Method and device for determining thickness of metal sheath of cable and electronic equipment

Abstract

The invention discloses a method and device for determining the thickness of a metal sheath of a cable and electronic equipment. The method comprises the following steps: acquiring a target cable; determining cable parameters of the target cable; constructing a target cable model of finite element simulation according to the cable parameters; setting a mechanical simulation boundary condition corresponding to the target cable model, and setting an electrothermal coupling simulation boundary condition corresponding to the target cable model; according to a mechanical simulation boundary condition and a target cable model, adjusting the first initial thickness to obtain a first target thickness, and according to an electrothermal coupling simulation boundary condition and the target cable model, adjusting the second initial thickness to obtain a second target thickness; and determining a metal sheath thickness interval corresponding to the target cable according to the first target thickness and the second target thickness. According to the invention, the technical problem that the determined thickness of the metal sheath of the cable is usually set to be a fixed thickness, is not targeted and is difficult to adapt to the change of the environment in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the field of power cables, and in particular to a method and device for determining the thickness of a metal sheath of a cable, and electronic equipment. Background Art

[0002] At present, the power load demand in some large and medium-sized cities is increasing, and the voltage level is gradually increasing. In order to adapt to the high-density load and complex wiring methods of urbanization, as well as to take into account the needs of urban appearance, many large and medium-sized urban power grids choose to use high-voltage and large-section cables for urban power grid construction, and they are the best choice from the three aspects of safety, economy and service life. The power grids in large and medium-sized cities are developing rapidly, and the demand for cable lines with better safety performance, larger transmission capacity and longer service life is gradually increasing.

[0003] However, when setting the metal sheath of the cable, due to environmental changes and the increase in cable usage time, there are safety issues such as erosion of the buffer layer of the corrugated aluminum high-voltage cable. In addition, due to the differences in cables, no targeted treatment is performed when setting up protection for the cables.

[0004] To address the above-mentioned problems, no effective solution has been proposed yet. Summary of the invention

[0005] The embodiments of the present invention provide a method, device and electronic device for determining the thickness of the metal sheath of a cable, so as to at least solve the technical problem in the related art that the determined thickness of the metal sheath of the cable is usually set to a fixed thickness, which is not targeted and difficult to adapt to environmental changes.

[0006] According to one aspect of an embodiment of the present invention, a method for determining the thickness of a metal sheath of a cable is provided, comprising: obtaining a target cable, wherein the target cable includes at least a metal sheath; determining cable parameters of the target cable, wherein the cable parameters include: structural parameters, electrothermal parameters, and mechanical characteristic parameters; constructing a target cable model of finite element simulation based on the cable parameters, and setting a first initial thickness and a second initial thickness of the metal sheath; setting mechanical simulation boundary conditions corresponding to the target cable model, and setting electrothermal coupling simulation boundary conditions corresponding to the target cable model; adjusting the first initial thickness based on the mechanical simulation boundary conditions and the target cable model to obtain a first target thickness, and adjusting the second initial thickness based on the electrothermal coupling simulation boundary conditions and the target cable model to obtain a second target thickness; determining a metal sheath thickness interval corresponding to the target cable based on the first target thickness and the second target thickness.

[0007] Optionally, the first initial thickness is adjusted according to the mechanical simulation boundary conditions and the target cable model to obtain a first target thickness, including: determining the safety factor distribution parameters obtained by simulating the target cable model under the mechanical simulation boundary conditions under the first initial thickness; if the safety factor distribution parameters do not exist within the first distribution parameter range, increasing the first initial thickness until the obtained safety factor distribution exists within the first distribution parameter range to obtain the first target thickness.

[0008] Optionally, the second initial thickness is adjusted according to the electrothermal coupling simulation boundary conditions and the target cable model to obtain a second target thickness, including: determining the temperature field distribution parameters obtained by simulating the target cable model under the electrothermal coupling simulation boundary conditions under the second initial thickness; when the temperature field distribution parameters do not exist within the second distribution parameter range, reducing the second initial thickness until the obtained temperature field distribution parameters exist within the second distribution parameter range to obtain the second target thickness.

[0009] Optionally, mechanical simulation boundary conditions corresponding to the target cable model are set, and electrothermal coupling simulation boundary conditions corresponding to the target cable model are set, including: determining the downward pressing distance and short-circuit bearing capacity of the bending pressure head corresponding to the target cable model according to the scenario parameters applied by the target cable; setting the mechanical simulation boundary conditions corresponding to the target cable model according to the downward pressing distance, and setting the electrothermal coupling simulation boundary conditions corresponding to the target cable model according to the short-circuit bearing capacity.

[0010] Optionally, based on the scenario parameters applied by the target cable, the bending pressure head pressing distance corresponding to the target cable model is determined, including: determining the bending radius corresponding to the target cable model, the distance between the first support and the second support in the target cable model, the support radius, the pressure head radius, and the nominal outer diameter of the target cable; determining the bending pressure head pressing distance based on the bending radius, the distance, the support radius, the pressure head radius and the nominal outer diameter of the cable.

[0011] Optionally, the short-circuit capacity is determined based on the scenario parameters in which the target cable is applied, including: based on a benchmark capacity, a benchmark voltage, a short-circuit capacity of the target cable, a per-unit reactance value and a per-unit resistance value between the target cable and an upstream transformer, and a per-unit impedance value of a system in which the target cable is located; the short-circuit capacity is determined based on the benchmark capacity, the benchmark voltage, the short-circuit capacity, the per-unit impedance value, the per-unit reactance value and the per-unit resistance value.

[0012] Optionally, after determining the metal sheath thickness range corresponding to the target cable based on the first target thickness and the second target thickness, it also includes: setting the thickness of the metal sheath in the target cable to a thickness value in the metal sheath thickness range to obtain an implementation cable, so that the implementation cable is used to implement power transmission.

[0013] According to one aspect of an embodiment of the present invention, a device for determining the thickness of a metal sheath of a cable is provided, comprising: an acquisition module for acquiring a target cable, wherein the target cable at least comprises a metal sheath; a first determination module for determining cable parameters of the target cable, wherein the cable parameters comprise structural parameters, electrothermal parameters, and mechanical characteristic parameters; a construction module for constructing a target cable model of finite element simulation according to the cable parameters, and setting a first initial thickness and a second initial thickness of the metal sheath; a setting module for setting mechanical simulation boundary conditions corresponding to the target cable model, and setting an electrothermal coupling simulation boundary conditions corresponding to the target cable model; an adjustment module for adjusting the first initial thickness according to the mechanical simulation boundary conditions and the target cable model to obtain a first target thickness, and adjusting the second initial thickness according to the electrothermal coupling simulation boundary conditions and the target cable model to obtain a second target thickness; and a second determination module for determining a metal sheath thickness interval corresponding to the target cable according to the first target thickness and the second target thickness.

[0014] According to one aspect of an embodiment of the present invention, there is provided an electronic device, comprising: a processor; and a memory for storing instructions executable by the processor; wherein the processor is configured to execute the instructions to implement the method for determining the thickness of the metal sheath of a cable as described in any one of the above.

