Method, system and device for calculating electric field around ADSS optical cable and medium

Abstract

The invention relates to a method, a system and equipment for calculating an electric field around an ADSS optical cable, and a medium. The model can effectively calculate the electric field distribution around the optical cable by accurately modeling the geometrical shape and stress response of the power transmission line and combining the relationship between the charge density and the electric field. The electric field is solved through a finite element analysis method, a non-uniform division strategy is adopted, the calculation precision is guaranteed, and meanwhile the calculation cost is reduced. According to the equivalent charge method, the calculation process is simplified through virtual charge distribution, and high precision is maintained. The model solves the problems of complex electric field calculation and insufficient precision in the prior art, is widely applicable to electric field analysis and optical cable design of a power system, and provides effective support for safe operation of an ADSS optical cable.

Description

Technical Field

[0001] The present invention belongs to the field of space electric field calculation, and in particular to a method, system, device and medium for calculating the electric field around an ADSS optical cable. Background Art

[0002] With the continuous development of power systems and the gradual increase in voltage levels, ADSS (All-Dielectric Self-Supporting) optical cables, as a new type of communication equipment, have been widely used in high-voltage transmission lines. Their key features include the absence of metal materials, excellent electrical insulation properties, and resistance to electromagnetic interference, making them a key component of power communication and transmission systems. ADSS optical cables are also advantageous in their lightness, ease of installation, and strong corrosion resistance, making them particularly suitable for use in complex and harsh environments.

[0003] However, with the gradual increase in grid transmission voltage and the increasing complexity of the line environment, the electrical safety issues faced by ADSS optical cables during operation have become increasingly prominent. In particular, the impact of the electric field distribution around the optical cable under high electric field intensities has gradually become a research focus. The electric field distribution not only affects the long-term stability of the optical cable but can also cause electrical degradation of the cable's outer sheath, further shortening its service life. Furthermore, uneven electric field distribution can cause localized current leakage, increase cable temperature, and even trigger arc discharge, seriously threatening the mechanical safety of the cable.

[0004] Existing research primarily focuses on the selection of optical cable materials, their mechanical strength, and their environmental resistance. However, research on the precise calculation of the electric field around ADSS optical cables and its impact on cable performance remains limited. While some studies have employed finite element analysis (FEM) or other numerical methods to simulate the electric field, these methods are typically computationally intensive, require high computational resources, and are inefficient when dealing with complex geometries. Existing electric field calculation methods often struggle to balance computational accuracy and resource consumption, particularly when considering variations in the electric field under varying operating conditions in actual installation environments.

[0005] Currently, research on the electric field distribution of ADSS optical cables lacks an efficient and accurate calculation model that can effectively cope with electric field variations at different voltage levels and in complex environmental conditions. Therefore, developing a highly efficient calculation method that can accurately assess the electric field distribution around ADSS optical cables has become a pressing technical challenge.

[0006] In summary, the technical solution of the present invention has important theoretical significance and application prospects, can effectively fill the gaps in current research, promote the development of ADSS optical cable electric field calculation technology, and provide an innovative solution for related fields. Summary of the Invention

[0007] The present invention aims to provide a method, system, device, and medium for calculating the electric field around an ADSS optical cable, addressing existing issues such as low accuracy, high computational complexity, and difficulty effectively handling complex geometric structures. Conventional electric field calculation methods often suffer from high computational resource consumption, low accuracy, and insufficient adaptability to complex environments when used with optical cables in high-voltage transmission lines. To address this, the present invention employs a technical solution combining the equivalent charge method with finite element analysis, significantly improving computational efficiency while ensuring computational accuracy.

[0008] To achieve the above objectives, the present invention adopts the following technical solutions.

[0009] A method for calculating the electric field around an ADSS optical cable, characterized by the following specific steps:

[0010] S1: Transmission Line Structure Modeling

[0011] Model the geometry of transmission lines and construct equations to describe their shapes;

[0012] By introducing the elastic mechanics model, the lateral displacement and vertical strain equations of the transmission line are constructed, and the strain distribution of the transmission line and the mechanical response equations of the transmission line in the lateral and longitudinal directions are obtained;

[0013] S2: Calculate the charge distribution of transmission lines and construct an equivalent charge model

[0014] Use the finite element method to discretize each section of the transmission line into a series of small units, discretize the charge distribution of the transmission line into equivalent point charges, calculate the equivalent point charge density, construct an equivalent charge model, and calculate the equivalent charge Q for each section of the transmission line length Δl. eq :

[0015] S3: Using the equivalent charge model, calculate the electric field generated by each equivalent point charge at a certain point P(x,y,z) using Coulomb's law;

