Fire condition-based power transmission conductor fracture risk early warning method and device, terminal equipment and storage medium

Abstract

The application discloses a power transmission conductor fracture risk early warning method and device under mountain fire conditions, terminal equipment and a storage medium, based on the convection heat transfer model between the power transmission conductor and the air, the heat conduction model between the aluminum wire and the steel strand and the surface temperature of the power transmission conductor, the temperature of each aluminum wire and steel strand in the inner and outer layers of the power transmission conductor is simulated and calculated; according to the temperature of each aluminum wire and steel strand and the preset breaking force of each aluminum wire and steel strand when the mountain fire does not occur, the breaking force corresponding to each aluminum wire and steel strand in the current mountain fire area is obtained, based on the total number of aluminum wires and steel strands, the breaking force of the aluminum wire and the steel strand, and the structure parameters and thermal expansion performance parameters of the power transmission conductor, the third breaking force corresponding to the power transmission conductor in the current mountain fire area is comprehensively evaluated, and the heat exchange process between the conductor and the surrounding environment under the simulation of the mountain fire conditions is realized, thereby realizing the accurate fracture risk early warning.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power transmission conductor fracture early warning, and particularly relates to a power transmission conductor fracture risk early warning method and device under a mountain fire condition, a terminal device and a storage medium. BACKGROUND

[0002] Mountain fire refers to a fire phenomenon caused by factors such as climate and terrain in a natural environment. When mountain fire spreads to the vicinity of a power transmission line, high-temperature flames and smoke will have a direct thermal effect on the power transmission conductor, causing the temperature of the conductor to rise, the mechanical properties to decrease, and in extreme cases, the conductor may break, causing power interruption and property loss. Then, by calculating and determining the tensile breaking force of the power transmission conductor in the mountain fire area, the fracture risk of the power transmission conductor can be early warned, and measures can be taken early to avoid or reduce the impact of mountain fire on the power transmission line.

[0003] However, the traditional tensile breaking force calculation method does not consider that the heat exchange process between the power transmission conductor and the surrounding environment under the mountain fire condition will cause different temperatures between the inner and outer layers of the power transmission conductor, but simply assumes that the temperature and damage of the inner and outer layers of the conductor are uniform after the mountain fire occurs, which will cause a large deviation between the calculation result and the actual situation, cannot accurately evaluate the tensile breaking force of the power transmission conductor under the mountain fire condition, and results in low accuracy of the fracture risk early warning. SUMMARY

[0004] The present application provides a power transmission conductor fracture risk early warning method and device under a mountain fire condition, a terminal device and a storage medium, which considers the convective heat exchange between the conductor and the air and the heat conduction between the aluminum wire and the steel strand, so as to simulate the heat exchange process between the conductor and the surrounding environment under the mountain fire condition, accurately evaluate the tensile breaking force of the power transmission conductor under the mountain fire condition, and improve the accuracy of the fracture risk early warning.

[0005] An embodiment of the present application provides a power transmission conductor fracture risk early warning method under a mountain fire condition, comprising:

[0006] obtaining the surface temperature of a power transmission conductor in a current mountain fire area; wherein the power transmission conductor comprises a plurality of aluminum wires and a plurality of steel strands;

[0007] generating the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand based on a convective heat exchange model between the power transmission conductor and the air, a heat conduction model between the aluminum wire and the steel strand, and a simulation calculation of heat transfer of the surface temperature;

[0008] According to the temperature simulation result of each aluminum wire and the first preset breaking force of each aluminum wire when no forest fire occurs, a first breaking force corresponding to each aluminum wire in the current forest fire area is generated; according to the temperature simulation result of each steel strand and the second preset breaking force of each steel strand when no forest fire occurs, a second breaking force corresponding to each steel strand in the current forest fire area is generated;

[0009] According to the total number of aluminum wires, the total number of steel strands, the first breaking force corresponding to each aluminum wire, the second breaking force corresponding to each steel strand, the structural parameters of the power transmission conductor and the thermal expansion performance parameters of the power transmission conductor, a third breaking force corresponding to the power transmission conductor in the current forest fire area is generated;

[0010] When it is determined that the third breaking force is less than the preset breaking force threshold corresponding to the power transmission conductor, early warning information for indicating that the power transmission conductor has a risk of fracture is generated.

[0011] Preferably, the power transmission conductor comprises a plurality of layers of aluminum wire strands and a plurality of layers of steel cores; the surface temperature is the temperature corresponding to the outermost layer of aluminum wire strands of the power transmission conductor; each layer of aluminum wire strands comprises a plurality of aluminum wires, and each layer of steel cores comprises a plurality of steel strands;

[0012] The simulation calculation of heat transfer based on the convection heat transfer model between the power transmission conductor and the air, the heat conduction model between the aluminum wire and the steel strand and the surface temperature generates the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand, comprising:

[0013] According to the total number of layers of aluminum wire strands, the number of aluminum wires of each layer of aluminum wire strands, the total number of layers of steel cores and the number of steel strands of each layer of steel cores, a simulation model corresponding to the power transmission conductor is generated by simulating modeling of the power transmission conductor;

[0014] According to the convection heat transfer coefficient, the surface temperature of the power transmission conductor and the air temperature, a convection heat transfer model between the power transmission conductor and the air is constructed;

[0015] According to the thermal conductivity coefficient of the aluminum wire, the thermal conductivity coefficient of the steel core and Fourier's law, a heat conduction model between the aluminum wire and the steel strand is constructed;

[0016] After the surface temperature is taken as the boundary temperature of the simulation model, the simulation calculation of heat transfer of the simulation model, the convection heat transfer model and the heat conduction model is performed, and the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand are output.

[0017] Preferably, the simulation calculation of heat transfer of the simulation model, the convection heat transfer model and the heat conduction model outputs the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand, comprising:

[0018] The temperature generation operation is repeatedly performed until the current iteration number is the same as the preset iteration number, the highest temperature of each aluminum wire in all simulation calculation operations is taken as the corresponding temperature simulation result of each aluminum wire, and the highest temperature of each steel strand in all simulation calculation operations is taken as the corresponding temperature simulation result of each steel strand:

[0019] The current temperature of each aluminum wire and the current temperature of each steel strand are obtained.

[0020] When the current iteration number is less than the preset iteration number, the simulation calculation operation of heat transfer of the simulation model, the convective heat transfer model and the heat conduction model is performed according to the current temperature of each aluminum wire and the current temperature of each steel strand, and the temperature of each aluminum wire in the current simulation calculation operation and the temperature of each steel strand in the current simulation calculation operation are output. Initially, the current temperature of each aluminum wire and the current temperature of each steel strand are generated according to the surface temperature of the power transmission conductor and the Fourier law.

[0021] The temperature of each aluminum wire in the current simulation calculation operation is taken as the current temperature of each aluminum wire in the next execution of the temperature generation operation, and the temperature of each steel strand in the current simulation calculation operation is taken as the current temperature of each steel strand in the next execution of the temperature generation operation.

[0022] Preferably, the first breaking force corresponding to each aluminum wire in the current mountain fire area is generated according to the temperature simulation result of each aluminum wire and the first preset breaking force of each aluminum wire when no mountain fire occurs, and the first breaking force corresponding to each aluminum wire in the current mountain fire area is calculated according to the following formula:

[0023] For each aluminum wire, the first breaking force corresponding to the aluminum wire in the current mountain fire area is calculated according to the following formula:

[0024]

[0025] Wherein, F2 is the first breaking force corresponding to the aluminum wire in the current mountain fire area, T L is the temperature simulation result of the aluminum wire, and F1 is the first preset breaking force of the aluminum wire when no mountain fire occurs.

