizing shielding ring 2, and the bolt mounting plate 7 enclose a double-layer sealed chamber.

[0047] The bolt mounting plate has two M8 stainless steel bolts and two conductive transition bushings. The conductive transition bushings 5 ​​are made of stainless steel and are interference-fitted onto the outer surface of the M8 stainless steel bolts. Conductive adhesive 4 is applied to the inner wall of the lower surface of the inner equalizing shielding ring 2 and the inner side of the outer shielding shell 1 at the corresponding bolt positions. The overall thickness of the conductive adhesive layer between the inner equalizing shielding ring 2 and the outer shielding shell 1 is 1.5mm, which can connect and support the inner equalizing shielding ring 2 and the outer shielding shell 1.

[0048] Bolt 6 passes through bolt mounting plate 7 and is fixed on the inside by nut. The outer shield shell 1 and the inner equalizing shield ring 2 are snapped together on the outside of bolt 6. The gas-insulated switch cabinet is filled with 0.15MPa high-pressure dry environmentally friendly gas. The double-layer sealed chamber is kept at normal pressure and is fixed by overall self-adsorption by gas pressure difference. After the conductive adhesive 4 is cured, bolt 6, conductive transition bushing 5, inner equalizing shield ring 2 and outer shield shell 1 form a reliable equipotential body.

[0049] Example 2 In this embodiment, based on Embodiment 1, the traditional single particle swarm optimization algorithm or single neural network algorithm is abandoned. Instead, a particle swarm-genetic hybrid optimization algorithm is adopted. This algorithm combines finite element electric field simulation to globally optimize the key structural parameters of the outer shielding shell 1 and the inner equal-pressure shielding inner ring 2. This increases particle diversity, helps escape local optima, and enhances the global search capability of the hybrid algorithm. The optimization process of the outer shielding shell 1 is described below as an example, with the specific steps as follows: Establish simulation model and optimization variables: Given the bolt spacing in the bolt installation area, build a simulation model of the bolt connection part of the gas-insulated switch. Select the outer shield shell diameter, upper edge fillet radius R1, and lower edge fillet radius R2 as optimization design variables, and set the boundary constraint range of each optimization design variable according to the actual working conditions.

[0050] Algorithm initialization: The particle size is set to 100. Each particle contains three key structural parameters: the diameter of the outer shield shell, the radius of the upper edge rounded corner R1, and the radius of the lower edge rounded corner R2. The relevant algorithm parameters are set as follows: inertia weight is 1.2, learning factor c1 is 1.5, c2 is 2, genetic crossover probability is 0.6, mutation probability is 0.01, and the maximum number of iterations is 200.

[0051] Construct a multi-objective function: The optimization objectives are to minimize the maximum electric field strength on the shell surface, minimize the non-uniformity coefficient of the electric field distribution at the shell edge, and minimize the shell diameter, while also considering the requirements for reducing field strength and equalizing voltage. The three objective functions are expressed by the following formula:

[0052] In the formula, E maxThe maximum electric field strength in the bolt mounting area. β The coefficient representing the non-uniformity of the electric field distribution at the edge of the shell. d The diameter of the outer shell; obj 1. obj 2. obj 3 represents three objective functions.

[0053] The fitness is calculated using a multi-objective function, whereby the fitness is: obj 1. obj 2. obj 3. The weighted sum of the three, with each weight coefficient being 1 / 3 in this embodiment.

[0054] Coupled simulation iterative optimization: Each particle, composed of three key structural parameters, is imported into the simulation model. The fitness of each particle is calculated. The particles are divided into two parts according to their fitness. It is determined whether the fitness is better than half of the particles. The particles are divided into a relatively better fitness part and a relatively worse fitness part. For particles with relatively good fitness, a crossover and mutation mechanism is introduced to perform a genetic algorithm for local fine-tuning. For particles with relatively poor fitness, a particle swarm optimization algorithm is used to perform a fast global search. The output particles of the genetic algorithm and the particle swarm optimization algorithm are merged, and then it is determined whether the maximum number of iterations has been reached. If the maximum number of iterations has not been reached, the particle fitness is recalculated and the next iteration is performed. The two-branch approach is used to overcome the shortcomings of the single particle swarm optimization algorithm, which is prone to getting trapped in local optima and has a slow convergence speed.

