Method and system for calculating wind load of power distribution conductor under tornado action and storage medium

Abstract

The invention discloses a calculation method and system for a power distribution wire wind load under the tornado effect and a storage medium. The method comprises the steps that a tornado wind field model is constructed, and a wind field is simplified into dominant tangential wind speed distribution; extracting the center position of the lead section under the span configuration, and measuring the radial space relation of the center position relative to the tornado center; establishing a wind load integral calculation model of each span section of the conductor, and calculating aerodynamic load distribution of conductors of adjacent spans; through load direction decomposition and structural stress analysis, the aerodynamic force of the wire is converted into an external load of the distribution pole structure; and superposing the wire transmission load and the rod body wind pressure, and calculating the total wind load response of the power distribution rod. And accurate modeling and distribution of the aerodynamic force of the wire in the space and structure levels are realized. The method is suitable for power distribution line wind load analysis under the action of local strong wind such as tornado, and fine input parameters are provided for power distribution system structure safety evaluation.

Description

Technical Field

[0001] This invention belongs to the field of power system structural wind engineering technology. This invention relates to a method, system and storage medium for calculating wind load on power distribution conductors under the action of tornadoes. Background Technology

[0002] Tornadoes are characterized by their small scale, sudden onset, high wind speeds, short duration, and drastic wind field changes, posing a serious threat to linear infrastructure such as power distribution lines. Due to the complex structure of tornado wind fields and the large spatial gradient of wind speeds, conventional monitoring systems struggle to obtain effective wind speed data in real time, significantly increasing the uncertainty in wind load calculations and consequently affecting the scientific validity of structural design and post-disaster assessments. Post-disaster surveys show that power distribution lines, as typical indicators of wind-induced damage, experience significant tangential and radial wind speed coupling effects under tornado wind fields. Especially near the eye of the storm, the wind load distribution on these lines exhibits strong non-uniformity, far exceeding the load characteristics under normal calm wind conditions.

[0003] Existing calculation models generally ignore the aerodynamic differences of conductors at different horizontal positions, often estimating conductor loads using the average static pressure method, failing to reflect their spatial distribution characteristics. Simultaneously, wind loads on conductors are transferred to distribution poles through insulators, generating additional wind loads on the pole structure. Traditional analyses mostly focus only on the wind pressure within the pole itself, and currently lack a wind load calculation method that can systematically consider the wind load transfer effect of conductors. Therefore, there is an urgent need to establish a calculation method that considers the structure of tornado wind fields, the relative positional relationship between conductors and the wind field, and the distribution characteristics of conductor wind loads, to improve the accuracy and reliability of wind load assessment for distribution structures under tornadoes. Summary of the Invention

[0004] The purpose of this invention is to provide a method, system, and storage medium for calculating the wind load on power distribution conductors under tornado conditions. The calculation method takes into account the structure of the tornado wind field, the relative positional relationship between the conductor and the wind field, and the distribution characteristics of the conductor wind load. This method can improve the accuracy and reliability of the wind load assessment of power distribution structures under tornado conditions.

[0005] The technical solution to achieve the purpose of this invention is as follows: A method for calculating the wind load on power distribution conductors under the action of a tornado includes the following steps: A tornado wind field model was constructed, simplifying the wind field to the dominant tangential wind speed distribution; the center position of the conductor segment under the span configuration was extracted, and its radial spatial relationship with the tornado center was determined to determine the position of the conductor relative to the wind field. Establish wind load integral calculation models for each span of the conductor, and calculate the aerodynamic forces of the conductor under the action of tornado based on the established wind load integral calculation models. By decomposing the load direction and analyzing the structural stress, the aerodynamic force of the conductor is converted into the wind load of the distribution pole. The total wind load response of the distribution pole is obtained by superimposing the wind load transmitted by the conductor on the pole body.

[0006] In the preferred technical solution, constructing the tornado wind field model includes: A two-dimensional Rankine vortex model was used to establish the tornado wind speed distribution model. The variation of wind speed with height and the influence of radial wind speed components were ignored. Only the force characteristics of the conductor under tangential wind speed were considered. The wind speed model is as follows:

[0007] In the formula: Radial position from the center of the tornado r Tangential wind speed at that location V m This is the maximum tangential wind speed of a tornado. r c This represents the radial distance corresponding to the point of maximum tangential wind speed.

