Method and related apparatus for determining Thomson's second coefficient in the criterion for electrode photoionization and corona formation

Abstract

This invention discloses a method and related apparatus for determining the Townsend second coefficient in an electrode photoionization corona criterion, belonging to the field of electrode technology. The method determines the ionization region boundary of a conductor during corona initiation using corona initiation voltage, environmental parameters, and the nominal electric field analytical formula. Based on the obtained ionization region boundary, Morrow's ionization coefficient and adhesion coefficient formulas are used to substitute the nominal electric field analytical formula into the photoionization corona criterion, yielding an integral expression for the criterion. The integral interval of the integral expression is discretized, and an initial value is assigned to the Townsend second coefficient. This value is then substituted into the photoionization corona criterion for discretized integral calculation, ultimately obtaining the Townsend second coefficient. This invention can be applied to all AC / DC conductors requiring the use of the photoionization corona criterion, and can determine the Townsend second coefficient of conductor corona initiation under varying conductor geometry, ground elevation, humidity, air pressure, and temperature conditions.

Description

Technical Field

[0001] This invention belongs to the field of electrode technology and relates to a method and related apparatus for determining the Townsend second coefficient in the criterion of electrode photoionization halo. Background Technology

[0002] The photoionization corona criterion, a key indicator for evaluating the performance of electrical equipment, has extremely wide applications, covering various conductors and other electrical components from DC to AC systems. This criterion plays a crucial role not only in the design and maintenance of large-scale power facilities such as high-voltage transmission lines, transformers, and instrument transformers, but also extends to laboratory research, the development of power electronic equipment, and new energy technologies. Among these, the Townsend second coefficient, a core parameter in the photoionization corona criterion, has a profound impact on the accuracy and reliability of the criterion. It directly relates to the generation and distribution of charge during ionization, thus affecting the insulation performance and operational stability of electrical equipment.

[0003] Because Townsend's second coefficient is difficult to calculate precisely through purely theoretical derivation, its value often depends on the accumulation and analysis of experimental data. Further complicating matters, the physical mechanisms of positive and negative corona discharges during photoionization differ significantly, leading to different physical meanings and numerical representations of the Townsend's second coefficient in positive and negative corona scenarios. For example, Naidis attempted to deduce the Townsend's second coefficient for positive corona discharges using experimental data from Zheleznyak et al., but the results deviated significantly from actual observations, reflecting the complexity and uncertainty of this coefficient in practical applications. The situation is even more complex for negative corona discharges. Since the photoionization process of negative corona discharges is closely related to the properties of the conductor surface material, and different materials exhibit significantly different electron emission characteristics, this affects the specific value of the Townsend's second coefficient. Therefore, it is difficult to provide a universally applicable and definitive value for the Townsend's second coefficient for negative corona discharges, which undoubtedly increases the difficulty of accurately evaluating the performance of electrical equipment.

[0004] Scholars now typically use the default value for Thomson's second coefficient, commonly 3 × 10⁻⁶. -3 The positive and negative corona charges are often taken to be the same. Although this simplifies the calculation process, it ignores the difference between the positive and negative corona charges and the influence of the conductor surface material on the coefficient, which leads to certain errors in the calculation results. Summary of the Invention

[0005] The purpose of this invention is to provide a method and related apparatus for determining the Townsend second coefficient in the electrode photoionization halo criterion, so as to solve the technical problem that the value of the Townsend second coefficient is inaccurate in the prior art, which affects the accuracy of the photoionization halo criterion.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] In a first aspect, the present invention provides a method for determining the Townsend second coefficient in an electrode photoionization halo criterion, comprising the following steps:

[0008] The boundary of the ionization zone at the time of corona initiation of the conductor is determined by the corona initiation voltage, environmental parameters, and the analytical formula of the nominal electric field.

[0009] Based on the obtained boundary c of the ionization zone when the conductor corona occurs, Morrow's formulas for the ionization coefficient and adhesion coefficient are used to substitute the analytical formula of the nominal electric field into the photoionization corona criterion, and the integral expression of the photoionization corona criterion is obtained.

[0010] The integral interval in the integral expression of the photoionization halo criterion is discretized, and the Townsend second coefficient is assigned an initial value. The discretized integral is then substituted into the photoionization halo criterion to obtain the Townsend second coefficient.

