Optimization method for double-ring voltage grading ring of high-voltage end of power equipment in high-altitude area

Abstract

The application provides a high-altitude area high-voltage end double-ring grading ring optimization method for power equipment, which comprises the following steps: S1. geometric modeling of the power equipment and the double-ring grading ring; S2. particle representation of the geometric parameter combination to obtain an initial particle group, and then calculation of the maximum electric field intensity value E i‑max1 of the power equipment surface under the geometric parameter combination corresponding to the initial particle group i‑max2 ; S3. calculation of the fitness function value Fitness; S4. search for individual extreme value P best and group extreme value G best , and updating of the particle speed and position based on the individual extreme value and the group extreme value to obtain an updated particle group; S5. judgment of whether the group extreme value is stable; and S6. verification of whether the maximum electric field intensity of the double-ring grading ring along the surface corresponding to the stable group extreme value in step S5 is less than the corrected double-ring grading ring corona onset electric field intensity.

Description

Technical Field

[0001] This invention relates to the field of voltage equalization ring optimization, and more particularly to a method for optimizing a double-ring voltage equalization ring at the high-voltage end of power equipment in high-altitude areas. Background Technology

[0002] With the continuous advancement of ultra-high voltage (UHV) projects and the rapid development of power grid construction, electromagnetic problems surrounding power equipment are becoming increasingly prominent, and phenomena such as discharge, flashover, and corona in power grid accidents are accounting for a growing proportion. The emergence of equalizing rings has alleviated these problems. Their mechanism involves utilizing the electromagnetic effect of electrical conductors to stretch the concentrated electric field around the power equipment outwards, thereby reducing the electric field strength per unit area and making the electric field distribution more uniform. This prevents corona and flashover, and they have become an indispensable part of ultra-high voltage (UHV) transmission systems.

[0003] If the equalizing ring is to play a full role in optimizing the electric field distribution of power equipment, the rational design of the equalizing ring structure is particularly important. At present, the design of the geometric parameters of the equalizing ring and the finding of the optimal combination of geometric parameters are mainly done by exhaustive search. Finding the optimal combination of geometric parameters by exhaustive search not only requires a lot of time, but also involves complicated manual operation.

[0004] Therefore, in order to solve the above-mentioned technical problems, it is urgent to propose a new technical approach. Summary of the Invention

[0005] In view of this, the present invention provides an optimization design method for a double-ring equalizing ring at the high-voltage end of power equipment in high-altitude areas. Under the premise of fully considering the influence of environmental factors in high-altitude areas on the electrical characteristics of the power equipment itself, the modern intelligent algorithm of particle swarm optimization (PSO) is applied to the optimization design process of the core geometric parameters of the double-ring equalizing ring. This greatly reduces the time and manpower costs in the parameter optimization process of the double-ring equalizing ring, and standardizes and efficiencies the process of scientifically designing the double-ring equalizing ring.

[0006] This invention provides an optimization method for a dual-ring voltage equalization ring at the high-voltage end of power equipment in high-altitude areas, comprising the following steps:

[0007] S1. Perform geometric modeling of the power equipment and the double-ring equalizing ring;

[0008] S2. The physical geometric model is transformed into a finite element method (FEM) model. Electrical boundary conditions are then applied to the FEM model. The combination of geometric parameters is represented by particles to obtain an initial particle swarm. Finally, the maximum electric field intensity E on the surface of the power equipment under the geometric parameter combination corresponding to the initial particle swarm is calculated. i-max1 The maximum electric field strength E along the surface of the equalizing ring i-max2 ;

[0009] S3. Based on the maximum electric field strength value E on the surface of the power equipment i-max1 The maximum electric field strength E along the surface of the equalizing ring i-max2 and the corrected corona induction electric field strength E 2H Calculate the fitness function value (Fitness);

[0010] S4. Find the individual extreme value P based on the fitness function value. best and the group extreme value G best The velocity and position of particles are updated based on individual and group extreme values ​​to obtain the updated particle swarm.