[0015] According to one aspect of an embodiment of the present invention, a computer-readable storage medium is provided. When instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device can execute any of the above-mentioned methods for determining the metal sheath thickness of a cable.

[0016] In an embodiment of the present invention, a target cable is obtained, wherein the target cable includes at least a metal sheath. Cable parameters of the target cable are determined, wherein the cable parameters include: structural parameters, electrothermal parameters, and mechanical characteristic parameters. Based on the cable parameters, a target cable model of finite element simulation is constructed, and a first initial thickness and a second initial thickness of the metal sheath are set. Mechanical simulation boundary conditions corresponding to the target cable model are set, and electrothermal coupling simulation boundary conditions corresponding to the target cable model are set. Based on the mechanical simulation boundary conditions and the target cable model, the first initial thickness is adjusted to obtain a first target thickness, and based on the electrothermal coupling simulation boundary conditions and the target cable model, the second initial thickness is adjusted to obtain a second target thickness. Based on the first target thickness and the second target thickness, a metal sheath thickness interval corresponding to the target cable is determined. It can be seen that the embodiment of the present invention obtains the structural parameters, electrothermal parameters, and mechanical characteristic parameters of the cable to set the thickness of the metal sheath in a targeted manner. In addition, the finite element model is used to simulate the conditions under the mechanical simulation boundary conditions and the electrothermal coupling simulation boundary conditions, and the thickness range that meets the safety requirements and temperature requirements is obtained to determine the appropriate thickness of the metal sheath, thereby solving the technical problem in the related art that the determined thickness of the cable metal sheath is usually set to a fixed thickness, which is not targeted and difficult to adapt to environmental changes. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0018] Figure 1 is a flow chart of a method for determining the thickness of a metal sheath of a cable according to an embodiment of the present invention;

[0019] Figure 2 A method flow chart providing a method for an optional embodiment of the present invention;

[0020] Figure 3 A schematic structural diagram of a smooth aluminum sheathed cable provided for an optional implementation manner of the present invention;

[0021] Figure 4 A schematic diagram of calculating the pressing distance of the indenter using the three-point bending method provided in an optional embodiment of the present invention;

[0022] Figure 5 A schematic diagram of the safety factor distribution of the three-layer composite structure of aluminum sheath-hot melt adhesive-outer sheath of a smooth aluminum sheathed cable provided in an optional embodiment of the present invention;

[0023] Figure 6 A schematic diagram of the thickness of each layer of a cable provided in an optional embodiment of the present invention;

[0024] Figure 7 4 is a structural block diagram of a device for determining the thickness of a metal sheath of a cable according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0026] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0027] Example 1

[0028] According to an embodiment of the present invention, an embodiment of a method for determining the thickness of a metal sheath of a cable is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0029] Figure 1 : is a flow chart of a method for determining the thickness of a metal sheath of a cable according to an embodiment of the present invention. Figure 1 As shown, the method comprises the following steps:

[0030] Step S102, obtaining a target cable, wherein the target cable at least includes a metal sheath;

[0031] In step S102 provided in the present application, it is explained that the target cable is obtained, and the target cable at least includes a metal sheath. Among them, the target cable is a cable selected according to performance requirements, environmental conditions, safety standards and other factors in a specific project, project or application. The target cable may be used in various occasions such as power transmission, signal transmission, and data communication. The metal sheath is a part of the cable structure, usually made of metal materials such as aluminum, copper, and steel. Its main functions include providing mechanical protection, enhancing the compression resistance and tensile strength of the cable, preventing external physical damage (such as animal bites, mechanical wear), and resisting electromagnetic interference (EMI) and radio frequency interference (RFI) to a certain extent. The metal sheath can also serve as a grounding layer to improve the safety of the cable system. Therefore, the metal sheath can play a role in protecting the cable, so it is particularly important to accurately determine its thickness.

[0032] The target cable may also include other structures, such as an insulation layer, a shielding layer, an outer sheath, etc., which can be customized according to actual applications and scenarios.

[0033] Step S104, determining the cable parameters of the target cable, wherein the cable parameters include: structural parameters, electrothermal parameters, and mechanical characteristic parameters;

[0034] In step S104 provided in the present application, the cable parameters of the target cable are determined, wherein the cable parameters include structural parameters, electrothermal parameters, and mechanical characteristic parameters.

[0035] The structural parameters may include parameters of the structural composition of the cable.

[0036] Among them, the electrothermal parameters may include resistivity, which is an important indicator of the conductive properties of the conductor material and affects the power loss and heat generation of the cable. It may also include current carrying capacity, which is the maximum current value that the cable can safely transmit under specific conditions, and is related to factors such as the conductor cross-sectional area, insulation material, and ambient temperature. It may also include insulation resistance, which measures the ability of the insulation layer to prevent current from passing through, ensuring that the cable does not leak during normal operation. It may also include thermal stability values, which are the ability of the cable to maintain stable performance in a high temperature environment to prevent damage due to overheating.

[0037] Among them, the mechanical characteristic parameters may also include tensile strength, the ability of the cable to withstand tensile force, to ensure that it does not break during laying and use. It may include bending radius, the minimum radius at which the cable is not damaged when bent, which affects the flexibility and installation convenience of the cable. It may include wear resistance, the ability of the cable outer sheath to resist wear and tear, and extend the service life of the cable. It may include compressive strength, the ability of the cable to withstand pressure, and so on.

[0038] In the scenario where the optional embodiment of the present invention is applied, the above parameters may include the outer radius r of the conductorc , conductor shield, cross-linked polyethylene XLPE insulation and insulation shield three-layer composite structure outer radius r x , buffer layer outer radius r b , hot melt adhesive thickness h h 、Outer sheath outer radius h p , Set the parameters to be determined: smooth aluminum sleeve, aluminum sleeve outer radius r s2 . Determine the XLPE Young's modulus E i , Poisson's ratio μ i , shaping parameters. When the metal sheath is an aluminum sheath, the Young's modulus E of the aluminum material of the cable aluminum sheath is s , Poisson's ratio μ s , shaping parameters. Hot melt adhesive tensile modulus Rm h , shear modulus G h , Shear Strength Breaking energy. Young's modulus E required for outer sheath p , Poisson's ratio μ p , shaping parameters, etc. can be adaptively adjusted according to actual applications.

[0039] Step S106, constructing a target cable model for finite element simulation according to the cable parameters, and setting a first initial thickness and a second initial thickness of the metal sheath;

[0040] In step S106 provided in the present application, a target cable model for finite element simulation is constructed based on the above cable parameters, wherein finite element simulation is a technology that uses mathematical approximation to simulate a real physical system. In the field of cables, by constructing a geometric model of the cable and assigning parameters such as material properties and boundary conditions to it, physical phenomena such as stress distribution, temperature field, and electromagnetic field of the cable under various working conditions can be simulated on a computer.

[0041] Based on the actual parameters of the cable (such as structural parameters, electrical and thermal parameters, mechanical characteristic parameters, etc.), a virtual model that is as similar as possible to the real cable is constructed in the finite element software. This model will serve as the basis for subsequent simulation analysis.

