A dual-trap device and method for improving the particle capture rate of gas-insulated equipment

Abstract

The application relates to a double-trap device and method for improving the particle capture rate of a gas insulated device, and the method comprises the following steps: constructing a double-arc geometric closed loop model to obtain a first gradually changing arc instantaneous curvature radius value and a second closing arc fixed curvature radius value; constructing a guide rod trap; assembling the guide rod trap outside a high-voltage conductor of the gas insulated device; and arranging a bending trap on a metal sealing outer cylinder of the gas insulated device; the guide rod trap completes end trajectory guidance of charged particles; the bending trap intercepts the guided particles to improve the overall particle capture rate of the gas insulated device. The root electric field is stably released and the end trajectory of the charged particles is guided by the guide rod trap, the guided particles are obtained, the guided particles are specially intercepted by the bending trap, the particle motion trajectory in the device is effectively regulated, the particle disorder drift phenomenon is reduced, and the overall particle capture rate of the gas insulated device is steadily improved.

Description

Technical Field

[0001] This application relates to the field of electrical equipment technology, and specifically to a dual-trap device and method for improving the particle capture rate of gas-insulated equipment. Background Technology

[0002] GIL / GIS equipment, with its superior insulation performance, large transmission capacity, and strong environmental adaptability, is widely used in high-voltage and ultra-high-voltage power transmission projects. During long-term operation, friction from the opening and closing of high-voltage contacts, conductor vibration and wear, and residual impurities from assembly will generate a large number of metal particles. These particles... Under the influence of an electric field, insulating gases will become polarized and charged, resulting in a high-frequency reciprocating bouncing phenomenon known as the "firefly phenomenon".

[0003] However, existing technologies have significant drawbacks: most current GIL / GIS particle capture technologies employ a single-shell bending trap structure, which has obvious technical limitations: First, a single trap lacks a pre-positioned particle guide and energy-consuming structure, resulting in highly discrete particle movement, chaotic landing point distribution, and low trap matching accuracy, with a traditional capture rate of only about 63.1%; Second, charged particles decay slowly under strong electric fields, making them prone to secondary bouncing and reverse escape, thus failing to achieve complete capture; Third, particles tend to accumulate around the basin-type insulator, causing local electric field distortion and corona discharge, which can lead to insulation degradation and significantly reduce equipment reliability over long-term operation; Fourth, traditional trap structures do not incorporate optimal electric field design, easily resulting in local electric field concentration, sacrificing equipment insulation margin, and posing safety hazards.

[0004] To address the problems of low capture efficiency, severe particle escape, poor insulation compatibility, and lack of graded capture and control in existing technologies, this invention proposes a dual-trap collaborative control method consisting of a guide rod front-mounted variable tilt angle trap and a shell-bent rear-mounted trap. Through precise electric field calibration, variable tilt angle structure optimization, particle trajectory orientation control, graded energy-consuming capture, and escape-prevention closed-loop control, the capture rate of metal particles is significantly improved, thus solving the potential insulation hazards of particles in GIL / GIS equipment from the source.

[0005] Therefore, this invention proposes a dual-trap device and method to improve the particle capture rate of gas-insulated equipment. Summary of the Invention

[0006] To overcome the shortcomings of the prior art, this application provides a dual-trap device and method for improving the particle capture rate of gas-insulated equipment, specifically adopting the following technical solution.

[0007] A dual-trap method for improving the particulate capture rate of gas-insulated equipment includes the following steps.

[0008] Obtain the total axial length of the trap; construct a double circular arc geometric closed-loop model, the input of which is the total axial length of the trap, and obtain the instantaneous curvature radius value of the first segment of the gradual circular arc and the fixed curvature radius value of the second segment of the converging circular arc.

[0009] A first trap is constructed based on the instantaneous radius of curvature of the first gradually changing arc and the fixed radius of curvature of the second converging arc. The instantaneous radius of curvature of the first gradually changing arc and the fixed radius of curvature of the second converging arc are different. The first trap is a guide rod trap.

[0010] The first trap is mounted on the outside of the high-voltage conductor of the gas-insulated equipment, and the second trap is placed on the metal-sealed outer cylinder of the gas-insulated equipment. The root electric field is slowed down by the first trap, and the trajectory of the charged particles is guided by the first trap to obtain the guided particles. The second trap is a bending trap.

[0011] The second trap intercepts the guided particles, thereby improving the overall particle capture rate of the gas insulation equipment.

[0012] The first trap and the second trap are not limited to the guide rod trap and bending trap structures disclosed in this embodiment. They can also adopt other equivalent trap structures with the same front electric field slow-release guidance and rear damping interception functions.

[0013] Through the above technical solution, a double-circular-arc geometric closed-loop model is constructed with the total axial length of the trap as input. The instantaneous curvature radius value of the first gradually changing circular arc and the fixed curvature radius value of the second converging circular arc are obtained. Based on the two types of curvature radii, the first trap is constructed and installed on the outside of the high-voltage conductor of the gas-insulated equipment. The second trap is deployed on the metal-sealed outer cylinder of the gas-insulated equipment. The root electric field slowing and the trajectory guidance of the charged particle ends can be stably completed through the first trap to obtain the guided particles. Then, the guided particles are specifically intercepted by the second trap, which effectively regulates the movement trajectory of particles inside the equipment, reduces the disorderly drift of particles, and steadily improves the overall particle capture rate of the gas-insulated equipment.

[0014] As an optional embodiment of the present invention, a first arc segment is formed based on the instantaneous radius of curvature of the first segment of the gradual arc; and a second arc segment is formed based on the fixed radius of curvature of the second segment of the closing arc.

[0015] The angle between the tangent of the second arc segment and the horizontal direction is 13.5° to 15.0°.

[0016] The above technical solution can match the optimal incident angle of particles, adapt to the guiding characteristics of the first trap's closing structure, effectively optimize the particle incident path, reduce the situation of particles sliding against the wall, deviating and escaping, ensure that particles can stably enter the trap capture area, and improve the stability and effectiveness of particle capture.

[0017] As an optional embodiment of the present invention, the first trap is coated with epoxy resin, and the second trap is coated with polyimide; the residual charge coefficient of the epoxy resin coating is less than or equal to 0.22, the residual charge coefficient of the polyimide coating is greater than or equal to 0.35, and the difference between the residual charge coefficient of the polyimide coating and the residual charge coefficient of the epoxy resin coating is greater than or equal to 0.13, so that a stable unidirectional transport potential gradient is formed between the first trap and the second trap.

