Tornado action under the distribution of conductor wind load calculation method, system and storage medium

Abstract

The application discloses a tornado-affected power distribution conductor wind load calculation method and system and a storage medium. The method comprises the following steps: constructing a tornado wind field model, simplifying the wind field into a main leading tangential wind speed distribution; extracting a conductor segment center position under a span configuration, and measuring a radial spatial relationship of the conductor segment center position relative to a tornado center; establishing a wind load integral calculation model of each span segment of the conductor, and calculating an aerodynamic load distribution of adjacent span conductors; converting the conductor aerodynamic force into an external load of a power distribution pole structure through load direction decomposition and structural stress analysis; and superimposing conductor transmission loads and pole body wind pressure, and calculating a total wind load response of the power distribution pole. The method realizes accurate modeling and distribution of the conductor aerodynamic force in the space and structure layers. The method is suitable for wind load analysis of a power distribution line under the action of tornadoes and other local strong winds, and provides fine input parameters for safety evaluation of a power distribution system structure.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of power system structure wind engineering, and relates to a calculation method and system for wind load of a distribution conductor under the action of a tornado and a storage medium. BACKGROUND

[0002] Tornadoes have typical characteristics such as small scale, strong burst, large wind speed, short duration and severe wind field change, and cause serious threats to linear infrastructures such as distribution conductors. Due to the complex structure of the tornado wind field and the large spatial gradient of the wind speed, it is difficult for a conventional observation system to obtain effective wind speed data in real time, which significantly increases the uncertainty in the calculation of the wind load and further affects the scientificity of the structural design and post-disaster evaluation. Post-disaster investigation shows that the distribution conductor, as a typical indicator of wind-induced damage, bears significant tangential and radial wind speed coupling effects under the action of the tornado wind field, and especially in the area close to the eye, the distribution conductor wind load distribution presents strong non-uniformity, far exceeding the load characteristics under the conventional static wind condition.

[0003] Existing calculation models generally ignore the aerodynamic differences of the conductor at different horizontal positions, and commonly use the average static pressure method to estimate the conductor load, which fails to reflect the spatial distribution characteristics. Meanwhile, the conductor wind load is transmitted to the distribution pole through the insulator, and has an impact on the additional wind load of the pole body structure, while the traditional analysis only focuses on the wind pressure of the pole body, and there is currently a lack of wind load calculation method that can systematically consider the transmission effect of the conductor wind load. Therefore, it is urgent to establish a calculation method that considers the structure of the tornado wind field, the relative position relationship between the conductor and the wind field and the distribution characteristics of the conductor wind load, so as to improve the accuracy and reliability of the wind load evaluation of the distribution structure under the tornado. SUMMARY

[0004] The application aims to provide a calculation method and system for wind load of a distribution conductor under the action of a tornado and a storage medium, which considers the structure of the tornado wind field, the relative position relationship between the conductor and the wind field and the distribution characteristics of the conductor wind load, and can improve the accuracy and reliability of the wind load evaluation of the distribution structure under the tornado.

[0005] The technical solution for achieving the object of the application is as follows:

[0006] A calculation method for wind load of a distribution conductor under the action of a tornado, comprising the following steps:

[0007] A tornado wind field model is constructed, and the wind field is simplified as a main leading tangential wind speed distribution; the center position of the conductor segment under the span configuration is extracted, and the radial spatial relationship thereof relative to the center of the tornado is determined to determine the relative position of the conductor relative to the wind field;

[0008] An integral calculation model for the wind load of each span segment of the conductor is established, and the aerodynamic force of the conductor under the action of the tornado is calculated according to the established integral calculation model for the wind load.

[0009] 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.

[0010] The total wind load response of the distribution pole is obtained by superimposing the wind load transmitted by the conductor on the pole body.

[0011] In the preferred technical solution, constructing the tornado wind field model includes:

[0012] 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 the radial wind speed component were ignored. Only the force characteristics of the conductor under tangential wind speed were considered. The wind speed model is as follows:

[0013]

[0014] 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.

[0015] In the preferred technical solution, determining its radial spatial relationship relative to the tornado center includes:

[0016] 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. Represented as:

[0017]

[0018] 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.