[0042] In this step, the first initial thickness and the second initial thickness of the metal sheath are also determined, wherein the first initial thickness can be a smaller thickness, such as being set to a thickness lower than the conventional thickness that can meet safety requirements, and the second initial thickness can be a larger thickness, such as being set to a thickness higher than the conventional thickness that meets temperature performance requirements, that is, when constructing a cable model, the metal sheath is an important component of the cable structure, and its thickness is a key parameter. Setting the first initial thickness and the second initial thickness may be to compare the effects of the metal sheath on the cable performance at different thicknesses. That is, the different performances of the cable under the mechanical and electrothermal coupling boundary conditions in the following steps can be considered at this thickness.

[0043] Step S108, setting a mechanical simulation boundary condition corresponding to the target cable model, and setting an electrothermal coupling simulation boundary condition corresponding to the target cable model;

[0044] In step S108 provided in the present application, two boundary conditions are set, one is a mechanical simulation boundary condition corresponding to the target cable model, and the other is an electrothermal coupling simulation boundary condition corresponding to the target cable model.

[0045] Among them, the mechanical simulation boundary conditions refer to various external mechanical effects or constraints imposed on the cable model during the mechanical simulation process to simulate the mechanical loads and boundary constraints to which the cable is subjected in the actual working environment. Among them, the boundary conditions can be multiple, for example, displacement constraints, which impose displacement constraints on certain parts of the cable model (such as the fixed end) to simulate the fixed state of the cable in actual installation. For example, load application constraints, which impose mechanical loads such as tension, pressure, and bending moment on the cable model to simulate various mechanical conditions that the cable may encounter during operation. For example, contact settings, if the cable model is in contact with other objects (such as brackets, pipes, etc.), it is necessary to set the corresponding contact pairs and contact properties to simulate the mechanical behavior during the contact process. It can test whether the above performance is still perfect under different thicknesses, whether the cable can still be effectively used, and whether the safety requirements are met.

[0046] Among them, the electrothermal coupling simulation boundary condition refers to the condition setting that considers the interaction between the electric field and the temperature field during the electrothermal coupling simulation. The setting of this boundary condition can be such as the relationship between conductivity and temperature. The conductivity of the cable material usually changes with the change of temperature. Therefore, it is necessary to set a curve or equation for the change of conductivity with temperature in the electrothermal coupling simulation. You can also set a heat source, such as setting a heat source in the cable model, such as the Joule heat generated by the current passing through the conductor, to simulate the heating of the cable during operation. You can also set thermal boundary conditions, set the heat exchange conditions between the cable model and the external environment, such as the convection heat transfer coefficient, the radiation heat transfer coefficient, etc., to simulate the heat dissipation of the cable. To test whether the heating, heat dissipation, temperature, etc. meet the requirements at different thicknesses.

[0047] By accurately setting the boundary conditions of mechanical simulation and electrothermal coupling simulation, it can be ensured that the simulation results at the corresponding thickness are closer to the performance of the cable in the actual working environment, improving the accuracy and reliability of the simulation. Moreover, based on the simulation results, the design of the cable can be optimized, that is, in addition to adjusting the thickness of the metal sheath, more suitable insulation materials can be selected, and the heat dissipation structure can be optimized to improve the performance and reliability of the cable.

[0048] Step S110, adjusting the first initial thickness according to the mechanical simulation boundary conditions and the target cable model to obtain the first target thickness, and adjusting the second initial thickness according to the electrothermal coupling simulation boundary conditions and the target cable model to obtain the second target thickness;

[0049] In step S110 provided in the present application, the first initial thickness (i.e., the preliminary design thickness of the metal sheath) is adjusted according to the mechanical simulation boundary conditions and the target cable model to meet the performance of the cable in terms of mechanical properties, thereby obtaining the first target thickness. Similarly, according to the electrothermal coupling simulation boundary conditions and the target cable model, the second initial thickness is similarly adjusted to meet the performance of the cable in terms of electrothermal coupling performance, thereby obtaining the second target thickness.

[0050] When determining the thickness of the metal sheath, on the one hand, when the thickness of the metal sheath of the smooth aluminum sheath cable increases, the bending radius of the smooth aluminum sheath cable increases, and the construction difficulty increases. On the other hand, when the thickness of the metal sheath decreases, the resistance per unit length of the metal sheath increases, and when the same short-circuit capacity flows, the heat of the metal sheath per unit length increases, affecting the performance of the outer sheath and hot melt adhesive. Therefore, it is necessary to consider both mechanical and temperature aspects to set a reasonable thickness of the metal sheath.

[0051] In the mechanical simulation, the first initial thickness is applied to the target cable model, and the corresponding mechanical simulation boundary conditions (such as displacement constraints, load application, contact settings, etc.) are applied. Through simulation analysis, the performance indicators such as stress distribution, deformation, fatigue life, etc. of the cable model under given mechanical conditions are evaluated. According to the simulation results, if it is found that the cable model has deficiencies in mechanical properties (such as stress concentration, excessive deformation, short fatigue life, etc.), the first initial thickness needs to be adjusted. The adjustment process may involve multiple iterations until the first target thickness that meets the mechanical performance requirements is found.

[0052] In the electrothermal coupling simulation, the second initial thickness is applied to the target cable model, and the corresponding electrothermal coupling simulation boundary conditions are set (such as the relationship between conductivity and temperature, heat source setting, thermal boundary conditions, etc.). Through simulation analysis, the performance indicators of the cable model such as temperature distribution, thermal stress, and aging of insulating materials under the action of electrothermal coupling are evaluated. According to the simulation results, if it is found that the cable model has deficiencies in electrothermal coupling performance (such as excessive temperature, excessive thermal stress, and too fast aging of insulating materials), the second initial thickness needs to be adjusted. Similarly, the adjustment process may also involve multiple iterations to find a second target thickness that can meet the electrothermal coupling performance requirements.

[0053] Step S112, determining a metal sheath thickness interval corresponding to the target cable according to the first target thickness and the second target thickness.

[0054] In step S112 provided in the present application, since the first target thickness is obtained through mechanical simulation analysis, the main focus is on the performance of the cable when subjected to various mechanical loads, such as stress distribution, deformation, fatigue life, etc. The second target thickness is obtained through electrothermal coupling simulation analysis, which mainly considers factors such as temperature distribution, thermal stress, and aging of insulating materials of the cable under electrothermal coupling. Therefore, when determining the metal sheath thickness interval, it is necessary to comprehensively weigh the needs of these two aspects. According to the specific values ​​of the first target thickness and the second target thickness, a reasonable metal sheath thickness interval can be determined. This interval should be able to meet the requirements of mechanical properties and electrothermal coupling performance at the same time, while taking into account a certain design margin and production error. Specifically, the larger value of the two target thicknesses can be used as the upper limit of the thickness interval to ensure that the cable can maintain good performance under various working conditions. The smaller value of the two target thicknesses (or appropriately reduced to consider the margin) is used as the lower limit of the thickness interval to avoid unnecessary material waste.