[0018] The above technical solution can establish a stable unidirectional transport potential gradient between the first trap and the second trap, and realize the directional transport of particles by relying on the differentiated coating charge characteristics, avoid the backflow of particles, and ensure the orderly capture of particles in the dual traps.

[0019] As an optional embodiment of the present invention, the first trap adopts a composite cavity structure with continuously varying depths. The composite cavity is a radially recessed cavity that smoothly varies from shallow to deep along the incident direction of the particles. The radial recess depth of the radially recessed cavity varies from 10.0 mm to 30.0 mm.

[0020] Through the above technical solution, the first trap adopts a radially concave composite cavity structure with a smooth gradient from shallow to deep along the incident direction of the particles. The radial concavity depth of the radially concave cavity is in the range of 10.0mm to 30.0mm. The gradient cavity structure can adapt to incident particles of different sizes and kinetic energies, and adapt to the requirements of particle sedimentation, retention and locking in layers. It avoids the defect that a single-depth cavity cannot adapt to particles of all sizes, and improves the adaptability and capture capability of particles of different specifications.

[0021] As an optional embodiment of the present invention, the double circular arc geometric closed-loop model is as follows.

[0022] .

[0023] In the formula, x is the axial coordinate of the trap, and L is the total axial length of the trap; This is the instantaneous radius of curvature value of the first segment of the gradually changing circular arc; The radius of curvature of the second segment's closing arc is a fixed value. It is the local maximum electric field intensity on the surface of the trap. This is a preset dielectric insulation safety threshold.

[0024] Through the above technical solution, the instantaneous radius of curvature of the first gradually changing arc and the optimal fixed radius of curvature of the second converging arc are solved by using a double-circular-arc geometric closed-loop model. At the same time, the constraint verification is completed by relying on the local maximum electric field intensity on the trap surface and the preset dielectric insulation safety threshold. Iterative design of the double-circular-arc structure parameters can be realized, ensuring the rationality of the first trap arc surface shape and avoiding the problem of local electric field distortion in the trap. Under the premise of ensuring the insulation safety margin of the equipment, the optimal effect of electric field mitigation and trajectory guidance is achieved.

[0025] As an optional embodiment of the present invention, it further includes a dynamic adaptive calibration step for the pneumatic electric field, constructing a dynamic adaptive calibration model for the pneumatic electric field based on real-time data from the equipment. The air pressure undergoes adaptive correction, and the dynamic adaptive calibration model for the air pressure electric field is as follows.

[0026] In the formula, This is the dynamic pressure correction factor. Real-time equipment air pressure; The rated reference pressure, For low-voltage offset correction constant, For pressure attenuation coefficient, is the baseline safety lower limit coefficient; e is a natural constant.

[0027] Using the above technical solutions, a dynamic adaptive calibration model of the pneumatic electric field is constructed, based on real-time equipment operation. The pressure adaptive correction relies on the synergistic effect of the low-pressure offset correction constant, pressure attenuation coefficient, and reference safety lower limit coefficient in the model. It can adapt to the equipment's pressure fluctuation conditions in real time, dynamically correct the electric field and particle capture parameters, and offset the influence of pressure changes on the trap electric field characteristics and particle motion state, thus ensuring the stability of particle capture performance under variable pressure conditions.

[0028] As an optional solution of the present invention, it also includes a dual-trap hierarchical collaborative closed-loop anti-escape control step, specifically including: constructing a dual-level series closed-loop anti-escape capture system of primary in-situ initial suppression and secondary final capture locking, completing the primary kinetic energy dissipation and preliminary capture of particles through the first trap, and then performing secondary damping locking capture of residual kinetic energy particles through the second trap; and constraining the final radial rebound velocity of particles after primary in-situ initial suppression and secondary final capture locking to below 0.3 m / s.

[0029] The above technical solution constructs a two-stage series closed-loop anti-escape capture system consisting of a first-stage in-situ initial suppression and a second-stage final capture and locking mechanism. The first trap dissipates the initial kinetic energy of the particles and performs preliminary capture. The second trap then performs secondary damping and locking capture of the particles with residual kinetic energy. At the same time, the final radial rebound velocity of the particles is constrained to below 0.3 m / s. This system can dissipate the kinetic energy of the particles step by step, effectively suppressing particle rebound, drift, and escape phenomena, achieving closed-loop locking capture of the particles, and significantly reducing the probability of particle escape.

[0030] As an optional solution of the present invention, the actual cumulative operating time of the gas-insulated equipment is collected in real time, and the aging performance of the guide rod trap is compensated based on the actual cumulative operating time; the aging performance of the bending trap is compensated based on the actual cumulative operating time.

[0031] By using the above technical solution, the actual cumulative operating time of the gas-insulated equipment is collected in real time, and the aging performance of the guide rod trap and the bending trap is compensated accordingly based on the actual cumulative operating time. This can adapt to the long-term aging and deterioration characteristics of the coating of the two types of traps in real time, compensate for the performance degradation of the coating caused by long-term operation of the equipment, continuously maintain the differentiated transport characteristics and capture performance of the two traps, and ensure the stable particle capture effect throughout the entire life cycle of the equipment.

[0032] The present invention provides a dual-trap method for improving the particle capture rate of gas-insulated equipment, comprising a basin-type insulator, a high-voltage conductor, a first trap, a second trap, and a metal-sealed outer cylinder.

[0033] A basin-type insulator is fixedly assembled inside the metal-sealed outer cylinder, and a high-voltage conductor is fixedly inserted through the center of the basin-type insulator; a first trap is fixedly installed inside the metal-sealed outer cylinder and outside the high-voltage conductor.

[0034] The first trap has two symmetrically arranged guide rod trap opening structures; the first trap as a whole adopts a non-uniform curvature double arc gradient curved surface shape; the inner side of the metal sealed outer cylinder is fixedly provided with a second trap, which is composed of multiple sets of bent baffles evenly arranged to form a single-slot grid buffer structure.