[0019] In the preferred technical solution, the wind load integral calculation model for each span of the conductor includes:

[0020] 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:

[0021]

[0022] in, Where is air density, G is gust factor, and C is air density. fis the wind resistance coefficient, affected by Reynolds number, which can be determined by table, D is the diameter of the conductor, is the conductor x wind speed at the location;

[0023] The aerodynamic force expression of the wind load on the conductor in each span section is obtained by integration:

[0024]

[0025] wherein, L is the single span of the conductor.

[0026] In the preferred technical solution, the calculated aerodynamic force of the conductor under the action of tornado includes:

[0027] The lateral force of the damaged distribution pole caused by the aerodynamic force of all the conductors is calculated.

[0028] The total lateral force of the damaged distribution caused by the aerodynamic force of the conductor under the action of tornado is obtained by summing all the conductors:

[0029] .

[0030] In the preferred technical solution, converting the aerodynamic force of the conductor into the wind load of the distribution pole includes:

[0031] According to the angle between the conductor and the rotating direction of the tornado α , the aerodynamic force is decomposed into tangential and radial components:

[0032]

[0033]

[0034]

[0035]

[0036] In the formula, and are the loads of the distribution pole in the tangential and radial directions of the tornado caused by the aerodynamic lateral force of the conductor.

[0037] In the preferred technical solution, superimposing the wind load of the conductor on the distribution pole and the wind pressure on the pole body includes:

[0038] Linearly superimpose the additional bending moment generated by the conductor wind load and the bending moment of the pole body wind pressure in two main directions respectively, to obtain the total base bending moment of the distribution pole under the action of the tornado wind field, and perform structural safety evaluation or wind load inversion analysis.

[0039] The application also discloses a calculation system of wind load of a distribution conductor under the action of a tornado.

[0040] A tornado wind field model construction module constructs a tornado wind field model, simplifies the wind field into a dominant tangential wind speed distribution, extracts the center position of the conductor segment under the span configuration, determines the radial spatial relationship of the conductor relative to the tornado center, and determines the relative position of the conductor to the wind field;

[0041] A conductor wind load integral model construction module establishes a wind load integral calculation model for each span segment of the conductor, and calculates the aerodynamic force of the conductor under the action of the tornado according to the established wind load integral calculation model;

[0042] A wind load direction component analysis module converts the conductor aerodynamic force into the wind load of the distribution pole through load direction decomposition and structural stress analysis;

[0043] A wind load evaluation module superimposes the wind load of the distribution pole transmitted by the conductor and the wind pressure received by the pole body to obtain the total wind load response of the distribution pole.

[0044] The application also discloses a computer storage medium, which stores a computer program, and the computer program is executed by a computer to realize the calculation method of the wind load of the distribution conductor under the action of the tornado.

[0045] Compared with the prior art, the application has the following advantages:

[0046] The calculation method considers the structure of the tornado wind field, the relative position relationship between the conductor and the wind field, and the distribution characteristics of the wind load of the conductor, realizes accurate modeling and distribution of the conductor aerodynamic force in the space and structural layers, and can improve the accuracy and reliability of the wind load evaluation of the distribution structure under the tornado. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 The application discloses a calculation method of the wind load of a distribution conductor under the action of a tornado.

[0048] Figure 2 The application discloses a calculation method of the wind load of a distribution conductor under the action of a tornado.

[0049] Figure 3 The application discloses a calculation method of the wind load of a distribution conductor under the action of a tornado.

[0050] Figure 4 The application discloses a calculation method of the wind load of a distribution conductor under the action of a tornado.

[0051] Figure 5 The application discloses a calculation method of the wind load of a distribution conductor under the action of a tornado. DETAILED DESCRIPTION

[0052] The principle of the present application is: according to the two-dimensional Rankine vortex model, the tornado wind speed distribution field is constructed, the relative radial position of the conductor and the tornado center is combined, the aerodynamic load distribution of the adjacent span conductor is calculated; by using the simply supported beam shear influence line principle, the conductor wind load is distributed to the distribution pole position, and is superposed with the wind pressure borne by the distribution pole body, so as to form the mapping relationship between the conductor wind load spatial distribution and the aerodynamic response of the distribution pole, and then the accurate calculation of the total wind load of the distribution line under the tornado wind field is realized.