[0055] Output key structural parameters: When the maximum number of iterations is reached, the optimized key structural parameters are output. The outer shielding shell is then fabricated using the optimized key structural parameters to ensure the optimal electric field distribution.

[0056] In this embodiment, two M8 bolts with an 8mm spacing are installed on the bolt mounting plate. The optimized outer shielding shell has a diameter of 40mm, an upper edge fillet radius R1 of 3.5mm, and a lower edge fillet radius R2 of 1mm. A 24kV voltage is applied to the bolts. After electric field simulation testing, this embodiment uses double-layer shielding combined with conductive adhesive to form a gradient uniform field and a particle swarm-genetic hybrid optimization algorithm. The maximum electric field strength at the bolt connection is reduced from the original 4.35kV / mm to 2.65kV / mm. The electric field distribution is uniform with no local concentration points, effectively suppressing corona discharge and surface flashover. The equipment's operational stability and insulation reliability are greatly improved.

[0057] Example 3 The installation method of this embodiment includes the following steps: S1. Pretreatment: Use anhydrous ethanol to wipe and clean the bolt mounting area, bolt outer surface, and inner and outer walls of the conductive transition bushing on the bolt mounting plate to remove oil, dust and oxide layer, and let it air dry naturally. S2. Bushing assembly: The conductive transition bushing is interference-fitted and fixed to the outer wall of the bolt on the outside of the bolt mounting plate; S3. The sealing components are respectively assembled with the outer shielding shell and the inner pressure equalizing shielding ring: the main sealing ring is embedded in the first sealing groove 11 of the outer shielding shell, and the inner pressure equalizing shielding ring is snapped into the second sealing groove 81 of the auxiliary sealing ring. S4. Conductive adhesive coating: Conductive adhesive is applied in layers to the inner wall of the inner equalizing shielding inner ring and the conductive transition bushing on the opposite side, as well as to the designated area on the inner side of the outer shielding shell. The coating thickness is controlled to be uniform, without bubbles or missed areas. After the conductive adhesive cures, the upper end of the conductive transition bushing and the inner wall of the inner equalizing shielding inner ring, as well as the outer wall of the inner equalizing shielding inner ring and the outer shielding shell, are connected together by the conductive adhesive to form a reliable equipotential body. S5. Alignment and fastening: Align the assembled inner pressure equalizing shielding inner ring, conductive adhesive, sealing components, and outer shielding shell with the bolt mounting area of ​​the bolt mounting plate and fasten them together. The upper end of the conductive transition bushing is embedded in the conductive adhesive on the inner wall of the inner pressure equalizing shielding inner ring, so that the sealing components and the contact surfaces of the bolt mounting plate in all directions are in close contact, forming a double-layer sealed chamber. S6. Gas pressure adsorption curing: High-pressure gas is filled into the gas-insulated switch cabinet to 0.15MPa. The overall structure is self-adhesive and bonded by negative pressure using the air pressure difference. After the conductive adhesive has completely cured at room temperature, the installation is completed.

[0058] The accompanying drawings of the embodiments disclosed in this invention only involve structures relevant to the embodiments of this disclosure; other structures can be referred to in a general design.

[0059] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention. The specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments and features described in this specification.

[0060] Any aspects not covered in this invention are applicable to existing technologies.

