Lightning protection effect evaluation method and device based on inner gap design

Abstract

The invention provides a lightning protection effect evaluation method and device based on inner gap design, and the method comprises the steps: calculating the plasma density distribution, analyzing the bifurcation energy distribution, recognizing the coordinates of an electric field concentration region according to spatial distribution parameters, and obtaining a plasma density distribution map if a deviation angle or the number of bifurcations exceeds a threshold value; performing density gradient change trend analysis on the plasma density distribution map, determining the current position coordinates of an arc root attachment point, and obtaining an attachment point migration path by combining time sequence coordinate change track analysis; and recalculating the adjusted plasma density distribution uniformity index through a multi-path adaptive geometric structure, and performing compensation adjustment on an arc temperature gradient non-uniform region to obtain a stable plasma density distribution state.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of information technology, and in particular to a lightning protection effect evaluation method and device based on inner gap design. BACKGROUND

[0002] Lightning protection is the core guarantee for the safe operation of power systems, communication facilities, aerospace and other fields, and its importance lies in effectively reducing the risk of equipment damage and personnel casualties caused by lightning strikes. However, the arc extinguishing performance research of existing lightning protection equipment mainly focuses on the arc behavior under single working condition, ignoring the dynamic influence of the spatial distribution characteristics of arc channel in complex geometric structure on arc extinguishing efficiency. This leads to the difficulty of lightning protection equipment in stable control of electric field distribution in actual lightning scene, and further affects the arc extinguishing performance and equipment reliability. The design defects of current lightning protection equipment mainly reflect the insufficient adaptability to inner gap geometry. Traditional methods are usually based on fixed geometric parameters, and the dynamic changes of electric field concentration phenomenon under lightning impact are not fully considered. This static design cannot cope with the offset or branching behavior of arc channel in different geometric shape gaps, leading to uneven plasma density distribution and increased uncertainty of arc root attachment point migration. For example, in some arc-shaped or conical gap structures, electric field concentration may cause local overheating, accelerate material aging, and even lead to arc extinguishing failure. The core challenge lies in the dynamic coupling of spatial distribution characteristics of arc channel and inner gap geometric parameters. The offset or branching of arc channel will directly change the plasma density distribution, and further affect the migration trajectory of arc root attachment point. This trajectory change not only aggravates the unevenness of electric field, but also may lead to uncontrolled energy dissipation in the arc extinguishing process. For example, under lightning impact, the arc root may migrate rapidly on the inner wall of the gap, causing local electric field to be too strong, causing secondary breakdown, and reducing the service life of the equipment. Optimization of inner gap geometric parameters needs to be dynamically adjusted to adapt to these changes, but how to realize real-time adaptation of parameters in complex electric field environment has become a technical problem to be solved. Therefore, how to optimize the inner gap geometric parameters to dynamically regulate the spatial distribution characteristics of the arc channel, stabilize the plasma density distribution and control the migration trajectory of the arc root attachment point, has become a key problem to improve the arc extinguishing performance and overall reliability of lightning protection equipment. SUMMARY

[0003] The present application provides a lightning protection effect evaluation method based on inner gap design, mainly including:

[0004] The space coordinate data of the arc channel in the inner gap of the lightning protection equipment is acquired, the arc deflection angle and the bifurcation position are calculated through the coordinate difference value, the arc channel length and the bifurcation branch number are calculated, and the space distribution state parameters of the arc channel are obtained; the plasma density distribution is calculated according to the space distribution state parameters, the bifurcation energy distribution is analyzed, the electric field concentration region coordinates are identified, and the plasma density distribution map is obtained; the density gradient change trend of the plasma density distribution map is analyzed, the current position coordinates of the arc root adhesion point are determined, the adhesion point migration path is obtained by combining the time sequence coordinate change trajectory analysis, the electric field intensity and the gradient distribution of different positions in the inner gap are analyzed according to the adhesion point migration path modeling, the electric field distribution characteristic parameters are obtained, the electric field concentration region is marked as a high-risk region, and the electric field distribution risk assessment result is obtained; the distribution range and the risk level of the high-risk region are determined according to the electric field distribution risk assessment result, the gap angle deviation and the electrode surface roughness are adjusted, and the optimized geometric parameter configuration scheme is obtained; the inner gap structure is adjusted according to the optimized geometric parameter configuration scheme, the bifurcation branch number is recalculated, the gap width and the electrode material conductivity parameters corresponding to each bifurcation path are synchronously adjusted, and the multi-path adaptive geometric structure is obtained; the plasma density distribution uniformity index is recalculated through the multi-path adaptive geometric structure, the arc temperature gradient non-uniform region is adjusted, and the stable plasma density distribution state is obtained; the density uniform region boundary and the density gradient change law are determined based on the stable plasma density distribution state, the migration trajectory of the arc root adhesion point is limited, the adhesion point temperature and pressure change attribute are adjusted, and the controllable arc root adhesion behavior is obtained.

[0005] Further, the space coordinate data of the arc channel in the inner gap of the lightning protection equipment is acquired, the arc deflection angle and the bifurcation position are calculated through the coordinate difference value, the arc channel length and the bifurcation branch number are calculated, and the space distribution state parameters of the arc channel are obtained, including:

[0006] The three-dimensional space coordinate data of each sampling point on the arc channel in the inner gap of the lightning protection equipment is acquired, the two-dimensional projection coordinates of the arc channel are extracted, the three-dimensional space coordinates are reconstructed, the coordinate difference value between adjacent sampling points is calculated, and the direction vector of each arc channel segment is obtained; the included angle between adjacent channel segments is calculated according to the direction vector of each arc channel segment, the bifurcation point position is determined, the three-dimensional coordinates of the bifurcation point are recorded, the branch number is counted, and the deflection angle of each branch relative to the main channel is calculated; the Euclidean distance between adjacent sampling points is accumulated based on the three-dimensional space coordinates, the arc main channel length and the branch channel length are obtained, the bifurcation point coordinates, the branch number, the deflection angle and the channel length are comprehensively considered, and the space distribution state parameters of the arc channel are determined.

[0007] Further, the plasma density distribution is calculated according to the spatial distribution state parameter, the branch energy distribution is analyzed, the coordinates of the electric field concentration region are identified, and the plasma density distribution map is obtained, comprising:

[0008] According to the three-dimensional coordinates of the branch point in the spatial distribution state parameter and the channel length, the cross-sectional area and volume of each channel segment are calculated, the initial current density value is obtained by dividing the arc current value by the channel volume, and the plasma density value of each channel segment is determined according to the corresponding relationship between current density and plasma density; according to the plasma density value and the current density value, the current value of each branch channel is distributed, the energy value of each branch unit length is calculated, and the branch energy distribution value is obtained; the energy density is calculated by the branch energy distribution value, the space region with energy density exceeding the threshold value is identified as the electric field concentration region, the center point coordinates of the electric field concentration region are recorded, the continuous density field data is generated by using the three-dimensional linear interpolation method, and the plasma density distribution map is constructed.

[0009] Further, the density gradient change trend of the plasma density distribution map is analyzed to determine the current position coordinates of the arc root attachment point, and the migration path of the attachment point is obtained by combining the time sequence coordinate change trajectory, comprising:

[0010] The density gradient of each space point in the plasma density distribution map is calculated, the adjacent points in six orthogonal directions of each point are selected, the density difference is divided by the distance between the points to obtain the gradient component in each direction, the three-dimensional gradient vector is synthesized, and the continuous region with gradient value exceeding the threshold value is identified as the arc root candidate region; the density value change is tracked along the gradient direction to determine the point with local maximum density and gradient component tending to zero as the arc root attachment point, and the three-dimensional coordinates of the arc root attachment point are recorded; the plasma density distribution map at different time is repeatedly processed to obtain the attachment point coordinates at each time, form a time sequence coordinate data set, connect the coordinates at each time to generate a continuous trajectory curve, and obtain the migration path of the attachment point.