[0053] Embodiments

[0054] As Figure 1 shown, a calculation method of wind load of distribution conductor under tornado action, comprising the following steps:

[0055] The tornado wind field model is constructed, and the wind field is simplified as the main leading tangential wind speed distribution; the center position of the conductor segment under the span configuration is extracted, the radial spatial relationship relative to the tornado center is determined, so as to determine the relative position of the conductor to the wind field;

[0056] The wind load integral calculation model of each span segment of the conductor is established, and the aerodynamic force of the conductor under the action of the tornado is calculated according to the established wind load integral calculation model;

[0057] Through load direction decomposition and structure stress analysis, the conductor aerodynamic force is converted into the wind load of the distribution pole;

[0058] The wind load of the distribution pole transmitted by the conductor is superposed with the wind pressure borne by the pole body, and the total wind load response of the distribution pole is obtained.

[0059] In a preferred embodiment, the tornado wind field model is constructed, comprising:

[0060] The two-dimensional Rankine vortex model is used to establish the tornado wind speed distribution model, the change of wind speed with height direction and the influence of radial wind speed component are ignored, and only the stress characteristics of the conductor under the action of tangential wind speed are considered, and the wind speed model is as follows:

[0061]

[0062] In the formula: is the tangential wind speed at the radial position of the tornado center r V m is the maximum tangential wind speed of the tornado, r c is the corresponding radial distance at the maximum tangential wind speed.

[0063] In a preferred embodiment, the radial spatial relationship relative to the tornado center is determined, comprising:

[0064] ​The wind field influence range of the conductor span section is identified in combination with the relative position of the power distribution line span and the tornado wind field, and the wind speed distribution and the wind load action direction, and the vertical distance of the tornado center relative to the conductor is determined d The point where the conductor is most strongly affected by the wind in the wind speed distribution is represented as:

[0065]

[0066] wherein, is the horizontal distance from the starting point of the conductor to the point of maximum wind speed, used to define the starting position of the wind load integration.

[0067] In a preferred embodiment, the wind load integration calculation model of each span section of the conductor includes:

[0068] The distributed wind load calculation model is established, and based on the aerodynamic force theory, the wind load calculation formula per unit length of the conductor is:

[0069]

[0070] wherein, is the air density, G is the gust factor, C f is the wind resistance coefficient, which is affected by the Reynolds number and can be determined by referring to the table, and D is the diameter of the conductor, is the wind speed at the position of the conductor x .

[0071] The aerodynamic force expression of the wind load of the conductor in each span section is obtained by integration:

[0072]

[0073] wherein, L is the single span of the conductor.

[0074] In a preferred embodiment, the calculation of the aerodynamic force of the conductor under the action of the tornado includes:

[0075] The lateral force of the damaged power distribution pole caused by the aerodynamic force of all the sections of the conductor is calculated.

[0076] The total lateral force of the damaged power distribution caused by the aerodynamic force of the conductor under the action of the tornado is obtained by summing all the sections of the conductor:

[0077] .

[0078] In a preferred embodiment, the conversion of the aerodynamic force of the conductor into the wind load of the power distribution pole includes:

[0079] According to the included angle between the conductor and the rotation direction of the tornado α , the aerodynamic force is decomposed into two components in the tangential and radial directions:

[0080]

[0081]

[0082]

[0083]

[0084] wherein, and are the tangential and radial load of the distribution pole caused by the aerodynamic force of the conductor respectively.

[0085] In a preferred embodiment, the wind load of the distribution pole transmitted by the conductor is superimposed with the wind pressure on the pole body, including:

[0086] The additional bending moment caused by the wind load of the conductor is linearly superimposed with the bending moment of the wind pressure on the pole body in two main directions respectively, to obtain the total base bending moment of the distribution pole under the action of the tornado wind field, for structural safety evaluation or wind load inversion analysis.