[0055] It should be noted that after the initial thickness range is determined, further adjustments and optimizations can be made based on the specific application scenarios, cost requirements, manufacturing processes and other factors of the cable. For example, if the cable needs to work in extreme environments, the thickness may need to be appropriately increased to improve its durability. If cost is the main consideration, the thickness can be minimized while ensuring performance.

[0056] Through the above steps S102-S112, the target cable is obtained, wherein the target cable includes at least a metal sheath. The cable parameters of the target cable are determined, wherein the cable parameters include: structural parameters, electrothermal parameters, and mechanical characteristic parameters. According to the cable parameters, a target cable model of finite element simulation is constructed, and a first initial thickness and a second initial thickness of the metal sheath are set. The mechanical simulation boundary conditions corresponding to the target cable model are set, and the electrothermal coupling simulation boundary conditions corresponding to the target cable model are set. According to the mechanical simulation boundary conditions and the target cable model, the first initial thickness is adjusted to obtain a first target thickness, and according to the electrothermal coupling simulation boundary conditions and the target cable model, the second initial thickness is adjusted to obtain a second target thickness. According to the first target thickness and the second target thickness, the metal sheath thickness interval corresponding to the target cable is determined. It can be seen that the embodiment of the present invention obtains the structural parameters, electrothermal parameters, and mechanical characteristic parameters of the cable to set the thickness of the metal sheath in a targeted manner. In addition, the finite element model is used to simulate the conditions under the mechanical simulation boundary conditions and the electrothermal coupling simulation boundary conditions, and the thickness range that meets the safety requirements and temperature requirements is obtained to determine the appropriate thickness of the metal sheath, thereby solving the technical problem in the related art that the determined thickness of the cable metal sheath is usually set to a fixed thickness, which is not targeted and difficult to adapt to environmental changes.

[0057] As an optional embodiment, the first initial thickness is adjusted according to the mechanical simulation boundary conditions and the target cable model to obtain the first target thickness, including: determining the safety factor distribution parameters obtained by simulating the target cable model under the mechanical simulation boundary conditions under the first initial thickness; when the safety factor distribution parameters do not exist within the first distribution parameter range, increasing the first initial thickness until the obtained safety factor distribution exists within the first distribution parameter range to obtain the first target thickness.

[0058] In this embodiment, the safety factor distribution parameters obtained by simulating the target cable model under the mechanical simulation boundary conditions under the first initial thickness are determined. When the safety factor distribution parameters do not exist within the first distribution parameter range, the first initial thickness is increased until the obtained safety factor distribution exists within the first distribution parameter range, thereby obtaining the first target thickness.

[0059] Among them, the mechanical simulation boundary conditions include various mechanical loads that the cable may bear, such as tension, bending, compression, vibration, etc., as well as the action mode, size and duration of these loads. Before starting the optimization process, it is necessary to set an initial thickness of the metal sheath (first initial thickness). Then, the target cable model is subjected to mechanical simulation under this initial thickness. The simulation will simulate the mechanical behavior of the cable in the actual working environment and output the safety factor distribution parameters, which reflect the safety margin of each part of the cable when it is subjected to mechanical loads. The safety factor distribution parameters obtained by simulating the target cable model under the mechanical simulation boundary conditions under the initial first initial thickness are determined. That is, the corresponding safety factor distribution parameters under this initial thickness are determined. The safety factor distribution parameters obtained by simulation are compared with the predetermined first distribution parameter range. This range is determined based on factors such as the design requirements, safety standards and expected mechanical loads of the cable, and can be customized according to actual applications and scenarios to ensure that the cable has sufficient safety margin when subjected to various mechanical loads. If the safety factor distribution parameters obtained by simulation do not meet the requirements of the first distribution parameter range (i.e., the safety factor is too low and there is a safety hazard), it is necessary to increase the initial thickness of the metal sheath (the first initial thickness) and re-run the simulation. This process will be repeated until a suitable metal sheath thickness (the first target thickness) is found so that the safety factor distribution parameters obtained by simulation can fall within the predetermined range.

[0060] It should be noted that when performing simulation operation, simulations under various working conditions can be performed to determine the safety factors under different conditions, and then obtain the above-mentioned safety factor distribution parameters. That is, by simulating the stress conditions of the cable under different working conditions, its behavior in actual applications can be predicted. Through its behavior, its safety factor is determined. The higher the safety factor, the safer the cable is at this thickness, and the lower the safety factor, the unsafe the safety factor is at this thickness. The first initial thickness (i.e., the preliminary design thickness of the metal sheath) is adjusted through the mechanical simulation boundary conditions and the target cable model to ultimately determine the first target thickness that meets specific safety requirements.

[0061] Optimizing the thickness of the metal sheath through mechanical simulation can ensure that the cable has sufficient safety margin when subjected to various mechanical loads, reducing the risk of safety accidents caused by structural failure. Reasonable metal sheath thickness helps to improve the overall mechanical properties of the cable, such as bending stiffness, tensile strength, etc., so that the cable can still maintain a good working condition under complex working conditions. Compared with traditional empirical design or trial and error methods, the optimization method based on mechanical simulation can find the optimal thickness of the metal sheath more quickly and accurately, improving design efficiency and accuracy.

[0062] As an optional embodiment, the second initial thickness is adjusted according to the electrothermal coupling simulation boundary conditions and the target cable model to obtain the second target thickness, including: determining the temperature field distribution parameters obtained by simulating the target cable model under the electrothermal coupling simulation boundary conditions under the second initial thickness; when the temperature field distribution parameters do not exist within the second distribution parameter range, reducing the second initial thickness until the obtained temperature field distribution parameters exist within the second distribution parameter range to obtain the second target thickness.

[0063] In this embodiment, the temperature field distribution parameters obtained by simulating the target cable model under the electrothermal coupling simulation boundary conditions under the second initial thickness are determined. When the temperature field distribution parameters do not exist within the second distribution parameter range, the second initial thickness is reduced until the obtained temperature field distribution parameters exist within the second distribution parameter range, thereby obtaining the second target thickness.

[0064] Among them, the electrothermal coupling simulation boundary conditions are involved, which include parameters such as the ambient temperature of the cable operation, heat dissipation conditions (such as natural convection, forced air cooling, etc.), and current load. These boundary conditions will directly affect the temperature field distribution of the cable model during the simulation. Before starting the iteration process, it is necessary to set an initial thickness of the metal sheath (the second initial thickness). Then, the electrothermal coupling simulation is performed on the target cable model under this initial thickness. The simulation will simulate the thermal behavior of the cable in the actual working environment and output temperature field distribution parameters, such as the maximum temperature, average temperature, temperature gradient, etc. The temperature field distribution parameters obtained by the simulation are compared with the predetermined second distribution parameter range. This range is determined based on factors such as the design requirements, safety standards, and operating life of the cable, and is intended to ensure that the temperature of the cable will not be too high during operation, thereby affecting its performance and safety. If the temperature field distribution parameters obtained by the simulation do not meet the requirements of the second distribution parameter range (that is, the temperature is too high or too low), it is necessary to reduce the initial thickness of the metal sheath (the second initial thickness) and re-run the simulation. This process will be repeated until a suitable metal sheath thickness (second target thickness) is found so that the temperature field distribution parameters obtained by simulation can fall within a predetermined range.