[0011] S5. Determine whether the population extremum is stable. If so, obtain the maximum electric field intensity along the surface of the double-ring equalizing ring corresponding to the stable population extremum and the combination of geometric parameters of the double-ring equalizing ring corresponding to the stable population extremum. If not, use the updated particle swarm as the initial particle swarm for the new round of iteration and repeat steps S2-S4 until the population extremum is stable.

[0012] S6. Verify whether the maximum electric field intensity along the surface of the double-ring equalizing ring corresponding to the stable population extremum in step S5 is less than the corona initiation electric field intensity of the double-ring equalizing ring after correction in step S3. If yes, determine the particle swarm corresponding to the stable population extremum and combine the geometric parameters of the double-ring equalizing ring corresponding to the particle swarm corresponding to the stable population extremum into the optimal geometric parameters. If no, update the particle swarm corresponding to the stable population extremum in step S5, use the updated particle swarm as the initial particle swarm, and repeat steps S2-S5 until the optimal geometric parameters less than the corona initiation electric field intensity of the double-ring equalizing ring are determined.

[0013] Furthermore, in step S1, the power equipment and the double-ring equalizing ring are geometrically modeled using the following method:

[0014] S11. Collect the structural geometric parameters, electrical parameters, and environmental parameters of the equipment's location;

[0015] S12. Perform full-scale structural modeling of specific power equipment;

[0016] S13. Based on the structural geometric parameters of the power equipment collected in step S11, and combined with the local experience in the operation and installation of similar or identical equipment, determine the range of values ​​for the core geometric parameters of the double-ring equalizing ring: ring diameter, pipe diameter, and center distance between the two rings.

[0017] S14. Within the range of values ​​for the core geometric parameters of the double-ring equalizing ring—ring diameter, pipe diameter, and center distance between the two rings—determine Q sets of geometric parameter combinations as the initial particle swarm X = (X1, X2, ..., X...). QThe ring diameter, pipe diameter, and center distance between the two rings are defined as design variables. Then, the positions of the Q-group particles after initialization are assigned to the design variables, and parametric modeling is performed based on these Q-group particle positions.

[0018] Furthermore, the particle positions are initialized using the following method:

[0019] Initial particle swarm X = (X1, X2, ..., X Q Each particle in the vector represents a three-dimensional vector X. i =[X i1 ,X i2 ,X i3 (i = 1, 2, 3, ..., Q), X i This represents the position of the i-th particle in three-dimensional space. The position and velocity of the particle are initialized using the following formula:

[0020]

[0021]

[0022] Where i is the particle's number within the population, m = 1, 2, 3, representing the three geometric parameters of the equalizing ring: ring diameter, pipe diameter, and center-to-center distance between the two rings, respectively, and D m U represents the lower limit of the values ​​in the combination of geometric parameters. m This indicates the upper limit of the possible values ​​in a combination of geometric parameters.

[0023] Furthermore, the electrical parameters of the power equipment include: the maximum operating voltage and the maximum permissible electric field strength E1 on the surface under the maximum operating voltage, and the environmental parameters include: the altitude, temperature, air pressure and humidity of the equipment's location.

[0024] Furthermore, in step S2, the physical geometric model is transformed into a finite element calculation model using the following method:

[0025] Artificial boundaries are set at a distance from the power equipment and the double-ring equalizing ring model to transform the open domain space near the power equipment and the double-ring equalizing ring into a finite domain. The power equipment, the double-ring equalizing ring and the finite domain are meshed, and the physical geometric model is converted into a finite element calculation model.

[0026] Furthermore, in step S2, the maximum electric field strength value on the surface of the power equipment and the maximum electric field strength value along the surface of the equalizing ring are obtained by the following method:

[0027] The potential of the artificial boundary is set to 0, and the highest operating voltage collected in step S1 is applied to the high-voltage end of the conductor of the power equipment within the artificial boundary. The electric field and potential in the finite domain are solved using the finite element method to obtain the spatial distribution of the electric field and potential.