[0011] Further, the electric field strength and gradient distribution at different positions in the inner gap are analyzed according to the attachment point migration path modeling, the electric field distribution characteristic parameters are obtained, the electric field concentration region is marked as a high-risk region, and the electric field distribution risk assessment result is obtained, comprising:

[0012] According to the coordinate sequence on the attachment point migration path, combined with the gap geometric size and electrode position data, the grid is divided, the potential value of each grid node is calculated, and the electric field strength value and gradient data are obtained; the maximum value, average value and standard deviation of the electric field strength value are extracted, the distribution uniformity is calculated, and the region with electric field strength exceeding the threshold value is identified as the electric field concentration region; it is judged whether the position on the attachment point migration path enters the electric field concentration region or not, the high-risk region is marked, the high-risk region coordinates, volume and electric field strength peak value are recorded, and the electric field distribution risk assessment result is generated.

[0013] Further, the distribution range and risk level of the high-risk area are determined according to the electric field distribution risk assessment result, the gap angle deviation and the electrode surface roughness are adjusted, and an optimized geometric parameter configuration scheme is obtained, which comprises:

[0014] According to the high-risk area coordinates and the electric field intensity peak value in the electric field distribution risk assessment result, the risk level is divided, the spatial distribution range boundary of each level is determined, the arc deflection angle and the bifurcation energy distribution value in the high-risk area are obtained, the energy density is calculated, and the gap angle correction value is determined; the relative inclination angle between the electrodes is adjusted according to the arc deflection angle and the energy density, and the electrode surface roughness value is adjusted to the target value; the optimized geometric parameter configuration scheme is generated in combination with the corrected electrode spacing, inclination angle and roughness parameters.

[0015] Further, the distribution range and risk level of the high-risk area are determined according to the electric field distribution risk assessment result, the gap angle deviation and the electrode surface roughness are adjusted, and an optimized geometric parameter configuration scheme is obtained, which comprises:

[0016] According to the electrode spacing, inclination angle and roughness parameters in the optimized geometric parameter configuration scheme, the relative position of the electrodes is adjusted, the adjusted arc development data is collected, and the bifurcation point position and the number of branches are re-identified; if the number of bifurcation branches exceeds the threshold value, the electric field intensity distribution around each bifurcation path is calculated, the gap width is adjusted according to the electric field intensity value, and the differential conductivity electrode material is configured, so that the current density of each bifurcation path is balanced, and a multi-path adaptive geometric structure is generated.

[0017] Further, the distribution range and risk level of the high-risk area are determined according to the electric field distribution risk assessment result, the gap angle deviation and the electrode surface roughness are adjusted, and an optimized geometric parameter configuration scheme is obtained, which comprises:

[0018] Through the gap width and material conductivity data of the multi-path adaptive geometric structure, the plasma density value of each spatial position is recalculated, the density uniformity index is calculated, and the positions where the density value deviates from the average value by more than the threshold value are recorded; the temperature value and temperature gradient are calculated according to the plasma density value, and the area where the temperature gradient exceeds the threshold value is identified; the electric field intensity value is iteratively adjusted for the temperature gradient, and the local electrode spacing is adjusted, so that the stable plasma density distribution state is obtained when the density difference value is less than the threshold value.

[0019] Further, the distribution range and risk level of the high-risk area are determined according to the electric field distribution risk assessment result, the gap angle deviation and the electrode surface roughness are adjusted, and an optimized geometric parameter configuration scheme is obtained, which comprises:

[0020] Based on the stable plasma density distribution state, the region with density change less than the threshold is identified, the boundary coordinates are determined, and the density gradient change rule is calculated; the attachment point migration constraint range is set according to the boundary of the density uniform region, the electrode spacing outside the boundary is increased, and the electric field strength is reduced to obtain the controllable arc root attachment behavior.

[0021] A lightning protection effect evaluation device based on an inner gap design, the system comprises:

[0022] An arc space coordinate acquisition module is configured to obtain arc channel space coordinate data in the inner gap of the lightning protection device, calculate the arc deflection angle and bifurcation position through coordinate difference, calculate the arc channel length and bifurcation branch number, and obtain the spatial distribution state parameters of the arc channel;

[0023] An arc morphology analysis module is configured to calculate the plasma density distribution according to the spatial distribution state parameters, analyze the bifurcation energy distribution, identify the coordinates of the electric field concentration region, and obtain the plasma density distribution map;

[0024] A plasma density calculation module is configured to analyze the density gradient change trend of the plasma density distribution map, determine the current position coordinates of the arc root attachment point, and obtain the attachment point migration path by combining the time sequence coordinate change trajectory analysis;

[0025] An attachment point trajectory analysis module is configured to model and analyze the electric field strength and gradient distribution at different positions in the inner gap according to the attachment point migration path, obtain the electric field distribution characteristic parameters, mark the electric field concentration region as a high-risk region, and obtain the electric field distribution risk evaluation result;

[0026] An electric field risk evaluation module is configured to determine the distribution range and risk level of the high-risk region according to the electric field distribution risk evaluation result, adjust the gap angle deviation and electrode surface roughness, and obtain an optimized geometric parameter configuration scheme;

[0027] A geometric structure optimization module is configured to adjust the inner gap structure according to the optimized geometric parameter configuration scheme, recalculate the bifurcation branch number, and synchronously adjust the gap width and electrode material conductivity parameters corresponding to each bifurcation path to obtain a multi-path adaptive geometric structure;

[0028] A multi-path adjustment module is configured to recalculate the plasma density distribution uniformity index through the multi-path adaptive geometric structure, adjust the arc temperature gradient non-uniform region, and obtain a stable plasma density distribution state;

[0029] An arc stability control module is configured to determine a density uniform region boundary and a density gradient variation law based on the stable plasma density distribution state, limit a migration trajectory of an arc root attachment point, adjust an attachment point temperature and a pressure variation attribute, and obtain a controllable arc root attachment behavior.

[0030] The technical scheme provided by the embodiment of the present application can have the following beneficial effects:

[0031] The application discloses a lightning protection effect evaluation method and device based on an inner gap design, and solves the problems of electric field concentration and uneven plasma density caused by arc deviation, bifurcation and attachment point migration. By obtaining arc channel spatial coordinate data, calculating the deviation angle, bifurcation position and channel length, analyzing the plasma density distribution and electric field concentration area, and determining the arc root attachment point migration path, the high-risk electric field concentration area is evaluated, the gap geometric structure and electrode material conductivity are optimized, the bifurcation path gap width is adjusted, the density optimization algorithm is combined to compensate for the uneven temperature gradient, and finally the controllability of the plasma density uniform distribution and the attachment point migration is realized. The application significantly improves the arc stability, reduces the electric field concentration degree of the high-risk area, optimizes the performance of the lightning protection equipment, and ensures the efficient and stable arc extinguishing effect. BRIEF DESCRIPTION OF DRAWINGS

[0032] Fig. 1 A flowchart of a lightning protection effect evaluation method based on an inner gap design of the application.

[0033] Fig. 2 A structural schematic diagram of a lightning protection effect evaluation device based on an inner gap design of the application. DETAILED DESCRIPTION

[0034] The technical scheme of the present application will be described clearly and completely below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0035] As Figs. 1-2 , the lightning protection effect evaluation method and device based on the inner gap design can specifically include:

[0036] In step S101, the arc channel spatial coordinate data in the inner gap of the lightning protection equipment is obtained, the arc deviation angle and the bifurcation position are calculated through the coordinate difference value, the arc channel length and the bifurcation branch number are calculated, and the spatial distribution state parameters of the arc channel are obtained.