[0008] In the preferred technical solution, determining its radial spatial relationship relative to the tornado center includes: By combining the relative position of the power line spans with the tornado wind field, the wind speed distribution, and the direction of wind load, the conductor span sections within the tornado's influence area are identified, and the vertical distance between the tornado center and the conductors is determined. d The point where the conductor experiences the strongest wind in the wind speed distribution. Expressed as:

[0009] in, This is the horizontal distance from the starting point of the conductor to the point of maximum wind speed, used to define the starting point location of the wind load integration.

[0010] In the preferred technical solution, the wind load integral calculation model for each span of the conductor includes: A distributed wind load calculation model is established. Based on aerodynamic theory, the formula for calculating the wind load per unit length of conductor is as follows:

[0011] in, Where is air density, G is gust factor, and C is air density. f The drag coefficient is affected by the Reynolds number and can be determined by referring to a table. D is the conductor diameter. For wires x Wind speed at the location; The aerodynamic expressions for wind loads on conductors of each span are obtained by integration:

[0012] in,L This refers to the span of a single conductor segment.

[0013] In the preferred technical solution, the aerodynamic forces acting on the tornado's conductor are calculated as follows: Calculate the lateral force on the damaged distribution pole caused by the aerodynamic forces of all conductor segments; By summing the values ​​of all conductor segments, the total lateral force caused by the aerodynamic forces on the conductors due to the tornado is obtained as follows: .

[0014] In the preferred technical solution, converting the aerodynamic force of the conductor into the wind load of the distribution pole includes: Based on the angle between the guide wire and the direction of the tornado's rotation α The aerodynamic force is decomposed into two components: tangential and radial.

[0015] In the formula, and These represent the loads on the distribution poles in the tangential and radial directions caused by the aerodynamic lateral force of the conductors during the tornado.

[0016] In the preferred technical solution, superimposing the wind load on the distribution pole transmitted by the conductor with the wind pressure on the pole body includes: The additional bending moment generated by the wind load on the conductor is linearly superimposed with the wind pressure bending moment of the pole body in two main directions to obtain the total base bending moment of the distribution pole under the action of the tornado wind field, and then the structural safety assessment or wind load inversion analysis is carried out.

[0017] This invention also discloses a calculation system for wind load on power distribution conductors under tornado conditions, comprising: The tornado wind field model building module constructs a tornado wind field model, simplifies the wind field to the dominant tangential wind speed distribution; extracts the center position of the conductor segment under the span configuration, and determines its radial spatial relationship with the tornado center to determine the position of the conductor relative to the wind field. The conductor wind load integral model construction module establishes a wind load integral calculation model for each span of the conductor, and calculates the aerodynamic force of the conductor under the action of a tornado based on the established wind load integral calculation model. The wind load direction component analysis module converts the aerodynamic force of the conductor into the wind load of the distribution pole through load direction decomposition and structural stress analysis. The wind load assessment module superimposes the wind load transmitted by the conductors on the distribution pole with the wind pressure on the pole itself to obtain the total wind load response of the distribution pole.

[0018] The present invention also discloses a computer storage medium storing a computer program, wherein when the computer executes the computer program, it implements the method for calculating the wind load on power distribution conductors under the action of a tornado as described in any of the above claims.

[0019] Compared with the prior art, the significant advantages of this invention are: A calculation method considering the structure of tornado wind fields, the relative positional relationship between conductors and the wind field, and the wind load distribution characteristics of conductors is developed. This method enables accurate modeling and distribution of conductor aerodynamic forces at both spatial and structural levels, improving the accuracy and reliability of wind load assessment for power distribution structures under tornado conditions. This method is applicable to wind load analysis of power distribution lines under the influence of localized strong winds such as tornadoes, providing refined input parameters for the structural safety assessment of power distribution systems. Attached Figure Description

[0020] Figure 1 A flowchart illustrating the calculation method for wind load on power distribution conductors under the influence of a tornado; Figure 2 A schematic diagram of the tornado's path and disaster assessment; Figure 3 A schematic diagram of a calculation model for wind load on power distribution conductors under the action of a tornado; Figure 4 The diagram shows the aerodynamic calculation results caused by wind load on the conductor. Figure 5 The diagram shows the calculated wind speed at a height of 10 meters, taking into account the failure of power distribution lines. Detailed Implementation