[0016] S4: Finite element analysis to solve the electric field

[0017] The electric field solution area is discretized into multiple small units, the electric potential expression in each unit is constructed, and the distribution of electric potential in each unit is calculated by the inner product;

[0018] Assemble the stiffness matrix K and load vector F of each unit, and obtain the stiffness matrix K of the entire system by combining the stiffness matrix and load vector of each unit according to their position total and the load vector F total ;

[0019] By solving the algebraic equation K total Φ=Ftotal , calculate the electric potential distribution Φ of the entire calculation area and obtain the electric field intensity;

[0020] S5: The calculated electric field intensity is mapped to the three-dimensional space around the transmission line, and the electric field distribution is mapped around the optical cable according to the position and geometry of the optical cable.

[0021] Specifically, the calculated distribution of electric field intensity at the nodes of the finite element mesh is spatially interpolated using an interpolation function, resulting in the electric field distribution in the entire three-dimensional space around the transmission line. This process ensures that the variations in electric field intensity at different locations (including the space around the transmission line and the area near the optical cable) can be accurately represented, providing basic data for subsequent safety assessment and design.

[0022] This method first calculates the electric field distribution around the transmission line and then maps this electric field distribution around the cable based on the cable's position and geometry. Because ADSS cables are typically suspended over high-voltage transmission lines, the electric field they experience is determined by the electric field of the transmission line. This method accurately infers the electric field distribution around the cable, allowing for the assessment of its electrical performance and safety.

[0023] Furthermore, in S1, simulating the geometry of the transmission line and constructing equations to describe its shape means:

[0024] The transmission lines at both ends of the tower will form a catenary shape after being subjected to force. Assuming that the transmission line deforms in a plane, its shape can be described by the following equation:

[0025]

[0026] Where y(x) represents the height of the transmission line at position x, a is a constant calculated based on the weight of the transmission line and other loads, and cosh is the hyperbolic cosine function.

[0027] Furthermore, in S1, the lateral displacement of the transmission line is constructed as follows:

[0028] An elastic mechanics model is introduced to accurately describe the response of the transmission line. The cross section of the transmission line is assumed to be circular. When subjected to wind pressure and ice loads, the deformation of the transmission line is affected by the following factors:

[0029] Gravity effect: Assuming that the mass of each transmission line is m and the length is l, the bending moment caused by the gravity of the transmission line is:

[0030] M(x)=m·g·x (2)

[0031] Where g is the acceleration of gravity, x is the horizontal position of the transmission line, and M(x) is the bending moment;

[0032] Wind pressure load: The impact of wind pressure load on transmission lines can be expressed by the following formula:

[0033] F wind (x) = C d ·ρ·A wind ·v 2 (x) (3)

[0034] Among them, C d is the drag coefficient, ρ is the air density, A wind is the frontal area of ​​the transmission line, v(x) is the wind speed, F wind (x) is the wind pressure load;

[0035] Ice load: Considering that snow or ice may accumulate on the surface of the transmission line, the surface load of the transmission line can be expressed as:

[0036] F ice (x)=σ ice ·A ice (4)

[0037] Among them, σ ice is the density of ice, A ice is the ice area on the transmission line surface, F ice (x) is the surface load of the transmission line;

[0038] Taking into account the impact of the above multiple loads on the transmission line, the lateral displacement of the transmission line can be expressed by the following equation:

[0039]

[0040] Where E is the Young's modulus of the transmission line material, I is the moment of inertia of the transmission line; d represents a differential symbol, indicating the change or derivative of a variable;

[0041] In S1, the vertical strain equation of the transmission line is:

[0042] The vertical strain of the transmission line can be expressed as:

[0043]

[0044] Where l is the actual length of each transmission line;

[0045] In S1, the strain distribution of the transmission line is obtained, which means:

[0046] ε total =y(x)+ε wind (x)+ε ice (x) (7)

[0047] Among them, ε totalis the total strain of the transmission line, ε wind (x) is the strain caused by wind pressure load, ε ice (x) is the strain caused by icing load;

[0048] In S1, the mechanical response equations of the transmission line in the horizontal and vertical directions are:

[0049] Combining various mechanical effects, the mechanical responses of the transmission line in the transverse and longitudinal directions can be jointly described by the following equations:

[0050]

[0051] This equation combines the geometric shape of the transmission line with the mechanical effects and provides a more accurate basis for subsequent electric field calculations.