[0026] Preferably, the second breaking force corresponding to each steel strand in the current mountain fire area is generated according to the temperature simulation result of each steel strand and the second preset breaking force of each steel strand when no mountain fire occurs, and the second breaking force corresponding to each steel strand in the current mountain fire area is calculated according to the following formula:

[0027] For each steel strand, the second breaking force corresponding to the steel strand in the current mountain fire area is calculated according to the following formula:

[0028]

[0029] F4 is a second breaking force of the steel strand corresponding to the current mountain fire area, T G F3 is a second preset breaking force of the steel strand when no mountain fire occurs.

[0030] Preferably, the structural parameters of the power transmission conductor include structural parameters of the aluminum wire and structural parameters of the steel strand; and the thermal expansion performance parameters of the power transmission conductor include thermal expansion performance parameters of the aluminum wire and thermal expansion performance parameters of the steel strand.

[0031] The third breaking force of the power transmission conductor corresponding to the current mountain fire area is generated according to the total number of aluminum wires, the total number of steel strands, the first breaking force corresponding to each aluminum wire, the second breaking force corresponding to each steel strand, the structural parameters of the power transmission conductor, and the thermal expansion performance parameters of the power transmission conductor.

[0032] The first comprehensive breaking force of each layer of aluminum wire strands is generated according to the number of aluminum wires of each layer of aluminum wire strands, the structural parameters of the aluminum wire, the thermal expansion performance parameters of the aluminum wire, and the first breaking force corresponding to each aluminum wire in each layer of aluminum wire strands.

[0033] The second comprehensive breaking force of each layer of steel cores is generated according to the number of steel strands of each layer of steel cores, the structural parameters of the steel strand, the thermal expansion performance parameters of the steel strand, and the second breaking force corresponding to each steel strand in each layer of steel cores.

[0034] The third breaking force of the power transmission conductor corresponding to the current mountain fire area is generated according to the first comprehensive breaking force of each layer of aluminum wire strands, the first preset breaking force coefficient corresponding to the aluminum wire strand, the second comprehensive breaking force of each layer of steel cores, and the second preset breaking force coefficient corresponding to the steel core.

[0035] Preferably, the structural parameters of the aluminum wire include the number of segments of the aluminum wire corresponding to the current mountain fire area, the elastic modulus of the aluminum wire, the cross-sectional area of the aluminum wire, and the length of the aluminum wire corresponding to the current mountain fire area; and the thermal expansion performance parameters of the aluminum wire include the linear thermal expansion coefficient of the aluminum wire and the average temperature of each segment length of the aluminum wire.

[0036] The first comprehensive breaking force of each layer of aluminum wire strands is generated according to the number of aluminum wires of each layer of aluminum wire strands, the structural parameters of the aluminum wire, the thermal expansion performance parameters of the aluminum wire, and the first breaking force corresponding to each aluminum wire in each layer of aluminum wire strands.

[0037] The area temperature corresponding to the current mountain fire area is obtained.

[0038] For each aluminum wire, the length change amount of the aluminum wire corresponding to the temperature rise is generated according to the area temperature, the linear thermal expansion coefficient of the aluminum wire, the number of segments of the aluminum wire corresponding to the current mountain fire area, and the average temperature of each segment length of the aluminum wire.

[0039] For each layer of aluminum wire strand, according to the length change amount corresponding to each aluminum wire when the temperature rises, the elastic modulus of each aluminum wire, the cross-sectional area of each aluminum wire, the length corresponding to the aluminum wire in the current wildfire area and the number of aluminum wires of the aluminum wire strand, the external tension corresponding to the aluminum wire strand when the temperature rises is generated;

[0040] For each layer of aluminum wire strand, according to the external tension corresponding to the aluminum wire strand when the temperature rises and the first breaking force corresponding to each aluminum wire in the aluminum wire strand, the first comprehensive breaking force of the aluminum wire strand is generated.

[0041] On the basis of the method embodiments described above, the application correspondingly provides device embodiments.

[0042] An embodiment of the application provides a power transmission conductor fracture risk early warning device based on a wildfire condition, comprising: a conductor surface temperature acquisition module, a temperature simulation result generation module, a first calculation module, a second calculation module and an early warning module;

[0043] The conductor surface temperature acquisition module is used to acquire the surface temperature of a power transmission conductor in a current wildfire area; wherein the power transmission conductor comprises a plurality of aluminum wires and a plurality of steel strands;

[0044] The temperature simulation result generation module is used to perform simulation calculation of heat transfer based on a convection heat transfer model between the power transmission conductor and air, a heat conduction model between the aluminum wires and the steel strands and the surface temperature, to generate the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand;

[0045] The first calculation module is used to generate the first breaking force corresponding to each aluminum wire in the current wildfire area according to the temperature simulation result of each aluminum wire and the first preset breaking force of each aluminum wire when no wildfire occurs, and generate the second breaking force corresponding to each steel strand in the current wildfire area according to the temperature simulation result of each steel strand and the second preset breaking force of each steel strand when no wildfire occurs;

[0046] The second calculation module is used to generate the third breaking force corresponding to the power transmission conductor in the current wildfire area according to the total number of aluminum wires, the total number of steel strands, the first breaking force corresponding to each aluminum wire, the second breaking force corresponding to each steel strand, the structural parameters of the power transmission conductor and the thermal expansion performance parameters of the power transmission conductor;

[0047] The early warning module is used to generate early warning information for indicating that the power transmission conductor has a fracture risk when it is determined that the third breaking force is less than a preset breaking force threshold corresponding to the power transmission conductor.

[0048] On the basis of the method embodiments described above, the application correspondingly provides terminal device embodiments.

[0049] Another embodiment of the present application provides a terminal device, comprising a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor implements the method for early warning of the fracture risk of a power transmission conductor under a forest fire condition according to any one of the above embodiments of the present application when executing the computer program.

[0050] Based on the above-mentioned method embodiments, the present application correspondingly provides storage medium embodiments.

[0051] Another embodiment of the present application provides a storage medium, wherein the computer readable storage medium comprises a stored computer program, wherein the computer program controls a device where the computer readable storage medium is located to execute the method for early warning of the fracture risk of a power transmission conductor under a forest fire condition according to any one of the above embodiments of the present application when the computer program is running.