[0021] The principle of this invention is as follows: a tornado wind speed distribution field is constructed based on a two-dimensional Rankine vortex model. The aerodynamic load distribution of adjacent span conductors is calculated by combining the relative radial position of the conductor and the center of the tornado. The wind load of the conductor is distributed to the position of the distribution pole using the principle of shear influence line of simply supported beam. This is superimposed with the wind pressure on the distribution pole body to form a mapping relationship between the spatial distribution of the conductor wind load and the aerodynamic response of the distribution pole, thereby realizing the accurate calculation of the total wind load of the distribution line under the tornado wind field.

[0022] Example: like Figure 1 As shown, a method for calculating the wind load on power distribution conductors under the action of a tornado includes the following steps: A tornado wind field model was constructed, simplifying the wind field to the dominant tangential wind speed distribution; the center position of the conductor segment under the span configuration was extracted, and its radial spatial relationship with the tornado center was determined to determine the position of the conductor relative to the wind field. Establish wind load integral calculation models for each span of the conductor, and calculate the aerodynamic forces of the conductor under the action of tornado based on the established wind load integral calculation models. By decomposing the load direction and analyzing the structural stress, the aerodynamic force of the conductor is converted into the wind load of the distribution pole. The total wind load response of the distribution pole is obtained by superimposing the wind load transmitted by the conductor on the pole body.

[0023] In a preferred embodiment, constructing a tornado wind field model includes: A two-dimensional Rankine vortex model was used to establish the tornado wind speed distribution model. The variation of wind speed with height and the influence of radial wind speed components were ignored. Only the force characteristics of the conductor under tangential wind speed were considered. The wind speed model is as follows:

[0024] In the formula: Radial position from the center of the tornado r Tangential wind speed at that location V m This is the maximum tangential wind speed of a tornado. r c This represents the radial distance corresponding to the point of maximum tangential wind speed.

[0025] In a preferred embodiment, determining its radial spatial relationship relative to the tornado center includes: By combining the relative position of the power line spans with the tornado wind field, the wind speed distribution, and the direction of wind load, the conductor span sections within the tornado's influence area are identified, and the vertical distance between the tornado center and the conductors is determined. d The point where the conductor experiences the strongest wind in the wind speed distribution. Expressed as:

[0026] in, This is the horizontal distance from the starting point of the conductor to the point of maximum wind speed, used to define the starting point location of the wind load integration.

[0027] In a preferred embodiment, the wind load integral calculation model for each span of the conductor includes: A distributed wind load calculation model is established. Based on aerodynamic theory, the formula for calculating the wind load per unit length of conductor is as follows:

[0028] in, Where is air density, G is gust factor, and C is air density. f The drag coefficient is affected by the Reynolds number and can be determined by referring to a table. D is the conductor diameter. For wires x Wind speed at the location; The aerodynamic expressions for wind loads on conductors of each span are obtained by integration:

[0029] in, L This refers to the span of a single conductor segment.

[0030] In a preferred embodiment, the aerodynamic forces acting on the tornado conductor are calculated as follows: Calculate the lateral force on the damaged distribution pole caused by the aerodynamic forces of all conductor segments; By summing the values ​​of all conductor segments, the total lateral force caused by the aerodynamic forces on the conductors due to the tornado is obtained as follows: .

[0031] In a preferred embodiment, converting the aerodynamic forces of the conductor into wind loads on the pole includes: Based on the angle between the guide wire and the direction of the tornado's rotation α The aerodynamic force is decomposed into two components: tangential and radial.

[0032] In the formula, and These represent the loads on the distribution poles in the tangential and radial directions caused by the aerodynamic lateral force of the conductors during the tornado.

[0033] In a preferred embodiment, superimposing the wind load on the distribution pole transmitted by the conductor with the wind pressure on the pole body includes: The additional bending moment generated by the wind load on the conductor is linearly superimposed with the wind pressure bending moment of the pole body in two main directions to obtain the total base bending moment of the distribution pole under the action of the tornado wind field, and then the structural safety assessment or wind load inversion analysis is carried out.