[0052] Furthermore, in S2, the charge distribution of the transmission line is discretized into equivalent point charges, the equivalent point charge density is calculated, and an equivalent charge model is constructed. For each transmission line length Δl, the equivalent charge Q is calculated. eq , means:

[0053] First, define the charge density on the transmission line as λ(x). Assuming that the charge density varies with position x, it can be expressed by the following function:

[0054] λ(x)=λ0·(1+βx 2 ) (9)

[0055] Where λ0 is the baseline charge density, and β is the coefficient for adjusting the charge density change, indicating that the charge density changes with the change of x;

[0056] The charge distribution of the transmission line will be discretized into equivalent point charges, and an equivalent charge model will be constructed:

[0057] The length of each transmission line is Δl, and the equivalent charge is Q eq It can be obtained by integrating the charge density:

[0058]

[0059] Where x1 and x2 are the starting and ending positions of the charge distribution segment, respectively.

[0060] Furthermore, in S3, the equivalent charge model is used to calculate the electric field generated by each equivalent point charge at a certain point P(x, y, z) through Coulomb's law, which means:

[0061] Assuming r is the distance from the charge location to point P, the electric field E is:

[0062]

[0063] Where ε0 is the dielectric constant of vacuum, Q eq is the equivalent charge, r is the distance between the charge and point P; The unit vector that represents the direction of a point charge pointing to a point in space;

[0064] The electric field contributions of all equivalent charges are superimposed to obtain the sum of the electric fields at point P(x,y,z); for the superposition of multiple charge contributions, the sum of the electric fields is:

[0065]

[0066] Where n is the number of all equivalent charges, Q i is the magnitude of the ith equivalent charge, r i is the distance from the ith charge to point P.

[0067] Furthermore, in S3, the charge density is combined with the electric field calculation to obtain the integral expression of the electric field. The electric field calculation is expressed in the integral form of the charge density:

[0068]

[0069] The electric field is the integral of the contribution of the charge density λ(x) to the electric field, where r is the distance from the charge location to the observation point.

[0070] Furthermore, in S4, the electric field solution area is discretized into multiple small units, the potential expression in each unit is constructed, and the distribution of the potential in each unit is calculated by the inner product, which means:

[0071] The expression of the electric potential in the i-th unit is:

[0072]

[0073] Among them, φ j is the potential value of the jth node, N j (x, y, z) is the shape function of the jth node, and N is the number of nodes in the element;

[0074] By discretization, the weak form of Poisson's equation can be expressed as:

[0075]

[0076] Where Φ is the potential function, representing the electric potential at a point in space. Ψ is the test function, Ω represents the entire calculation area, and ρ(r) is the charge density function, representing the charge distribution at a point in space. ε is the dielectric constant, representing the electrical properties of the material and determining the relationship between the electric field and the electric potential. This equation describes the distribution of the electric potential within each cell by calculating the inner product.

[0077] In S4, the stiffness matrix K and load vector F of each unit are assembled. By combining the stiffness matrix and load vector of each unit according to their position, the stiffness matrix K of the entire system is obtained. total and the load vector F total ; means:

[0078] The stiffness matrix K of each element e and the load vector F e It is obtained by the following formula:

[0079]

[0080] Among them, N i 、N j is the shape function, Ω e is the unit area, ρ(r) is the charge density in space, ε is the dielectric constant, and the stiffness matrix K total and the load vector F total Reflects the distribution of electric potential in each unit;

[0081] By transforming the stiffness matrix K of each element total and the load vector F total Merge them according to their positions to get the stiffness matrix K of the entire system total and the load vector F total ; The equations of the entire system are:

[0082] K total Φ=F total (19)

[0083] Here, Φ is the column vector of node potentials, K total is the global stiffness matrix, F total is the global load vector;

[0084] Furthermore, in S4, by solving the algebraic equation K total Φ=F total , calculate the electric potential distribution Φ of the entire calculation area, and obtain the electric field strength, which means:

[0085] After obtaining the electric potential distribution Φ, the electric field E can be obtained by calculating the negative gradient of the electric potential:

[0086]

[0087] is the gradient operator. This electric field calculation gives the rate of change of the electric potential field, thereby obtaining the electric field strength.

[0088] A system for calculating the electric field around an ADSS optical cable, comprising:

[0089] Modeling module,

[0090] It simulates the geometry of the transmission line and constructs equations to describe its shape;

[0091] Construct the lateral displacement and vertical strain equations of the transmission line, the strain distribution of the transmission line, and the mechanical response equations of the transmission line in the lateral and longitudinal directions; construct an equivalent charge model;

[0092] Computing Module

[0093] Discretize the charge distribution of the transmission line into equivalent point charges, calculate the equivalent point charge density, and calculate the equivalent charge Q for each transmission line length Δl eq :

[0094] Calculate the electric field generated by each equivalent point charge at a certain point P(x,y,z) using Coulomb's law;

[0095] Solver Module

[0096] Calculate the distribution of electric potential of each unit in the solution area; combine the stiffness matrix and load vector of each unit according to its position, calculate the electric potential distribution Φ of the entire calculation area, and obtain the electric field strength;

[0097] The calculated electric field intensity is mapped to three-dimensional space through the interpolation function.