[0037] Three-dimensional spatial coordinate data of each sampling point on the arc channel in the gap of the lightning protection device is acquired, an optical imaging device is used to record the development process of the arc, two-dimensional projection coordinates of the arc channel in each frame of image are extracted, three-dimensional spatial coordinates are reconstructed according to the internal and external parameter matrices of the two cameras and the pixel coordinates of the corresponding points through a parallax calculation method in the binocular vision principle, the coordinate difference value between adjacent sampling points is calculated, and the directional vector of each arc channel segment is obtained. The included angle between adjacent channel segments is calculated by using the directional vector of each arc channel segment, the cosine value of the included angle of the two directional vectors is obtained through the vector inner product formula, and then the included angle value is obtained through the inverse cosine function. If the included angle exceeds a preset bifurcation judgment threshold, the position is determined as a bifurcation point, the three-dimensional coordinate position of the bifurcation point is recorded, the number of branches branched from the main channel is counted, and the offset angle of each branch relative to the main channel is calculated through the included angle between the branch directional vector and the main channel directional vector. Based on the three-dimensional spatial coordinates of the sampling points, the arc main channel length is obtained by accumulating the Euclidean distances between adjacent sampling points, the Euclidean distance is obtained by squaring and square rooting the coordinate difference between two adjacent points, the branch length of each branch channel starting from the bifurcation point is calculated by using the same method, and the spatial distribution state parameters of the arc in the gap of the lightning protection device are determined by comprehensively considering the bifurcation point coordinates, the branch number, the offset angle and the channel length data.

[0038] For example, in the actual application of the lightning protection device, the spatial distribution state of the arc channel directly affects the protection effect of the device. When the optical imaging device records the development process of the arc, a high-speed camera is usually used with a synchronous trigger system to ensure that the complete process of arc formation and development is captured.

[0039] Specifically, when the lightning current passes through the gap of the lightning protection device, the arc is formed and developed in a very short time, the high-speed camera takes pictures at a speed of tens of thousands of frames per second, and each frame of image contains two-dimensional projection information of the arc channel at that moment. The application of the binocular vision principle makes three-dimensional reconstruction possible.

[0040] In a possible implementation, two cameras simultaneously take pictures of the arc channel from different angles, the internal parameter matrix of the camera is obtained through calibration, including focal length, principal point coordinates and the like, and the external parameter matrix, including a rotation matrix and a translation vector. When the same arc sampling point is identified in two images, according to the triangulation principle, the actual position of the point in the three-dimensional space is calculated in combination with the camera parameters and the pixel coordinates of the corresponding points. The advantage of this method is that the spatial form of the arc channel can be accurately restored, providing reliable basic data for subsequent analysis.

[0041] It should be noted that the calculation of the direction vector is crucial for identifying the arc bifurcation. The difference in coordinates between adjacent sampling points forms a vector reflecting the development direction of the arc in that section. When the arc encounters a region of uneven electric field or changes in medium characteristics during propagation, bifurcation may occur. By calculating the included angle of the direction vectors of adjacent sections, the bifurcation position can be accurately determined.

[0042] Illustratively, when the included angle exceeds 30 degrees, it is generally considered that a significant bifurcation has occurred. This threshold is based on extensive experimental observations and analysis of arc physical characteristics.

[0043] In one embodiment, the accumulation of Euclidean distance is actually the length calculation after the discretization of the arc channel. Since the arc channel often presents a curved shape, it is difficult to directly measure its length. By decomposing the channel into multiple small sections, the length of each section is represented by the Euclidean distance between adjacent sampling points, and the total length is obtained after accumulation. This method is not only suitable for the main channel, but also effective for the branch channel. The offset angle of the branch reflects the irregularity of the arc development, and these parameters together constitute a complete description of the spatial distribution state of the arc.

[0044] If the offset angle or the number of bifurcations exceeds the threshold, the plasma density distribution is calculated based on the spatial distribution parameters, the bifurcation energy distribution is analyzed, the coordinates of the electric field concentration region are identified, and the plasma density distribution map is obtained.

[0045] If the offset angle or the number of bifurcations of the arc channel exceeds the preset threshold, the three-dimensional coordinates of the bifurcation points, the length data of each branch channel, and the channel diameter data in the spatial distribution parameters are obtained, the cross-sectional area of each channel section is calculated based on the circular cross-section formula, the volume of each channel section is calculated by multiplying the cross-sectional area by the channel length, the initial current density value is obtained by dividing the arc current value obtained from the current monitoring device by the channel volume, and the plasma density value of each channel section is determined based on the corresponding relationship between current density and plasma density in the Saha ionization equation. Based on the plasma density value and the current density value of each channel section, the energy distribution ratio of each bifurcation channel is calculated, the current value is distributed according to the product of the conductivity and the cross-sectional area of each branch channel based on the Kirchhoff's current law that the main channel current at the bifurcation point is equal to the sum of the branch currents, and the energy value per unit length of each branch is calculated by Joule's law to obtain the distribution value of the bifurcation energy in each channel section. Using the bifurcation energy distribution value of each channel section, the energy density is calculated by dividing the energy value by the channel volume, the spatial region with energy density exceeding the preset threshold is identified as the electric field concentration region, the three-dimensional coordinates of the center point of the region are recorded, and the continuous density field data between the sampling points is generated using the three-dimensional linear interpolation method based on the plasma density value of each sampling point to construct the plasma density distribution map.

[0046] For example, in the arc monitoring of lightning protection equipment, when the arc channel appears significant deviation or bifurcation, it indicates that the electric field distribution is abnormal, and at this time the spatial distribution characteristics of the plasma need to be analyzed in depth.

[0047] Specifically, the acquisition of channel diameter data is usually based on optical measurement results, which is determined by analyzing the boundary of the arc light-emitting area. The arc channel presents a cylindrical shape at high temperature, and its cross section can be approximated as a circle with a diameter generally in the order of millimeters. The cross-sectional area can be obtained according to the formula for the area of a circle.

[0048] It should be noted that the Saha ionization equation describes the relationship between ionization degree, temperature and pressure in plasma. In the arc channel, high temperature causes gas molecules to ionize to form plasma. The greater the current density, the more electric charges pass through per unit volume, and the higher the plasma density. This correspondence allows the distribution state of the plasma to be calculated by measuring the current and geometric parameters. The current monitoring device usually uses a Rogowski coil or a shunt, which can record the arc current value through the lightning protection equipment in real time.

[0049] In one possible implementation, the application of Kirchhoff's current law at the arc bifurcation point embodies the principle of charge conservation. The current of the main channel must be completely distributed to each branch at the bifurcation point, and there is no accumulation or disappearance of electric charges. The current distribution ratio of each branch depends on its conductance characteristic. The branch with high conductivity and large cross-sectional area will carry more current. This distribution mechanism is similar to the distribution of water flow in a bifurcated pipe, and the channel with less resistance has more flow. The application of Joule's law here reveals the energy conversion process. When the current passes through the plasma channel with a certain resistance, the electrical energy is converted into heat energy, and the energy per unit length reflects the energy density of the channel. The area with high energy density usually corresponds to the position with high electric field strength. These areas have higher plasma temperature and more complete ionization, and have more significant impact on lightning protection equipment.

[0050] Preferably, the application of three-dimensional linear interpolation method enables the discrete sampling point data to form a continuous density field. This method calculates the density value of any spatial position based on the known plasma density value of the sampling point through linear weight. The interpolation process takes into account the relative relationship of the spatial position. The closer the position is to the sampling point, the greater the influence of the density value of the sampling point. The generated plasma density distribution map presents the variation of density in space in three-dimensional form. Different density values can be represented by different colors or isosurfaces, which intuitively reflects the distribution characteristics of the plasma in the arc channel, and provides an important basis for evaluating the working state of lightning protection equipment and optimizing the design.