[0052] By implementing the present application, the following beneficial effects are achieved:

[0053] The embodiments of the present application provide a method and device for early warning of the fracture risk of a power transmission conductor under a forest fire condition, a terminal device, and a storage medium. First, the surface temperature of a power transmission conductor in a current forest fire area is obtained. Then, based on the surface temperature, a heat convection model between the power transmission conductor and air, and a heat conduction model between aluminum wires and steel strands, simulation calculation is performed to accurately evaluate the temperature of each aluminum wire and steel strand in the inner and outer layers of the power transmission conductor. Further, according to the temperature simulation results of each aluminum wire and steel strand, in combination with the preset breaking force of each aluminum wire and steel strand when no forest fire occurs, the present application can further obtain the breaking force of each aluminum wire and steel strand corresponding to the current forest fire area. Finally, based on the total number of aluminum wires, the total number of steel strands, the breaking force of each aluminum wire and steel strand, the structural parameters of the power transmission conductor, and the thermal expansion performance parameters, the third breaking force of the power transmission conductor corresponding to the current forest fire area is comprehensively evaluated. The present application also considers the mechanical properties and structural characteristics of the whole conductor, so that the evaluation result is more comprehensive and reliable. Compared with the prior art, the present application considers the heat convection between the conductor and air and the heat conduction between the aluminum wires and steel strands, so that the heat exchange process between the conductor and the surrounding environment under the forest fire condition can be simulated. Therefore, the actual temperature of each aluminum wire and each steel strand can be more accurately calculated, i.e., the actual temperature of different materials in the inner and outer layers of the power transmission conductor can be obtained. Moreover, the mechanical properties and structural characteristics of the whole conductor are also considered, so that the present application can accurately evaluate the breaking force of the power transmission conductor under the forest fire condition, and the accuracy of the fracture risk early warning is improved. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1is a flowchart of a power transmission conductor fracture risk early warning method under a mountain fire condition according to an embodiment of the present application.

[0055] Figure 2 is a schematic diagram of internal and external layers of a power transmission conductor according to an embodiment of the present application.

[0056] Figure 3 is a flowchart of minimum tensile strength calculation and fracture early warning of a conductor under a mountain fire condition according to another embodiment of the present application.

[0057] Figure 4 is a structural diagram of a power transmission conductor fracture risk early warning device under a mountain fire condition according to an embodiment of the present application. DETAILED DESCRIPTION

[0058] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0059] As shown in Figure 1 is a flowchart of a power transmission conductor fracture risk early warning method under a mountain fire condition according to an embodiment of the present application. The power transmission conductor fracture risk early warning method under a mountain fire condition comprises the following steps.

[0060] Step S1: Obtain the surface temperature of a power transmission conductor in a current mountain fire area. The power transmission conductor comprises a plurality of aluminum wires and a plurality of steel strands.

[0061] Step S2: Based on a convection heat transfer model between the power transmission conductor and air, a heat conduction model between the aluminum wires and the steel strands, and a simulation calculation of heat transfer of the surface temperature, generate a temperature simulation result of each aluminum wire and a temperature simulation result of each steel strand.

[0062] Step S3: According to the temperature simulation result of each aluminum wire and a first preset tensile strength of each aluminum wire when no mountain fire occurs, generate a first tensile strength of each aluminum wire corresponding to the current mountain fire area. According to the temperature simulation result of each steel strand and a second preset tensile strength of each steel strand when no mountain fire occurs, generate a second tensile strength of each steel strand corresponding to the current mountain fire area.

[0063] Step S4: According to the total number of aluminum wires, the total number of steel wires, the first breaking force corresponding to each aluminum wire, the second breaking force corresponding to each steel wire, the structural parameters of the power transmission conductor and the thermal expansion performance parameters of the power transmission conductor, the third breaking force of the power transmission conductor in the current mountain fire area is generated.

[0064] Step S5: When the third breaking force is less than the preset breaking force threshold corresponding to the power transmission conductor, the early warning information for indicating the risk of fracture of the power transmission conductor is generated.

[0065] For step S1, in a preferred embodiment, after the mountain fire occurs near the power transmission line, the surface temperature of the power transmission conductor in the mountain fire area, i.e. the temperature of the outermost aluminum strand, can be obtained by infrared image temperature recognition technology.

[0066] Illustratively, the power transmission conductor comprises a plurality of layers of aluminum strands and a plurality of layers of steel cores; as Figure 2 The power transmission conductor of the present application is a steel-cored aluminum strand, and the inner layer is wound by a plurality of layers of steel cores, and the outer layer is wound by a plurality of layers of aluminum strands. Then, each layer of aluminum strand contains a plurality of aluminum wires, and each layer of steel core contains a plurality of steel strands.

[0067] Under the condition of mountain fire, the power transmission conductor will be affected by thermal radiation and thermal convection, and its surface temperature will rise. Since the thermal conductivity of aluminum is relatively good, the outermost aluminum strand will first and significantly reflect this temperature change. Therefore, by measuring the temperature of the outermost aluminum strand, the current heating condition of the conductor can be directly obtained.

[0068] Specifically, first, the location of the fire point can be determined, and the infrared radiation signal can be converted into a visible image by infrared thermal imaging technology. In the image, objects of different temperatures will show different brightness or color. Generally, the higher the temperature, the higher the brightness displayed in the image.

[0069] The processing circuit inside the thermal imager will calculate the temperature of the object corresponding to each pixel point in the image according to the received electrical signal and the pre-set algorithm. The calculated temperature information is displayed on the display screen of the thermal imager together with the optical image. Then, the temperature distribution of the outermost aluminum strand near the fire point can be directly observed.

[0070] The temperature rise of the aluminum strand will directly affect its mechanical properties and thermal expansion properties. By measuring the temperature of the outermost aluminum strand, the degree of influence of the mountain fire on the material properties of the conductor can be further evaluated, thereby providing key data for subsequent risk assessment.

[0071] For step S2, based on the measured surface temperature, the heat transfer simulation calculation can be further combined with the convection heat transfer model between the power transmission conductor and the air and the heat conduction model between the aluminum wire and the steel strand, so that the temperature change of the conductor inside (such as the steel core) can be accurately predicted, and the risk of conductor fracture can be more accurately evaluated.

[0072] In a preferred embodiment, the heat transfer simulation calculation based on the convection heat transfer model between the power transmission conductor and the air, the heat conduction model between the aluminum wire and the steel strand, and the surface temperature generates the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand, including:

[0073] According to the total number of aluminum wire strands, the number of aluminum wires in each layer of aluminum wire strands, the total number of steel cores, and the number of steel strands in each layer of steel cores, the power transmission conductor is simulated to generate a simulation model corresponding to the power transmission conductor;

[0074] According to the convection heat transfer coefficient, the surface temperature of the power transmission conductor, and the air temperature, a convection heat transfer model between the power transmission conductor and the air is constructed;

[0075] According to the thermal conductivity of the aluminum wire, the thermal conductivity of the steel core, and the Fourier law, a heat conduction model between the aluminum wire and the steel strand is constructed;

[0076] After the surface temperature is taken as the boundary temperature of the simulation model, the simulation calculation of heat transfer is performed on the simulation model, the convection heat transfer model, and the heat conduction model, and the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand are output.

[0077] Specifically, the modeling of the steel core aluminum stranded conductor is performed according to the number of aluminum strands, the number of aluminum wires in each layer, the number of steel cores, and the number of steel strands in each layer, and the boundary condition is set according to the temperature of the outermost layer of the aluminum strand, and when the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand are output, the specific process includes:

[0078] Repeat the following temperature generation operation until the current iteration number is the same as the preset iteration number, take the highest temperature of each aluminum wire in all simulation calculation operations as the corresponding temperature simulation result of each aluminum wire, and take the highest temperature of each steel strand in all simulation calculation operations as the corresponding temperature simulation result of each steel strand:

[0079] Obtain the current temperature of each aluminum wire and the current temperature of each steel strand;

[0080] When the current iteration number is less than the preset iteration number, the heat transfer simulation calculation operation is performed on the simulation model, the convection heat transfer model and the heat conduction model according to the current temperature of each aluminum wire and the current temperature of each steel strand, and the temperature of each aluminum wire in the current simulation calculation operation and the temperature of each steel strand in the current simulation calculation operation are output; wherein initially, the current temperature of each aluminum wire and the current temperature of each steel strand are generated according to the surface temperature of the power transmission conductor and the Fourier law;

[0081] The temperature of each aluminum wire in the current simulation calculation operation is taken as the current temperature of each aluminum wire when the temperature generation operation is performed next time, and the temperature of each steel strand in the current simulation calculation operation is taken as the current temperature of each steel strand when the temperature generation operation is performed next time.