[0011] Furthermore, the step of determining the ionization region boundary of the conductor at the time of corona initiation using the corona initiation voltage, environmental parameters, and the nominal electric field analytical formula specifically includes:

[0012] The boundary c of the ionization region at the corona initiation point of the conductor is calculated using the corona initiation voltage, relative air density, and the analytical formula for the nominal electric field. The specific calculation formula is as follows:

[0013]

[0014]

[0015] In the formula, h is the height of the conductor center above the ground; a is the conductor radius; U is the voltage; and b is a constant. r is the distance from the point of observation to the center of the conductor; δ is the relative air density; E is the nominal electric field.

[0016] For a positive corona, the boundary c of the ionization region is used directly;

[0017] For a negative corona, the ionization boundary c is transformed into the effective ionization boundary m of the negative corona.

[0018] Furthermore, the specific calculation formula for the step of transforming the ionization boundary c into the effective ionization boundary m of the negative corona is as follows:

[0019] α'(r k )+α(r k )[α(r k )-η(r k )]=0 (4)

[0020]

[0021] In the formula, α is the ionization coefficient; η is the electron adsorption coefficient; and a is the radius of the conductor.

[0022] Furthermore, the formulas for the ionization coefficient and adhesion coefficient of Morrow are as follows:

[0023]

[0024] In the formula, α is the ionization coefficient; η is the electron adsorption coefficient; N is the gas molecule number density; and E is the electric field strength.

[0025] Furthermore, the expression for the photoionization halo criterion specifically includes:

[0026] The criterion for photoionization and corona formation of a positive conductor is:

[0027]

[0028] In the formula, A + The photoionization corona criterion for a positive conductor; γ p+ denoted as Townsend's second coefficient for positive corona discharge; μ is the photon absorption coefficient; a is the radius of the conductor; and r is the distance from the observation point to the center of the conductor.

[0029] The criterion for photoionization and corona formation of a negative conductor is:

[0030]

[0031] In the formula, A - The photoionization corona criterion for a negative conductor; γ p- Townsend's second coefficient for negative corona discharge.

[0032] Furthermore, the step of discretizing the integral interval in the integral expression of the photoionization halo criterion, assigning initial values ​​to the Townsend second coefficient, and substituting them into the photoionization halo criterion for discretized integral calculation to finally obtain the Townsend second coefficient specifically includes:

[0033] Discretize the integral interval in the integral expression of the photoionization halo criterion, and assign Townsend's second coefficient γ. p Initialize to γ p0 and set γ p min <γ p <γ p max ;

[0034] Judge A + / - If the value of γ does not meet the set conditions, then change the second coefficient γ of Townsend. p The value until A + / - If the magnitude of the coefficient satisfies the preset condition, output the Townsend second coefficient γ. p .

[0035] Furthermore, the judgment A+ / - If the value of γ does not meet the set conditions, then change the second coefficient γ of Townsend. p The value until A + / - If the magnitude of the coefficient satisfies the preset condition, output the Townsend second coefficient γ. p The steps specifically include:

[0036] Judge A + / - Does it satisfy | A + / - -1|<ε0, where ε0 is the preset precision;

[0037] If |A is not satisfied + / - -1|<ε0, then let γ pmin =γ p , using γ p =(γ pmin +γ pmax ) / 2 Re-evaluate A + / - Whether the size meets the set conditions, iterate multiple times until A is reached. + / - If the preset criteria are met, output the result;

[0038] If |A + / - -1|<ε0, then let γ pmax =γ p , using γ p =(γ pmin +γ pmax ) / 2 Re-evaluate A + / - Whether the size meets the set conditions, iterate multiple times until A is reached. + / - If the preset criteria are met, output the result.

[0039] Secondly, the present invention provides a system for determining the Townsend second coefficient in an electrode photoionization halo criterion, comprising:

[0040] The ionization zone boundary calculation module is used to determine the ionization zone boundary of a conductor when it corona begins to corona using corona initiation voltage, environmental parameters, and the analytical formula of the nominal electric field.

[0041] The integral expression determination module is used to determine the integral expression of the photoionization corona criterion by substituting the nominal electric field analytical formula into the photoionization corona criterion based on the obtained ionization zone boundary c when the conductor corona occurs, using Morrow's formulas for ionization coefficient and adhesion coefficient.

[0042] The assignment and calculation module is used to discretize the integral interval in the integral expression of the photoionization halo criterion, assign initial values ​​to the Townsend second coefficient, substitute them into the photoionization halo criterion for discretized integral calculation, and finally obtain the Townsend second coefficient.