[0051] Step S103, the density gradient change trend of the plasma density distribution map is analyzed, the current position coordinates of the arc root attachment point are determined, and the migration path of the attachment point is obtained by combining the time sequence coordinate change trajectory analysis.

[0052] The density gradient of each spatial point in the plasma density distribution map is calculated, the adjacent points in the six orthogonal directions of each point are selected, the density difference between the point and the adjacent point is calculated, and the gradient component in each direction is obtained by dividing the distance between the points, the three-dimensional gradient vector is synthesized, the gradient size and direction of each point are recorded, and the continuous region with gradient value exceeding the preset threshold is identified as the arc root candidate region. In the arc root candidate region, the change of the density value is tracked along the gradient direction, the point with the local maximum density and the gradient component in each direction tending to zero is found, the point is determined as the arc root attachment point at the current time, the three-dimensional coordinate position is recorded, the above processing process is repeated for the plasma density distribution maps collected at different times, the attachment point coordinates corresponding to each time are obtained, and a time sequence coordinate dataset is formed. The displacement vector is calculated by using the attachment point coordinates of adjacent time in the time sequence coordinate dataset, and the direction and size are recorded, the attachment point positions at each discrete time are connected by a spline interpolation method, a continuous spatial trajectory curve is generated, and the migration path of the attachment point on the surface of the lightning protection equipment is obtained according to the tangent direction change and curvature characteristics of each point on the trajectory curve.

[0053] For example, in the arc monitoring process of the lightning protection equipment, the calculation of the density gradient is a key link to understand the behavior of the arc.

[0054] Specifically, the distribution of plasma density in space is not uniform, and the density gradient reflects the degree and direction of this non-uniformity. Six orthogonal directions are selected for gradient calculation, because in the three-dimensional Cartesian coordinate system, each point has six nearest neighbors in front, back, left, right, up and down. This method can fully capture the spatial variation characteristics of the density.

[0055] It should be noted that the physical meaning of the gradient vector is to indicate the direction of the fastest density growth. In the arc root region, the plasma density usually presents a gradually decreasing trend from the center to the outside, so the gradient vector points to the direction of density increase, that is, to the arc center. When the gradient value exceeds the preset threshold, it indicates that there is a sharp density change in this region. Such changes often occur near the root of the arc and the electrode because the current density is the largest and the plasma is the most concentrated.

[0056] In one possible implementation, the process of finding the attachment point is similar to the principle of the mountain climbing algorithm. Starting from an arbitrary point within the candidate region, move along the gradient direction, the density value will gradually increase until reaching the local maximum point. At this point, the gradient components in various directions tend to zero, meaning that no matter which direction to move, the density will decrease. This local maximum point is the attachment point of the arc root, which represents the actual contact position of the arc with the surface of the lightning protection device. The acquisition of time series data involves a continuous monitoring process. During the lightning strike process, although the duration of the arc is short, the high-speed imaging device can continuously shoot at the millisecond or even microsecond level. After processing each image, the corresponding plasma density distribution map can be generated, and by applying the same gradient analysis method to each map, the attachment point position at that time can be obtained. This continuous monitoring reveals the dynamic change process of the attachment point over time.

[0057] Preferably, the application of the spline interpolation method in constructing the migration path ensures the smoothness of the trajectory. Discrete attachment point coordinates can only provide position information at limited time points, while the actual migration process is continuous. Spline interpolation generates a smooth curve between discrete points through mathematical methods, so that the position of the attachment point at any time can be calculated. The tangent direction of the trajectory reflects the instantaneous motion direction of the attachment point, and the curvature represents the rate of change of the motion direction.

[0058] In step S104, the electric field distribution characteristic parameters are obtained by modeling and analyzing the electric field intensity and gradient distribution at different positions of the internal gap according to the migration path of the attachment point. If the attachment point migrates to an electric field concentration region, it is marked as a high-risk region, and the electric field distribution risk assessment result is obtained.

[0059] According to the coordinate sequence on the migration path of the attachment point, combined with the pre-stored geometric size of the internal gap of the lightning protection device and the electrode position data, the finite element method is used to divide the gap space into grids, the potential values of each grid node are calculated according to the boundary conditions and Laplace equation, and the electric field intensity values at each position are obtained by dividing the potential difference between adjacent nodes by the node spacing. The rate of change of the electric field intensity in each direction in space is calculated as the electric field gradient. Using the electric field intensity values and electric field gradient data at each position, the maximum, average and standard deviation of the electric field intensity are extracted, the uniformity of the electric field distribution is calculated by the ratio of the standard deviation to the average, and the maximum value of the electric field intensity, the maximum value of the electric field gradient and the uniformity of the distribution are taken as the electric field distribution characteristic parameters. The continuous spatial region with electric field intensity exceeding the preset threshold is identified as the electric field concentration region. According to the spatial coordinate range of the electric field concentration region, it is judged whether the position of the attachment point at each time falls within the range, if the current position of the attachment point or the next position in the migration direction enters the electric field concentration region, the region is marked as a high-risk region, the position coordinates, volume size and electric field intensity peak value of the high-risk region are recorded, and the electric field distribution risk assessment result containing the region position and risk label is generated.

[0060] For example, in the electric field analysis of the lightning protection device, the finite element method is a numerical calculation method that discretizes continuous space.

[0061] Specifically, the geometric shape of the internal gap of the lightning protection device is often irregular, and the electrode can be in the form of a rod, a plate or other complex shapes. Finite element meshing is to divide this irregular space into many small tetrahedral or hexahedral elements, and the vertex of each element is called a node. The denser the mesh, the higher the calculation accuracy, but the calculation amount also increases accordingly.

[0062] It should be noted that the Laplace equation describes the distribution of electric potential in the electrostatic field. In the region without space charge, the electric potential satisfies the Laplace equation. The setting of boundary conditions is crucial, the electric potential on the surface of the electrode is usually set as a known value, and the surface of the insulating material satisfies the condition that the normal component of the electric field is zero. By solving this equation, the potential value of each node in the entire gap space can be obtained. The calculation of electric field intensity is based on the rate of change of electric potential in space. In the discrete mesh, the potential difference between adjacent nodes is divided by the node spacing to obtain the electric field component in that direction. In three-dimensional space, three components need to be calculated, and after synthesis, the size and direction of the electric field intensity are obtained. The electric field gradient further reflects the speed of change of the electric field intensity, and near the tip of the electrode, the electric field gradient is usually large.

[0063] In one possible implementation, the calculation of the uniformity of the electric field distribution adopts a statistical method. The standard deviation reflects the degree of dispersion of data, and the greater the standard deviation of the electric field intensity, the more uneven the electric field distribution. The coefficient of variation is obtained by dividing the standard deviation by the average value, and this dimensionless parameter can objectively evaluate the uniformity of the electric field distribution. When the coefficient of variation exceeds a certain threshold, it indicates that there is a significant electric field concentration phenomenon. The identification of the electric field concentration region is of great significance for risk assessment. These regions usually appear at the electrode tip, the narrowest gap or the location of structural mutations. When the attachment point of the arc root migrates to these regions, the local high electric field intensity will exacerbate the ionization process, causing the arc to become more intense and causing greater damage to the equipment.

[0064] Preferably, the risk assessment not only considers the static positional relationship, but also considers the dynamic migration process. When the attachment point moves along the migration path, the next moment position can be predicted according to the current position and the motion direction. If the predicted position enters the electric field concentration region, the region is marked as high risk in advance. This prediction mechanism makes the risk assessment have a certain early warning function, which gives time for taking protective measures.