[0065] By optimizing the thickness of the metal sheath through electrothermal coupling simulation, it can be ensured that the temperature of the cable will not be too high during operation, thereby avoiding safety issues such as insulation aging and short circuit caused by overheating. Reasonable metal sheath thickness helps to reduce the temperature stress of the cable and reduce fatigue damage to the cable material caused by temperature fluctuations, thereby extending the overall service life of the cable. Compared with the traditional trial and error method, the iterative optimization method based on electrothermal coupling simulation can find the optimal thickness of the metal sheath more quickly and accurately, thereby improving design efficiency.

[0066] As an optional embodiment, mechanical simulation boundary conditions corresponding to the target cable model are set, and electrothermal coupling simulation boundary conditions corresponding to the target cable model are set, including: determining the downward pressure distance of the bending pressure head corresponding to the target cable model and the short-circuit capacity according to the scenario parameters applied by the target cable; setting the mechanical simulation boundary conditions corresponding to the target cable model according to the downward pressure distance, and setting the electrothermal coupling simulation boundary conditions corresponding to the target cable model according to the short-circuit capacity.

[0067] In this embodiment, the pressing distance of the bending pressure head corresponding to the target cable model and the short-circuit capacity are determined according to the scene parameters used by the target cable, so that the mechanical simulation boundary conditions corresponding to the target cable model are set according to the pressing distance, and the electrothermal coupling simulation boundary conditions corresponding to the target cable model are set according to the short-circuit capacity.

[0068] Among them, the downward pressing distance of the bending pressure head reflects the degree of bending that the cable may suffer in actual application. Different application scenarios (such as cable trays, tunnel laying, underground pipelines, etc.) have different bending requirements for cables, so the appropriate downward pressing distance needs to be determined according to the specific scenario.

[0069] Among them, the short-circuit capacity reflects the maximum current value that the cable can withstand when a short-circuit fault occurs. This parameter is crucial for evaluating the performance of cables under extreme electrical conditions because it directly affects the thermal stability and mechanical strength of the cable's insulation layer, conductor, and metal sheath.

[0070] According to the determined bending head pressing distance, corresponding boundary conditions can be set in the mechanical simulation, such as applying bending loads, constraints, etc. These boundary conditions will simulate the bending deformation and stress distribution that the cable may suffer in actual applications, thereby evaluating its mechanical properties and structural safety.

[0071] According to the determined short-circuit capacity, the corresponding boundary conditions can be set in the electrothermal coupling simulation. For example, in the simulation, it is necessary to set the electrical parameters corresponding to the short-circuit capacity (such as short-circuit current, duration, etc.) and the corresponding thermal boundary conditions (such as ambient temperature, heat dissipation conditions, etc.). These parameters will work together on the cable model to simulate its electrothermal behavior under short-circuit faults and evaluate the thermal stability and electrical performance of its insulation layer, conductor and metal sheath.

[0072] By setting the simulation boundary conditions according to the scenario parameters applied to the target cable, it can be ensured that the simulation results are closer to the actual situation, which helps to improve the accuracy and reliability of the simulation.

[0073] As an optional embodiment, the bending pressure head pressing distance corresponding to the target cable model is determined based on the scene parameters applied by the target cable, including: determining the bending radius corresponding to the target cable model, the distance between the first support and the second support in the target cable model, the support radius, the pressure head radius, and the nominal outer diameter of the target cable; determining the bending pressure head pressing distance based on the bending radius, distance, support radius, pressure head radius and nominal outer diameter of the cable.

[0074] In this embodiment, multiple parameters are determined, and based on these multiple parameters, the downward pressing distance of the bending pressure head is determined. Among them, the bending radius is involved, which is the maximum distance from the central axis of the cable to the inner edge of the bend during the bending process. The size of the bending radius directly affects the stress and strain distribution of the cable when it is bent. Among them, the distance between the first support and the second support is involved. In mechanical simulation, in order to simulate the bending of the cable, two supports (or support points) are usually required, and the distance between them determines the length of the bending section of the cable. Among them, the support radius is involved, that is, the radius of the contact part between the support and the cable, which may affect the local stress and strain distribution of the cable at the support. Among them, the pressure head radius is also involved. In mechanical simulation, the pressure head is used to simulate the device for applying bending load to the cable, and its radius is also an important factor affecting the simulation results. Among them, the nominal outer diameter of the cable is also involved. The nominal outer diameter of the cable is a basic parameter in cable design, which determines the overall size and shape of the cable.

[0075] After determining the above key parameters, these parameters need to be used to calculate the downward pressure distance of the bending head. The downward pressure distance of the bending head needs to ensure that the cable can be bent according to the predetermined bending radius during the simulation process, while avoiding excessive stress concentration or damage. By accurately calculating the downward pressure distance of the bending head, it can be ensured that the cable model in the mechanical simulation is closer to the actual use. This helps to improve the accuracy and reliability of the simulation results. Accurate bending head downward pressure distance can help better understand the mechanical behavior of the cable during the bending process, thereby optimizing the structural design of the cable.

[0076] As an optional embodiment, the short-circuit capacity is determined based on the scenario parameters used by the target cable, including: based on the benchmark capacity, benchmark voltage, short-circuit capacity, the per-unit reactance value and the per-unit resistance value between the target cable and the upstream transformer, and the per-unit impedance value of the system in which the target cable is located; the short-circuit capacity is determined based on the benchmark capacity, benchmark voltage, short-circuit capacity, per-unit impedance value, per-unit reactance value and per-unit resistance value.

[0077] In this embodiment, multiple parameters are determined, and the short-circuit bearing capacity is determined based on these multiple parameters. Among them, the reference capacity is involved, which is a basic capacity unit in the power system, used to normalize various parameters of the system, which is convenient for calculation and analysis. Among them, the reference voltage is involved, which is a reference voltage. Among them, the short-circuit capacity is involved, which refers to the ratio of the effective value of the short-circuit current at the specified short-circuit point of the power system when a three-phase metallic short circuit occurs. It reflects the ability of the system to provide short-circuit current to the short-circuit point. Among them, the reactance per unit value and the resistance per unit value are involved, which respectively represent the reactance and resistance per unit values ​​between the target cable and the upper transformer, and the various parts of the system. It reflects the obstruction of the cable and system components to the flow of current during a short circuit. Among them, the system impedance per unit value is involved, which is a comprehensive reflection of the impedance per unit value of each component of the system. On the basis of the known above parameters, the short-circuit current that the target cable can actually withstand in a short-circuit fault can be determined by complex power system calculations. The calculation of short-circuit current needs to consider the system topology, the impedance characteristics of each component, the location of the short-circuit point, etc. By comprehensively considering these factors, the maximum current carrying capacity of the target cable in a short-circuit fault, that is, the short-circuit capacity, can be obtained.

[0078] Accurately determining the short-circuit capacity of the target cable can ensure that the cable will not be damaged due to excessive current in the event of a sudden short-circuit fault, thereby improving the accuracy and reliability of the electrical design. As an important component of the power system, the ability of the cable to withstand short-circuit capacity directly affects the stability and safety of the entire system. Through reasonable calculation and design, it can be ensured that the cable can withstand sufficient current impact in a short-circuit fault, avoiding system collapse or large-scale power outages.