[0028] Within the solution domain, the electric field is solved:

[0029]

[0030]

[0031] Within the solution domain, the potential is solved:

[0032] N(D1-D2)=0

[0033] U1=U

[0034] U0 = 0

[0035] in, Here, ρ is the vector differential operator, ρ is the free charge density, E is the electric field intensity in the solution domain, and ε0 and ε r Let N be the vacuum permittivity and the relative permittivity of the medium, respectively; N be the normal vector perpendicular to the interface; D1 be the electric displacement perpendicular to the interface within the medium inside the artificial boundary; D2 be the electric displacement perpendicular to the interface within the medium outside the artificial boundary; U1 be the potential of the high-voltage conductor side; U be the specific potential value of the high-voltage conductor of the power equipment; and U0 be the finite boundary potential, which is the artificial boundary potential of 0. Based on the finite element calculation model, the maximum electric field intensity E on the surface of the power equipment under the geometric parameter combination represented by the initial particle swarm X is obtained. i-max1 (i=1,2,3,…,Q) and the maximum electric field intensity E along the surface of the double-ring equalizing ring. i-max2 (i = 1, 2, 3, ..., Q).

[0036] Furthermore, in step S3, the fitness function value is calculated using the following method:

[0037]

[0038] Where ω1 and ω2 are weight values, assigned by the decision-maker according to the weighting method, i represents the i-th particle, Fitness represents the fitness function value, and E i-max1 E represents the maximum electric field strength on the surface of electrical equipment. i-max2 E represents the maximum electric field strength along the surface of the double-ring equalizing ring. 1H This represents the result of altitude correction for the maximum permissible electric field strength E1 on the surface under the highest operating voltage. 2H The result is the altitude-corrected value of the initiation electric field strength E2 specified for the double-ring equalization ring.

[0039] Furthermore, the electric field strength is corrected for altitude using the following method:

[0040]

[0041] Ka =K d ×K k

[0042]

[0043] K h =K w

[0044] Among them, E kH E is the corrected electric field strength. k K represents the electric field strength before correction. a K is the altitude correction factor. d For air density correction factor, δ is relative air density, n is relative air density index, P is actual atmospheric pressure, t is actual air pressure temperature, P0 is atmospheric pressure under reference atmospheric pressure conditions, t0 is temperature under reference atmospheric pressure conditions, w is correction index, and K depends on the test voltage type.

[0045] Furthermore, in step S4, the velocity and position of the particle swarm are updated using the following method:

[0046] Individual extreme value P best The population extreme value G represents the position with the best calculated fitness value among the positions experienced by a particle. best This indicates that all particles have found the optimal fitness value. The velocity and position of the particle swarm are updated based on the individual and swarm extreme values. The update formula is:

[0047]

[0048]

[0049] in, Let represent the velocity of the i-th particle in the (S+1)-th iteration, c1 and c2 represent learning factors (non-negative constants), and r1 and r2 represent random numbers. This represents the position of the i-th particle in the (S+1)-th iteration.

[0050] Furthermore, in step S5, the population is considered stable when the population extreme value simultaneously satisfies the following three conditions:

[0051]

[0052]

[0053]

[0054] Where N0, N0-1, N0-2, and N0-3 represent the N0th, N0-1st, N0-2nd, and N0-3rd iterations of the particle swarm, respectively.

[0055] The beneficial effects of this invention are as follows: This invention can reasonably optimize the surface electric field distribution of power equipment under the condition that the surface electric field of the double-ring equalizing ring meets the safety limit of corona initiation in high-altitude areas. The PSO algorithm used can effectively shorten the optimization design time of the equalizing ring and ensure the long-term safe and stable operation of power equipment in high-altitude areas. Attached Figure Description

[0056] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0057] Figure 1 This is a flowchart of the present invention;

[0058] Figure 2 This is a schematic diagram of the core structural parameters of the double-ring equalizing ring. Detailed Implementation

[0059] The present invention will be further described in detail below:

[0060] This invention provides an optimization method for a dual-ring voltage equalization ring at the high-voltage end of power equipment in high-altitude areas, comprising the following steps:

[0061] S1. Perform geometric modeling of the power equipment and the double-ring equalizing ring;

[0062] S2. The physical geometric model is transformed into a finite element method (FEM) model. Electrical boundary conditions are then applied to the FEM model. The combination of geometric parameters is represented by particles to obtain an initial particle swarm. Finally, the maximum electric field intensity E on the surface of the power equipment under the geometric parameter combination corresponding to the initial particle swarm is calculated. i-max1 The maximum electric field strength E along the surface of the equalizing ring i-max2 ;

[0063] S3. Based on the maximum electric field strength value E on the surface of the power equipment i-max1 The maximum electric field strength E along the surface of the equalizing ring i-max2 and the corrected corona induction electric field strength E 2H Calculate the fitness function value (Fitness);

[0064] S4. Find the individual extreme value P based on the fitness function value. best and the group extreme value G best The velocity and position of particles are updated based on individual and group extreme values ​​to obtain the updated particle swarm.