[0065] In step S105, the distribution range and risk level of the high-risk region are determined according to the risk assessment result of the electric field distribution, the gap angle deviation is adjusted in combination with the arc deflection angle and the bifurcation energy distribution in the high-risk arc-extinguishing region, the inner gap geometric structure configuration is optimized in combination with the electrode surface roughness, and an optimized geometric parameter configuration scheme is obtained.

[0066] According to the position coordinates and the electric field intensity peak value data of the high-risk region in the electric field distribution risk assessment result, the region with an electric field intensity peak value less than a first threshold value is classified as a low-risk level, the region with a peak value between the first threshold value and a second threshold value is classified as a medium-risk level, and the region with a peak value exceeding the second threshold value is classified as a high-risk level. The spatial distribution range boundary corresponding to each level is determined, the arc deflection angle value and the bifurcation energy distribution value recorded in the high-risk arc-extinguishing region are obtained, the energy density is obtained by dividing the energy distribution value by the region volume, and the product of the deflection angle and the energy density is calculated as a gap adjustment parameter. Based on the gap adjustment parameter, the correction amount of the gap angle is determined, and when the adjustment parameter exceeds a preset threshold value, the required gap angle correction value is calculated to make the electric field distribution tend to be uniform. The gap angle adjustment is realized by changing the relative inclination angle between the electrodes, the electrode surface roughness measurement value is obtained, and according to the proportional relationship between the roughness value and the local electric field intensity, the roughness is reduced to a target value to reduce the electric field concentration. By using the gap angle correction value and the target roughness value, in combination with the original electrode spacing data, a geometric structure configuration parameter set containing the corrected electrode spacing, the relative inclination angle and the surface roughness parameters is generated, the electric field intensity of the high-risk region is reduced to a safe range by adjusting these parameters, and an optimized geometric parameter configuration scheme is obtained.

[0067] Exemplarily, in the risk level classification of lightning protection equipment, the peak value of electric field intensity is the most direct basis for judgment.

[0068] Specifically, the first threshold is usually set at about 50% of the air breakdown field strength, and the second threshold is set at about 80%. This grading method is based on the relationship between electric field intensity and breakdown probability. When the electric field intensity approaches the breakdown field strength, the ionization probability of air molecules increases sharply, and the risk of forming an electric arc increases significantly. Although there is an electric field in the low-risk area, the intensity is much lower than the breakdown threshold, and no electric arc will be generated during normal operation; partial discharge may occur in the medium-risk area under certain conditions; and electric arc breakdown is extremely easy to occur in the high-risk area.

[0069] It should be noted that the calculation of energy density is crucial for evaluating the degree of arc hazard. The bifurcated energy distribution value reflects the total energy released by the arc in space, and the energy density represents the concentration of energy per unit volume. By dividing the total energy by the volume of the region, the average energy density can be obtained. The product of this parameter and the deflection angle forms a comprehensive adjustment parameter, which takes into account both the intensity of energy and the spatial distribution characteristics of the arc. The larger the deflection angle, the stronger the instability of the arc; the higher the energy density, the more serious the local thermal effect. Adjusting the gap angle is an effective means to improve the electric field distribution.

[0070] In one possible implementation, when the two electrodes are completely parallel, the electric field is relatively uniform in the middle of the gap, but there is a clear edge effect at the edges of the electrodes. By adjusting the relative inclination angle between the electrodes, the gap can be made to have a certain conical distribution, which can change the spatial distribution pattern of the electric field. The determination of the inclination angle needs to consider the gap distance, electrode shape and working voltage comprehensively. Proper inclination can disperse the electric field intensity that was originally concentrated in certain areas, reducing the local electric field peak value. The surface roughness of the electrode is closely related to the electric field concentration phenomenon. On a microscopic level, rough surfaces have many small protrusions and depressions, and these microstructures can cause a significant enhancement of the local electric field. The curvature radius at the protrusions is small, and according to electrostatic principles, the larger the curvature, the higher the electric field intensity. The roughness value is usually represented by the average deviation, and when the roughness decreases from microns to nanometers, the local electric field enhancement effect can be reduced by several times.

[0071] Preferably, the development of the geometric parameter configuration scheme needs to consider the mutual influence of multiple factors. The adjustment of the electrode spacing directly affects the overall electric field strength, and an increase in the spacing will reduce the average field strength but may increase the device volume; the setting of the inclination angle changes the electric field distribution pattern, and excessive inclination may lead to new electric field concentration points; the control of surface roughness involves processing technology and cost. These parameters are not independent, but are coupled to affect the final electric field distribution.

[0072] Step S106, according to the optimized geometric parameter configuration scheme, the inner gap structure is adjusted in real time, and the adjusted branch number is recalculated. If it is still greater than the threshold value, the gap width change and the electrode material conductivity parameter corresponding to each branch path are adjusted synchronously to obtain a multi-path adaptive geometric structure.

[0073] According to the electrode spacing, inclination angle and surface roughness parameters in the optimized geometric parameter configuration scheme, the relative position of the electrode in the inner gap structure is changed through the mechanical adjustment device, the adjusted arc development image data is collected, the branch point position and branch direction of the arc channel are re-identified, and the adjusted branch number is counted. If the branch number is still greater than the preset threshold value, the spatial coordinate sequence of each branch path is obtained, the electric field intensity distribution value around each path is calculated, and the gap width adjustment amount of each path corresponding position is determined according to the constraint relationship that the product of the electric field intensity value and the gap width is constant. When the electric field intensity is higher than the average value, the gap width at this position is increased, and when the electric field intensity is lower than the average value, the gap width is reduced. The gap width adjustment amount data is used to configure low-conductivity electrode material in the path area with increased width to increase the resistance, and high-conductivity electrode material in the path area with reduced width to reduce the resistance, so that the current density of each branch path tends to be balanced according to the distribution law that the current is inversely proportional to the resistance in the parallel circuit, and a differentiated material configuration and gap width distribution for multiple branch paths are formed, thereby obtaining a multi-path adaptive geometric structure.

[0074] For example, the application of the mechanical adjustment device in the lightning protection equipment embodies the importance of precise control.

[0075] Specifically, such a device usually adopts a lead screw mechanism driven by a stepper motor, which can realize micron-level position adjustment. When the electrode spacing needs to be changed, the control signal drives the stepper motor to rotate by a certain angle, and the rotary motion is converted into linear motion through the lead screw to push the electrode to the target position. The adjustment of the inclination angle is realized through multi-axis linkage. Each electrode is installed on an independently adjustable support, and the overall angle is changed by coordinating the movement of each support.

[0076] It should be noted that the constraint relationship that the product of the electric field intensity and the gap width remains constant is derived from Gauss's law. In a parallel plate electrode structure, when the charge quantity is fixed, the electric field intensity is inversely proportional to the distance between the plates. This means that the narrower the gap, the stronger the electric field, and the more likely it is to break down. By actively adjusting the gap width, the originally uneven electric field distribution can be made more uniform. When it is detected that the electric field intensity in a certain area is too high, the gap width at that position is increased, and the electric field intensity is correspondingly reduced; on the contrary, in the area where the electric field is weak, the gap width is appropriately reduced to increase the electric field intensity in that area. The difference in conductivity of the electrode material provides another means of regulating the current distribution.

[0077] In one possible implementation, high-conductivity materials such as copper or aluminum have a lower resistivity, while the resistivity of materials such as stainless steel or tungsten is relatively high. When the arc generates multiple branched paths, each path can be considered as a branch of a parallel circuit. According to Ohm's law and Kirchhoff's law, the distribution of current in each branch is inversely proportional to the resistance of the branch. By configuring materials with different conductivities in different paths, the resistance of each path can be artificially adjusted, thereby controlling the distribution of current. The combined adjustment mechanism of gap width adjustment and material selection forms a comprehensive control mechanism. The resistance of a path itself increases as the gap width increases, and if low-conductivity materials are configured, the resistance is further increased, and the current flowing through the path is significantly reduced. This dual adjustment mechanism is more effective than a single means.