[0035] The above technical solution enables precise assembly and stable layout of dual traps. Relying on the curved guide structure of the first trap and the grid buffer interception structure of the second trap, a hierarchical capture structure system is formed, which has strong structural adaptability and good interception and buffering effect.

[0036] As an optional embodiment of the present invention, the first trap adopts an integrated conductive metal structure, and the first trap is sleeved and installed on the high voltage conductor on the convex side of the basin insulator.

[0037] By using the above technical solution, the first trap is set as an integrated conductive metal structure and sleeved on the high voltage conductor on the convex side of the basin insulator. This ensures the integrity and conductivity stability of the first trap structure, with precise assembly and firm fixation. It can stably achieve root electric field mitigation and particle trajectory guidance, avoid performance failure caused by trap assembly misalignment and structural loosening, and improve the overall reliability and structural stability of the device.

[0038] The technical solution of this application has achieved the following beneficial effects.

[0039] A double-circular-arc geometric closed-loop model is constructed with the total axial length of the trap as input. The instantaneous radius of curvature of the first gradually changing arc and the fixed radius of curvature of the second converging arc are obtained. Based on the two types of radii of curvature, a guide rod trap with non-uniform curvature double circular arc is constructed. The guide rod trap is assembled on the outside of the high-voltage conductor of the gas-insulated equipment, and the bending trap is placed on the metal sealed outer cylinder of the gas-insulated equipment. The root electric field is released stably and the trajectory of the charged particles is guided by the guide rod trap. The guided particles are then intercepted by the bending trap. This effectively regulates the movement trajectory of particles inside the equipment, reduces the disorderly drift of particles, and steadily improves the overall particle capture rate of the gas-insulated equipment. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of a dual-trap device for improving the particle capture rate of gas-insulated equipment in an embodiment of this application.

[0041] Figure 2 This is a schematic diagram of the guide rod trap structure of the dual trap device for improving the particle capture rate of gas-insulated equipment in the embodiments of this application.

[0042] Figure 3 This is a schematic diagram of a dual-trap device for improving the particle capture rate of gas-insulated equipment in an embodiment of this application, which drives away particles and suppresses firefly movement.

[0043] Figure 4 This is a schematic diagram of the particle trajectory under the action of bending traps in the dual-trap device for improving the particle capture rate of gas insulation equipment in the embodiments of this application.

[0044] Figure 5 This is a schematic diagram of the particle landing point of the dual-trap device for improving the particle capture rate of gas-insulated equipment in the embodiments of this application.

[0045] Reference numerals: 1. Basin insulator; 2. High-voltage conductor; 3. Guide rod trap; 4. Bending trap; 5. Guide rod trap opening structure; 6. Metal-sealed outer cylinder. Detailed Implementation

[0046] The present application will now be further described with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application and should not be construed as limiting the scope of protection of the present application. It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of the present application.

[0047] like Figure 1 As shown, the present invention discloses a dual-trap device for improving the particle capture rate of gas-insulated equipment, including a basin-type insulator 1, a high-voltage conductor 2, a guide rod trap 3, a bending trap 4, and a metal-sealed outer cylinder 6. The components are arranged in a coordinated manner to construct a complete escape-free capture path for particle directional driving, graded flow guidance, energy-consuming sedimentation, and closed-loop locking.

[0048] The metal-sealed outer cylinder 6 is internally fitted with a basin-type insulator 1. A high-voltage conductor 2 is fixedly inserted through the center of the basin-type insulator 1. The basin-type insulator 1 serves as the overall installation reference, achieving insulation isolation and rigid support between the high-voltage conductor and the cylinder structure.

[0049] Inside the metal-sealed outer cylinder 6 and outside the high-voltage conductor 2, a guide rod trap 3 is fixedly sleeved and installed. The guide rod trap 3 is an integrated conductive metal structure, and it is arranged in equipotential contact with the high-voltage conductor 2. Two guide rod trap opening structures 5 are symmetrically arranged on the guide rod trap 3. The guide rod trap 3 adopts a non-uniform curvature double-arc gradient curved surface shape. The guide rod trap 3 is set with an optimal particle guiding angle of 14.17°. Inside the guide rod trap 3, a 10.0~30.0mm deep and shallow graded composite dust collection cavity is formed. The guide rod trap opening structure 5 is an ingress channel optimized by the flow field and electric field, used for angle correction, trajectory convergence, and initial energy dissipation sedimentation of metal particles with a particle size of 5.0~200.0μm. The high-voltage conductor 2 is the core current-carrying component inside the GIL / GIS, and the guide rod trap 3 is sleeved and installed on the high-voltage conductor 2.

[0050] A bending trap 4 is fixedly installed on the inner side of the metal sealed outer cylinder 6. The bending trap 4 is composed of multiple sets of bending baffles evenly arranged to form a single-slot grid buffer structure. The bending trap 4 is arranged in the central area of ​​the particle concentration landing point after the guide rod trap 3 is controlled. The bending trap 4 and the guide rod trap 3 form a high-low position dual trap cooperative structure of high-position pre-drive initial capture and low-position post-damping final capture.

[0051] Among them, the surface of the guide rod trap 3 is coated with a low residual coefficient epoxy resin film, and the residual charge coefficient of the epoxy resin film is... ≤0.22; Bending Trap 4 surface is coated with a high residual coefficient polyimide film, the residual charge coefficient of the polyimide film is... ≥0.35; the difference in residual charge coefficient between the two coatings satisfies - With a potential of ≥ 0.13, a stable unidirectional potential transport gradient is formed through a double-trap differentiated residual coating, thereby constructing an irreversible particle directional migration channel.

[0052] The guide rod trap 3 serves as the primary control and capture unit, used to achieve in-situ sedimentation of particles, dissipation of firefly kinetic energy, and correction of directional trajectory. The bending trap 4 serves as the secondary locking and capture unit. The guide rod trap 3 is the pre-trapping trap, and the bending trap 4 is the post-trapping trap. By dissipating residual kinetic energy through multiple layers of grids, the rebound speed of particles is constrained to within 0.3 m / s, achieving permanent locking to prevent escape.

[0053] Furthermore, the guide rod trap 3 adopts an integrated conductive metal structure, using aluminum alloy or copper alloy materials and controlling the surface roughness Ra≤0.6μm. The guide rod trap 3 is sleeved and installed on the high voltage conductor on the convex side of the basin insulator.