[0087] In another embodiment, a system for calculating the wind load of a distribution conductor under the action of a tornado, comprising:

[0088] A tornado wind field model construction module constructs a tornado wind field model, simplifies the wind field into a main tangential wind speed distribution, extracts the center position of the conductor segment under the span configuration, determines the radial spatial relationship thereof relative to the center of the tornado, to determine the position of the conductor relative to the wind field;

[0089] A conductor wind load integral model construction module establishes a wind load integral calculation model for each span segment of the conductor, and calculates the aerodynamic force of the conductor under the action of the tornado according to the established wind load integral calculation model;

[0090] A 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;

[0091] A wind load evaluation module superimposes the wind load of the distribution pole transmitted by the conductor with the wind pressure on the pole body, to obtain the total wind load response of the distribution pole.

[0092] The working process of the system for calculating the wind load of the distribution conductor under the action of the tornado will be described below with a specific example, including the following steps:

[0093] Step 1: Construct a tornado wind field model, the specific process is as follows:

[0094] In the modeling process according to the typical tornado rotating vortex characteristics, the tornado wind speed distribution model based on two-dimensional Rankine vortex model is constructed, ignoring the change of wind speed with height direction and the influence of radial wind speed component, only considering the conductor stress characteristics under the action of tangential wind speed; At the same time, the relative radial position of conductor and tornado center is determined to obtain its wind characteristics, and the wind speed model is as follows:

[0095]

[0096] In the formula: is the tangential wind speed at the radial position of r from the tornado center; V m is the maximum tangential wind speed of tornado; r c is the corresponding radial distance of the maximum tangential wind speed.

[0097] When the position of the conductor is less than r from the tornado center, c the tangential wind speed increases linearly with the radial distance; when it is greater than r c , the tangential wind speed decays inversely with the radial distance.

[0098] It should be noted that, as shown in Figure 2 , the value of V m can be determined according to the wind field intensity evaluated by disaster investigation and the maximum tangential wind speed interval corresponding to different grades of tornado, and the specific value of r c can be determined by the approximate moving path of tornado and the damage degree distribution.

[0099] Second step: determine the relative position of the conductor to the wind field. The specific process is as follows:

[0100] In the adjacent two distribution line spans, there are three distribution poles, as shown in Figure 3 , the letters are A, B and E. The middle distribution pole is damaged, and B is the damaged distribution pole. Combined with its relative position to the tornado wind field, wind speed distribution and wind load action direction, taking C point as the center, four conductor span sections in the influence range of tornado wind field are identified: L AB , L BC , L CD , L DE , the vertical distance of the tornado center relative to the conductor is determined d . The strongest point of the conductor in the wind speed distribution is defined as , which is represented as:

[0101]

[0102] wherein, is the horizontal distance from the starting point of the conductor to the maximum point of wind speed, used to define the starting point of the wind load integration.

[0103] Step 3: Establish the wind load integration model of the conductor. The specific process is as follows:

[0104] (1) Considering the non-uniformity of wind speed along the conductor direction, a distributed wind load calculation model is established. Based on the aerodynamic theory, the wind load calculation formula per unit length of the conductor is:

[0105]

[0106] wherein, is the air density; G is the gust factor; C f is the wind resistance coefficient, which is affected by the Reynolds number and can be determined by looking up the table; D is the diameter of the conductor; is the wind speed at the position of the conductor. x

[0107] (2) The aerodynamic force expression of a certain section of the conductor under the wind load is obtained by certain integration:

[0108]

[0109] Specifically, for the damaged distribution pole B, the wind load calculation formula of the four sections of the conductor is as follows:

[0110] L AB The lateral force of the damaged distribution pole B caused by the aerodynamic force of the first section of the conductor:

[0111]

[0112] L BC The lateral force of the damaged distribution pole B caused by the aerodynamic force of the second section of the conductor:

[0113]

[0114] L CD The lateral force of the damaged distribution pole B caused by the aerodynamic force of the third section of the conductor:

[0115]

[0116] L DE The lateral force of the damaged distribution pole B caused by the aerodynamic force of the fourth section of the conductor:

[0117] ​

[0118] where, L is the span of the single segment conductor.