[0078] For example, a branched path originally carries too much current. By increasing the gap width, the current can be reduced by 20%. After replacing it with a low-conductivity material, the current can be further reduced by 30%, and the overall effect is a 50% reduction in current.

[0079] Preferably, the formation of the multi-path adaptive geometry is a dynamic optimization process. After the initial adjustment, the current distribution of each path needs to be re-measured, and if there is still imbalance, a second adjustment can be made. This adaptive structure can flexibly respond to the actual development of the arc, and different branched patterns correspond to different geometric configurations. The structure formed has a reasonable electric field distribution and current carrying capacity on each possible arc path, improving the reliability of the lightning protection device under complex working conditions.

[0080] Step S107, through the multi-path adaptive geometry, the adjusted plasma density distribution uniformity index is recalculated, the arc temperature gradient uneven area is compensated and adjusted, and a stable plasma density distribution state is obtained.

[0081] The gap width and material conductivity configuration data of the multi-path adaptive geometry are used to recalculate the plasma density values of each spatial position according to the adjusted current distribution, the ratio of the standard deviation to the average of all sampling point density values is calculated as the density distribution uniformity index, and the spatial positions whose density values deviate from the average by more than a threshold value are recorded. Based on the density value data of the deviated positions, the plasma temperature values corresponding to each position are calculated through the exponential relationship between temperature and ionization degree in the Saha ionization equation, the temperature difference between adjacent positions is determined by dividing the temperature gradient by the position interval, and the continuous region whose temperature gradient exceeds a preset threshold is identified as a non-uniform region. For the temperature gradient data of the non-uniform region, an optimization problem is constructed with the temperature variance minimization as the objective function, and the gradient descent algorithm is used to iteratively adjust the electric field strength values of each position. In each iteration, the electric field strength is updated in the negative direction of the temperature gradient, and the electric field is adjusted by adjusting the power supply voltage or changing the local electrode spacing. When the plasma density difference between adjacent regions is less than a preset threshold, the iteration is stopped, and a stable plasma density distribution state is obtained.

[0082] For example, the calculation of the density distribution uniformity index provides a quantitative basis for subsequent optimization.

[0083] Specifically, the standard deviation reflects the dispersion of data. When the plasma density is unevenly distributed in space, the deviation of each point density value from the average will cause the standard deviation to increase. The coefficient of variation obtained by dividing the standard deviation by the average is a dimensionless parameter that can objectively compare the uniformity under different conditions. When the coefficient of variation exceeds 0.3, it is generally considered that there is significant non-uniformity and adjustment is needed.

[0084] It should be noted that the Saha ionization equation reveals the quantitative relationship between plasma temperature and ionization degree. Under thermal equilibrium conditions, the higher the temperature, the more kinetic energy the gas molecules obtain, and the probability of collision ionization increases accordingly. This relationship exhibits exponential characteristics, and small changes in temperature can cause significant changes in ionization degree. Conversely, the measured plasma density can be used to calculate the corresponding temperature value. High-density regions correspond to higher ionization degree and temperature, while low-density regions have relatively lower temperatures. The calculation of the temperature gradient is similar to that of the electric field gradient, reflecting the rate of change of temperature in space.

[0085] In one possible implementation, the temperature difference between two adjacent points divided by the distance between them gives the temperature gradient in that direction. In three-dimensional space, the gradient components in each direction need to be considered. A large temperature gradient means that there is a strong heat exchange, which will lead to unstable flow and energy loss of the plasma. Identifying these high gradient areas is a prerequisite for achieving uniformity regulation. The core of the algorithm is to adjust the parameters in the direction of the fastest descent along the objective function. With the goal of minimizing the temperature variance, it means that the temperature of each region should be as close to the average value as possible. In each iteration, the algorithm calculates the variance corresponding to the current temperature distribution, and then determines the adjustment direction and amplitude of the electric field strength at each location. Increasing the electric field strength will increase the plasma density and temperature at that location, and vice versa.

[0086] Preferably, the implementation of electric field adjustment can be achieved in various ways. Adjusting the power supply voltage is the most direct method, and increasing the voltage will enhance the electric field as a whole, but this method lacks local control ability. Changing the local electrode spacing can achieve fine adjustment, and through the aforementioned mechanical adjustment device, the gap width of different regions can be independently controlled. Small adjustment amounts can produce significant changes in the electric field, and this sensitivity requires the control system to have high precision. The convergence criterion of the iterative process ensures the stability of the final state. The density difference between adjacent regions reflects the uniformity of the spatial distribution, and when the density difference of all adjacent regions is less than the set threshold, it means that a good uniform state has been reached. In this state, the temperature distribution of the plasma also tends to be uniform, reducing local overheating and energy concentration, and improving the overall performance and service life of the lightning protection equipment.

[0087] Step S108, based on the density uniformity region boundary and density gradient change rule determined by the stable plasma density distribution state, the migration trajectory of the arc root attachment point is limited, combined with the temperature and pressure change properties of the arc root to reduce the random migration amplitude of the attachment point, and the controllable arc root attachment behavior is obtained.

[0088] Based on the stable plasma density distribution state, a continuous spatial region with a density value change less than a preset threshold is identified, the outer boundary coordinates of the region are determined as the density uniform region boundary, the density difference value of each point inside and outside the boundary to the distance of the point to the boundary is calculated, and the data of the ratio of the density gradient change with the position are recorded as the density gradient change law. According to the density uniform region boundary and the gradient change law, the boundary position is set as the constraint range of the attachment point migration, when the attachment point is close to the boundary, the electrode spacing outside the boundary is increased to reduce the electric field intensity in the region, so that the attachment point tends to stay in the uniform region, the temperature value and the pressure value of the attachment point are obtained by the thermocouple and the pressure sensor, the temperature change amount and the pressure change amount per unit time are calculated, and the change amount is associated with the displacement distance of the attachment point in the same period. Using the association data of the temperature change amount, the pressure change amount and the displacement distance, when the temperature change rate or the pressure change rate exceeds the preset threshold, the overall electric field intensity is reduced by reducing the power supply voltage, the driving force of the arc root is weakened, the maximum displacement distance of the attachment point per unit time is limited, the random migration amplitude is controlled within a predetermined range, and a controllable arc root attachment behavior is obtained.

[0089] For example, the determination of the density uniform region boundary provides a key reference for arc control.

[0090] Specifically, when the plasma density remains relatively stable in a certain region, the electric field distribution and temperature field in the region are also relatively uniform. By identifying the continuous region with a density change less than a threshold, the spatial range suitable for the stable existence of the arc can be circled. The density gradient calculation of the boundary position reveals the transition characteristics from the uniform region to the non-uniform region, and this gradient information is of great significance for predicting the motion trend of the attachment point.

[0091] It should be noted that the physical mechanism of setting the boundary as a constraint range is based on the stability characteristics of the arc. The arc tends to develop in the path with the minimum energy loss, and the density uniform region just provides such conditions. When the attachment point approaches the boundary, the high density gradient outside the boundary will produce additional resistance. By actively increasing the electrode spacing outside the boundary, the electric field intensity in the region can be further reduced, forming an "electric field barrier" to make it difficult for the attachment point to cross the boundary and enter the unstable region. The application of thermocouples and pressure sensors realizes real-time monitoring of the state of the attachment point.