Claims

1. A biomimetic self-priming gas-insulated switch equalizing ring, characterized in that, The equalizing ring includes an outer shielding shell, an inner equalizing shielding ring, conductive adhesive, and a conductive transition bushing. The outer shielding shell is adapted to be fastened to the bolt mounting area inside the gas-insulated switch cabinet where pressure equalization is required, and the bolts in the bolt mounting area are fixed to the bolt mounting plate. The inner layer equalizing shielding inner ring is coaxially nested inside the outer shielding shell, forming an inner and outer double-layer hierarchical shielding cavity structure; A main sealing ring and a secondary sealing ring are respectively set between the outer shielding shell and the bolt mounting plate, and between the inner pressure equalizing shielding inner ring and the bolt mounting plate. The main sealing ring and the secondary sealing ring constitute a sealing assembly. The sealing assembly, together with the outer shielding shell, the inner pressure equalizing shielding inner ring, and the bolt mounting plate, forms a double-layer sealed chamber. Conductive adhesive is applied to the inner wall of the lower surface of the inner equalizing shielding ring and the inner side of the outer shielding shell. The inner side of the outer shielding shell and the upper surface of the inner equalizing shielding ring are connected as a whole by the conductive adhesive. The conductive transition bushing is coaxially fitted around each bolt in the bolt mounting area, and the upper part of the conductive transition bushing is embedded in the conductive adhesive coated on the lower surface of the inner pressure equalization shielding inner ring.

2. The biomimetic self-priming gas-insulated switch equalizing ring according to claim 1, characterized in that, The area where the conductive adhesive is located on the inner wall of the lower surface of the inner layer equalizing shielding inner ring is the bonding area, and the area of ​​the bonding area can cover all the bolt locations. The inner diameter of the conductive transition bushing matches the nut portion on the bolt.

3. The biomimetic self-priming gas-insulated switch equalizing ring according to claim 1, characterized in that, The double-layer sealed chamber is under normal pressure. After being fastened to the bolt mounting plate, the gas-insulated switch cabinet is filled with high-pressure gas. The high-pressure gas outside the double-layer sealed chamber and the high-pressure gas outside the chamber attract and fix the outer shield shell and the inner equalizing shield ring to the bolt mounting plate through the pressure difference. Furthermore, through the conductive transition bushing and conductive adhesive, a bolt-bushing-conductive adhesive-inner ring-shell equipotential body is formed throughout the entire range.

4. The biomimetic self-priming gas-insulated switch equalizing ring according to claim 1, characterized in that, Both the outer shielding shell and the inner equalizing shielding ring are streamlined variable curvature structures optimized by an optimization algorithm.

5. The biomimetic self-priming gas-insulated switch equalizing ring according to claim 4, characterized in that, The optimization algorithm uses the key structural parameters of the outer shielding shell or the inner equal-pressure shielding ring as optimization design variables, and performs iterative optimization with the objectives of minimizing the maximum surface electric field intensity, minimizing the edge electric field non-uniformity coefficient, and minimizing the diameter; the optimization algorithm is a particle swarm-genetic hybrid optimization algorithm.

6. The biomimetic self-priming gas-insulated switch equalizing ring according to claim 1, characterized in that, The outer shielding shell is made of conductive metal material, such as at least one of aluminum alloy, copper or stainless steel, and the outer surface is polished. The inner layer equalizing shielding ring is made of copper alloy. The main sealing ring and the secondary sealing ring are made of at least one of fluororubber or silicone rubber. The conductive transition bushing is a conductive copper bushing; The conductive adhesive is a room-temperature curing silver-based conductive adhesive.

7. The biomimetic self-priming gas-insulated switch equalizing ring according to claim 1, characterized in that, The lower part of the outer shielding shell is provided with a first sealing groove for positioning and installing the main sealing ring. The main sealing ring is interference-fitted into the first sealing groove at the lower part of the outer shielding shell. A second sealing groove is provided on the upper part of the secondary sealing ring to position and embed the inner pressure equalization shielding inner ring.

8. The biomimetic self-priming gas-insulated switch equalizing ring according to claim 7, characterized in that, The outer shielding shell, the inner equalizing shielding ring, the main sealing ring, and the secondary sealing ring can all be disassembled and installed independently. After disassembly, the conductive adhesive residue can be cleaned, and the main sealing ring and secondary sealing ring can be checked for damage or replaced with new ones if damaged. The whole assembly can then be reused.

9. The biomimetic self-priming gas-insulated switch equalizing ring according to claim 1, characterized in that, The outer shielding shell is circular in shape and has curved sides that bend downwards and fold inwards. The cross-section of the inner layer equalizing shielding inner ring is a circular arc streamline shape, which protrudes to the side where the outer shielding shell is located.

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