[0065] S5. Determine whether the population extremum is stable. If so, obtain the maximum electric field intensity along the surface of the double-ring equalizing ring corresponding to the stable population extremum and the combination of geometric parameters of the double-ring equalizing ring corresponding to the stable population extremum. If not, use the updated particle swarm as the initial particle swarm for the new round of iteration and repeat steps S2-S4 until the population extremum is stable.

[0066] S6. Verify whether the maximum electric field intensity along the surface of the double-ring equalizing ring corresponding to the stable population extremum in step S5 is less than the corona initiation electric field intensity of the double-ring equalizing ring after correction in step S3. If yes, determine the particle swarm corresponding to the stable population extremum, and combine the geometric parameters of the double-ring equalizing ring corresponding to the particle swarm corresponding to the stable population extremum into the optimal geometric parameters. If no, update the particle swarm corresponding to the stable population extremum in step S5, and use the updated particle swarm as the initial particle swarm, repeating steps S2-S5 until the optimal geometric parameters less than the corona initiation electric field intensity of the double-ring equalizing ring are determined. This method reduces the time and manpower costs in the parameter optimization process of the double-ring equalizing ring, and standardizes and improves the efficiency of the scientific design process for double-ring equalizing rings.

[0067] In this embodiment, in step S1, the physical geometry model of the power equipment and the double-ring equalizing ring is performed using the following method:

[0068] S11. Collect the structural geometric parameters, electrical parameters, and environmental parameters of the equipment's location. The electrical parameters of the power equipment include the maximum operating voltage and the maximum allowable electric field strength E1 at the maximum operating voltage. The environmental parameters include the altitude, temperature, air pressure, and humidity of the equipment's location.

[0069] S12. Perform full-scale modeling of the specific power equipment. The modeling software includes, but is not limited to: ANSYS, SolidWorks, ProE, Inventor, etc.

[0070] S13. Based on the structural geometric parameters of the power equipment collected in step S11, and combined with the local experience in the operation and installation of similar or identical equipment, determine the range of values ​​for the core geometric parameters of the double-ring equalizing ring: ring diameter, pipe diameter, and center distance between the two rings.

[0071] S14. Within the range of values ​​for the core geometric parameters of the double-ring equalizing ring—ring diameter, pipe diameter, and center distance between the two rings—determine Q sets of geometric parameter combinations as the initial particle swarm X = (X1, X2, ..., X...). Q (10≤Q≤30), define the ring diameter, pipe diameter and double ring center distance as design variables, then assign the initialized Q group of particle positions to the design variables, and perform parametric modeling based on these Q group of particle positions;

[0072] The particle position and velocity are initialized using the following method:

[0073] Initial particle swarm X = (X1, X2, ..., X Q Each particle in the vector represents a three-dimensional vector X. i =[X i1 ,Xi2 ,X i3 (i = 1, 2, 3, ..., Q), X i This represents the position of the i-th particle in three-dimensional space. The position and velocity of the particle are initialized using the following formula:

[0074]

[0075]

[0076] Where i is the particle's number in the population, m = 1, 2, 3, representing the three geometric parameters of the equalizing ring: ring diameter, pipe diameter, and center distance between the two rings, respectively, and rand(D m U m ) is in the interval [D m U m A function that generates uniformly distributed random numbers on [D]. m U represents the lower limit of the values ​​in the combination of geometric parameters. m The values ​​represent the upper limits of the geometric parameter combinations. D1 and U1 represent the lower and upper limits of the ring diameter, respectively; D2 and U2 represent the lower and upper limits of the pipe diameter, respectively; and D3 and U3 represent the lower and upper limits of the center distance between the two pipes, respectively. Using this method, Q random numbers can be generated quickly, avoiding data duplication and ensuring data independence and reliability.