[0098] The calculated electric field can be mapped to three-dimensional space through post-processing. Assuming that the electric field is known at the node, the electric field intensity E(x,y,z) can be mapped to the entire calculation area through interpolation functions.

[0099] A computer device comprises: one or more processors; the processors are used to store one or more programs; when the one or more programs are executed by the one or more processors, the method for calculating the electric field around an ADSS optical cable is implemented.

[0100] A computer-readable storage medium stores a computer program, which, when executed, implements the method for calculating the electric field around an ADSS optical cable.

[0101] The present invention proposes a method, system, equipment and medium for calculating the electric field around ADSS optical cables based on the equivalent charge method and finite element analysis (FEM). By comprehensively considering the geometric shape and mechanical response of the transmission line, the electric field calculation is performed by combining the equivalent charge method with finite element analysis. While ensuring high calculation accuracy, this method can effectively reduce the consumption of computing resources and has high computational efficiency. Through this model, the electric field distribution around the optical cable can be simulated more accurately, providing reliable technical support for the design and safety assessment of ADSS optical cables, thereby improving the safety and reliability of the optical cable in different environments and working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0102] The various advantages of the present invention will be more clearly presented to researchers in the field through the more detailed embodiments described below. The accompanying drawings will serve as auxiliary explanations. The accompanying drawings are as follows:

[0103] Figure 1 Model the finite element geometry of transmission lines.

[0104] Figure 2 is the finite element mesh of the transmission line.

[0105] Figure 3 is the electric field distribution around the transmission line. DETAILED DESCRIPTION

[0106] S1: Transmission Line Structure Modeling

[0107] In order to accurately consider the deformation of transmission lines under different environmental conditions, the finite element method (FEM) is used to simulate the geometry and mechanical response of transmission lines.

[0108] Transmission lines are considered to consist of several segments, each of which deforms under the influence of external loads (such as wind pressure and icing). The finite element method is used to discretize each segment into a series of small units, and the geometry of each unit is dynamically adjusted according to its load state.

[0109] Consider a transmission line at each end of a tower. Under load, it forms a catenary shape. A catenary is the shape of a flexible object suspended between two points under the influence of gravity.

[0110] Model the geometry of transmission lines and construct equations to describe their shapes;

[0111] Assuming that the transmission line deforms in a plane, its shape can be described by the following equation:

[0112]

[0113] Where y(x) represents the height of the transmission line at position x, a is a constant calculated based on the weight of the transmission line and other loads, and cosh is the hyperbolic cosine function.

[0114] Taking into account the mechanical effects, it is necessary to further introduce elastic mechanics models to more accurately describe the response of the transmission line. The lateral displacement and vertical strain equations of the transmission line are constructed to obtain the strain distribution of the transmission line and the mechanical response equations of the transmission line in the lateral and longitudinal directions.

[0115] Assuming the cross section of the transmission line is circular, when subjected to wind pressure and ice load, the deformation of the transmission line is affected by the following factors:

[0116] Gravity effect: Assuming that the mass of each transmission line is m and the length is l, the bending moment caused by the gravity of the transmission line is:

[0117] M(x)=m·g·x(22)

[0118] Where g is the acceleration due to gravity and x is the horizontal position of the transmission line.

[0119] Wind pressure load: The impact of wind pressure load on transmission lines can be expressed by the following formula:

[0120] F wind (x) = C d ·ρ·A wind ·v 2 (x) (23)

[0121] Among them, C d is the drag coefficient, ρ is the air density, A wind is the frontal area of ​​the transmission line, and v(x) is the wind speed.

[0122] Ice load: Considering that snow or ice may accumulate on the surface of the transmission line, the surface load of the transmission line can be expressed as:

[0123] F ice (x)=σ ice ·A ice (twenty four)

[0124] Among them, σ ice is the density of ice, A ice is the area of ​​ice on the surface of the transmission line.

[0125] In order to comprehensively consider the impact of the above multiple loads on the transmission line, the lateral displacement of the transmission line can be expressed by the following equation:

[0126]

[0127] Where E is the Young's modulus of the transmission line material, and I is the moment of inertia of the transmission line.