[0079] As an optional embodiment, after determining the metal sheath thickness range corresponding to the target cable based on the first target thickness and the second target thickness, it also includes: setting the thickness of the metal sheath in the target cable to a thickness value in the metal sheath thickness range to obtain an implementation cable, so that the implementation cable is used to implement power transmission.

[0080] In this embodiment, a specific thickness value is selected as the actual thickness of the metal sheath. This selection process may be affected by other auxiliary reference factors, such as cost considerations, manufacturing process limitations, performance optimization requirements, etc. By comprehensively considering these factors, it can be ensured that the selected thickness value is within the performance requirements of the cable safety and meets the requirements of economy or other performance. After determining the specific thickness of the metal sheath, the implementation cable can be manufactured according to this parameter. This includes selecting suitable conductor materials, insulating materials, fillers and sheath materials, etc., and processing and manufacturing according to the established production process. The final implementation cable will have a predetermined metal sheath thickness and other related performance parameters.

[0081] The completed implementation cable will be used in the power transmission system to transmit electric energy. Since the thickness of its metal sheath is carefully designed and selected, it can ensure that the cable has good mechanical protection, electrical insulation and corrosion resistance during the transmission process, thereby ensuring the safety and reliability of power transmission.

[0082] Based on the above embodiments and optional embodiments, an optional implementation is provided, which is described in detail below.

[0083] As the problem of buffer layer ablation of corrugated aluminum high-voltage cables becomes increasingly prominent, an optional implementation of the present invention proposes a new cable structure to fundamentally change the problem of buffer layer ablation, which becomes a solution to buffer layer ablation. An optional implementation of the present invention uses a smooth aluminum sheathed cable as a new type of structural cable. Since the aluminum sheath has no protrusions and can make good contact with the buffer layer, the problem of buffer layer ablation can be fundamentally suppressed. On the one hand, the metal sheath of the smooth aluminum sheathed cable serves as a loop for short-circuit current; on the other hand, it serves to maintain the bending performance of the cable. However, there are no clear regulations on the determination of the thickness of the metal sheath of the smooth aluminum sheathed cable. Therefore, an optional implementation of the present invention proposes a method for determining the metal sheath of a high-voltage smooth aluminum sheathed cable, so as to calculate a reference range for the thickness of the metal sheath of the smooth aluminum sheathed cable under the voltage level and interface.

[0084] That is, an optional embodiment of the present invention provides a method for calculating the reference range of the metal sheath thickness of smooth aluminum sheathed cables for various voltage levels and interfaces based on finite element simulation. On the one hand, when the thickness of the metal sheath of the smooth aluminum sheathed cable increases, the bending radius of the smooth aluminum sheathed cable increases, and the construction difficulty increases; on the other hand, when the thickness of the metal sheath decreases, the resistance per unit length of the metal sheath increases, and when the same short-circuit capacity flows through, the heat generated by the metal sheath per unit length increases, affecting the performance of the outer sheath and the hot melt adhesive. Figure 2 A method flow chart of a method for providing an optional embodiment of the present invention, Figure 3 A schematic diagram of the structure of a smooth aluminum sheathed cable provided in an optional embodiment of the present invention, Figure 4 A schematic diagram of calculating the pressing distance of the indenter using the three-point bending method provided in an optional embodiment of the present invention, Figure 5 A schematic diagram of the safety factor distribution of the three-layer composite structure of aluminum sheath-hot melt adhesive-outer sheath of a smooth aluminum sheathed cable provided in an optional embodiment of the present invention, Figure 6 A schematic diagram of the thickness of each layer of the cable provided in an optional embodiment of the present invention, such as Figure 2 , 3 , 4, 5, and 6, the optional implementation modes of the present invention are introduced below:

[0085] The technical solution adopted in the optional implementation mode of the present invention generally has the following process: first, the initial thickness of the metal sheath of the smooth aluminum sheath cable to be calculated is set, and then a mechanical simulation is performed on the smooth aluminum sheath cable, and then the thickness of the metal sheath is modified according to the result, and the simulation steps are repeated until the thickness of the metal sheath that meets the bending test conditions is calculated as the maximum value of the thickness of the metal sheath. Similarly, an electric-thermal coupling simulation is performed on the smooth aluminum sheath cable according to the initial thickness of the metal sheath, and then the thickness of the metal sheath is modified according to the result, and the simulation steps are repeated until the thickness of the metal sheath that meets the short-circuit capacity is calculated as the minimum value of the thickness of the metal sheath. The above steps are combined to obtain a reference range for the thickness of the smooth aluminum sheath metal sheath.

[0086] The method provided in an optional embodiment of the present invention comprises the following steps:

[0087] A. Collect relevant parameters of cable materials and structures, and complete finite element simulation modeling of cables;

[0088] B. Calculate the pressing distance of the pressure head in the three-point bending method according to the bending radius of the smooth aluminum sheathed cable bending test;

[0089] C. Determine the short-circuit capacity that the metal sheath of the smooth aluminum sheathed cable needs to bear based on the line where the cable is located;

[0090] D. Adjust the boundary conditions of the finite element model of mechanical simulation and perform a force analysis on the bending of the cable under the working conditions described in process B;

[0091] E. Adjust the boundary conditions of the finite element model for the electric-thermal coupling field simulation and analyze the thermal field of the cable under the working conditions described in process C.

[0092] The step A comprises the following steps:

[0093] A1. Collect the structural parameters of the cable to be calculated except the metal sheath. Collect the outer radius r of the conductor c , conductor shield, XLPE insulation and insulation shield three-layer composite structure outer radius r x , buffer layer outer radius r b , hot melt adhesive thickness hh 、Outer sheath outer radius h p , Set the parameters to be determined: smooth aluminum sleeve, aluminum sleeve outer radius r s2 ;

[0094] A2. According to the cable parameters to be simulated, determine the mechanical characteristic parameters required for each layer simulation. Collect the XLPE Young's modulus E i , Poisson's ratio μ i , shaping parameters; Cable aluminum sheath aluminum material Young's modulus E s , Poisson's ratio μ s , shaping parameters; hot melt adhesive tensile modulus Rm h , shear modulus G h , Shear Strength Breaking energy; Young's modulus E required for outer sheath p , Poisson's ratio μ p , shaping parameters;

[0095] A3. According to the cable parameters to be simulated, determine the electrical and thermal parameters required for each layer simulation. Collect the relative dielectric constant ε, conductivity γ, thermal conductivity k, constant pressure heat capacity c, and density ρ parameters of the conductor, conductor shield, XLPE insulation and insulation shield three-layer composite structure, buffer layer, metal sheath, and outer sheath;

[0096] A4. Establish the corresponding cable simulation model according to the simulation parameters.

[0097] The step B comprises the following steps:

[0098] B1. Determine the cable model length l c And the distance l between the supports in the simulation s , where the distance between the pressure head and the two supports should be equal, and l c >1.1l s , that is, to ensure that there is a certain margin when the cable is bent.