[0077] In this embodiment, in step S2, the physical geometric model is converted into a finite element calculation model using the following method:

[0078] Artificial boundaries are set at a distance from the power equipment and the double-ring equalizing ring model to transform the open domain space near the power equipment and the double-ring equalizing ring into a finite domain. The power equipment, the double-ring equalizing ring and the finite domain are meshed and the physical geometric model is converted into a finite element calculation model.

[0079] The potential of the artificial boundary is set to 0, and the highest operating voltage collected in step S1 is applied to the high-voltage end of the conductor of the power equipment within the artificial boundary. The electric field and potential in the finite domain are solved using the finite element method to obtain the spatial distribution of the electric field and potential.

[0080] Within the solution domain, the electric field is solved:

[0081]

[0082]

[0083] Within the solution domain, the potential is solved:

[0084] N(D1-D2)=0

[0085] U1=U

[0086] U0 = 0

[0087] in, Here, ρ is the vector differential operator, ρ is the free charge density, E is the electric field intensity in the solution domain, and ε0 and ε r Let N be the vacuum permittivity and the relative permittivity of the medium, respectively; N be the normal vector perpendicular to the interface; D1 be the electric displacement perpendicular to the interface within the medium inside the artificial boundary; D2 be the electric displacement perpendicular to the interface within the medium outside the artificial boundary; U1 be the potential of the high-voltage conductor side; U be the specific potential value of the high-voltage conductor of the power equipment; and U0 be the finite boundary potential, which is the artificial boundary potential of 0. Based on the finite element calculation model, the initial particle swarm X = (X1, X2, ..., X...) is obtained. Q The maximum electric field strength E on the surface of the power equipment under the corresponding geometric parameter combination. i-max1 (i=1,2,3,…,Q) and the maximum electric field intensity E along the surface of the double-ring equalizing ring. i-max2 (i = 1, 2, 3, ..., Q).

[0088] In this embodiment, in step S3, the fitness function value is calculated using the following method:

[0089]

[0090] Where ω1 and ω2 are weight values, assigned by the decision-maker according to the weighting method, which includes, but is not limited to: subjective weighting methods (expert evaluation, analytic hierarchy process, etc.), and objective weighting methods (principal component analysis, factor analysis, entropy method, etc.), i represents the i-th particle, Fitness represents the fitness function value, and E i-max1 E represents the maximum electric field strength on the surface of electrical equipment. i-max2 E represents the maximum electric field strength along the surface of the double-ring equalizing ring. 1H This represents the result of altitude correction for the maximum permissible electric field strength E1 on the surface under the highest operating voltage. 2H The result of altitude correction for the corona initiation electric field strength E2 specified for the double-ring equalization ring;

[0091] The electric field strength is corrected for altitude using the following method:

[0092]

[0093] K a =K d ×K k

[0094]

[0095] Kh =K w

[0096] Among them, E kH E is the corrected electric field strength. k The electric field strength before correction is given. E1 represents the maximum permissible electric field strength on the surface under the highest operating voltage. E2 represents the corona initiation electric field strength specified by the dual-ring equalizing ring. E2 is determined according to the International Electrotechnical Commission standard IEC 60694. K a K is the altitude correction factor. d For air density correction factor, δ is relative air density, n is relative air density index, P is actual atmospheric pressure, t is actual air pressure temperature, P0 is atmospheric pressure under reference atmospheric pressure conditions, t0 is temperature under reference atmospheric pressure conditions, w is correction index, and K depends on the test voltage type.