[0128] This equation describes the bending response of the transmission line under external loads. By solving this equation, the lateral displacement of the transmission line can be obtained (i.e., an accurate model of the catenary).

[0129] According to the mechanical equations mentioned above, the effective parameters of the catenary model can be further derived

[0130] First, the vertical strain of the transmission line can be expressed as:

[0131]

[0132] Where l is the actual length of each transmission line section.

[0133] Then, through the combination of these parameters, the deformation and strain distribution of the entire transmission line can be obtained. The strain distribution of the transmission line can be expressed by the following equation:

[0134] ε total =y(x)+ε wind (x)+ε ice (x) (7)

[0135] Among them, ε total is the total strain of the transmission line, ε wind (x) is the strain caused by wind pressure load, ε ice (x) is the strain caused by icing load;

[0136] Combining various mechanical effects, the mechanical responses of the transmission line in the transverse and longitudinal directions can be jointly described by the following equations:

[0137]

[0138] This equation combines the geometric shape of the transmission line with the mechanical effects and provides a more accurate basis for subsequent electric field calculations.

[0139] S2: Calculate the charge distribution of transmission lines and construct an equivalent charge model

[0140] For transmission lines, the charge distribution can be viewed as a continuous or discrete linear charge distribution. First, the charge density on the transmission line is defined as λ(x), and the variation of the charge density with position is calculated based on the physical model.

[0141] Charge density model: Assuming that the charge density varies with position x, it can be represented by the following function:

[0142] λ(x)=λ0·(1+βx 2 ) (29)

[0143] Where λ0 is the baseline charge density and β is the coefficient that adjusts the charge density, indicating how the charge density changes with changes in x. This model takes into account the unevenness of charge distribution, especially the difference in electric field strength at different parts of the transmission line.

[0144] The present invention uses the finite element method to discretize each section of the transmission line into a series of small units. In order to simplify the calculation, the charge distribution of the transmission line is discretized into equivalent point charges, the equivalent point charge density is calculated, and an equivalent charge model is constructed. For each section of the transmission line length Δl, the equivalent charge Q is calculated. eq :

[0145] Equivalent charge: the charge per length Q eq It can be obtained by integrating the charge density:

[0146]

[0147] Where x1 and x2 are the starting and ending positions of the charge distribution segment, respectively. This formula takes into account the variation of charge density with position and uses integration to obtain the equivalent charge.

[0148] S3: Using the equivalent charge model, calculate the electric field generated by each equivalent point charge at a certain point P(x,y,z) using Coulomb's law;

[0149] Assuming r is the distance from the charge location to point P, the electric field E is:

[0150]

[0151] Where ε0 is the dielectric constant of vacuum, Q eq is the equivalent charge, and r is the distance between the charge and point P.

[0152] The electric field contributions of all equivalent charges are superimposed to obtain the total electric field at point P(x,y,z). For the superposition of multiple charge contributions, the total electric field is:

[0153]

[0154] Where n is the number of all equivalent charges, Q i is the magnitude of the ith equivalent charge, r i is the distance from the ith charge to point P.

[0155] In order to describe the electric field more accurately, the charge density can be combined with the electric field calculation to obtain the integral expression of the electric field. The electric field calculation can be expressed in the integral form of the charge density:

[0156]

[0157] The electric field is the integral of the contribution of the charge density λ(x) to the electric field, where r is the distance from the charge location to the observation point.

[0158] S4: Finite element analysis to solve the electric field

[0159] The electric field solution area is discretized into multiple small units, the electric potential expression in each unit is constructed, and the distribution of electric potential in each unit is calculated by the inner product;

[0160] First, the core of the finite element method is to solve the Poisson equation. In the electrostatic field, the relationship between the potential function Φ and the charge distribution ρ is given by the Poisson equation:

[0161]

[0162] where Φ(r) is the electric potential function, ρ(r) is the charge density in space, and ε is the dielectric constant. is the Laplace operator, which represents the second-order derivative of the electric potential in space.

[0163] The relationship between the electric field E and the electric potential Φ is defined by its gradient:

[0164]

[0165] This formula states that the electric field is the negative gradient of the electric potential. By solving for the electric potential Φ, the electric field distribution can be directly calculated.

[0166] The present invention uses the finite element method to discretize the solution area into multiple small units. The potential function on each unit is approximated by a linear combination of node values. The expression of the potential in the i-th unit is:

[0167]

[0168] Among them, φ j is the potential value of the jth node, N j (x, y, z) is the shape function of the jth node, and N is the number of nodes in the element.