[0034] In another embodiment, a calculation system for wind load on power distribution conductors under tornado conditions includes: The tornado wind field model building module constructs a tornado wind field model, simplifies the wind field to the dominant tangential wind speed distribution; extracts the center position of the conductor segment under the span configuration, and determines its radial spatial relationship with the tornado center to determine the position of the conductor relative to the wind field. The conductor wind load integral model construction module establishes a wind load integral calculation model for each span of the conductor, and calculates the aerodynamic force of the conductor under the action of a tornado based on the established wind load integral calculation model. The wind load direction component analysis module converts the aerodynamic force of the conductor into the wind load of the distribution pole through load direction decomposition and structural stress analysis. The wind load assessment module superimposes the wind load transmitted by the conductors on the distribution pole with the wind pressure on the pole itself to obtain the total wind load response of the distribution pole.

[0035] The following example illustrates the workflow of the calculation system for wind load on power distribution conductors under tornado conditions, including the following steps: Step 1: Construct a tornado wind field model. The specific process is as follows: In the modeling process, based on the typical rotating vortex characteristics of tornadoes, a tornado wind speed distribution model based on the two-dimensional Rankine vortex model is constructed. The variation of wind speed with height and the influence of radial wind speed components are ignored, and only the force characteristics of the conductor under tangential wind speed are considered. At the same time, the relative radial position of the conductor and the center of the tornado is determined to obtain its wind characteristics. The wind speed model is as follows:

[0036] In the formula: Radial position from the center of the tornado r Tangential wind speed at the location; V m This is the maximum tangential wind speed of a tornado; r c This represents the radial distance corresponding to the point of maximum tangential wind speed.

[0037] When the location of the conductor is less than the center of the tornado r c When the tangential wind speed increases linearly with radial distance, when it is greater than 1000 km / h, the tangential wind speed increases linearly with radial distance; when it is greater than 1000 km / h, the tangential wind speed increases linearly with radial distance. r c At that time, the tangential wind speed decreases inversely with the radial distance.

[0038] It should be noted that, as Figure 2 As shown, the maximum tangential wind speed range corresponding to different levels of tornadoes can be determined based on the wind field intensity from the disaster survey and assessment, combined with existing data. V m The magnitude of the value can be determined by the approximate path of the tornado and the distribution of its destructive extent. r c value.

[0039] Step 2: Determine the position of the conductor relative to the wind field. The specific process is as follows: Within the span between two adjacent power distribution lines, there are a total of three power distribution poles, such as... Figure 3 As shown, the letters are A, B, and E. An intermediate power distribution pole was damaged, and pole B is the damaged pole. Based on its relative position to the tornado's wind field, wind speed distribution, and wind load direction, with point C as the center, four conductor spans within the tornado's influence area are identified: L AB ,L BC , L CD , L DE Determine the vertical distance between the tornado center and the guide wire. d Define the point where the conductor experiences the strongest wind in the wind speed distribution. , represented as:

[0040] in, It is the horizontal distance from the starting point of the conductor to the point of maximum wind speed, used to define the starting point of the wind load integration.

[0041] Step 3: Establish the integral model of the conductor wind load. The specific process is as follows: (1) Considering the non-uniformity of wind speed along the conductor direction, a distributed wind load calculation model is established. Based on aerodynamic theory, the formula for calculating the wind load per unit length of the conductor is:

[0042] in, air density; G is the gust factor; C f D is the drag coefficient, which is affected by the Reynolds number and can be determined by referring to a table; D is the conductor diameter. For wires x Wind speed at the location.

[0043] (2) An integral yields the aerodynamic expression for the wind load on a certain section of the conductor:

[0044] Specifically, for the damaged distribution pole B, the formula for calculating the wind load on the four conductor segments is as follows: L AB Lateral force on damaged distribution pole B caused by aerodynamic forces of the conductor segment:

[0045] L BC Lateral force on damaged distribution pole B caused by aerodynamic forces of the conductor segment:

[0046] L CD Lateral force on damaged distribution pole B caused by aerodynamic forces of the conductor segment:

[0047] L DE Lateral force B on the damaged distribution pole caused by the aerodynamic forces of the conductor segment:

[0048] In the formula, L This refers to the span of a single conductor segment.