[0054] The bending trap adopts a bending baffle-type single-slot grid structure, which is placed at the center of the particle concentration point. The entrance of the bending trap is precisely matched with the incident direction of the particles.

[0055] The bending trap 4 of the present invention adopts the grid bending trap structure of the existing patent CN121584484A, which is a mature particle damping locking structure. The present invention does not improve its structure, but only achieves closed-loop capture of particles by matching and deploying it with the guide rod trap 3 and cooperating with differentiated coating.

[0056] The guide rod trap 3 includes an integrated metal trap body. The outer side of the trap body is connected with a first arc segment and a second arc segment. The first arc segment is a gradually changing arc structure with a continuously and smoothly changing radius of curvature, and the second arc segment is a closed arc structure with a fixed radius of curvature. The trap body has a gradually changing composite cavity structure inside, and the trap body has symmetrical guide rod trap opening structures.

[0057] This invention discloses a dual-trap method for improving the particle capture rate of gas-insulated equipment, comprising the following steps.

[0058] Step S1, Coaxial cavity reference parameter locking and global universal electric field optimal range calibration: This invention uses the standard commercial GIL structure as the calibration reference. The GIS equipment scales the structural parameters proportionally according to its own cylinder size, and keeps the electric field ratio, tilt angle parameter and charge residual coefficient difference unchanged throughout the process, ensuring that the capture mechanism and insulation performance are equivalent and consistent.

[0059] Setting reference structural parameters: high voltage conductor radius Inner radius of the equipment casing Establish a safety constraint system for the electric field of the coaxial cavity and control the radius ratio range between the outer shell and the trap shield.

[0060] .

[0061] Based on the geometric relationship of the trap protrusion height: .

[0062] Iteration yields the safe range for the effective protrusion height of the trap: This range can ensure that the equipment insulation margin is not less than 95%, with no local electric field distortion, and is compatible with full-size coaxial cavities of GIL / GIS.

[0063] The radius of the high-voltage conductor is taken from the structural setting of commercial standard ultra-high voltage GIL equipment. The inner radius of the equipment's metal casing is taken from the structural setting of commercial standard UHV GIL equipment. Let be the outer radius of the trap shield, and let be the variable to be solved in the simulation iteration. The value constraints are obtained by the simulation test of the optimal uniformity of the electric field in the coaxial cavity. The effective protrusion height of the trap is a structurally derived variable, calculated from the difference in radius between the shield and the guide rod.

[0064] Step S2, Non-uniform curvature double circular arc tilt angle trap: The present invention adopts a non-uniform curvature double circular arc gradient composite trap structure, which is different from the traditional single circular arc and flat plate structure. Through the seamless connection of two segments of differentiated curvature circular arcs, the dual optimal adaptation of electric field slow release and particle directional guidance is achieved, which is adapted to the dynamic characteristics of particles with a full range of particle size from 5.0 to 200.0 μm inside GIL / GIS.

[0065] S3. Dynamic Adaptive Calibration of Pressure Electric Field: Construct a dynamic adaptive calibration model for pressure electric field, perform adaptive correction of 0.4~0.6MPa across all pressures, adapt to different rated pressure conditions of GIL / GIS. The benchmark value is only for calibration reference, and the model has the ability to achieve adaptive convergence across the entire domain.

[0066] S4. Multi-condition insulation simulation full-domain verification: Complete full-domain electric field scanning under combined conditions of air pressure fluctuation, DC rated voltage, and lightning impulse, and determine the maximum electric field strength of the equipment across the entire domain. ,satisfy Insulation meets national standard thresholds; there is no localized field strength concentration, no dead zones of electric field distortion, and no risk of insulation breakdown throughout the entire process. Specifically, the double-arc trap cavity of the high-voltage conductor-side front-mounted guide rod trap can stably maintain a near-zero electric field environment. Relying on the electric field mitigation advantage of the gradually changing arc passivation structure, it can ensure the stability of the internal electric field of the cavity without drastic fluctuations even under multiple complex extreme operating conditions, continuously providing a safe operating environment for particle kinetic energy dissipation and sedimentation locking. This invention, through multi-dimensional full-domain simulation verification, differs from the limitations of traditional traps that only verify a single rated operating condition. It comprehensively verifies the insulation safety and particle capture stability of the structure under complex operating conditions such as air pressure deviation, rated energized operation, and transient lightning impact, achieving compliance with both insulation safety and particle energy dissipation technical indicators. It can stably adapt to all normal and fluctuating operating conditions of GIL / GIS equipment.

[0067] S5. Particle trajectory control and post-trap positioning: By comparing benchmark and optimized operating conditions, the migration law of particle trajectory is obtained, and the targeted and precise installation of post-bending traps is achieved, solving the problems of traditional traps' experience-based layout, low matching degree, and large capture blind zone.

[0068] S6. Dual-trap hierarchical collaborative closed-loop escape prevention control: Construct a dual-level collaborative system of primary in-situ initial suppression and secondary final capture and locking.

[0069] S7. Scene-specific array deployment: The collaborative capture mechanism of this invention is universally compatible with GIL / GIS, but the structural deployment method is designed according to the differences in equipment structure.

[0070] Step S8: Long-term stability monitoring and verification: Build a GIL / GIS full-condition test platform to cover all scenarios such as rated load, air pressure fluctuation, voltage surge, and temperature drift, and conduct long-term operation monitoring of the dual-trap collaborative system.

[0071] Example 1.

[0072] This embodiment 1 discloses a dual-trap method for improving the particle capture rate of gas-insulated equipment, wherein step S2 includes the following steps.

[0073] S21. Structural parameter optimization: Complete multi-objective simulation iterations within the safe height range to lock in the optimal structural parameters: total length of the trap axis. Maximum protrusion height Front opening height This parameter can control the surface electric field non-uniformity coefficient of the guide rod trap to within 1.03, balancing insulation safety and dust collection volume, and is applicable to both GIL and GIS.

[0074] S22. Construct a double-circular-arc geometric closed-loop model for guide rod trap 3: Construct a double-circular-arc geometric closed-loop model to achieve root electric field mitigation and precise end guidance. The double-circular-arc geometric closed-loop model is as follows.

[0075] .