[0043] Thirdly, the present invention provides a computer device including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method described above.

[0044] Fourthly, the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the method described above.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] This invention discloses a method and related apparatus for determining the Townsend second coefficient in an electrode photoionization corona criterion. First, the corona initiation voltage, relative air density, and nominal electric field analytical formula are obtained experimentally to determine the ionization zone boundary at the time of corona initiation in the conductor. Then, Morrow's ionization coefficient and adhesion coefficient formulas are used, and the nominal electric field analytical expression is substituted into the photoionization corona criterion. Finally, the integral interval in the criterion is discretized, an initial value is assigned to the Townsend second coefficient, and it is substituted into the photoionization criterion for discretized integral calculation. The criterion is then checked to determine if the condition is met. If not, the Townsend second coefficient is changed until the condition is met, at which point the Townsend second coefficient is obtained. This invention can be applied to all AC and DC conductors that require the use of a photoionization corona criterion, and can determine the Townsend second coefficient of conductor corona initiation under varying conductor geometry, height above ground, humidity, air pressure, and temperature. For positive corona, the Townsend second coefficient determined by this method can be well used for corona prediction of conductor types that have not been experimentally tested. For negative corona, the integration region in the criterion has been improved, avoiding truncation errors and making it well-suited for corona initiation prediction of conductors made of the same material. It can also distinguish between the positive and negative Thomson second coefficients under the same external conditions. Attached Figure Description

[0047] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a flowchart of the method of the present invention;

[0049] Figure 2 This is a schematic diagram of the system of the present invention;

[0050] Figure 3 This is a schematic diagram of the wires in an embodiment of the present invention;

[0051] Figure 4 This is a flowchart illustrating the determination of the second coefficient of Thomson in the electrode photoionization halo criterion of this invention.

[0052] Figure 5 This is a schematic diagram of the computer device structure of the present invention. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0054] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0055] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0056] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0057] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0058] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0059] The present invention will now be described in further detail with reference to the accompanying drawings:

[0060] See Figure 1 This invention discloses a method for determining the Townsend second coefficient in the electrode photoionization halo criterion, comprising the following steps:

[0061] S1, the boundary of the ionization zone when the conductor corona is initiated is determined by the corona initiation voltage, environmental parameters and the nominal electric field analytical formula;

[0062] The corona initiation voltage was obtained experimentally, and the relative air density and nominal electric field were monitored. The boundary c of the ionization region at the corona initiation point of the conductor was calculated using the analytical formula. The specific calculation formula is as follows:

[0063]

[0064] In the formula, h is the height of the conductor center above the ground; a is the conductor radius; U is the voltage; and b is a constant. r is the distance from the point of observation to the center of the conductor; δ is the relative air density; E is the nominal electric field.

[0065] For a positive corona, the boundary c of the ionization region is used directly;

[0066] For a negative corona, the ionization boundary c is transformed into the effective ionization boundary m of the negative corona. The specific calculation formula is as follows:

[0067] α'(r k )+α(r k )[α(r k )-η(r k )]=0 (4)

[0068]

[0069] In the formula, α is the ionization coefficient; η is the electron adsorption coefficient; and a is the radius of the conductor.

[0070] S2, Based on the obtained boundary c of the ionization zone when the conductor corona occurs, Morrow's formulas for ionization coefficient and adhesion coefficient are used to substitute the nominal electric field analytical formula into the photoionization corona criterion to obtain the integral expression of the photoionization corona criterion.

[0071] The formulas for Morrow's ionization coefficient and adhesion coefficient are as follows:

[0072]

[0073] In the formula, α is the ionization coefficient; η is the electron adsorption coefficient; N is the gas molecule number density; and E is the electric field strength.

[0074] The expression for the photoionization halo criterion specifically includes:

[0075] The criterion for photoionization and corona formation of a positive conductor is:

[0076]

[0077] In the formula, A + The photoionization corona criterion for a positive conductor; γ p+ denoted as Townsend's second coefficient for positive corona discharge; μ is the photon absorption coefficient; a is the radius of the conductor; and r is the distance from the observation point to the center of the conductor.

[0078] The criterion for photoionization and corona formation of a negative conductor is:

[0079]

[0080] In the formula, A - The photoionization corona criterion for a negative conductor; γ p- Townsend's second coefficient for negative corona discharge.