[0097] In this embodiment, in step S4, the velocity and position of the particle swarm are updated using the following method:

[0098] Individual extreme value P best The extreme value P represents the position with the best calculated fitness value among the positions traversed by a particle. best Represented as:

[0099]

[0100] Population extreme value G best The population extreme value G represents the position where all particles find the optimal fitness value. best Represented as:

[0101]

[0102] The velocity and position of the particle swarm are updated based on individual and swarm extreme values, using the following formula:

[0103]

[0104]

[0105] in, Let represent the velocity of the i-th particle in the (S+1)-th iteration, c1 and c2 represent learning factors (non-negative constants), and r1 and r2 represent random numbers ranging from [0,1]. This represents the position of the i-th particle in the (S+1)-th iteration. The velocity and position of the particle swarm are updated using existing techniques, which will not be elaborated upon here. Using the above method, the optimal fitness value of the particle swarm can be quickly found, and further, the corresponding geometric parameter combination can be quickly found.

[0106] In this embodiment, in step S5, it is determined whether the population extreme value is stable. When the population extreme value simultaneously satisfies the following three conditions, it is determined that the population extreme value is stable. The maximum electric field intensity along the surface of the double-ring equalizing ring corresponding to the optimal fitness value and the combination of geometric parameters of the double-ring equalizing ring corresponding to the optimal fitness value are obtained. The conditions for determining the stability of the population extreme value are:

[0107]

[0108]

[0109]

[0110] Where N0, N0-1, N0-2, and N0-3 represent the N0th, N0-1st, N0-2th, and N0-3th iterations of the particle swarm, respectively, and the number of particles in each iteration is Q (10≤Q≤30).

[0111] When the group extremum does not meet the condition, for example, when iterating to the N0th time, However, the N0-1th and N0-2th times do not satisfy the condition. Then, the particle swarm updated after the N0th iteration should be used as the initial particle swarm for the N0+1th iteration. Steps S2-S4 are repeated until the population extremum simultaneously satisfies all three conditions. Using this method, a stable particle swarm with small errors can be obtained.

[0112] In this embodiment, in step S6, it is verified whether the maximum electric field intensity along the surface of the double-ring equalizing ring corresponding to the group extremum that meets the conditions in step S5 is less than the corona initiation electric field intensity E of the double-ring equalizing ring after correction in step S3. 2H If so, then the combination of geometric parameters of the double-ring equalizing ring corresponding to the particle swarm that satisfies the conditions is determined as the optimal geometric parameters.

[0113] If not, update the particle swarm corresponding to the population extremum that meets the conditions in step S5, and use the updated Q particles as the initial particles. Repeat steps S2-S5 until the maximum electric field intensity along the surface of the double-ring equalizing ring is determined that is less than the corrected halo electric field intensity of the double-ring equalizing ring. For example, when step S5 determines the particle swarm X after M iterations... M Corresponding group extreme value Satisfying the conditions in step S5, we obtain the particle swarm X. M The corresponding geometric parameter combination C of the double-ring equalizing ring M The maximum electric field intensity E along the surface of the double-ring equalizing ring M , when E M The electric field strength E of the double-ring equalizing ring is less than the corrected value. 2H At that time, particle swarm X M The corresponding geometric parameter combination C of the double-ring equalizing ringM For optimal geometric parameters; when E M The corona induction electric field strength E of the double-ring equalizing ring is greater than the corrected value. 2H At that time, the particle swarm X M Update the particle swarm X. M′ As the initial particle swarm X in the (M+1)th iteration M+1 For particle swarm X M+1 Repeat steps S2-S4 to obtain the population extremum. Determining the extreme value of a population Does the condition meet? If so, then the particle swarm X... M+1 The corresponding maximum electric field intensity E along the surface of the double-ring equalizing ring M+1 The corona induction electric field intensity E of the corrected double-ring equalizing ring 2H When E is compared, M+1 The electric field strength E of the double-ring equalizing ring is less than the corrected value. 2H At that time, particle swarm X M+1 The corresponding geometric parameter combination C of the double-ring equalizing ring M+1 For optimal geometric parameters, when E M+1 The corona induction electric field strength E of the double-ring equalizing ring is greater than the corrected value. 2H Then, repeat steps S2-S5 until the (M+a)th iteration to obtain the particle swarm X. M+a Corresponding volume extreme value While satisfying the condition in step S5, the particle swarm X M+a The corresponding maximum electric field intensity E along the surface of the double-ring equalizing ring M+a The electric field strength E of the double-ring equalizing ring is less than the corrected value. 2H Particle swarm X M+a The corresponding geometric parameters C of the double-ring equalizing ring M+a As the optimal geometric parameters, the above method ensures that the double-ring voltage equalization ring meets the corona initiation conditions. It also enables the rapid and scientific design and optimization of the parameter combination of the double-ring voltage equalization ring, reducing time and labor costs and guaranteeing the long-term safe and stable operation of power equipment in high-altitude areas.