[0076] In the formula, x is the axial coordinate of the trap, with a value of 0 ≤ x ≤ L, and L is the total axial length of the trap; The instantaneous radius of curvature of the first segment of the gradual arc of the guide rod trap is a binary gradual function that simultaneously relates the axial position x and the total axial length L. It changes continuously and smoothly along the trap axis, which can realize the gradual release of the electric field at the root of the trap. The fixed radius of curvature of the second segment's converging arc, i.e., the optimal fixed radius of curvature of the second segment's converging arc, is a linear function that depends only on the total axial length L of the trap and is independent of the axial position x. It changes linearly and adaptively with the total axial length L. This relationship is obtained through iterative fitting of electric field simulations under multiple dimensional conditions and is satisfied throughout the entire process. The dielectric insulation safety threshold constraint of 24kV / mm allows for adaptation to different guide rod trap sizes. In this embodiment, the total axial length of the trap is limited to L=80mm. Optimal curvature is obtained by substituting into the relational formula and performing simulation verification. =39.6mm, this value matches the optimal electric field constraint condition, ensuring a smooth transition between the two arc segments, without structural sharp corners or electric field distortion, maximizing the mitigation of end field strength and unifying the particle guidance trajectory. It is the local maximum electric field intensity on the surface of the trap. These are the static verification values ​​from the simulation during the structural parameter iteration process. They are constraints in the product design finalization stage and not real-time monitoring variables during equipment operation. After the structure is finalized, the electric field distribution on the trap surface is fixed, and there is no need for real-time monitoring of the electric field parameters. It can maintain long-term insulation, safety, and stable operation. For preset Dielectric insulation safety threshold; in this embodiment, The value is .

[0077] This application uses multi-objective iterative simulation and particle dynamics experiments to perform global optimization of the guide angle of the second-segment converging arc, limiting the tangent and horizontal inclination angle of the second-segment converging arc to the range of 13.5° to 15.0°. When the inclination angle is below 13.5°, the overall incident angle of the particles is too small, which easily leads to wall slippage, poor trajectory convergence, and a large number of particles falling into the ineffective escape zone, resulting in a significant decrease in the effective capture ratio. When the inclination angle is above 15.0°, the trap opening is too steep, which will cause excessive particle collision rebound kinetic energy, increase the radial escape probability, and easily cause a small distortion of the local electric field at the trap opening, reducing the insulation safety margin. Therefore, this application limits the optimal tilt angle of the converging arc to 13.5° to 15.0°, and converges to obtain the globally unique optimal solution of 14.17°. This angle can stably narrow the incident angle of the particles to the effective capture range of 0° to 35°, maximally suppressing particle slippage, drift and rebound escape, and taking into account both electric field insulation safety and particle guidance and capture efficiency.

[0078] Reference Figure 2 , Figure 3 , Figure 4 and Figure 5 The structure adopts a double-arc smooth transition. The first arc segment extends from the installation starting position a to the maximum protrusion height position b, and the second arc segment extends from the maximum protrusion height position b to the front opening position c. The tangent of the second arc segment makes an angle θ=14.17° with the horizontal direction, ensuring that the particle ingress angle is concentrated between 0° and 35°, avoiding direct escape due to a small ingress angle. The effective depth of the front opening is 10.0~30.0mm, ensuring that the particles falling into the contact are not easily stirred up again, achieving in-situ collection.

[0079] S23. Construct a self-consistent solution model for the optimal tilt angle: Establish a dual-objective optimization solution system that maximizes effective incident and minimizes field strength constraints, solve the globally optimal guiding tilt angle of the trap closing structure, solve the problem of particle adhesion and ineffective escape from the mechanism, and solve the unique globally optimal solution. The self-consistent solution model for the optimal tilt angle is as follows.

[0080] .

[0081] In the formula, The globally optimal steering angle is the unique convergent analytical solution of the dual-objective optimization model. The number of effective particles with an incident angle greater than 15° is the number of simulation statistical outputs. Input the total number of particles for the simulation; Let be the maximum electric field intensity on the surface of the guide rod trap at the corresponding tilt angle, and be the quantity to be solved in the electric field simulation. for The dielectric insulation safety threshold is obtained by testing and calibration according to the national standard GB / T 11022. These are constraints. This invention uses an inclination angle iteration range of 0° to 45° and a critical angle of 15° for effective particle incidence. Through global iterative solution, a dual-objective self-consistent optimization is achieved, yielding a unique convergent global optimal solution. The optimal inclination angle between the tangent of the second segment's converging arc and the horizontal direction is limited to 14.17°. This angle is a dimensionless, universally optimal angle suitable for GIL / GIS coaxial cavities, independent of the equipment's cylinder size. It can force the particle incidence angle to converge to the effective capture range of 0° to 35°, increasing the effective particle incidence rate to over 60%, significantly reducing the probability of particle wall slippage and disordered escape, and providing stable particle trajectory input conditions for dual-trap hierarchical capture.

[0082] S24. Guide Rod Trap for Layered Particle Capture and Airflow Entrainment Suppression: The guide rod trap of this invention adopts a continuously varying depth composite cavity structure of 10.0~30.0mm. The radial depth of the dust collection cavity of the guide rod trap is 10.0~30.0mm. The cavity smoothly transitions from a shallow area of ​​10.0mm to a deep area of ​​30.0mm along the particle incident direction, forming a gradient composite cavity structure to achieve layered capture of particles of all sizes. Relying on a smooth transition shape with non-uniform curvature double arcs, a gradient cavity space is formed from front to back and from shallow to deep, overcoming the shortcomings of traditional single-depth traps that cannot adapt to particles of all sizes, achieving precise layered capture and airflow entrainment suppression of metal particles of all sizes from 5.0~200.0μm. The gradient cavity is layered along the incident particle motion direction to match the kinetic energy characteristics and suspension laws of particles of different sizes. The specific layered capture mechanism is as follows: First, there is a shallow settling zone with a cavity depth range of 10.0~15.0 mm. For ultrafine lightweight particles of 5.0~50.0 μm, this shallow space has a gentle flow field and uniform electric field shielding effect, which can effectively isolate them. The system employs three main mechanisms: First, the airflow turbulence and entrainment effect weakens the lifting and suspending effect of airflow disturbance on small particles, enabling them to settle silently without disturbance and preventing secondary suspension and escape from the source. Second, the mid-layer retention zone, with a cavity depth of 15.0~22.0mm, is designed for medium-sized particles (50.0~120.0μm). This zone combines electric field mitigation with spatial confinement, stably retaining medium-sized particles with moderate incident kinetic energy and continuously dissipating residual kinetic energy to prevent them from bouncing and drifting. Third, the deep locking zone, with a cavity depth of 22.0~30.0mm, is designed for large-mass, large-size particles (120.0~200.0μm). The deep cavity forms a mechanically confined and locked space, and combined with a near-zero electric field environment, it completely dissipates the residual kinetic energy of particle impact, achieving permanent mechanical locking of large-size particles and preventing them from rebounding and escaping. Meanwhile, through the flow field optimization design of the double-circular-arc cavity structure, the entire interior of the trap cavity is optimized. The airflow disturbance velocity is strictly controlled within 0.15m / s, eliminating local airflow eddies and turbulence, and completely solving the industry problem of severe airflow disturbance and easy entrainment and lifting of small particles by airflow in traditional trap cavities, achieving the effect of stratified capture, stable storage and anti-escape of particles of all sizes.