[0082] It can be understood that the present application first constructs a convection heat transfer model between the power transmission conductor and the air, and a heat conduction model between the aluminum wire and the steel strand, and the two models respectively describe the heat exchange between the conductor and the external environment and the heat conduction process between different materials in the conductor.

[0083] Then, the temperature generation operation is repeatedly performed, and initially, the initial temperature of each aluminum wire and steel strand can be generated according to the surface temperature (i.e. the temperature of the outermost aluminum strand) of the power transmission conductor and the Fourier law.

[0084] Through the iterative way, the heat transfer simulation calculation is continuously performed according to the current temperature. In each iteration, the updated temperature of each aluminum wire and steel strand is calculated according to the simulation model, the convection heat transfer model and the heat conduction model. The iteration process will continue until the preset iteration number is reached. In each iteration, the temperature of each aluminum wire and steel strand is recorded to ensure that the temperature change rule of each aluminum wire and steel strand is captured.

[0085] Finally, after the iteration ends, the highest temperature of each aluminum wire and steel strand in each simulation calculation operation is taken as the temperature simulation result of each aluminum wire and steel strand, so as to accurately reflect the temperature distribution of different materials in the power transmission conductor under the mountain fire condition.

[0086] In a preferred embodiment, the temperature changes of the steel core and the aluminum strands are interrelated due to the presence of heat conduction, which transfers heat from the area with higher temperature (such as the outermost aluminum strand) to the area with lower temperature (the inner part of the aluminum wire and the steel core). In the simulation calculation, the temperature boundary conditions and related material parameters, such as the thermal conductivity of the steel core and the aluminum strand, constant-pressure heat capacity and other parameters, which are all temperature-dependent, can be set. The heat conduction of solid heat transfer and the convective heat transfer of solid-fluid heat transfer need to be calculated by iteration to obtain the temperature of the wire, and the simulation results show the temperature changes of the aluminum strand and the steel core at each time step. The maximum value can be found by the temperature change curve. Assuming that the time step is Δt, at time sequence t1, t2…, tn, (ti+1=ti+Δt), the temperature corresponding to the outermost aluminum strand at each time sequence is Touter-Aluminum(t1),…Touter-Aluminum(tn). By sorting and plotting the temperature change law according to the time sequence, the highest temperature corresponding to the maximum point of the temperature can be obtained.

[0087] where the heat transfer between the steel core and the aluminum strand is through heat conduction, and the basic law of heat conduction is Fourier's law, which can be expressed as:

[0088]

[0089] where the heat flux density J T is the heat transfer rate in the x direction per unit area perpendicular to the transmission direction. It is proportional to the temperature gradient dT / dx in this direction. The proportionality constant k is a transport property called thermal conductivity (also called thermal conductivity coefficient), with a unit of W·m-1·K-1, which can also be expressed as:

[0090]

[0091] The convective heat transfer between the wire and the air is considered. When the wire is in the air, heat will be transferred to the surrounding air through convective heat transfer, and this part of heat loss will affect the temperature distribution inside the wire. When performing overall temperature calculation, the influence of convective heat transfer needs to be considered. The specific convective heat transfer formula is as follows:

[0092] Q=h*A*(T w -T f );

[0093] where Q is the convective heat transfer between the power transmission wire and the air, h is the convective heat transfer coefficient, A is the heat transfer area, T w is the wall temperature, i.e. the surface temperature of the power transmission wire of the present application, and T f is the fluid (air) temperature.

[0094] Through continuously iterating the calculation process of the solid heat transfer and the solid-fluid heat transfer, and considering the mutual influence of the heat conduction and the convective heat transfer, finally the temperature of each aluminum wire and each steel strand can be obtained, so that the temperature variation law of each aluminum wire and the steel core with time during the mountain fire occurrence process is counted based on the calculation result, and the maximum temperature of each aluminum wire and each steel strand is extracted as the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand.

[0095] Then, through continuously iterating the calculation process of the solid heat transfer and the solid-fluid heat transfer, and considering the mutual influence of the heat conduction and the convective heat transfer, finally the temperature simulation result of each aluminum wire and each steel strand can be obtained, so that the temperature variation law of each aluminum wire and the steel core in the mountain fire process can be captured, including the temperature rising, peak value appearing and temperature falling stages, thereby the influence of the mountain fire on the temperature distribution of the power transmission conductor and the influence of the temperature variation on the mechanical property and fracture risk of the conductor can be more accurately analyzed.

[0096] For step S3, the maximum temperature of each aluminum wire and the steel core counted based on the simulation result can be further used to evaluate the tensile strength of each aluminum wire and the steel core under the mountain fire condition by considering the influence of the mountain fire on the mechanical property of the power transmission conductor material, especially the influence of the temperature on the tensile strength.

[0097] In a preferred embodiment, the first tensile strength of each aluminum wire corresponding to the current mountain fire area is generated according to the temperature simulation result of each aluminum wire and the first preset tensile strength of each aluminum wire when the mountain fire does not occur, which includes:

[0098] For each aluminum wire, the first tensile strength of the aluminum wire corresponding to the current mountain fire area is calculated according to the following formula:

[0099]

[0100] Wherein, F2 is the first tensile strength of the aluminum wire corresponding to the current mountain fire area, T L is the temperature simulation result of the aluminum wire, and F1 is the first preset tensile strength of the aluminum wire when the mountain fire does not occur.

[0101] In a preferred embodiment, the second tensile strength of each steel strand corresponding to the current mountain fire area is generated according to the temperature simulation result of each steel strand and the second preset tensile strength of each steel strand when the mountain fire does not occur, which includes:

[0102] For each steel strand, the second tensile strength of the steel strand corresponding to the current mountain fire area is calculated according to the following formula:

[0103]

[0104] F4 is the second breaking force of the steel strand corresponding to the current forest fire area, T G F3 is the second preset breaking force of the steel strand when no forest fire occurs.

[0105] Illustratively, the first breaking force of the aluminum wire corresponding to the current forest fire area is the minimum breaking force of the aluminum wire in the current forest fire area. The second breaking force of the steel strand corresponding to the current forest fire area is the minimum breaking force of the steel strand in the current forest fire area.

[0106] Then, based on the minimum breaking force of each steel strand and aluminum wire calculated above, the minimum breaking force of each layer of aluminum strand and the minimum breaking force of each layer of steel core, i.e., the first comprehensive breaking force of each layer of aluminum strand and the second comprehensive breaking force of each layer of steel core, can be further calculated.

[0107] Illustratively, if the breaking force of each layer is directly calculated, there may be a large error due to uneven distribution of materials, temperature differences and other factors. However, in the embodiment of the present application, the breaking force of each wire is first calculated, and then the results are summarized, which can more effectively control the calculation error of the breaking force, thereby overcoming the problem of different temperature deviations between the inner and outer layers of the power transmission conductor under forest fire conditions, and improving the accuracy of the breaking force evaluation.