[0081] S3 discretizes the integral interval in the integral expression of the photoionization halo criterion, assigns an initial value to the Townsend second coefficient, substitutes it into the photoionization halo criterion for discretized integral calculation, and finally obtains the Townsend second coefficient.

[0082] Judge A + / - Does it satisfy | A + / - -1|<ε0, where ε0 is the preset precision;

[0083] If |A is not satisfied + / - -1|<ε0, then let γ pmin =γ p , using γ p =(γ) pmin +γ pmax ) / 2 Re-evaluate A + / - Whether the size meets the set conditions, iterate multiple times until A is reached. + / - If the preset criteria are met, output the result;

[0084] If |A + / - -1|<ε0, then let γ pmax =γ p , using γ p =(γ) pmin +γ pmax ) / 2 Re-evaluate A + / - Whether the size meets the set conditions, iterate multiple times until A is reached. + / - If the preset criteria are met, output the result.

[0085] See Figure 2 This invention discloses a system for determining the second coefficient of Townsend in the criterion of electrode photoionization halo, including an ionization region boundary calculation module, an integral expression determination module, and an assignment calculation module.

[0086] It should be noted that the ionization zone boundary calculation module is used to determine the ionization zone boundary of the conductor at the time of corona initiation using the corona initiation voltage, environmental parameters, and the nominal electric field analytical formula. For positive corona, the ionization zone boundary c is used directly; for negative corona, the ionization boundary c is transformed into the effective ionization boundary m of the negative corona. The specific calculation formula is as follows:

[0087]

[0088] The integral expression determination module is used to determine the integral expression of the photoionization corona criterion by substituting the nominal electric field analytical formula into the photoionization corona criterion based on the obtained ionization zone boundary c when the conductor corona occurs, using Morrow's formulas for ionization coefficient and adhesion coefficient.

[0089] The assignment and calculation module is used to discretize the integration interval in the integral expression of the photoionization halo criterion, assign initial values ​​to the Townsend second coefficient, and substitute them into the photoionization halo criterion for discretized integration calculation, ultimately obtaining the Townsend second coefficient. Specifically, the judgment process is as follows: Judge A + / - Does it satisfy | A + / - -1|<ε0, where ε0 is the preset precision;

[0090] If |A is not satisfied + / - -1|<ε0, then let γ pmin =γ p , using γ p =(γ) pmin +γ pmax ) / 2 Re-evaluate A + / - Whether the size meets the set conditions, iterate multiple times until A is reached. + / - If the preset criteria are met, output the result;

[0091] If |A + / - -1|<ε0, then let γ pmax =γp , using γ p =(γ) pmin +γ pmax ) / 2 Re-evaluate A + / - Whether the size meets the set conditions, iterate multiple times until A is reached. + / - If the preset criteria are met, output the result.

[0092] Example:

[0093] This embodiment discloses a method for determining the Townsend second coefficient in the electrode photoionization halo criterion, as follows:

[0094] See Figure 3 For the area directly below the center of the conductor, the electric field strength has only the y-component, and the electric field strength is greatest on the surface of the conductor, where the halo effect occurs first. Taking the direction of the electric field strength as the positive y-axis, for the nominal electric field E directly below the center of the negative conductor, we have analytical formula (1). In formula (1), h is the height of the conductor center above the ground, a is the radius of the conductor, and U is the applied voltage. r is the distance from the observation point to the center of the conductor. Along the negative y-axis from the center of the conductor, we can obtain equation (2). Here, c is the boundary of the ionization region, that is, the electron adsorption coefficient is equal to the ionization coefficient. E0 is the nominal electric field strength at c under standard atmospheric pressure at 20 degrees Celsius, which is a definite quantity. δ is the relative air density. The relationship between the corona initiation field strength and the ionization boundary is determined by equation (3). In this way, the ionization boundary c can be obtained from the corona initiation voltage obtained experimentally.

[0095] The photoionization corona initiation criteria for positive and negative conductors are given by equations (8) and (9), respectively. For positive corona, c can be directly used. For negative corona, the ionization boundary c is transformed into the effective ionization boundary m of the negative corona from equations (4) and (5). Using Morrow's formulas for the ionization coefficient and electron adsorption coefficient, namely equations (6) and (7), and substituting equation (1), the integral expression of the entire criterion can be obtained. In this way, the Townsend second coefficient can be calculated using a simple procedure.