[0099] B2. Investigate the bending radius of the smooth aluminum sheathed cable during the test and determine the actual bending radius r of the cable g .

[0100] B3. Determine the downward pressure distance l of the bending pressure head according to the actual bending radius of the cable. x .

[0101] The step C comprises the following steps:

[0102] C1. Investigate the impedance per unit value Z of the system where the smooth aluminum sheathed cable is located * , the resistance value R of the line between the cable and the upper transformer L* And reactance per unit value X L* , Base capacity S b , short circuit capacity Sk , Reference cable U b , short-circuit current removal time t;

[0103] C2. Calculate the short-circuit current that the cable can withstand based on the parameters in C1 and determine the short-circuit capacity of the cable to be I / t;

[0104] The step D specifically comprises the following steps:

[0105] D1. Set the corresponding boundary conditions and interaction parameters in the mechanical simulation model to complete the cable finite element modeling;

[0106] D2. Determine the maximum value of the metal sheath thickness of the smooth aluminum sheathed cable based on the results.

[0107] The step E comprises the following steps:

[0108] E1. Set the corresponding boundary conditions and interaction parameters in the electrical-thermal coupling simulation model to complete the cable finite element modeling;

[0109] E2. Determine the minimum thickness of the metal sheath of the smooth aluminum sheathed cable based on the results.

[0110] Specifically, the method provided by the present invention comprises the following steps:

[0111] Step 1: Collect relevant parameters of cable materials and structures, and complete finite element simulation modeling of the cable.

[0112] Step 1.1: Collect the structural model parameters of the cable to be calculated and the outer radius r of the conductor c , conductor shield, XLPE insulation and insulation shield three-layer composite structure outer radius r x , buffer layer outer radius r b , hot melt adhesive thickness h h 、Outer sheath outer radius h p , Set the parameters to be determined: smooth aluminum sleeve, aluminum sleeve outer radius r s The initial value of

[0113] Table 1 is a parameter table of the smooth aluminum sheath structure cable used in the example of this method, as shown in Table 1:

[0114] Table 1

[0115] Serial number structure Thickness / mm Outer diameter / mm 1 conductor — 36 2 Conductor shielding 1 38 3 XLPE insulation 16 70 4 Insulation shielding 1 72 5 Buffer layer 2 76 6 Smooth aluminum sheath <![CDATA[r s -38]]> <![CDATA[2r s ]]> 7 Hot melt adhesive layer 0.2 <![CDATA[2r s +0.4]]> 8 Outer sheath 5 <![CDATA[2r s +10.4]]>

[0116] Step 1.2: Collect or measure the mechanical characteristic parameters of each layer of the cable to be built. Since the bending performance of the cable mainly depends on the aluminum sheath and its external structure, the conductor shield, XLPE and insulation shield structure are all equivalent to the XLPE structure. Therefore, it is only necessary to collect the Young's modulus, Poisson's ratio and shaping parameters of the cross-linked polyethylene; the Young's modulus, Poisson's ratio and shaping parameters of the aluminum sheath; collect the tensile modulus, shear modulus, fracture energy and shear strength related parameters of the hot melt adhesive; collect the Young's modulus, Poisson's ratio and shaping parameters of the outer sheath.

[0117] Table 2 is a mechanical parameter table of the smooth aluminum sheathed cable used in an optional embodiment of the present invention, and Table 3 is a mechanical parameter table of the hot melt adhesive in an optional embodiment of the present invention. The parameters collected in this example are shown in Tables 2 and 3:

[0118] Table 2

[0119]

[0120] Table 3

[0121] Tensile modulus / MPa 58.4 Shear modulus / MPa 20.9 Peel strength / (N / mm) 2.35 Shear strength / MPa 1.93

[0122] Step 1.3: Collect or measure the electrical and thermal parameters of each layer of the cable to determine the electrical and thermal parameters required for the simulation of each layer. Collect the relative dielectric constant, electrical conductivity, thermal conductivity, constant pressure heat capacity, and density parameters of the conductor, conductor shield, XLPE insulation and insulation shield three-layer composite structure, buffer layer, metal sheath, and outer sheath. Table 4 is a table of electrical and thermal parameters of the smooth aluminum sheathed cable used in the optional implementation of the present invention, as shown in Table 4;

[0123] Table 4

[0124]

[0125] Step 2: Calculate the downward pressure distance of the pressure head in the simulation calculation according to the actual bending condition of the cable.

[0126] Step 2.1: Investigate the bending radius used in the cable bending test R = 25 (D + d) + 5%, where D is the nominal outer diameter of the cable and d is the nominal diameter of the conductor, in mm;

[0127] Step 2.2: Calculate the cable pressure head downward distance l in the simulation x In the three-point bending test, the distance between the indenter and the two supports is equal, and the radius of the support and the indenter is r Z , calculate the cable pressure head downward distance l according to the following formula x ,like Figure 4 As shown:

[0128]

[0129] Step 3: Calculate the short-circuit capacity of the cable based on the short-circuit parameters of the system in which the smooth aluminum sheathed cable is located.

[0130] Step 3.1: Investigate the impedance per unit value Z of the system where the smooth aluminum sheathed cable is located k , the resistance value R of the line between the cable and the upper transformer L* And reactance per unit value X L* , Base capacity S b , short circuit capacity S k , Reference cable U b , short-circuit current removal time t;

[0131] Step 3.2: Calculate the current amplitude I of the short-circuit capacity of the cable according to the following formula, and determine the short-circuit capacity calculated by the electric-thermal coupling field of the cable as I / t;

[0132]

[0133] Step 4: Determine the maximum thickness of the aluminum sheath through mechanical simulation;

[0134] Step 4.1: Set the boundaries in the mechanical simulation analysis. Set fixed constraints for the lower pressure head and displacement constraints for the upper pressure head. Only adjust the Z-axis direction constraints, and set the constraints in other directions to 0. Set the cable axial section to symmetric constraints. Set the hot melt adhesive layer and the aluminum sheath and outer sheath as binding constraints, and set the friction coefficient for the other contacts;

[0135] Step 4.2: According to the safety factor distribution of the three-layer composite structure of aluminum sheath-hot melt adhesive-outer sheath in the calculation results, increase the thickness of the metal sheath until the smooth aluminum sheath cable meets the requirements of the bending test.

[0136] Step 5: Determine the minimum thickness of the aluminum sheath through electrical-thermal coupling simulation;

[0137] Step 5.1: Set the boundaries and excitations in the electro-thermal coupling simulation analysis. Set the conductor as the terminal-voltage boundary, the aluminum sheath terminal-ground boundary and the short-circuit capacity excitation, and use the conductor and aluminum sheath together as generalized heat sources. Ignore the axial heat transfer of the cable, and set the outer sheath boundary to convection heat flux;

[0138] Step 5.2: Based on the maximum temperature that the outer sheath and hot melt adhesive can withstand, and under the calculated short-circuit capacity of the cable, reduce the thickness of the metal sheath until the temperature distribution of the smooth aluminum sheath cable meets the requirements.