[0108] For step S4, the first breaking force of each aluminum wire corresponding to the current forest fire area and the second breaking force of each steel strand corresponding to the current forest fire area are first calculated by step S3, and then summarized to the breaking force of the aluminum strand and the breaking force of each layer of steel core, and then the breaking force of the whole power transmission conductor corresponding to the current forest fire area is obtained, which can realize more refined evaluation.

[0109] In a preferred embodiment, the structural parameters of the power transmission conductor include the structural parameters of the aluminum wire and the structural parameters of the steel strand; the thermal expansion performance parameters of the power transmission conductor include the thermal expansion performance parameters of the aluminum wire and the thermal expansion performance parameters of the steel strand.

[0110] Then, when generating the third breaking force of the power transmission conductor corresponding to the current forest fire area according to the total number of aluminum wires, the total number of steel strands, the first breaking force corresponding to each aluminum wire, the second breaking force corresponding to each steel strand, the structural parameters of the power transmission conductor and the thermal expansion performance parameters of the power transmission conductor, it can specifically include:

[0111] According to the number of aluminum wires in each layer of aluminum strand, the structural parameters of the aluminum wire, the thermal expansion performance parameters of the aluminum wire and the first breaking force corresponding to each aluminum wire in each layer of aluminum strand, the first comprehensive breaking force of each layer of aluminum strand is generated.

[0112] generate the second comprehensive breaking force of each layer of steel core according to the number of steel strands of each layer of steel core, the structural parameters of the steel strands, the thermal expansion performance parameters of the steel strands, and the second breaking force corresponding to each steel strand in each layer of steel core;

[0113] generate the third breaking force of the power transmission conductor in the current forest fire area according to the first comprehensive breaking force of each layer of aluminum strand, the first preset breaking force coefficient corresponding to the aluminum strand, the second comprehensive breaking force of each layer of steel core, and the second preset breaking force coefficient corresponding to the steel core.

[0114] In a preferred embodiment, the structural parameters of the aluminum wire include: the number of segments of the aluminum wire corresponding to the current forest fire area, the elastic modulus of the aluminum wire, the cross-sectional area of the aluminum wire, and the length of the aluminum wire corresponding to the current forest fire area;

[0115] The thermal expansion performance parameters of the aluminum wire include: the linear thermal expansion coefficient of the aluminum wire and the average temperature of each segment length of the aluminum wire;

[0116] Then, when calculating the first comprehensive breaking force of each layer of aluminum strand, specifically:

[0117] Obtain the area temperature corresponding to the current forest fire area;

[0118] For each aluminum wire, generate the length change amount corresponding to the aluminum wire when the temperature rises according to the area temperature, the linear thermal expansion coefficient of the aluminum wire, the number of segments of the aluminum wire corresponding to the current forest fire area, and the average temperature of each segment length of the aluminum wire;

[0119] For each layer of aluminum strand, generate the external tension corresponding to the aluminum strand when the temperature rises according to the length change amount corresponding to each aluminum wire when the temperature rises, the elastic modulus of each aluminum wire, the cross-sectional area of each aluminum wire, the length of the aluminum wire corresponding to the current forest fire area, and the number of aluminum wires of the aluminum strand.

[0120] For each layer of aluminum strand, generate the first comprehensive breaking force of the aluminum strand according to the external tension corresponding to the aluminum strand when the temperature rises and the first breaking force corresponding to each aluminum wire in the aluminum strand.

[0121] In a preferred embodiment, the structural parameters of the steel strand include: the number of segments of the steel strand corresponding to the current forest fire area, the elastic modulus of the steel strand, the cross-sectional area of the steel strand, and the length of the steel strand corresponding to the current forest fire area;

[0122] The thermal expansion performance parameters of the steel strand include: the linear thermal expansion coefficient of the steel strand and the average temperature of each segment length of the steel strand;

[0123] Then, when calculating the second comprehensive breaking force of each layer of steel core, specifically:

[0124] obtaining a region temperature corresponding to a current wildfire region;

[0125] For each steel strand, a length change amount of the steel strand corresponding to temperature rise is generated according to the region temperature, a linear thermal expansion coefficient of the steel strand, a number of segments of the steel strand corresponding to the current wildfire region, and an average temperature of each segment length of the steel strand;

[0126] For each layer of steel core, an external tension of the steel core corresponding to temperature rise is generated according to the length change amount of each steel strand corresponding to temperature rise, an elastic modulus of each steel strand, a cross-sectional area of each steel strand, a length of each steel strand corresponding to the current wildfire region, and a number of steel strands of the steel core.

[0127] For each layer of steel core, a second comprehensive breaking force of the steel core is generated according to the external tension of the steel core corresponding to temperature rise and a second breaking force corresponding to each steel strand in the steel core.

[0128] Therefore, by considering the specific structural parameters (such as the number of segments, the elastic modulus, the cross-sectional area, and the length of the aluminum wire and the steel strand) and the thermal expansion performance parameters (such as the linear thermal expansion coefficient and the average temperature per unit length) of the power transmission conductor, the first comprehensive breaking force of each layer of aluminum wire strand and the second comprehensive breaking force of each layer of steel core can be calculated first, and then the first preset breaking force coefficient corresponding to the aluminum wire strand and the second preset breaking force coefficient corresponding to the steel core are combined to obtain the third breaking force of the power transmission conductor corresponding to the current wildfire region.

[0129] Since the aluminum wire and the steel strand are the main components of the power transmission conductor, their performance directly affects the performance of the entire power transmission conductor. By considering the structural parameters and the thermal expansion performance parameters of the aluminum wire and the steel strand respectively, the mechanical performance of the power transmission conductor under different conditions can be more accurately evaluated, and the stress condition and the breaking risk of the power transmission conductor under extreme conditions such as wildfires can be more accurately predicted.

[0130] Illustratively, the first comprehensive breaking force of each layer of aluminum wire strand is the minimum breaking force of each layer of aluminum wire strand. The second comprehensive breaking force of each layer of steel core is the minimum breaking force of each layer of steel core.

[0131] In a preferred embodiment, when calculating the minimum breaking force of each layer of aluminum wire strand based on the first breaking force corresponding to each aluminum wire, the following formula can be used for calculation:

[0132]

[0133] where ΔL n is the length change amount of the n th aluminum wire corresponding to temperature rise, which reflects the thermal expansion effect of the aluminum wire due to temperature rise, α is the linear thermal expansion coefficient of the aluminum wire, T iT is the average temperature of the i-th segment length, T ref x is the number of segments corresponding to the current wildfire area, F me E is the external tension corresponding to the temperature rise of the m-th layer of aluminum wire strands, used to evaluate the stress state of the aluminum wire strands, E n E is the elastic modulus of the n-th aluminum wire, A n A is the cross-sectional area of the n-th aluminum wire, k is the number of aluminum wires in the m-th layer of aluminum wire strands, L is the length of the aluminum wire in the current wildfire area, F2 is the first comprehensive breaking force of the m-th layer of aluminum wire strands, and F2 is the first breaking force of each aluminum wire in the current wildfire area.

[0134] Illustratively, when calculating the second comprehensive breaking force of each layer of steel core, the formula and principle for calculating the first comprehensive breaking force of each layer of aluminum wire strands are also used, which will not be repeated here.