[0049] (3) By summing the values ​​of the four conductor segments, the total lateral force caused by the aerodynamic forces on the conductors due to the tornado is obtained as follows:

[0050] After solving the integral, we get:

[0051] The fourth step is to analyze the directional components of the wind load. The specific process is as follows: Based on the angle between the guide wire and the direction of the tornado's rotation α The aerodynamic force is decomposed into two components: tangential and radial.

[0052] In the formula, and These represent the loads on the distribution poles in the tangential and radial directions caused by the aerodynamic lateral force of the conductors during the tornado. This is equivalent to the angle between the conductor and the tangent of the tornado.

[0053] Step 5: Superimpose the load transmitted by the conductor and the wind pressure of the pole body to calculate the total wind load response of the distribution pole.

[0054] The additional bending moment generated by the wind load on the conductor is linearly superimposed with the wind pressure bending moment of the pole body in two main directions to obtain the total base bending moment of the distribution pole under the action of the tornado wind field, which is used for structural safety assessment or wind load inversion analysis.

[0055] One possible implementation, the specific calculations of which are described below in the embodiment for power line damage caused by an actual EF2 level tornado, will not be repeated here.

[0056] The following is an example of power line damage caused by an actual EF2 level tornado: Step 1: Based on the location of damaged power poles, signs of wind-induced damage, and trajectory characteristics obtained from the post-disaster investigation, combined with... Figure 2 The indicated path confirms the tornado wind field model and key parameters. The specific process is as follows: Considering the typical rotating vortex characteristics of tornadoes, a two-dimensional Rankine vortex model is used to construct a tangential wind speed distribution model for tornadoes. The Rankine vortex model divides the entire wind field into a core region and an outer region: when When, the tangential wind speed increases linearly; when When the tangential wind speed decreases inversely, the wind speed expression is:

[0057] Based on the research data, Radial position from the center of the tornado r Tangential wind speed at 20 m; the radius corresponding to the maximum tangential wind speed is r c =50 m, calculated from this r / r c =0.4. The conductor is 6 m above the ground. Establish the wind speed-structural mechanics correlation and select the maximum tangential wind speed. The calculation is performed using multiple discrete values ​​of m / s.

[0058] Step 2: Determine the position of the conductor relative to the wind field. The specific process is as follows: like Figure 3 As shown, there are three distribution poles within the span of two adjacent distribution lines, designated by the letters A, B, and E. Assuming the middle distribution pole is damaged, and pole B is the damaged pole, considering its relative position to the tornado's wind field, wind speed distribution, and wind load direction, with point C as the center, identify four conductor spans within the tornado's influence area: L AB , L BC , L CD , L DE Determine the vertical distance between the tornado center and the guide wire. d = 20 m. Define the point where the conductor experiences the strongest wind in the wind speed distribution. , represented as:

[0059] Among them, the horizontal distance from the starting point of the guide wire to the point of maximum wind speed: .

[0060] Step 3: Establish the integral model of the conductor wind load. The specific process is as follows: (1) Considering the non-uniformity of wind speed along the conductor direction, a distributed wind load calculation model is established. Based on aerodynamic theory, the formula for calculating the wind load per unit length of the conductor is:

[0061] Among them, air density Take 1.225 kg / m³; gust factor G is taken as 1.0; drag coefficient C f Take 1.2; take the conductor diameter D as 0.016 m.

[0062] (2) An integral yields the aerodynamic expression for the wind load on a certain section of the conductor:

[0063] Specifically, for the damaged distribution pole B, the formula for calculating the wind load on the four conductor segments is as follows: L AB Lateral force on damaged distribution pole B caused by aerodynamic forces of the conductor segment:

[0064] L BC Lateral force on damaged distribution pole B caused by aerodynamic forces of the conductor segment:

[0065] L CD Lateral force on damaged distribution pole B caused by aerodynamic forces of the conductor segment:

[0066] L DE Lateral force B on the damaged distribution pole caused by the aerodynamic forces of the conductor segment:

[0067] In the formula, L The span of a single conductor is 50 m.