[0092] In one possible implementation, the thermocouple acquires temperature values by measuring the thermoelectric potential of the contact points, with a response time of milliseconds. The pressure sensor measures the local pressure by the piezoelectric effect or the principle of capacitance change. The rate of change of these two parameters directly reflects the activity level of the arc. A sharp rise in temperature means a concentrated release of energy, and a sudden change in pressure indicates rapid expansion or contraction of the plasma. The correlation between temperature and pressure changes and the displacement of the attachment point reveals the driving mechanism of the arc movement. When the local temperature rises, the plasma density in this area increases, and the resulting pressure gradient will push the attachment point to move in the direction of lower temperature. This spontaneous migration process, if not controlled, will lead to random walking of the attachment point, increasing the risk of equipment damage. By establishing a quantitative relationship between the rate of change and the displacement distance, the movement trend of the attachment point can be predicted.

[0093] Preferably, the regulation of electric field intensity provides an effective intervention means. Reducing the supply voltage is a global regulation method that reduces the electric field intensity in the entire gap, thereby reducing the electric force driving the arc movement. When the rate of change of temperature or pressure exceeds the threshold value, the control system automatically reduces the voltage, causing the arc to enter a low-energy state. In this state, the random motion of the attachment point is suppressed, and the migration speed and amplitude are effectively controlled. Controllable arc root attachment behavior means that the motion trajectory of the attachment point is predictable and the migration range is limited. This control capability significantly improves the reliability of the lightning protection device. The attachment point no longer randomly walks to the weak parts of the device, but is limited to a pre-designed safe area.

[0094] The present application provides a lightning protection effect evaluation device based on an internal gap design, mainly comprising:

[0095] An arc spatial coordinate acquisition module is used to acquire the spatial coordinate data of the arc channel in the internal gap of the lightning protection device, to obtain the arc offset angle and bifurcation position by coordinate difference calculation, to calculate the arc channel length and bifurcation branch number, and to obtain the spatial distribution state parameters of the arc channel;

[0096] An arc morphology analysis module is used to calculate the plasma density distribution according to the spatial distribution parameters, analyze the bifurcation energy distribution, identify the coordinates of the electric field concentration area, and obtain the plasma density distribution map if the offset angle or bifurcation number exceeds the threshold value;

[0097] A plasma density calculation module is used to analyze the density gradient trend of the plasma density distribution map, determine the current position coordinates of the arc root attachment point, and obtain the migration path of the attachment point in combination with the time sequence coordinate change trajectory analysis;

[0098] An attachment point trajectory analysis module is configured to model and analyze the electric field intensity and gradient distribution at different positions of the inner gap according to the attachment point migration path to obtain electric field distribution characteristic parameters. If the attachment point migrates to an electric field concentration area, the area is marked as a high-risk area, and an electric field distribution risk assessment result is obtained.

[0099] An electric field risk assessment module is configured to determine the distribution range and risk level of the high-risk area according to the electric field distribution risk assessment result, adjust the gap angle deviation in combination with the electric arc deflection angle and the bifurcation energy distribution for the high-risk arc-extinguishing area, and optimize the inner gap geometric structure configuration in combination with the electrode surface roughness to obtain an optimized geometric parameter configuration scheme.

[0100] A geometric structure optimization module is configured to real-time adjust the inner gap structure according to the optimized geometric parameter configuration scheme, and recalculate to obtain an adjusted bifurcation branch number. If the bifurcation branch number is still greater than a threshold value, the gap width variation and electrode material conductivity parameters corresponding to each bifurcation path are adjusted synchronously to obtain a multi-path adaptive geometric structure.

[0101] A multi-path adjustment module is configured to recalculate the adjusted plasma density distribution uniformity index through the multi-path adaptive geometric structure, compensate and adjust the arc temperature gradient non-uniform area, and obtain a stable plasma density distribution state.

[0102] An arc stable control module is configured to determine the density uniform area boundary and density gradient variation law based on the stable plasma density distribution state, limit the migration trajectory of the arc root attachment point, reduce the random migration amplitude of the attachment point in combination with the arc root temperature and pressure change attributes, and obtain a controllable arc root attachment behavior.

[0103] The above only describes the preferred embodiments of one or more embodiments of the present specification, and does not limit one or more embodiments of the present specification. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of one or more embodiments of the present specification should be included in the protection scope of one or more embodiments of the present specification.

Claims

1. A method for evaluating lightning protection effectiveness based on internal gap design, characterized in that, The method includes: The spatial coordinate data of the arc channel in the gap of the lightning protection equipment are obtained. The arc offset angle and bifurcation position are calculated by the coordinate difference. The arc channel length and the number of bifurcation branches are calculated to obtain the spatial distribution state parameters of the arc channel. Based on the spatial distribution state parameters, the plasma density distribution is calculated, the bifurcation energy distribution is analyzed, and the coordinates of the electric field concentration area are identified to obtain the plasma density distribution map. The density gradient change trend of the plasma density distribution map is analyzed to determine the current position coordinates of the arc root attachment point. Combined with the temporal coordinate change trajectory analysis, the migration path of the attachment point is obtained. Based on the attachment point migration path, the electric field intensity and gradient distribution at different positions in the gap are modeled and analyzed to obtain the electric field distribution characteristic parameters. The electric field concentration area is marked as a high-risk area to obtain the electric field distribution risk assessment result. The risk assessment results determine the distribution range and risk level of high-risk areas. Adjusting the gap angle deviation and electrode surface roughness yields an optimized geometric parameter configuration scheme. Based on this optimized scheme, the internal gap structure is adjusted, the number of bifurcations is recalculated, and the gap width and electrode material conductivity parameters corresponding to each bifurcation path are simultaneously adjusted to obtain a multi-path adaptive geometry. The plasma density distribution uniformity index is recalculated using this multi-path adaptive geometry, and the non-uniform arc temperature gradient region is adjusted to obtain a stable plasma density distribution state. Based on this stable plasma density distribution state, the boundary of the density uniform region and the density gradient variation law are determined, limiting the migration trajectory of the arc root attachment point. The temperature and pressure variation attributes of the attachment point are adjusted to obtain controllable arc root attachment behavior.

2. The lightning protection effect evaluation method based on internal gap design according to claim 1, characterized in that, The process involves acquiring spatial coordinate data of the arc channel within the gap of the lightning protection equipment, calculating the arc offset angle and bifurcation position using coordinate differences, calculating the arc channel length and the number of bifurcations, and obtaining the spatial distribution parameters of the arc channel, including: The process involves acquiring the three-dimensional spatial coordinate data of each sampling point on the arc channel within the gap of the lightning protection equipment, extracting the two-dimensional projected coordinates of the arc channel, reconstructing the three-dimensional spatial coordinates, calculating the coordinate difference between adjacent sampling points, and obtaining the direction vector of each arc channel segment. Based on the direction vectors of each arc channel segment, the angle between adjacent channel segments is calculated to determine the bifurcation point location. The three-dimensional coordinates of the bifurcation point are recorded, the number of branches is counted, and the offset angle of each branch relative to the main channel is calculated. Based on the sum of the three-dimensional spatial coordinates and the Euclidean distance between adjacent sampling points, the length of the main arc channel and the length of the branch channels are obtained. Finally, by combining the bifurcation point coordinates, the number of branches, the offset angle, and the channel length, the spatial distribution state parameters of the arc channel are determined.