[0169] By discretization, the weak form of Poisson's equation can be expressed as:

[0170]

[0171] Where Ψ is the test function and Ω represents the entire computational domain. This equation describes the distribution of the potential within each cell by calculating the inner product.

[0172] The core of finite element analysis is to assemble the stiffness matrix K and the load vector F, and obtain the node potential by solving the algebraic equation KΦ=F.

[0173] The stiffness matrix K of each unit of the present invention is e and the load vector F e It can be obtained by the following formula:

[0174]

[0175] Among them, N i 、N j is the shape function, Ω e is the unit area, ρ(r) is the charge density in space, ε is the dielectric constant, and the stiffness matrix K total and the load vector F total Reflects the distribution of electric potential in each unit;

[0176] The stiffness matrix K of the entire system is obtained by combining the stiffness matrix and load vector of each element according to its position. total and the load vector F total The equations for the entire system are:

[0177] K total Φ=F total (39)

[0178] Here, Φ is the column vector of node potentials, K total is the global stiffness matrix, F total is the global load vector.

[0179] By solving the algebraic equation K total Φ=F total , the electric potential distribution Φ of the entire calculation area can be obtained. After obtaining the electric potential, the electric field E can be obtained by calculating the negative gradient of the electric potential:

[0180]

[0181] This electric field calculation gives the rate of change of the electric potential field, and thus the electric field strength.

[0182] S5: The calculated electric field intensity is mapped to the three-dimensional space around the transmission line, and the electric field distribution is mapped around the optical cable according to the position and geometry of the optical cable.

[0183] Finally, the calculated electric field can be mapped to three-dimensional space through post-processing. Assuming that the electric field is known at the node, the electric field intensity E(x,y,z) can be mapped to the entire calculation area through an interpolation function.

[0184] Specifically, the calculated distribution of electric field intensity at the nodes of the finite element mesh is spatially interpolated using an interpolation function, resulting in the electric field distribution in the entire three-dimensional space around the transmission line. This process ensures that the variations in electric field intensity at different locations (including the space around the transmission line and the area near the optical cable) can be accurately represented, providing basic data for subsequent safety assessment and design.

[0185] This method first calculates the electric field distribution around the transmission line and then maps this electric field distribution around the cable based on the cable's position and geometry. Because ADSS cables are typically suspended over high-voltage transmission lines, the electric field they experience is determined by the electric field of the transmission line. This method accurately infers the electric field distribution around the cable, allowing for the assessment of its electrical performance and safety.

[0186] An electric field calculation system around an ADSS optical cable, comprising:

[0187] Modeling module,

[0188] It simulates the geometry of the transmission line and constructs equations to describe its shape;

[0189] Construct the lateral displacement and vertical strain equations of the transmission line, the strain distribution of the transmission line, and the mechanical response equations of the transmission line in the lateral and longitudinal directions; construct an equivalent charge model;

[0190] Computing Module

[0191] Discretize the charge distribution of the transmission line into equivalent point charges, calculate the equivalent point charge density, and calculate the equivalent charge Q for each transmission line length Δl eq :

[0192] Calculate the electric field generated by each equivalent point charge at a certain point P(x,y,z) using Coulomb's law;

[0193] Solver Module

[0194] Calculate the distribution of electric potential of each unit in the solution area; combine the stiffness matrix and load vector of each unit according to its position, calculate the electric potential distribution Φ of the entire calculation area, and obtain the electric field strength;

[0195] The calculated electric field intensity is mapped to three-dimensional space through the interpolation function.

[0196] A computer device comprising: one or more processors; the processors being configured to store one or more programs; and when the one or more programs are executed by the one or more processors, a method for calculating the electric field around an ADSS optical cable as described in any one of claims 1 to 7 is implemented.

[0197] A computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed, the method for calculating the electric field around an ADSS optical cable according to any one of claims 1 to 7 is implemented.

[0198] It should be emphasized that the embodiments described in the present invention are illustrative rather than restrictive. Therefore, the present invention includes but is not limited to the embodiments described in the specific implementation manner, and all those derived by those skilled in the art based on the technical solutions of the present invention.