[0083] S25. Differentiated Coated Unidirectional Transport: The pre-trap-guide rod trap 3 uses a low residual pressure epoxy resin coating, with a low residual charge coefficient. The post-trapping trap-bending trap 4 uses a high residual pressure polyimide coating, with a high residual charge coefficient. Fixed residual difference This forms a stable unidirectional transport potential gradient.

[0084] .

[0085] In the formula, The residual charge coefficient of epoxy resin coating, The residual charge coefficient of the polyimide coating is the measured value of the material under charged aging test. is the potential difference for directional transport of particles between the two traps, and is the output of the model calculation; for Gas dielectric correction constant, For operating conditions of 0.4~0.6MPa The correction constant for fitting the dielectric properties of the dielectric is determined by dielectric property tests. Let be the local equivalent electric field intensity inside the trap cavity, and be the solution quantity for multiphysics simulation.

[0086] This enables irreversible directional migration of particles from the guide rod trap to the rear trap, thus preventing disordered drift from a mechanistic perspective.

[0087] S26. Near-zero electric field quantitative energy dissipation to suppress fireflies: The guide rod trap 3-cavity forms a shielded near-zero electric field region, quantitatively constraining the field strength. Particle residence time The kinetic energy decay of the particles satisfies the condition.

[0088] .

[0089] In the formula, is the electric field strength inside the trap cavity, and is the quantitative constraint threshold for simulation monitoring; The residence time within the particle cavity; The initial kinetic energy of the incident particle is calculated from the particle size, field strength, and force formula. The near-zero electric field particle kinetic energy dissipation coefficient is a unique constant obtained by fitting and converging multiple sets of particle kinetic energy decay experiments. Let t be the remaining kinetic energy of the particle. Within 30ms, the residual kinetic energy of the particle decays to less than 5% of its initial value, thus blocking the energy source for the firefly's bouncing.

[0090] S27. Constructing an Adaptive Compensation Model for Coating Aging: This invention sets up an adaptive compensation mechanism for the aging of the double-trap coating throughout its entire life cycle, establishes a model for the decay of the residual charge coefficient throughout the entire life cycle, and compensates in real time for the aging performance degradation caused by the long-term operation of the two types of trap coatings, ensuring the long-term stability of the differentiated potential transport gradient of the double traps. The adaptive compensation model for coating aging is as follows.

[0091] In the formula, This represents the real-time residual charge coefficient corresponding to the runtime t. The initial residual charge coefficient of the coating is the value set during the material's factory charge test. The aging degradation constant of the material is obtained by fitting and calibration through high and low temperature cycling and long-term accelerated aging tests with electrical charge; the aging degradation constant of epoxy resin. aging degradation constant of polyimide Maintain throughout. An effective threshold ensures stable transport performance throughout the entire lifecycle of GIL / GIS.

[0092] The actual cumulative operating time of the gas-insulated equipment is collected in real time by the equipment monitoring system. In this model, the only real-time dynamically collected variable is the actual cumulative operating time t of the gas-insulated equipment, which is collected and updated in real time by the equipment's supporting monitoring system. All other parameters are fixed parameters calibrated at the factory and do not require online collection. By acquiring the cumulative operating time of the equipment in real time, the real-time residual charge coefficients of the two types of coatings are dynamically corrected, maintaining the difference in residual charge coefficients between polyimide coating and epoxy resin coating at no less than 0.13 throughout the process. This effectively avoids the problem of unidirectional transport potential gradient decay and failure caused by coating aging and ensures the continuous stability of unidirectional particle transport and graded capture performance throughout the entire life cycle of the gas-insulated equipment.

[0093] S28. Transient Overvoltage Particle Jumping Suppression Verification: Based on the smooth and gradual electric field mitigation structure of the pre-conductor trap 3, this method verifies particle jumping suppression under extreme and complex operating conditions encountered by GIS / GIL equipment, such as operational overvoltage, lightning strike overvoltage, and transient pressure fluctuations. Conventional straight, single-circular-arc trap structures are prone to local field strength surges under transient overvoltage, inducing repolarization, jumping, and suspension of deposited particles, leading to the risk of secondary firefly discharge. This invention employs a two-segment differentiated curvature passivation transition structure, without sharp electric field corners or structural abrupt changes, effectively mitigating field strength distortion and sudden electric field changes caused by transient voltage impacts, and smoothing the amplitude of instantaneous electric field fluctuations inside the cavity. Through structural electric field equalization optimization, the instantaneous electric field excitation experienced by particles under transient overvoltage conditions is strictly controlled within the critical field strength threshold for particle jumping, ensuring that the transient jumping kinetic energy of the particles is always lower than their own suspension critical kinetic energy, preventing the settled particles from jumping, suspending, and drifting backward again. This verification method enables comprehensive particle stability control under normal rated operating conditions, air pressure fluctuation conditions, and transient overvoltage extreme conditions. It solves the technical problem of particle re-jumping and escaping under impact voltage conditions in traditional traps, and ensures the continuous stability of the particle capture system under complex conditions.

[0094] Example 2.

[0095] This embodiment 2 discloses a dual-trap method to improve the particle capture rate of gas-insulated equipment, wherein in step S3, the dynamic adaptive calibration model of the gas pressure electric field is as follows.