[0114] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for optimizing the dual-ring voltage equalization ring at the high-voltage end of power equipment in high-altitude areas, characterized in that: Includes the following steps: S1. Perform geometric modeling of the power equipment and the double-ring equalizing ring; S2. The physical geometric model is transformed into a finite element method (FEM) model. Electrical boundary conditions are then applied to the FEM model. The combination of geometric parameters is represented by particles to obtain an initial particle swarm. Finally, the maximum electric field strength on the surface of the power equipment under the geometric parameter combination corresponding to the initial particle swarm is calculated. Maximum electric field strength along the surface of the equalizing ring ; S3. Based on the maximum electric field strength value on the surface of the power equipment. Maximum electric field strength along the surface of the equalizing ring and the corrected corona induction electric field strength Calculate the fitness function value ; S4. Find the individual extreme value based on the fitness function value. and group extreme values The velocity and position of particles are updated based on individual and group extreme values ​​to obtain the updated particle swarm. S5. Determine whether the population extremum is stable. If so, obtain the maximum electric field intensity along the surface of the double-ring equalizing ring corresponding to the stable population extremum and the combination of geometric parameters of the double-ring equalizing ring corresponding to the stable population extremum. If not, use the updated particle swarm as the initial particle swarm for the new round of iteration and repeat steps S2-S4 until the population extremum is stable. S6. Verify whether the maximum electric field intensity along the surface of the double-ring equalizing ring corresponding to the stable population extremum in step S5 is less than the corona initiation electric field intensity of the double-ring equalizing ring in step S3. If yes, determine the particle swarm corresponding to the stable population extremum and combine the geometric parameters of the double-ring equalizing ring corresponding to the particle swarm corresponding to the stable population extremum into the optimal geometric parameters. If no, update the particle swarm corresponding to the stable population extremum in step S5, use the updated particle swarm as the initial particle swarm, and repeat steps S2-S5 until the optimal geometric parameters less than the corona initiation electric field intensity of the double-ring equalizing ring are determined. In step S2, the maximum electric field strength value on the surface of the power equipment and the maximum electric field strength value along the surface of the equalizing ring are obtained by the following method: The potential of the artificial boundary is set to 0, and the highest operating voltage collected in step S1 is applied to the high-voltage end of the power equipment conductor within the artificial boundary. The electric field and potential within the finite domain are solved using the finite element method to obtain the spatial distribution of the electric field and potential. Within the solution domain, the electric field is solved: Within the solution domain, the potential is solved: in, For vector differential operators, Free charge density, To solve for the electric field strength within the domain, These are the vacuum permittivity and the relative permittivity of the medium, respectively. The normal vector is perpendicular to the interface. It represents the electric displacement perpendicular to the medium interface within the artificial boundary medium. The electric displacement perpendicular to the medium interface within the medium outside the artificial boundary. This is the potential on the high-voltage conductor side. This refers to the specific potential value of the high-voltage end conductor of the power equipment. The boundary potential is finite, and the artificial boundary potential is 0; based on the finite element calculation model, the initial particle swarm is obtained. Maximum electric field strength on the surface of power equipment under the corresponding combination of geometric parameters Maximum electric field strength along the surface of the double-ring equalizing ring ; In step S3, the fitness function is calculated using the following method. value: in, , These are weight values, assigned by the decision-maker according to the weighting method. Indicates the first One particle, This represents the fitness function value. This represents the maximum electric field strength value on the surface of electrical equipment. This represents the maximum electric field strength along the surface of the double-ring equalizing ring. Indicates the maximum permissible electric field strength of the surface under the highest operating voltage. The result after altitude correction The specified corona initiation electric field strength for a double-ring equalizing ring The result after altitude correction.