[0119] (3) The total lateral force of the damaged distribution caused by the aerodynamic force of the tornado acting on the conductor is obtained by summing the four segments of the conductor:

[0120]

[0121] After integration, we get:

[0122]

[0123] Fourth step, analyze the direction component of wind load, the specific process is as follows:

[0124] According to the angle between the conductor and the direction of rotation of the tornado α , the aerodynamic force is decomposed into two components in the tangential and radial directions:

[0125]

[0126]

[0127]

[0128]

[0129] where, and are the loads of the distribution pole in the tangential and radial directions of the tornado caused by the aerodynamic lateral force of the conductor. is equivalent to the angle between the conductor and the tangent direction of the tornado.

[0130] Fifth step: 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.

[0131] The additional bending moment of the conductor wind load and the bending moment of the pole body wind pressure are linearly superimposed in two main directions respectively, and the total base bending moment of the distribution pole under the action of the tornado wind field is obtained, which is used for structural safety evaluation or wind load inversion analysis.

[0132] A possible embodiment, see the description of the actual EF2 tornado caused distribution line damage example below, not here.

[0133] The following is an example of an actual EF2 tornado caused distribution line damage:

[0134] First step: according to the damaged location of the distribution pole, the wind damage signs and trajectory characteristics obtained after the disaster investigation, combined with Figure 2The tornado wind field model and key parameters are confirmed according to the path shown. The specific process is as follows:

[0135] Considering the typical rotating vortex characteristics of tornadoes, a two-dimensional Rankine vortex model is used to construct a tangential wind speed distribution model. The Rankine vortex model divides the entire wind field into an inner core region and an external region: when , the tangential wind speed increases linearly; when , the tangential wind speed decays inversely. Its wind speed expression is:

[0136]

[0137] According to the investigation data, is the tangential wind speed at a radial position r =20 m from the tornado center; the large tangential wind speed corresponds to a radius r c =50 m, thus calculating r / r c =0.4. The height of the guide wire from the ground is 6 m. Establish the wind speed-structure mechanics correlation and select multiple discrete values of the maximum tangential wind speed m / s for calculation.

[0138] Second step: Determine the relative position of the guide wire to the wind field. The specific process is as follows:

[0139] As shown in Figure 3 , within the adjacent two distribution line spans, there are three distribution poles, represented by letters A, B, and E. The middle distribution pole is damaged, and B is the damaged distribution pole. Combining its relative position to the tornado wind field, wind speed distribution, and wind load action direction, taking point C as the center, identify the 4 guide wire span sections within the tornado wind field influence range: L AB , L BC , L CD , L DE Determine the vertical distance of the tornado center relative to the guide wire d = 20 m. Define the strongest wind point of the guide wire in the wind speed distribution , represented as:

[0140]

[0141] Among them, the horizontal distance from the starting point of the guide wire to the maximum wind point is:

[0142] .

[0143] Third step: Establish the guide wire wind load integral model. The specific process is as follows:

[0144] (1) Considering the non-uniformity of wind speed along the direction of the conductor, a distributed wind load calculation model is established. Based on the aerodynamic theory, the wind load calculation formula per unit length of the conductor is:

[0145]

[0146] Where, air density Take 1.225 kg / m³; gust factor G take 1.0; wind resistance coefficient C f Take 1.2; conductor diameter D take 0.016 m.

[0147] (2) A certain integral obtains the aerodynamic force expression of a certain section of conductor under wind load:

[0148]

[0149] Specifically, for the damaged distribution pole B, the wind load calculation formula of the four sections of conductors is as follows:

[0150] L AB The transverse force of the damaged distribution pole B caused by the aerodynamic force of the first section of conductor:

[0151]

[0152] L BC The transverse force of the damaged distribution pole B caused by the aerodynamic force of the second section of conductor:

[0153]

[0154] L CD The transverse force of the damaged distribution pole B caused by the aerodynamic force of the third section of conductor:

[0155]

[0156] L DE The transverse force of the damaged distribution pole B caused by the aerodynamic force of the fourth section of conductor:

[0157]

[0158] Where, L The span of the single section of conductor is 50 m.