[0068] (3) By summing the values ​​of the four conductor segments, the total lateral force caused by the aerodynamic forces on the conductors due to the tornado is obtained as follows:

[0069] After solving the integral, we get:

[0070] The fourth step is to analyze the directional components of the wind load. The specific process is as follows: Based on the angle between the guide wire and the direction of the tornado's rotation α The aerodynamic force is decomposed into two components: tangential and radial. =0.4 In the formula, and These represent the loads on the distribution poles in the tangential and radial directions caused by the aerodynamic lateral force of the conductors during the tornado. This is equivalent to the angle between the conductor and the tangent of the tornado. The aerodynamic forces caused by the wind load on the conductor are calculated as follows: Figure 4 As shown.

[0071] Step 5: Taking the actual damaged distribution pole B as an example, explain how to superimpose the conductor load and the pole's own wind pressure under the action of a tornado, and calculate the total wind load response of the distribution pole: (1) The main distribution pole is a hollow reinforced concrete pole with diameters of 0.15m and 0.24m at the top and bottom of the pole, respectively, and the total height of the pole is [missing information]. h 1 is 7 m. The diameter of the rod changes at a rate of 7 m. Based on the aforementioned parameters related to tornado wind fields, supplement... r / r c Tornado boundary layer thickness at a normalized distance of 0.4 m m.

[0072] (2) Calculate the wind load on the conductor at the damaged pole according to the wind load calculation method of the conductor in the third and fourth steps. , .

[0073] (3) Integrating the wind load density of the pole along the pole height, the wind-induced bending moments of the pole along the windward and crosswind directions are respectively M jx = 13.24 kN·m and M jy = 9.75 kN·m, and the combined total bending moment is 16.42 kN·m. This value, as the basis for superposition with the conductor load component, reflects the contribution of the wind pressure on the pole body to the structural response.

[0074] (4) Superposition of wind load on conductor: The aerodynamic force generated by the conductor is multiplied by the lever arm at the conductor's height (6 m), which is converted into a bending moment and added to the wind-induced bending moment in the corresponding direction of the pole to obtain the total bending moment:

[0075] The final base bending moment is:

[0076] in, k The basic wind pressure amplification factor is set to 1.0.

[0077] (5) Determine the structural limit wind speed.

[0078] The bending bearing capacity of the power distribution pole structure was calculated using the material parameters of C30 concrete and eight 5mm diameter Q235 steel bars:

[0079] Among them, concrete reduction factor Take 1.0 as the standard value of axial compressive strength of concrete. It is 26.8 MPa. A The area of ​​the annular cross-section of the concrete. A s For the area of ​​the reinforcing steel, r 1. The outer diameter of the concrete pole is taken as 0.24 m. r 2. The inner diameter of the concrete pole is taken as 0.16m. The ratio of the area Ac of the concrete compression zone to the total cross-sectional area can be calculated using the following formula: ; It is the ratio of the cross-sectional area of ​​the tensile longitudinal reinforcement to the total cross-sectional area of ​​the longitudinal reinforcement. ,when When >2 / 3, The calculated bending capacity of the power distribution pole structure is 7.4 kN·m.

[0080] Furthermore, wind speeds at all 10m heights were measured. Calculated root bending moment Curve and root resistance By performing intersection interpolation, the critical point of failure wind speed is obtained: m / s, such as Figure 5 As shown.

[0081] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for calculating the wind load on power distribution conductors under the action of a tornado, characterized in that, Includes the following steps: A tornado wind field model was constructed, simplifying the wind field to the dominant tangential wind speed distribution; the center position of the conductor segment under the span configuration was extracted, and its radial spatial relationship with the tornado center was determined to determine the position of the conductor relative to the wind field. Establish wind load integral calculation models for each span of the conductor, and calculate the aerodynamic forces of the conductor under the action of tornado based on the established wind load integral calculation models. By decomposing the load direction and analyzing the structural stress, the aerodynamic force of the conductor is converted into the wind load of the distribution pole. The total wind load response of the distribution pole is obtained by superimposing the wind load transmitted by the conductor on the pole body.

2. The method for calculating wind load on power distribution conductors under tornado conditions according to claim 1, characterized in that, Constructing a tornado wind field model includes: A two-dimensional Rankine vortex model was used to establish the tornado wind speed distribution model. The variation of wind speed with height and the influence of radial wind speed components were ignored. Only the force characteristics of the conductor under tangential wind speed were considered. The wind speed model is as follows: In the formula: Radial position from the center of the tornado r Tangential wind speed at that location V m This is the maximum tangential wind speed of a tornado. r c This represents the radial distance corresponding to the point of maximum tangential wind speed.