Claims

1. A method for calculating the electric field around an ADSS optical cable, characterized in that: The specific steps are: S1: Transmission Line Structure Modeling Model the geometry of transmission lines and construct equations to describe their shapes; By introducing the elastic mechanics model, the lateral displacement and vertical strain equations of the transmission line are constructed, and the strain distribution of the transmission line and the mechanical response equations of the transmission line in the lateral and longitudinal directions are obtained; S2: Calculate the charge distribution of transmission lines and construct an equivalent charge model Use the finite element method to discretize each section of the transmission line into a series of small units, discretize the charge distribution of the transmission line into equivalent point charges, calculate the equivalent point charge density, construct an equivalent charge model, and calculate the equivalent charge Q for each section of the transmission line length Δl. eq : S3: Using the equivalent charge model, calculate the electric field generated by each equivalent point charge at a certain point P(x,y,z) using Coulomb's law; S4: Finite element analysis to solve the electric field The electric field solution area is discretized into multiple small units, the electric potential expression in each unit is constructed, and the distribution of electric potential in each unit is calculated by the inner product; Assemble the stiffness matrix K and load vector F of each unit, and obtain the stiffness matrix K of the entire system by combining the stiffness matrix and load vector of each unit according to their position total and the load vector F total ; By solving the algebraic equation K total Φ=F total , calculate the electric potential distribution Φ of the entire calculation area and obtain the electric field intensity; S5: The calculated electric field intensity is mapped to the three-dimensional space around the transmission line, and the electric field distribution is mapped around the optical cable according to the position and geometry of the optical cable.

2. The method for calculating the electric field around an ADSS optical cable according to claim 1, wherein: In S1, simulating the geometry of the transmission line and constructing equations to describe its shape means: The transmission lines at both ends of the tower will form a catenary shape after being subjected to force. Assuming that the transmission line deforms in a plane, its shape can be described by the following equation: Where y(x) represents the height of the transmission line at position x, a is a constant calculated based on the weight of the transmission line and other loads, and cosh is the hyperbolic cosine function.

3. The method for calculating the electric field around an ADSS optical cable according to claim 1, wherein: In S1, the lateral displacement of the transmission line is constructed as follows: An elastic mechanics model is introduced to accurately describe the response of the transmission line. The cross section of the transmission line is assumed to be circular. When subjected to wind pressure and ice loads, the deformation of the transmission line is affected by the following factors: Gravity effect: Assuming that the mass of each transmission line is m and the length is l, the bending moment caused by the gravity of the transmission line is: M(x)=m·g·x (2) Where g is the acceleration of gravity, x is the horizontal position of the transmission line, and M(x) is the bending moment; Wind pressure load: The impact of wind pressure load on transmission lines can be expressed by the following formula: F wind (x)=C d ·ρ·A wind ·v 2 (x) (3) Among them, C d is the drag coefficient, ρ is the air density, A wind is the frontal area of ​​the transmission line, v(x) is the wind speed, F wind (x) is the wind pressure load; Ice load: Considering that snow or ice may accumulate on the surface of the transmission line, the surface load of the transmission line can be expressed as: F ice (x)=σ ice ·A ice (4) Among them, σ ice is the density of ice, A ice is the ice area on the transmission line surface, F ice (x) is the surface load of the transmission line; Taking into account the impact of the above multiple loads on the transmission line, the lateral displacement of the transmission line can be expressed by the following equation: Where E is the Young's modulus of the transmission line material, I is the moment of inertia of the transmission line; d represents a differential symbol, indicating the change or derivative of a variable; In S1, the vertical strain equation of the transmission line is: The vertical strain of the transmission line can be expressed as: Where l is the actual length of each transmission line; In S1, the strain distribution of the transmission line is obtained, which means: e total =y(x)+ε wind (x)+e ice (x) (7) Among them, ε total is the total strain of the transmission line, ε wind (x) is the strain caused by wind pressure load, ε ice (x) is the strain caused by icing load; In S1, the mechanical response equations of the transmission line in the horizontal and vertical directions are: Combining various mechanical effects, the mechanical responses of the transmission line in the transverse and longitudinal directions can be jointly described by the following equations: This equation combines the geometric shape of the transmission line with the mechanical effects and provides a more accurate basis for subsequent electric field calculations.

4. The method for calculating the electric field around an ADSS optical cable according to claim 1, wherein: In S2, the charge distribution of the transmission line is discretized into equivalent point charges, the equivalent point charge density is calculated, and an equivalent charge model is constructed. For each transmission line length Δl, the equivalent charge Q is calculated. eq , means: First, define the charge density on the transmission line as λ(x). Assuming that the charge density varies with position x, it can be expressed by the following function: λ(x)=λ0·(1+βx 2 ) (9) Where λ0 is the baseline charge density, and β is the coefficient for adjusting the charge density change, indicating that the charge density changes with the change of x; The charge distribution of the transmission line will be discretized into equivalent point charges, and an equivalent charge model will be constructed: The length of each transmission line is Δl, and the equivalent charge is Q eq It can be obtained by integrating the charge density: Where x1 and x2 are the starting and ending positions of the charge distribution segment, respectively.