[0096] The width of the entire ionization region from the conductor surface to the ionization boundary is discretized, and the number of discretized parts is taken as C1. Calculations and verifications show that the calculation results are accurate when C1 is generally greater than or equal to 5000. The program flow is as follows: Figure 4 As shown, the second coefficient γ of Townsend is given. p Initialize to γ p0 From γ p0 Start calculating (γ) p Generally γ pmin -γ pmax Between. γ pmin With γ pmax You can modify them as needed, as long as you ensure that the criteria are substituted into the calculations to make the criterion less than 1 and greater than 1. Generally, they can be set to 10 respectively. -4With 10 -1 ), determine whether the criterion meets the condition (generally, the absolute value of the difference between the calculation result of equations (8) and (9) and 1 is less than ε0, where ε0 is the precision and can be changed as needed), if not, change γ p This continues until the criteria are met.

[0097] It should be noted that the method of this invention can be applied to all electrode structures with an analytical expression for nominal electric field strength, including: wire-plate electrodes (in this embodiment), coaxial cylinders, parallel-plate electrodes, etc. This method can be used for all of them.

[0098] The purpose of this invention is to provide a method for determining the Townsend second coefficient using the corona initiation voltage of a wire-plate electrode obtained experimentally. This method utilizes the photoionization corona initiation criterion, where the area factor of the wire-plate electrode has an analytical formula. It employs the analytical formula for the nominal electric field of the wire-plate electrode, as well as Morrow's formulas for the ionization coefficient and electron adsorption coefficient. Morrow's formula has been verified to agree well with experimental results. Therefore, given the analytical formula, the Townsend second coefficient can be obtained using a simple procedure. This invention can be applied to all AC / DC conductors requiring the use of the photoionization corona initiation criterion, and can determine the Townsend second coefficient for corona initiation under varying conductor geometry, height above ground, humidity, air pressure, and temperature. For positive corona, the Townsend second coefficient determined by this method can be well used for corona initiation prediction of conductor types for which experiments have not been conducted. For negative corona, the integration region in the criterion is improved, avoiding truncation errors, and it can be well used for corona initiation prediction of conductors made of the same material. Obtaining the difference between positive and negative Thomson's second coefficient under the same external conditions helps to understand the mechanism of gas discharge more deeply and has practical value in discharge control during the design, manufacturing and operation of electrical equipment.

[0099] In one embodiment of the present invention, a computer device is provided, comprising a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in the computer storage medium to achieve a corresponding method flow or corresponding function. The processor described in this embodiment of the present invention can be used in the operation of the Thomson second coefficient determination method in the electrode photoionization corona criterion.

[0100] This invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and extended storage media supported by the computer device. The computer-readable storage medium provides storage space that stores the terminal's operating system. Furthermore, this storage space also stores one or more instructions suitable for loading and execution by a processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be high-speed RAM or non-volatile memory, such as at least one disk storage device. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the Townsend second coefficient determination method in the electrode photoionization corona criterion in the above embodiments.

[0101] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0102] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0103] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0104] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0105] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for determining the Townsend second coefficient in an electrode photoionization halo criterion, characterized in that, Includes the following steps: The ionization region boundary at the time of corona initiation in a conductor is determined by using the corona initiation voltage, environmental parameters, and the analytical formula of the nominal electric field; for positive corona, the ionization region boundary is directly utilized. ; For negative corona, the boundary will be ionized. The effective ionization boundary is transformed into a negative corona. ; Based on the boundary of the ionization zone when the conductor corona occurs, Morrow's formulas for ionization coefficient and adhesion coefficient are used to substitute the analytical formula of the nominal electric field into the photoionization corona criterion, resulting in the integral expression of the photoionization corona criterion. The integral expression for the photoionization halo criterion specifically includes: The criterion for photoionization and corona formation of a positive conductor is: （8） In the formula, Criteria for photoionization corona formation in a positive conductor; Townsend's second coefficient for positive corona discharge; The photon absorption coefficient; The radius of the conductor; It is the distance from the observation point to the center of the guide wire; The criterion for photoionization and corona formation of a negative conductor is: （9） In the formula, Criteria for photoionization corona formation in negative conductors; Townsend's second coefficient for negative corona discharge; The integral interval in the integral expression of the photoionization halo criterion is discretized, and the Townsend second coefficient is assigned an initial value. The discretized integral is then substituted into the photoionization halo criterion to obtain the Townsend second coefficient.