[0135] In the evaluation of breaking force, the parameters considered cover multiple aspects of aluminum wire and steel strand, including their structural characteristics (such as elastic modulus, cross-sectional area, length, etc.), thermal expansion performance (such as linear thermal expansion coefficient, average temperature, etc.), and specific stress conditions (such as external tension, breaking force, etc.). In the actual wildfire impact process, the aluminum wire and steel strand may be affected by various factors, such as temperature gradient, material non-uniformity, complexity of external load, etc. Therefore, by comprehensively considering multiple parameters, the present application can more comprehensively evaluate the influence of these factors on the breaking force, thereby obtaining more accurate evaluation results.

[0136] Illustratively, the average temperature of each meter of conductor is used to simplify the calculation of conductor expansion length during the occurrence of wildfire, which reduces the complexity of calculation while considering the influence of different regional wildfire temperatures on the breaking force of the conductor.

[0137] Moreover, by analyzing the breaking force of each aluminum wire and steel strand under high temperature, the minimum breaking force of each layer of aluminum wire and steel strand is calculated while considering the conductor expansion stress, thereby improving the accuracy of the comprehensive breaking force calculation results of the conductor under wildfire conditions.

[0138] In a preferred embodiment, the minimum breaking force of the whole steel core aluminum strand conductor (i.e. the third breaking force of the power transmission conductor in the current wildfire area) is calculated as follows:

[0139] F = δF L + βF G ;

[0140] In the formula, F is the third breaking force of the power transmission conductor in the current wildfire area, δ is the first preset breaking force coefficient corresponding to the aluminum wire strands, β is the second preset breaking force coefficient corresponding to the steel core, and FL F is the sum of the breaking forces of each layer of aluminum wire strands. G This is the sum of the tensile forces of each layer of steel core.

[0141] For illustrative purposes, when the total number of aluminum wires is less than 37, δ = 0.95; when the total number of aluminum wires is greater than or equal to 37, δ = 0.9. When the total number of steel strands is less than 7, β = 0.93; when the total number of steel strands is greater than or equal to 7, β = 0.85.

[0142] In a preferred embodiment, step S5 compares the third breaking force of the transmission line in the current wildfire area with the preset breaking force threshold of the transmission line. If the third breaking force is less than the preset breaking force threshold of the transmission line, it indicates that the transmission line's ability to withstand tension is lower than the preset safety threshold. This generates an early warning message to indicate the risk of breakage of the transmission line, allowing for the early detection of potential breakage risks and enabling the implementation of necessary preventative measures (such as enhanced monitoring, adjustment of operating modes, and increased maintenance frequency) to effectively reduce the probability and consequences of accidents.

[0143] like Figure 3 The flowchart shown illustrates the process of calculating breaking force and issuing early warning for conductor breakage. This invention can obtain information about the location of wildfires from transmission line ledgers, control a drone equipped with an infrared thermal imager to acquire images of the outer temperature distribution of the conductor, and upload them to the control center. Based on solid-state heat transfer and fluid-solid-state heat transfer, the temperature of each aluminum wire and steel strand is iteratively calculated. Based on the maximum temperature of each aluminum wire and steel strand, the minimum breaking force of each steel strand and aluminum wire is calculated, thereby obtaining the minimum breaking force of the composite conductor. The minimum breaking force of the conductor is compared with the initially set breaking force threshold range to assess the risk level of conductor breakage, and corresponding early warning and control measures are implemented based on the risk level.

[0144] In illustrative terms, this embodiment of the invention allows for the monitoring of power lines by using an infrared thermal imager mounted on a drone after a wildfire, acquiring images of the temperature distribution of the outermost aluminum strands of the power line. The thermal imager converts the infrared radiation signal into a digital signal and transmits it in real time to the computing system of the ground control center via a wireless communication module.

[0145] The images transmitted from the thermal imager are analyzed to identify the conductor's outline and temperature information. Combined with structural information about the conductor (number of aluminum wire layers, number of strands per layer, number of steel strand layers, and number of strands per layer, etc.) from transmission line ledgers or construction records, iterative calculations using solid-state heat transfer and solid-fluid heat transfer methods are performed to obtain the real-time temperature, minimum breaking force of each aluminum wire and steel strand, and the overall minimum breaking force F of the transmission conductor. calculate .

[0146] When F calculate <Fmin-threshold If F < Fmin, then it is determined that the conductor has a high risk of breaking, marked as a red warning level;

[0147] When F min-threshold If F < Fmin, then it is determined that the conductor has a high risk of breaking, marked as a red warning level; calculate If Fmin < F < Fmax, then it is determined that the conductor has a moderate risk of breaking, marked as a yellow warning level; max-threshold If Fmin < F < Fmax, then it is determined that the conductor has a moderate risk of breaking, marked as a yellow warning level;

[0148] When F calculate If Fmin < F < Fmax, then it is determined that the conductor has a moderate risk of breaking, marked as a yellow warning level; max-threshold If F > Fmax, then it is determined to be low risk, marked as a green safe level.

[0149] When it is determined that the conductor has a breaking risk (red or yellow warning), according to the identification information of the conductor (number obtained from the transmission line account), geographical location information (longitude and latitude coordinates obtained by the GPS positioning system carried by the unmanned aerial vehicle, combined with the tower number and the relative position of the conductor in the span to determine the accurate position), risk level, calculated minimum breaking force value, real-time temperature data, etc., detailed warning text information is generated using natural language processing technology, and the warning information is converted into data in a specific format (such as JSON format) for easy transmission and processing. And add labels such as timestamp, device number, risk type code to the warning information, so that the monitoring center can quickly identify and classify.

[0150] The warning information can also be sent to the server of the regional monitoring center through the optical fiber communication network. When the server successfully receives the warning information, it immediately returns an acknowledgement signal to the sending end. If the sending end does not receive the acknowledgement signal within a specified time (such as seconds), it will resend the warning information to ensure that the warning information reaches the monitoring center accurately and without error.

[0151] Further, when a red warning occurs, it can also automatically connect to the control system of the intelligent fire extinguishing equipment deployed around, so as to calculate the best deployment position and spray angle of the fire extinguishing equipment according to the position and spread direction information of the forest fire returned by the unmanned aerial vehicle, and the position and spread direction information of the conductor. And send flight path planning instructions to the unmanned aerial vehicle fire extinguishing cluster to make it fly to the target area carrying fire extinguishing bombs or dry powder extinguishing agent for fire extinguishing operation.

[0152] When a yellow warning or higher level is triggered, it can also interact with the intelligent power grid control system of the power grid dispatching center to obtain real-time operation data of the current power transmission network, including load current, voltage, power factor and other parameters of each line, as well as output power of power supply point and available capacity of standby line and other information. Under the premise of meeting the safety operation constraints of the power grid, the optimal line reconstruction scheme is calculated to gradually transfer the load of the line with the risk conductor to the safe standby line.

[0153] Illustratively, after the mountain fire ends, all data of the conductor during the mountain fire can be collected and sorted, including the minimum breaking force change curve, the temperature change curve, the control measure implementation record (such as the operation log of the fire extinguishing equipment, the line switching time and sequence, the lifting record of the support tower, etc.), the mountain fire development trajectory (the data of the change of the flame position and intensity with time), etc., and the broken and scattered conductors in the mountain fire environment are replaced.

[0154] Therefore, by monitoring and calculating the breaking force of the power transmission conductor in real time and comparing it with the preset safety threshold, the potential risk of fracture can be found in time, so that preventive measures such as strengthening monitoring, adjusting the operation mode or increasing the maintenance frequency can be taken to effectively avoid accidents.