5. The method for calculating the electric field around an ADSS optical cable according to claim 1, wherein: In S3, the equivalent charge model is used to calculate the electric field generated by each equivalent point charge at a certain point P(x,y,z) using Coulomb's law, which means: Assuming r is the distance from the charge location to point P, the electric field E is: Where ε0 is the dielectric constant of vacuum, Q eq is the equivalent charge, r is the distance between the charge and point P; The unit vector that represents the direction of a point charge pointing to a point in space; The electric field contributions of all equivalent charges are superimposed to obtain the sum of the electric fields at point P(x,y,z); for the superposition of multiple charge contributions, the sum of the electric fields is: Where n is the number of all equivalent charges, Q i is the magnitude of the ith equivalent charge, r i is the distance from the ith charge to point P.

6. The method for calculating the electric field around an ADSS optical cable according to claim 4, wherein: In S3, the charge density is combined with the electric field calculation to obtain the integral expression of the electric field. The electric field calculation is expressed in the integral form of the charge density: The electric field is the integral of the contribution of the charge density λ(x) to the electric field, where r is the distance from the charge location to the observation point.

7. The method for calculating the electric field around an ADSS optical cable according to claim 1, wherein: In S4, the electric field solution area is discretized into multiple small units, the potential expression in each unit is constructed, and the distribution of the potential in each unit is calculated by the inner product, which means: The expression of the electric potential in the i-th unit is: Among them, φ j is the potential value of the jth node, N j (x, y, z) is the shape function of the jth node, and N is the number of nodes in the element; By discretization, the weak form of Poisson's equation can be expressed as: Where Φ is the potential function, which represents the potential at a point in space, Ψ is the test function, Ω represents the entire calculation area, ρ(r) is the charge density function, which represents the charge distribution at a point in space, and ε is the dielectric constant, which represents the electrical properties of the material and determines the relationship between the electric field and the potential. This equation describes the distribution of the potential within each cell by calculating the inner product. In S4, the stiffness matrix K and load vector F of each unit are assembled. By combining the stiffness matrix and load vector of each unit according to their position, the stiffness matrix K of the entire system is obtained. total and the load vector F total ; means: The stiffness matrix K of each element e and the load vector F e It is obtained by the following formula: Among them, N i 、N j is the shape function, Ω e is the unit area, ρ(r) is the charge density in space, ε is the dielectric constant, and the stiffness matrix K total and the load vector F total Reflects the distribution of electric potential in each unit; By transforming the stiffness matrix K of each element total and the load vector F total Merge them according to their positions to get the stiffness matrix K of the entire system total and the load vector F total ; The equations of the entire system are: K total Φ=F total (19) Here, Φ is the column vector of node potentials, K total is the global stiffness matrix, F total is the global load vector.

8. The method for calculating the electric field around an ADSS optical cable according to claim 1 or 6, wherein: In S4, by solving the algebraic equation K total Φ=F total , calculate the electric potential distribution Φ of the entire calculation area, and obtain the electric field strength, which means: After obtaining the electric potential distribution Φ, the electric field E can be obtained by calculating the negative gradient of the electric potential: ▽ is the gradient operator. This electric field calculation gives the rate of change of the electric potential field, thereby obtaining the electric field strength.

9. A system for calculating the electric field around an ADSS optical cable, characterized in that: include: Modeling module, It simulates the geometry of the transmission line and constructs equations to describe its shape; Construct the lateral displacement and vertical strain equations of the transmission line, as well as the strain distribution and mechanical response equations of the transmission line in the lateral and longitudinal directions; Construct an equivalent charge model; Computing Module Discretize the charge distribution of the transmission line into equivalent point charges, calculate the equivalent point charge density, and calculate the equivalent charge Q for each transmission line length Δl eq : Calculate the electric field generated by each equivalent point charge at a certain point P(x,y,z) using Coulomb's law; Solver Module Calculate the distribution of electric potential of each unit in the solution area; combine the stiffness matrix and load vector of each unit according to its position, calculate the electric potential distribution Φ of the entire calculation area, and obtain the electric field strength; The calculated electric field intensity is mapped to three-dimensional space through the interpolation function.

10. A computer device, characterized in that: include: one or more processors; The processor is configured to store one or more programs; When the one or more programs are executed by the one or more processors, the method for calculating the electric field around an ADSS optical cable according to any one of claims 1 to 7 is implemented.

11. A computer-readable storage medium, characterized in that A computer program is stored thereon, and when the computer program is executed, a method for calculating the electric field around an ADSS optical cable as described in any one of claims 1 to 7 is implemented.

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