2. The optimization method for the double-ring voltage equalization ring at the high-voltage end of power equipment in high-altitude areas according to claim 1, characterized in that: In step S1, the electrical equipment and the double-ring equalizing ring are geometrically modeled using the following method: S11. Collect the structural geometric parameters, electrical parameters, and environmental parameters of the equipment's location; S12. Perform full-scale structural modeling of specific power equipment; S13. Based on the structural geometric parameters of the power equipment collected in step S11, and combined with the local experience in the operation and installation of similar or identical equipment, determine the range of values ​​for the core geometric parameters of the double-ring equalizing ring: ring diameter, pipe diameter, and center distance between the two rings. S14. Within the range of values ​​for the core geometric parameters of the double-ring equalizing ring—ring diameter, pipe diameter, and center distance between the two rings—determine Q sets of geometric parameter combinations as the initial particle swarm. The ring diameter, pipe diameter, and center distance between the two rings are defined as design variables. Then, the positions of the Q groups of particles after initialization are assigned to the design variables, and parametric modeling is performed based on these Q groups of particle positions.

3. The optimization method for the double-ring voltage equalization ring at the high-voltage end of power equipment in high-altitude areas according to claim 2, characterized in that: The particle positions are initialized using the following method: Initial Particle Swarm Each particle in the vector represents a three-dimensional vector X. i =[X i1 ,X i2 ,X i3 (i = 1, 2, 3, ..., Q), This represents the position of the i-th particle in three-dimensional space. The position and velocity of the particle are initialized using the following formula: in, This is the particle's number within the population. These represent the three geometric parameters of the equalizing ring: ring diameter, pipe diameter, and center distance between the two rings, respectively. This indicates the lower limit of the values ​​that can be taken in a combination of geometric parameters. This indicates the upper limit of the possible values ​​in a combination of geometric parameters.

4. The optimization method for the double-ring voltage equalization ring at the high-voltage end of power equipment in high-altitude areas according to claim 2, characterized in that: The electrical parameters of the power equipment include: the maximum operating voltage and the maximum permissible electric field strength E1 on the surface under the maximum operating voltage. The environmental parameters include: the altitude, temperature, air pressure and humidity of the equipment's location.

5. The optimization method for the double-ring voltage equalization ring at the high-voltage end of power equipment in high-altitude areas according to claim 1, characterized in that: In step S2, the physical geometric model is transformed into a finite element calculation model using the following method: Artificial boundaries are set at a distance from the power equipment and the double-ring equalizing ring model to transform the open domain space near the power equipment and the double-ring equalizing ring into a finite domain. The power equipment, the double-ring equalizing ring and the finite domain are meshed, and the physical geometric model is converted into a finite element calculation model.

6. The optimization method for the double-ring voltage equalization ring at the high-voltage end of power equipment in high-altitude areas according to claim 1, characterized in that: The electric field strength is corrected for altitude using the following method: in, The corrected electric field strength, The electric field strength before correction. This is the altitude correction factor. For air density correction factor, Relative air density, The relative air density index. This is the actual atmospheric pressure. This refers to the actual air pressure and temperature. Atmospheric pressure under reference atmospheric pressure conditions, Temperature under reference atmospheric pressure conditions, To correct the index, It depends on the type of test voltage.

7. The optimization method for the double-ring voltage equalization ring at the high-voltage end of power equipment in high-altitude areas according to claim 1, characterized in that: In step S4, the velocity and position of the particle swarm are updated using the following method: Individual extreme values This represents the position with the optimal calculated fitness value among the positions experienced by a particle; it is the population extreme value. This indicates that all particles have found the optimal fitness value. The velocity and position of the particle swarm are updated based on the individual and swarm extreme values. The update formula is: in, This represents the velocity of the i-th particle in the (S+1)-th iteration. , The learning factor is a non-negative constant. , Represents a random number. This represents the position of the i-th particle in the (S+1)-th iteration.

8. The optimization method for the double-ring voltage equalization ring at the high-voltage end of power equipment in high-altitude areas according to claim 1, characterized in that: In step S5, the population is considered stable when the population extreme value simultaneously satisfies the following three conditions: in, , , , These represent the particle swarm iterations. , , , Second-rate.

Images