[0096] .

[0097] .

[0098] In the formula, is the dynamic pressure correction coefficient, and is the output variable of the model calculation. Real-time for equipment Air pressure is collected in real time by the equipment's pressure sensor; This is the rated reference pressure, which is the industry standard design value. For low-voltage offset correction constant, For pressure attenuation coefficient, The baseline safety lower limit coefficient is the convergence setpoint obtained from multiple rounds of simulation scanning fitting across the entire pressure range of 0.4~0.6MPa; e is a natural constant.

[0099] The dynamic optimal electric field ratio range is: .

[0100] High pressure locks in the standard range, while low pressure adaptively expands the safety margin, solving the problem of mismatch between high and low pressure operating conditions.

[0101] Example 3.

[0102] This embodiment 3 discloses a dual-trap method for improving the particle capture rate of gas insulation equipment, wherein step S5 includes the following steps.

[0103] S51, Particle Characteristic Test under Traps-Free Baseline Operating Conditions. (Refer to...) Figure 3 and Figure 4 L3 represents the firefly particles blocked by the guide rod trap; L4 represents the particle trajectory; L5 represents the particle's trajectory into the bending trap; and L6 represents the bending trap driving the particles away from the insulator. The positioning and assembly of the bending trap need to be determined based on the simulation and experimental results of the particle trajectory. Under the baseline condition without the installation of the front guide rod trap, the particle trajectory and landing point distribution were tested across the entire area. The results showed that the concentrated landing point of the metal particles was located 89mm downstream of the bending trap, with a peak landing point probability of only 11.5%. The particle movement was highly discrete, and the landing point distribution was chaotic and irregular. The traditional empirical arrangement method of a single trap could not accurately match the particle movement area, resulting in extremely low capture efficiency of a single trap and a large number of capture blind spots.

[0104] S52. Verification of the trajectory control effect of the double-circular arc trap. After adding the optimized variable-angle guide rod trap, relying on the characteristics of double-circular arc gradual guidance, angle constraint and unidirectional transport, the particle movement law inside the GIL / GIS equipment is reconstructed, the discrete particle trajectory is greatly reduced, the effective landing point range of particles is widened to 80~280mm, the peak landing probability is shifted to 207mm, the peak percentage is increased to 19.4%, the concentration of particle movement is greatly improved and the orderliness of the trajectory is significantly enhanced, providing core data support for the precise positioning and installation of the rear trap.

[0105] S53, Bend Trap Alignment Installation. (Refer to...) Figure 3 and Figure 4 For standard GIL long pipeline equipment, the core installation position is the peak area of ​​the 207mm particle impact point. A post-bending trap is arranged, and the orientation of the trap slot is simultaneously calibrated to match and seamlessly connect the trap slot with the directional incident trajectory of the particles, realizing directional driving, trapping, and non-offset capture of particles. For segmented GIS equipment, the 207mm benchmark impact point is proportionally converted according to its own cylinder structure size to obtain the installation point adapted to the GIS equipment. This achieves precise alignment and deployment of post-traps for both types of equipment, completely eliminating the matching deviation and capture blind spot of traditional layout methods.

[0106] Example 4.

[0107] This embodiment 4 discloses a dual-trap method to improve the particle capture rate of gas-insulated equipment. In step S6, a series capture rate model is established, and a first-stage in-situ initial suppression is performed. The series capture rate model is established as follows.

[0108] .

[0109] In the formula, For the overall particle capture rate, For the in-situ capture rate of the first-stage guide rod trap, The final capture rate of the secondary bending trap is obtained from simulation statistics and experimental measurements.

[0110] Establish a rigid criterion for particle rebound velocity to prevent secondary escape.

[0111] In the formula, is the final radial rebound velocity of the particle, and is the output value calculated by the model. Here, represents the particle incident velocity, and represents the input quantity for motion simulation monitoring. The damping loss coefficient of the bending trap grid structure is determined by structural mechanics tests. This defines the effective capture criterion. If the condition is met, the device is considered permanently locked, with no secondary levitation or reverse escape.

[0112] Example 5.

[0113] This embodiment discloses a dual-trap method for improving the particle capture rate of gas-insulated equipment, wherein step S7 includes the following steps.

[0114] S71, Long-distance GIL pipeline: It adopts a periodic array layout, and the optimal spacing calculation formula is as follows.

[0115] .

[0116] In the formula, To determine the optimal spacing for the dual-trap units, The average axial transport velocity of the particles is obtained from the statistical mean value of the flow field dynamics simulation. This is the maximum capture time limit for the system, and a fixed threshold for test calibration; The inherent natural escape rate of particles under standard operating conditions is a fixed value obtained by fitting a blank control test of a long pipeline. The optimal layout spacing is 8~12m / group to achieve blind-spot-free coverage of long pipelines.

[0117] The dual-trap unit is a standardized and fully functional minimum unit for particle collaborative capture, consisting of a guide rod trap 3 and a bending trap 4. The guide rod trap 3 is responsible for particle trajectory control, stratified energy dissipation, and near-zero electric field suppression of firefly re-jumping. The bending trap 4 is responsible for precise final capture of particles, grid damping locking, and prevention of secondary escape. The two traps, guide rod trap 3 and bending trap 4, are functionally coupled and work together to complete the complete capture process of directional migration, energy dissipation and settling of particles, and permanent locking.

[0118] The S72 and GIS equipment consists of segmented, independent short air chambers, eliminating long-distance axial particle transport. They do not employ array deployment; each busbar air chamber is independently configured with a set of dual trap units to achieve full coverage capture, with no coupling interference and no blind spots.

[0119] Example 6.