3. The lightning protection effect evaluation method based on internal gap design according to claim 1, characterized in that, The process of calculating the plasma density distribution based on the spatial distribution state parameters, analyzing the bifurcation energy distribution, identifying the coordinates of the electric field concentration region, and obtaining the plasma density distribution map includes: Based on the three-dimensional coordinates of the bifurcation points and the channel length in the spatial distribution state parameters, the cross-sectional area and volume of each channel segment are calculated. The initial current density value is obtained by dividing the arc current value by the channel volume. The plasma density value of each channel segment is determined according to the correspondence between the current density and the plasma density. Based on the plasma density value and the current density value, the current value of each bifurcation channel is allocated, and the energy value per unit length of each branch is calculated to obtain the bifurcation energy distribution value. The energy density is calculated using the bifurcation energy distribution value. Spatial regions with energy densities exceeding a threshold are identified as electric field concentration regions. The coordinates of the center point of the electric field concentration region are recorded, and continuous density field data is generated using a three-dimensional linear interpolation method to construct a plasma density distribution map.

4. The lightning protection effect evaluation method based on internal gap design according to claim 1, characterized in that, The process of analyzing the density gradient change trend of the plasma density distribution spectrum to determine the current position coordinates of the arc root attachment point, and combining this with the temporal coordinate change trajectory analysis to obtain the attachment point migration path, includes: The density gradient is calculated for each spatial point in the plasma density distribution map. Neighboring points in six orthogonal directions are selected, and the density difference is calculated and divided by the distance between points to obtain the gradient components in each direction. A three-dimensional gradient vector is synthesized, and continuous regions with gradient values ​​exceeding a threshold are identified as candidate regions for the arc root. Density value changes are tracked along the gradient direction, and points where the density is locally maximum and the gradient component approaches zero are identified as arc root attachment points. The three-dimensional coordinates of the arc root attachment points are recorded. The plasma density distribution maps at different times are processed repeatedly to obtain the attachment point coordinates at each time, forming a time-series coordinate dataset. The coordinates at each time are connected to generate a continuous trajectory curve, thus obtaining the attachment point migration path.

5. The lightning protection effect evaluation method based on internal gap design according to claim 1, characterized in that, The process involves modeling and analyzing the electric field intensity and gradient distribution at different locations within the internal gap based on the migration path of the attachment point, obtaining characteristic parameters of the electric field distribution, marking areas of concentrated electric field as high-risk areas, and obtaining an electric field distribution risk assessment result, including: Based on the coordinate sequence along the attachment point migration path, combined with gap geometry and electrode position data, a grid is divided, and the potential value of each grid node is calculated to obtain the electric field strength value and gradient data. The maximum value, average value, and standard deviation of the electric field strength value are extracted, the distribution uniformity is calculated, and areas where the electric field strength exceeds the threshold are identified as electric field concentration areas. It is determined whether the position on the attachment point migration path enters the electric field concentration area, high-risk areas are marked, and the coordinates, volume, and peak electric field strength of the high-risk areas are recorded to generate an electric field distribution risk assessment result.

6. The lightning protection effect evaluation method based on internal gap design according to claim 1, characterized in that, The process of determining the distribution range and risk level of high-risk areas based on the electric field distribution risk assessment results, adjusting the gap angle deviation and electrode surface roughness, and obtaining an optimized geometric parameter configuration scheme includes: Based on the coordinates of high-risk areas and peak electric field intensity in the electric field distribution risk assessment results, risk levels are classified, and the spatial distribution range boundaries of each level are determined. The arc offset angle and bifurcation energy distribution values ​​within the high-risk areas are obtained, the energy density is calculated, and the gap angle correction value is determined. The relative tilt angle between electrodes is adjusted according to the arc offset angle and energy density, and adjusted to the target value according to the electrode surface roughness value. Combining the corrected electrode spacing, tilt angle, and roughness parameters, an optimized geometric parameter configuration scheme is generated.

7. The lightning protection effect evaluation method based on internal gap design according to claim 1, characterized in that, The process of adjusting the internal gap structure according to the optimized geometric parameter configuration scheme, recalculating the number of bifurcations, and simultaneously adjusting the gap width and electrode material conductivity parameters corresponding to each bifurcation path to obtain a multi-path adaptive geometry includes: Based on the electrode spacing, tilt angle, and roughness parameters in the optimized geometric parameter configuration scheme, the relative positions of the electrodes are adjusted, the adjusted arc development data is collected, and the bifurcation point positions and the number of branches are re-identified. If the number of bifurcation branches exceeds the threshold, the electric field intensity distribution around each bifurcation path is calculated, the gap width is adjusted according to the electric field intensity value, and differentiated conductivity electrode materials are configured to balance the current density of each bifurcation path, thereby generating a multi-path adaptive geometry.

8. The lightning protection effect evaluation method based on internal gap design according to claim 1, characterized in that, The step of recalculating the plasma density distribution uniformity index through the multi-path adaptive geometry, adjusting the non-uniform region of the arc temperature gradient, and obtaining a stable plasma density distribution state includes: Using the gap width and material conductivity data of the multipath adaptive geometry, the plasma density value at each spatial location is recalculated, the density uniformity index is calculated, and the locations where the density value deviates from the average value by more than a threshold are recorded. The temperature value and temperature gradient are calculated based on the plasma density value, and the region where the temperature gradient exceeds the threshold is identified. For the temperature gradient, the electric field strength value is iteratively adjusted, and the local electrode spacing is adjusted. When the density difference is less than the threshold, a stable plasma density distribution state is obtained.

9. The lightning protection effect evaluation method based on internal gap design according to claim 1, characterized in that, The process of determining the boundary of the density-uniform region and the density gradient variation law based on the stable plasma density distribution state, restricting the migration trajectory of the arc root attachment point, and adjusting the temperature and pressure variation properties of the attachment point to obtain controllable arc root attachment behavior includes: Based on the stable plasma density distribution state, regions with density changes less than a threshold are identified, their boundary coordinates are determined, and the density gradient change law is calculated. According to the boundary of the uniform density region, the attachment point migration constraint range is set, the electrode spacing outside the boundary is increased, and the electric field strength is reduced to obtain controllable arc root attachment behavior.

10. A lightning protection effect evaluation device based on internal gap design, characterized in that, The system includes: The arc spatial coordinate acquisition module is used to acquire the spatial coordinate data of the arc channel in the gap inside the lightning protection equipment. It calculates the arc offset angle and bifurcation position through the coordinate difference, calculates the arc channel length and the number of bifurcation branches, and obtains the spatial distribution state parameters of the arc channel. The arc morphology analysis module is used to calculate the plasma density distribution based on the spatial distribution state parameters, analyze the bifurcation energy distribution, identify the coordinates of the electric field concentration region, and obtain the plasma density distribution map. The plasma density calculation module is used to analyze the density gradient change trend of the plasma density distribution map, determine the current position coordinates of the attachment point at the root of the arc, and obtain the migration path of the attachment point by combining the time-series coordinate change trajectory analysis. The attachment point trajectory analysis module is used to model and analyze the electric field intensity and gradient distribution at different locations within the gap based on the migration path of the attachment point, obtain electric field distribution characteristic parameters, mark the electric field concentration area as a high-risk area, and obtain the electric field distribution risk assessment result. The electric field risk assessment module is used to determine the distribution range and risk level of high-risk areas based on the electric field distribution risk assessment results, adjust the gap angle deviation and electrode surface roughness, and obtain an optimized geometric parameter configuration scheme. The geometric structure optimization module is used to adjust the internal gap structure according to the optimized geometric parameter configuration scheme, recalculate the number of bifurcations, and synchronously adjust the gap width and electrode material conductivity parameters corresponding to each bifurcation path to obtain a multi-path adaptive geometric structure. The multi-path adjustment module is used to recalculate the plasma density distribution uniformity index through the multi-path adaptive geometry, adjust the non-uniform region of the arc temperature gradient, and obtain a stable plasma density distribution state. The arc stabilization control module is used to determine the boundary of the density uniform region and the density gradient variation law based on the stable plasma density distribution state, restrict the migration trajectory of the arc root attachment point, and adjust the temperature and pressure change properties of the attachment point to obtain controllable arc root attachment behavior.

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