3. The method for calculating wind load on power distribution conductors under tornado conditions according to claim 2, characterized in that, Determining its radial spatial relationship relative to the tornado center includes: By combining the relative position of the power line spans with the tornado wind field, the wind speed distribution, and the direction of wind load, the conductor span sections within the tornado's influence area are identified, and the vertical distance between the tornado center and the conductors is determined. d The point where the conductor experiences the strongest wind in the wind speed distribution. for: in, This is the horizontal distance from the starting point of the conductor to the point of maximum wind speed, used to define the starting point location of the wind load integration.

4. The method for calculating wind load on power distribution conductors under tornado conditions according to claim 3, characterized in that, The wind load integral calculation model for each span of the conductor includes: A distributed wind load calculation model is established. Based on aerodynamic theory, the formula for calculating the wind load per unit length of conductor is as follows: in, Where is air density, G is gust factor, and C is air density. f Where D is the drag coefficient and D is the conductor diameter. For wires x Wind speed at the location; The aerodynamic expressions for wind loads on conductors of each span are obtained by integration: in, L This refers to the span of a single conductor segment.

5. The method for calculating wind load on power distribution conductors under tornado conditions according to claim 4, characterized in that, The calculated aerodynamic forces acting on the tornado conductor include: Calculate the lateral force on the damaged distribution pole caused by the aerodynamic forces of all conductor segments; By summing the values ​​of all conductor segments, the total lateral force caused by the aerodynamic forces on the conductors due to the tornado is obtained as follows: 。 6. The method for calculating wind load on power distribution conductors under tornado conditions according to claim 5, characterized in that, Converting conductor aerodynamic forces into wind loads on distribution poles includes: Based on the angle between the guide wire and the direction of the tornado's rotation α The aerodynamic force is decomposed into two components: tangential and radial. In the formula, and These represent the loads on the distribution poles in the tangential and radial directions caused by the aerodynamic lateral force of the conductors during the tornado.

7. The method for calculating wind load on power distribution conductors under tornado conditions according to claim 1, characterized in that, The superposition of the wind load on the distribution pole transmitted by the conductor and the wind pressure on the pole body includes: The additional bending moment generated by the wind load on the conductor is linearly superimposed with the wind pressure bending moment of the pole body in two main directions to obtain the total base bending moment of the distribution pole under the action of the tornado wind field, and then the structural safety assessment or wind load inversion analysis is carried out.

8. A calculation system for wind load on power distribution conductors under tornado conditions, characterized in that, include: The tornado wind field model building module constructs a tornado wind field model, simplifying the wind field to focus on the dominant tangential wind speed distribution. Extract the center position of the conductor segment under the span configuration and determine its radial spatial relationship relative to the tornado center in order to determine the position of the conductor relative to the wind field. The conductor wind load integral model construction module establishes a wind load integral calculation model for each span of the conductor, and calculates the aerodynamic force of the conductor under the action of a tornado based on the established wind load integral calculation model. The wind load direction component analysis module converts the aerodynamic force of the conductor into the wind load of the distribution pole through load direction decomposition and structural stress analysis. The wind load assessment module superimposes the wind load transmitted by the conductors to the distribution pole with the wind pressure on the pole itself to calculate the total wind load response of the distribution pole.

9. The calculation system for wind load on power distribution conductors under tornado conditions according to claim 8, characterized in that, Constructing a tornado wind field model includes: A two-dimensional Rankine vortex model was used to establish the tornado wind speed distribution model. The variation of wind speed with height and the influence of radial wind speed components were ignored. Only the force characteristics of the conductor under tangential wind speed were considered. The wind speed model is as follows: In the formula: Radial position from the center of the tornado r Tangential wind speed at that location V m This is the maximum tangential wind speed of a tornado. r c This represents the radial distance corresponding to the point of maximum tangential wind speed.

10. A computer storage medium having a computer program stored thereon, characterized in that, When the computer executes the computer program, it implements the method for calculating the wind load on power distribution conductors under the action of a tornado, as described in any one of claims 1-7.

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