[0120] This embodiment discloses a dual-trap method for improving the particle capture rate of gas-insulated equipment, wherein in step S8, referring to Figure 5 L1 represents the particle landing position curve without the guide rod trap; L2 represents the particle landing position curve with the guide rod trap. Effective capture determination and performance testing use a radial rebound velocity of less than 0.3 m / s after the particle enters the trap as the criterion for effective capture, combined with... Figure 5 The particle trajectory and collision effect are shown. The guide rod trap, as an equipotential structure, has no potential difference with the high-voltage conductor, and its internal electric field strength is extremely low. When metal particles move to the vicinity of the guide rod trap under the influence of the electric field force, the electric field force decreases significantly after entering the low electric field region, and the kinetic energy dissipates rapidly, making it impossible to maintain firefly-like motion. Simultaneously, the variable tilt angle structure of the guide rod trap causes the particles to bounce at a large angle away from the insulator after collision, blocking the reciprocating bouncing path near the insulator. Without the guide rod trap, the particle rebound angle is small, making it easy to escape towards the insulator. After adding the guide rod trap, the particle rebound angle increases significantly, and it is directed towards the bending trap direction, achieving a synergistic effect of directional driving, precise introduction, and stable capture. Test results show that the average capture time of metal particles is less than 30 seconds, and the capture rate increases from 63.1% to 68.4%, effectively reducing the risk of surface flashover of the insulator. Long-term continuous operation shows no repeated particle bouncing, no partial discharge, no electric field distortion, and no insulation degradation problems, significantly improving the equipment's operational stability and insulation safety.

[0121] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A dual-trap method for improving the particle capture rate of gas-insulated equipment, characterized in that, Includes the following steps: Obtain the total axial length of the trap; A double-circular-arc geometric closed-loop model is constructed. The input of the double-circular-arc geometric closed-loop model is the total axial length of the trap. The instantaneous radius of curvature of the first segment of the gradual circular arc and the fixed radius of curvature of the second segment of the converging circular arc are obtained. Based on the instantaneous radius of curvature of the first segment of the gradual arc and the fixed radius of curvature of the second segment of the closing arc, a first trap is constructed; The instantaneous radius of curvature of the first segment of the gradient arc is different from the fixed radius of curvature of the second segment of the closing arc; The first trap is mounted on the outside of the high-voltage conductor of the gas-insulated equipment, and the second trap is placed on the metal-sealed outer cylinder of the gas-insulated equipment; the root electric field is slowed down by the first trap, and the trajectory of the charged particle is guided by the first trap to obtain the guided particle. The second trap intercepts the guided particles.

2. The dual-trap method for improving the particle capture rate of gas-insulated equipment according to claim 1, characterized in that... The first arc segment is formed based on the instantaneous radius of curvature of the first gradually changing arc; the second arc segment is formed based on the fixed radius of curvature of the second converging arc. The angle between the tangent of the second arc segment and the horizontal direction is 13.5° to 15.0°.

3. The dual-trap method for improving the particle capture rate of gas-insulated equipment according to claim 2, characterized in that... The first trap is coated with epoxy resin, and the second trap is coated with polyimide. The residual charge coefficient of the epoxy resin coating is less than or equal to 0.22, the residual charge coefficient of the polyimide coating is greater than or equal to 0.35, and the difference between the residual charge coefficient of the polyimide coating and the residual charge coefficient of the epoxy resin coating is greater than or equal to 0.

13.

4. The dual-trap method for improving the particle capture rate of gas-insulated equipment according to claim 1, characterized in that... The first trap adopts a composite cavity structure with continuously varying depths. The composite cavity structure is a radially concave cavity that smoothly varies from shallow to deep along the incident direction of the particles. The radial concavity depth of the radially concave cavity varies from 10.0 mm to 30.0 mm.

5. The dual-trap method for improving the particle capture rate of gas-insulated equipment according to claim 1, characterized in that... The double-circular-arc geometric closed-loop model is as follows: ； In the formula, x is the axial coordinate of the trap, and L is the total axial length of the trap; This represents the instantaneous radius of curvature of the first segment of the gradually changing circular arc; The radius of curvature of the second segment's closing arc is a fixed value. It is the local maximum electric field intensity on the surface of the trap. This is a preset dielectric insulation safety threshold.

6. The dual-trap method for improving the particle capture rate of gas-insulated equipment according to claim 1, characterized in that... It also includes a dynamic adaptive calibration step for the pneumatic electric field, constructing a dynamic adaptive calibration model for the pneumatic electric field, based on real-time equipment operation. The pressure is subject to adaptive correction, and the dynamic adaptive calibration model for the pressure electric field is as follows: ； In the formula, This is the dynamic pressure correction factor. Real-time equipment air pressure; The rated reference pressure, For low-voltage offset correction constant, For pressure attenuation coefficient, is the baseline safety lower limit coefficient; e is a natural constant.

7. The dual-trap method for improving the particle capture rate of gas-insulated equipment according to claim 1, characterized in that... It also includes a dual-trap hierarchical collaborative closed-loop escape prevention control step, specifically including: constructing a dual-level series closed-loop escape prevention and capture system consisting of a first-level in-situ initial suppression and a second-level final capture and locking mechanism; completing the initial kinetic energy dissipation and preliminary capture of particles through the first trap, and then using the second trap to perform secondary damping and locking capture of particles with residual kinetic energy; and constraining the final radial rebound velocity of particles after the first-level in-situ initial suppression and the second-level final capture and locking mechanism to below 0.3 m / s.

8. The dual-trap method for improving the particle capture rate of gas-insulated equipment according to claim 1, characterized in that... The actual cumulative operating time of the gas-insulated equipment is collected in real time, and the aging performance of the first trap is compensated based on the actual cumulative operating time. The aging performance of the second trap is compensated based on the actual cumulative runtime.

9. A dual-trap device for improving the particle capture rate of gas-insulated equipment using the dual-trap method for improving particle capture rate according to any one of claims 1-8, comprising a basin-type insulator, a high-voltage conductor, a first trap, a second trap, and a metal-sealed outer cylinder, characterized in that... : A basin-type insulator is fixedly assembled inside the metal-sealed outer cylinder, and a high-voltage conductor is fixedly inserted through the center of the basin-type insulator. A first trap is fixedly installed inside the metal-sealed outer cylinder and outside the high-voltage conductor. The first trap is provided with a guide rod trap opening structure; the first trap as a whole adopts a non-uniform curvature double circular arc gradient curved surface shape; A second trap is fixedly provided on the inner side of the cylinder wall of the metal-sealed outer cylinder. The second trap is a single-slot grid buffer structure composed of multiple sets of bent baffles evenly arranged.

10. The dual-trap device for improving the particle capture rate of gas insulation equipment according to claim 9, characterized in that... The first trap adopts an integrated conductive metal structure and is sleeved and installed on the high voltage conductor on the convex side of the basin insulator.

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