[0155] As shown in the above various embodiments of the power transmission conductor fracture risk early warning method based on the mountain fire condition, Figure 4 corresponding device embodiments are provided by the present application based on the above various embodiments of the power transmission conductor fracture risk early warning method based on the mountain fire condition;

[0156] An embodiment of the present application provides a power transmission conductor fracture risk early warning device based on a mountain fire condition, comprising: a conductor surface temperature acquisition module, a temperature simulation result generation module, a first calculation module, a second calculation module and an early warning module;

[0157] The conductor surface temperature acquisition module is configured to acquire the surface temperature of the power transmission conductor in the current mountain fire area; wherein the power transmission conductor comprises a plurality of aluminum wires and a plurality of steel strands;

[0158] The temperature simulation result generation module is configured to perform simulation calculation of heat transfer based on the convection heat transfer model between the power transmission conductor and the air, the heat conduction model between the aluminum wire and the steel strand and the surface temperature, and generate the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand;

[0159] The first calculation module is configured to generate the first breaking force corresponding to each aluminum wire in the current mountain fire area according to the temperature simulation result of each aluminum wire and the first preset breaking force of each aluminum wire when no mountain fire occurs, and generate the second breaking force corresponding to each steel strand in the current mountain fire area according to the temperature simulation result of each steel strand and the second preset breaking force of each steel strand when no mountain fire occurs;

[0160] The second calculation module is configured to generate the third breaking force corresponding to the power transmission conductor in the current mountain fire area according to the total number of aluminum wires, the total number of steel strands, the first breaking force corresponding to each aluminum wire, the second breaking force corresponding to each steel strand, the structural parameters of the power transmission conductor and the thermal expansion performance parameters of the power transmission conductor;

[0161] The pre-warning module is configured to generate pre-warning information for indicating that the power transmission conductor is at risk of fracture when it is determined that the third breaking force is less than the preset breaking force threshold corresponding to the power transmission conductor.

[0162] It should be noted that the apparatus embodiments described above are merely illustrative, and the modules described as separate components can or can not be physically separated, and the components displayed as modules can or can not be physical modules, and can be located in one place or distributed on multiple network modules. Part or all of the modules can be selected to achieve the purpose of the embodiment according to actual needs. In addition, the connection relationship between the modules in the apparatus embodiments provided by the present application indicates that there is a communication connection between them, which can be implemented as one or more communication buses or signal lines. Those skilled in the art can understand and implement it without creative labor.

[0163] Those skilled in the art can clearly understand that, for the convenience and brevity, the specific working process of the apparatus described above can refer to the corresponding process in the foregoing method embodiments, which will not be described here.

[0164] On the basis of the various embodiments of the power transmission conductor fracture risk pre-warning method under the mountain fire condition described above, the present application correspondingly provides terminal device embodiments.

[0165] An embodiment of the present application provides a terminal device, which comprises a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, and the processor implements a power transmission conductor fracture risk pre-warning method under a mountain fire condition according to any one of the method embodiments of the present application when executing the computer program.

[0166] The terminal device can be a desktop computer, a notebook computer, a palm computer, a cloud server, and other computing terminal devices. The terminal device can include, but is not limited to, a processor and a memory.

[0167] The processor can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The processor is a control center of the terminal device, and connects all parts of the terminal device through various interfaces and lines.

[0168] The memory can be used to store the computer program, and the processor realizes various functions of the terminal device by running or executing the computer program stored in the memory, and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application required by a function, etc.; and the data storage area can store data created according to the use of the mobile phone, etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, at least one disk storage device, a flash memory device or other volatile solid-state memory device.

[0169] On the basis of the above-mentioned various embodiments of the power transmission line fracture risk early warning method based on mountain fire conditions, the application correspondingly provides a storage medium embodiment.

[0170] An embodiment of the application provides a storage medium, which comprises a stored computer program, wherein when the computer program runs, the device where the computer readable storage medium is located executes a power transmission line fracture risk early warning method based on mountain fire conditions.

[0171] The storage medium is a computer readable storage medium, and the computer program is stored in the computer readable storage medium. When the computer program is executed by a processor, steps of each method embodiment described above can be implemented. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or some intermediate forms, etc. The computer readable medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the content included in the computer readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction, for example, in some jurisdictions, according to legislation and patent practice, the computer readable medium does not include electrical carrier signals and telecommunication signals.

[0172] The above is the preferred embodiment of the present application. It should be noted that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, which are also considered within the scope of protection of the present application.

Claims

1. A method for early warning of the risk of transmission line fracture under forest fire conditions, characterized in that, The method comprises the following steps: acquiring the surface temperature of the power transmission conductor in the current forest fire area; wherein the power transmission conductor comprises a plurality of aluminum wires and a plurality of steel strands; generating the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand based on the simulation calculation of heat transfer of the convection heat transfer model between the power transmission conductor and the air, the heat conduction model between the aluminum wire and the steel strand and the surface temperature; generating the first breaking force of each aluminum wire in the current forest fire area according to the temperature simulation result of each aluminum wire and the first preset breaking force of each aluminum wire when no forest fire occurs; generating the second breaking force of each steel strand in the current forest fire area according to the temperature simulation result of each steel strand and the second preset breaking force of each steel strand when no forest fire occurs; generating the third breaking force of the power transmission conductor in the current forest fire area according to the total number of aluminum wires, the total number of steel strands, the first breaking force of each aluminum wire, the second breaking force of each steel strand, the structural parameters of the power transmission conductor and the thermal expansion performance parameters of the power transmission conductor; generating the early warning information for indicating the breaking risk of the power transmission conductor when the third breaking force is smaller than the preset breaking force threshold of the power transmission conductor; wherein the power transmission conductor comprises a plurality of layers of aluminum wire strands and a plurality of layers of steel cores; the surface temperature is the temperature corresponding to the outermost layer of aluminum wire strand of the power transmission conductor; each layer of aluminum wire strand contains a plurality of aluminum wires, and each layer of steel core contains a plurality of steel strands; the simulation calculation of heat transfer of the convection heat transfer model between the power transmission conductor and the air, the heat conduction model between the aluminum wire and the steel strand and the surface temperature, to generate the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand, comprises: performing simulation modeling on the power transmission conductor according to the total number of layers of aluminum wire strands, the number of aluminum wires of each layer of aluminum wire strand, the total number of layers of steel cores and the number of steel strands of each layer of steel core, to generate the simulation model corresponding to the power transmission conductor; constructing the convection heat transfer model between the power transmission conductor and the air according to the convection heat transfer coefficient, the surface temperature of the power transmission conductor and the air temperature; constructing the heat conduction model between the aluminum wire and the steel strand according to the thermal conductivity coefficient of the aluminum wire, the thermal conductivity coefficient of the steel core and the Fourier law; after taking the surface temperature as the boundary temperature of the simulation model, performing the simulation calculation of heat transfer of the simulation model, the convection heat transfer model and the heat conduction model, and outputting the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand.