[0159] (3) The total transverse force of the damaged distribution caused by the aerodynamic force of the conductor under the action of tornado is obtained by summing the four sections of conductors:

[0160]

[0161] After integral solution, we can get:

[0162]

[0163] Fourth step, analysis of wind load direction component, the specific process as follows:

[0164] According to the angle between the conductor and the tornado rotation direction α , the aerodynamic force is decomposed into tangential and radial direction components:

[0165]

[0166]

[0167]

[0168] =0.4

[0169] In the formula, and are the load of the distribution pole in the tangential and radial directions of the tornado caused by the aerodynamic transverse force of the conductor. Equivalent to the angle between the conductor and the tangent direction of the tornado. The aerodynamic force caused by the wind load of the conductor is shown in Figure 4 .

[0170] Step 5: Take B actual damaged distribution pole as an example, explain how to superimpose the conductor load and the pole self wind pressure under the action of tornado, calculate the total wind load response of distribution pole:

[0171] (1) The main distribution pole is a reinforced concrete hollow pole, the diameters of the top and bottom of the pole body are 0.15 m and 0.24 m respectively, and the total height of the pole body is h 1 7 m. The diameter change rate of the pole body is According to the above tornado wind field related parameters, the boundary layer thickness of the tornado at the standardized distance of r / r c =0.4 m is supplemented m.

[0172] (2) According to the third step and the fourth step, the wind load of the conductor at the damaged pole is calculated , .

[0173] (3) The pole body wind load density is integrated along the pole height direction, and the wind induced bending moment of the pole body along the wind direction and the transverse direction is respectively M jx = 13.24 kN·m and M jy = 9.75 kN·m, the total bending moment is 16.42 kN·m. This value is superimposed with the conductor load component, representing the contribution of the wind pressure on the structure.

[0174] (4) Conductor wind load superposition: the aerodynamic force generated by the conductor is multiplied by the force arm at the conductor action height (6 m) to convert it into a bending moment, and is added to the wind-induced bending moment in the corresponding direction of the pole body to obtain the total bending moment:

[0175]

[0176]

[0177] The final base bending moment is:

[0178] wherein, k is the basic wind pressure amplification coefficient, taken as 1.0.

[0179] (5) Determine the ultimate wind speed of the structure.

[0180] The bending resistance of the distribution pole structure is calculated by the material parameters of C30 concrete and 8 Q235 steel bars with a diameter of 5 mm:

[0181]

[0182] wherein, the concrete reduction coefficient is taken as 1.0, the standard value of the axial compressive strength of concrete is 26.8 MPa, A is the concrete ring cross-sectional area, A s is the steel area, r 1 is the outer diameter of the concrete pole taken as 0.24 m, r 2 is the inner diameter of the concrete pole taken as 0.16 m, is the ratio of the concrete compression zone area Ac to the full cross-sectional area, which can be calculated by the following formula: ; is the ratio of the tensile longitudinal steel cross-sectional area to the total longitudinal steel cross-sectional area, when >2 / 3, . The bending resistance of the distribution pole structure is calculated to be 7.4 kN·m.

[0183] Further, all wind speeds at a height of 10 m are traversed to calculate the root bending moment , and the root resistance is interpolated to obtain the critical point of the failure wind speed: m / s, as shown in Figure 5 .

[0184] The above embodiments are preferred embodiments of the present application, but the embodiments of the present application are not limited to the above embodiments, and any changes, modifications, substitutions, combinations, simplifications, etc. made without departing from the spirit and principles of the present application are equivalent replacement modes and are included in the protection scope of the present application.

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: Construct a tornado wind field model to simplify the wind field as the dominant tangential wind speed distribution; Extracting the center position of the conductor segment under the span configuration and determining its radial spatial relationship relative to the tornado center to determine the conductor's position relative to the wind field; the construction of the tornado wind field model includes: A two-dimensional Rankine vortex model is used to establish the tornado wind speed distribution model, 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. The determination of 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. A wind load integral calculation model for each span of the conductor is established, and the aerodynamic forces acting on the conductor under tornado effect are calculated based on the established wind load integral calculation model; the establishment of 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 For a single conductor span; the calculated aerodynamic forces on the conductor caused by the tornado 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: 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, 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.

3. 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.

4. A calculation system for wind load on power distribution conductors under tornado action, used to implement the calculation method for wind load on power distribution conductors under tornado action as described in claim 1, 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.

5. 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 1-3.

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