2. The method for determining the Townsend second coefficient in the electrode photoionization halo criterion according to claim 1, characterized in that, The step of determining the ionization region boundary of a conductor at the time of corona initiation using corona initiation voltage, environmental parameters, and the nominal electric field analytical formula specifically includes: The boundary of the ionization region at the time of corona initiation of the conductor was calculated using analytical formulas based on corona initiation voltage, relative air density, and nominal electric field. The specific calculation formula is as follows: （1） （2） （3） In the formula, The height of the conductor center above the ground; The radius of the conductor; Voltage; b It is a constant. ; It is the distance from the observation point to the center of the guide wire; δ Relative air density; The nominal electric field; It is the nominal electric field strength at 20 degrees Celsius and standard atmospheric pressure.

3. The method for determining the Townsend second coefficient in the electrode photoionization halo criterion according to claim 2, characterized in that, The ionization boundary The effective ionization boundary is transformed into a negative corona. The steps and specific calculation formula are as follows: （4） （5） In the formula, The ionization coefficient; The electron adsorption coefficient; Let be the radius of the conductor.

4. The method for determining the Townsend second coefficient in the electrode photoionization halo criterion according to claim 1, characterized in that, The formulas for Morrow's ionization coefficient and adhesion coefficient are as follows: （6） （7） In the formula, The ionization coefficient; The electron adsorption coefficient; N The gas molecule number density; This is the nominal electric field.

5. The method for determining the Townsend second coefficient in the electrode photoionization halo criterion according to claim 1, characterized in that, The steps of discretizing the integral interval in the integral expression of the photoionization halo criterion, assigning initial values ​​to the Townsend second coefficient, substituting them into the photoionization halo criterion for discretized integral calculation, and finally obtaining the Townsend second coefficient, specifically include: Discretize the integral interval in the integral expression of the photoionization halo criterion, and assign Townsend's second coefficient. Initialize to and set ; judge If the value of the coefficient does not meet the set conditions, then change the second coefficient of the Thompson coefficient. The value, until If the value meets the preset condition, output the Thomson second coefficient. .

6. The method for determining the Townsend second coefficient in the electrode photoionization halo criterion according to claim 5, characterized in that, The judgment If the value of the coefficient does not meet the set conditions, then change the second coefficient of the Thompson coefficient. The value, until If the value meets the preset condition, output the Thomson second coefficient. The steps specifically include: judge Does it meet the requirements? -1|< , Preset precision; If not satisfied | -1|< Then let ,use Reassess Whether the size meets the set conditions, iterate multiple times until... If the preset criteria are met, output the result; If | -1|< Then let ,use Reassess Whether the size meets the set conditions, iterate multiple times until... If the preset criteria are met, output the result.

7. A system for determining the Townsend second coefficient in an electrode photoionization halo criterion, characterized in that, include: The ionization zone boundary calculation module is used to determine the ionization zone boundary of a conductor when it corona begins to corona using corona initiation voltage, environmental parameters, and the analytical formula of the nominal electric field. For positive corona, the boundary of the ionization region is used directly. ; For negative corona, the boundary will be ionized. The effective ionization boundary is transformed into a negative corona. ; The integral expression determination module is used to determine the ionization region boundary based on the obtained corona initiation of the conductor. By using Morrow's formulas for ionization coefficient and adhesion coefficient, and substituting the analytical formula for the nominal electric field into the photoionization corona criterion, we obtain the integral expression for the photoionization corona criterion. The integral expression for the photoionization halo criterion specifically includes: The criterion for photoionization and corona formation of a positive conductor is: （8） In the formula, Criteria for photoionization corona formation in a positive conductor; Townsend's second coefficient for positive corona discharge; The photon absorption coefficient; The radius of the conductor; It is the distance from the observation point to the center of the guide wire; The criterion for photoionization and corona formation of a negative conductor is: （9） In the formula, Criteria for photoionization corona formation in negative conductors; Townsend's second coefficient for negative corona discharge; The assignment and calculation module is used to discretize the integral interval in the integral expression of the photoionization halo criterion, assign initial values ​​to the Townsend second coefficient, substitute them into the photoionization halo criterion for discretized integral calculation, and finally obtain the Townsend second coefficient.

8. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1-6.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1-6.

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