2. The method for predicting the risk of transmission line breakage under mountain fire conditions according to claim 1, characterized in that, the simulation calculation of heat transfer of the simulation model, the convection heat transfer model and the heat conduction model, to output the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand, comprises: repeating the following temperature generation operation until the current iteration number is the same as the preset iteration number: taking the highest temperature of each aluminum wire in all simulation calculation operations as the temperature simulation result corresponding to each aluminum wire, and taking the highest temperature of each steel strand in all simulation calculation operations as the temperature simulation result corresponding to each steel strand. obtain a current temperature of each aluminum wire and a current temperature of each steel strand; when the current iteration number is less than the preset iteration number, perform heat transfer simulation calculation on the simulation model, the convection heat transfer model and the heat conduction model according to the current temperature of each aluminum wire and the current temperature of each steel strand, and output the temperature of each aluminum wire in the current simulation calculation operation and the temperature of each steel strand in the current simulation calculation operation; wherein initially, the current temperature of each aluminum wire and the current temperature of each steel strand are generated according to the surface temperature of the power transmission conductor and Fourier's law; the temperature of each aluminum wire in the current simulation calculation operation is taken as the current temperature of each aluminum wire in the next temperature generation operation, and the temperature of each steel strand in the current simulation calculation operation is taken as the current temperature of each steel strand in the next temperature generation operation.

3. The method for predicting the risk of transmission line breakage under mountain fire conditions according to claim 2, characterized in that, The structural parameters of the power transmission conductor include the structural parameters of the aluminum wire and the structural parameters of the steel strand. The thermal expansion performance parameters of the power transmission conductor include the thermal expansion performance parameters of the aluminum wire and the thermal expansion performance parameters of the steel strand. The generation of the third breaking force corresponding to the power transmission conductor in the current forest fire area according to the total number of aluminum wires, the total number of steel strands, the first breaking force corresponding to each aluminum wire, the second breaking force corresponding to each steel strand, the structural parameters of the power transmission conductor and the thermal expansion performance parameters of the power transmission conductor includes: generating the first comprehensive breaking force of each layer of aluminum wire strand according to the number of aluminum wires in each layer of aluminum wire strand, the structural parameters of the aluminum wire, the thermal expansion performance parameters of the aluminum wire and the first breaking force corresponding to each aluminum wire in each layer of aluminum wire strand; generating the second comprehensive breaking force of each layer of steel core according to the number of steel strands in each layer of steel core, the structural parameters of the steel strand, the thermal expansion performance parameters of the steel strand and the second breaking force corresponding to each steel strand in each layer of steel core; generating the third breaking force corresponding to the power transmission conductor in the current forest fire area according to the first comprehensive breaking force of each layer of aluminum wire strand, the first preset breaking force coefficient corresponding to the aluminum wire strand, the second comprehensive breaking force of each layer of steel core and the second preset breaking force coefficient corresponding to the steel core.

4. The method of claim 3, wherein the method is based on a risk of a transmission line breakage under a wildfire condition. The structural parameters of the aluminum wire include the number of segments corresponding to the aluminum wire in the current forest fire area, the elastic modulus of the aluminum wire, the cross-sectional area of the aluminum wire and the length corresponding to the aluminum wire in the current forest fire area. The thermal expansion performance parameters of the aluminum wire include the linear thermal expansion coefficient of the aluminum wire and the average temperature of each segment length of the aluminum wire. The generation of the first comprehensive breaking force of each layer of aluminum wire strand according to the number of aluminum wires in each layer of aluminum wire strand, the structural parameters of the aluminum wire, the thermal expansion performance parameters of the aluminum wire and the first breaking force corresponding to each aluminum wire in each layer of aluminum wire strand includes: obtain the area temperature corresponding to the current forest fire area; for each aluminum wire, generate the length change amount corresponding to the aluminum wire when the temperature rises according to the area temperature, the linear thermal expansion coefficient of the aluminum wire, the number of segments corresponding to the aluminum wire in the current forest fire area and the average temperature of each segment length of the aluminum wire. For each layer of aluminum strand, according to the length change amount corresponding to each aluminum wire at temperature rise, the elastic modulus of each aluminum wire, the cross-sectional area of each aluminum wire, the length corresponding to the aluminum wire in the current forest fire area and the number of aluminum wires of the aluminum strand, the external tension corresponding to the aluminum strand at temperature rise is generated; For each layer of aluminum strand, according to the external tension corresponding to the aluminum strand at temperature rise and the first breaking force corresponding to each aluminum wire in the aluminum strand, the first comprehensive breaking force of the aluminum strand is generated.

5. A device for predicting the risk of a power transmission line breaking under wildfire conditions, characterized in that it comprises: Comprise: Conductor surface temperature acquisition module, temperature simulation result generation module, first calculation module, second calculation module and early warning module; The conductor surface temperature acquisition module is used for acquiring the surface temperature of the power transmission conductor in the current forest fire area; wherein the power transmission conductor comprises a plurality of aluminum wires and a plurality of steel strands; The temperature simulation result generation module is used for performing heat transfer simulation calculation based on the convective heat transfer model between the power transmission conductor and the air, the heat conduction model between the aluminum wire and the steel strand and the surface temperature to generate the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand; The first calculation module is used for generating the first breaking force corresponding to each aluminum wire in the current forest fire area according to the temperature simulation result of each aluminum wire and the first preset breaking force of each aluminum wire when no forest fire occurs; generating the second breaking force corresponding to each steel strand in the current forest fire area according to the temperature simulation result of each steel strand and the second preset breaking force of each steel strand when no forest fire occurs; The second calculation module is used for generating the third breaking force corresponding to the power transmission conductor in the current forest fire area according to the total number of aluminum wires, the total number of steel strands, the first breaking force corresponding to each aluminum wire, the second breaking force corresponding to each steel strand, the structural parameters of the power transmission conductor and the thermal expansion performance parameters of the power transmission conductor; The early warning module is used for generating early warning information for indicating that the power transmission conductor has a risk of fracture when it is determined that the third breaking force is less than the preset breaking force threshold corresponding to the power transmission conductor; Wherein, the power transmission conductor comprises a plurality of layers of aluminum strands and a plurality of layers of steel cores; the surface temperature is the temperature corresponding to the outermost layer of aluminum strand of the power transmission conductor; wherein each layer of aluminum strand contains a plurality of aluminum wires, and each layer of steel core contains a plurality of steel strands; The simulation calculation of heat transfer based on the convective heat transfer model between the power transmission conductor and the air, the heat conduction model between the aluminum wire and the steel strand and the surface temperature to generate the temperature simulation result of each aluminum wire and the temperature simulation result of each steel strand, comprises: According to the total number of layers of aluminum strands, the number of aluminum wires of each layer of aluminum strand, the total number of layers of steel cores and the number of steel strands of each layer of steel core, the power transmission conductor is simulated to generate the simulation model corresponding to the power transmission conductor; According to the convective heat transfer coefficient, the surface temperature of the power transmission conductor and the air temperature, the convective heat transfer model between the power transmission conductor and the air is constructed; According to the thermal conductivity coefficient of the aluminum wire, the thermal conductivity coefficient of the steel core and the Fourier law, the heat conduction model between the aluminum wire and the steel strand is constructed; After the surface temperature is taken as a boundary temperature of the simulation model, the simulation calculation of heat transfer of the simulation model, the convection heat transfer model and the heat conduction model is performed, and temperature simulation results of each aluminum wire and temperature simulation results of each steel strand are output.

6. A terminal device, characterized by comprising: The device comprises a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, and the processor implements the method for early warning of the fracture risk of the power transmission conductor under the mountain fire condition according to any one of claims 1 to 4 when the computer program is executed.

7. A storage medium, characterized by The storage medium comprises a stored computer program, wherein the device where the storage medium is located performs the method for early warning of the fracture risk of the power transmission conductor under the mountain fire condition according to any one of claims 1 to 4 when the computer program is executed.

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