[0139] Through the above optional implementation, at least the following beneficial effects can be achieved:

[0140] (1) It is possible to calculate the thickness of the metal sheath of smooth aluminum sheath cables. By calculating the mechanical and short-circuit capacity of smooth aluminum sheath cables with different metal sheath thicknesses, the reference range of the thickness of the smooth aluminum sheath is determined.

[0141] (2) It is possible to analyze smooth aluminum sheathed cables of different voltage levels and cross-sections by changing the cable parameters such as the thickness of each layer and mechanical parameters. This method has a certain degree of universality and is applicable to various smooth aluminum sheathed cables.

[0142] It should be noted that, for the above-mentioned method embodiments, for the sake of simplicity, they are all described as a series of action combinations, but those skilled in the art should know that the present invention is not limited by the described action sequence, because according to the present invention, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present invention.

[0143] Through the description of the above implementation methods, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods of various embodiments of the present invention.

[0144] Example 2

[0145] According to an embodiment of the present invention, there is also provided a device for implementing the above-mentioned method for determining the thickness of the metal sheath of the cable. Figure 7 : is a structural block diagram of a device for determining the thickness of a metal sheath of a cable according to an embodiment of the present invention. Figure 7 As shown, the device includes: an acquisition module 702, a first determination module 704, a construction module 706, a setting module 708, an adjustment module 710 and a second determination module 712. The device is described in detail below.

[0146] An acquisition module 702 is used to acquire a target cable, wherein the target cable at least includes a metal sheath;

[0147] A first determination module 704, connected to the acquisition module 702, is used to determine the cable parameters of the target cable, wherein the cable parameters include: structural parameters, electrothermal parameters, and mechanical characteristic parameters;

[0148] A construction module 706, connected to the first determination module 704, is used to construct a target cable model for finite element simulation according to the cable parameters, and to set a first initial thickness and a second initial thickness of the metal sheath;

[0149] A setting module 708, connected to the construction module 706, is used to set mechanical simulation boundary conditions corresponding to the target cable model and to set electrothermal coupling simulation boundary conditions corresponding to the target cable model;

[0150] The adjustment module 710 is connected to the setting module 708, and is used to adjust the first initial thickness according to the mechanical simulation boundary conditions and the target cable model to obtain the first target thickness, and to adjust the second initial thickness according to the electrothermal coupling simulation boundary conditions and the target cable model to obtain the second target thickness;

[0151] The second determination module 712 is connected to the adjustment module 710 and is used to determine a metal sheath thickness interval corresponding to the target cable according to the first target thickness and the second target thickness.

[0152] It should be noted here that the above-mentioned acquisition module 702, first determination module 704, construction module 706, setting module 708, adjustment module 710 and second determination module 712 correspond to steps S102 to S112 in the method for determining the thickness of the metal sheath of the cable, and the examples and application scenarios implemented by the multiple modules are the same as the corresponding steps, but are not limited to the contents disclosed in the above-mentioned embodiment 1.

[0153] Example 3

[0154] According to another aspect of an embodiment of the present invention, there is also provided an electronic device, comprising: a processor; and a memory for storing instructions executable by the processor, wherein the processor is configured to execute instructions to implement any of the above methods for determining the thickness of a metal sheath of a cable.

[0155] Example 4

[0156] According to another aspect of an embodiment of the present invention, a computer-readable storage medium is provided. When instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device can execute any of the above-mentioned methods for determining the metal sheath thickness of a cable.

[0157] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0158] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0159] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0160] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0161] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0162] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0163] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for determining the thickness of a metal sheath of a cable, characterized in that: include: Acquire a target cable, wherein the target cable at least includes a metal sheath; Determining cable parameters of the target cable, wherein the cable parameters include: structural parameters, electrothermal parameters, and mechanical characteristic parameters; According to the cable parameters, a target cable model of finite element simulation is constructed, and a first initial thickness and a second initial thickness of the metal sheath are set; Setting mechanical simulation boundary conditions corresponding to the target cable model, and setting electrothermal coupling simulation boundary conditions corresponding to the target cable model; According to the mechanical simulation boundary conditions and the target cable model, the first initial thickness is adjusted to obtain a first target thickness, and according to the electrothermal coupling simulation boundary conditions and the target cable model, the second initial thickness is adjusted to obtain a second target thickness; A metal sheath thickness interval corresponding to the target cable is determined according to the first target thickness and the second target thickness.

2. The method according to claim 1, characterized in that According to the mechanical simulation boundary condition and the target cable model, the first initial thickness is adjusted to obtain a first target thickness, including: Determine the safety factor distribution parameters obtained by simulating the target cable model under the mechanical simulation boundary conditions under the first initial thickness; In the case that the safety factor distribution parameter does not exist within the first distribution parameter range, the first initial thickness is increased until the obtained safety factor distribution exists within the first distribution parameter range, thereby obtaining the first target thickness.

3. The method according to claim 1, characterized in that According to the electrothermal coupling simulation boundary condition and the target cable model, the second initial thickness is adjusted to obtain a second target thickness, including: Determine temperature field distribution parameters obtained by simulating a target cable model under the electrothermal coupling simulation boundary condition under the second initial thickness; When the temperature field distribution parameter does not exist within the second distribution parameter range, the second initial thickness is reduced until the obtained temperature field distribution parameter exists within the second distribution parameter range, thereby obtaining the second target thickness.

4. The method according to claim 1, characterized in that: Setting a mechanical simulation boundary condition corresponding to the target cable model and setting an electrothermal coupling simulation boundary condition corresponding to the target cable model include: Determining the downward pressing distance of the bending pressure head corresponding to the target cable model and the short-circuit bearing capacity according to the scenario parameters applied by the target cable; According to the depression distance, a mechanical simulation boundary condition corresponding to the target cable model is set, and according to the short-circuit bearing capacity, an electrothermal coupling simulation boundary condition corresponding to the target cable model is set.

5. The method according to claim 4, characterized in that Determining a bending pressure head downward pressure distance corresponding to the target cable model according to the scene parameters applied by the target cable includes: Determining a bending radius corresponding to the target cable model, a distance between a first support and a second support in the target cable model, a support radius, a pressure head radius, and a nominal outer diameter of the target cable; The pressing distance of the bending pressure head is determined according to the bending radius, the distance, the support radius, the pressure head radius and the nominal outer diameter of the cable.

6. The method according to claim 4, characterized in that According to the scenario parameters of the target cable, the short-circuit capacity is determined, including: Based on the reference capacity, reference voltage, short-circuit capacity of the target cable, the per-unit reactance value and per-unit resistance value between the target cable and the upper transformer, and the per-unit impedance value of the system in which the target cable is located; The short-circuit withstand capacity is determined based on the reference capacity, the reference voltage, the short-circuit capacity, the impedance per unit value, the reactance per unit value and the resistance per unit value.

7. The method according to any one of claims 1 to 6, characterized in that: After determining the metal sheath thickness interval corresponding to the target cable according to the first target thickness and the second target thickness, the method further includes: The thickness of the metal sheath in the target cable is set to a thickness value in the metal sheath thickness range to obtain an implementation cable, so that the implementation cable is used to implement power transmission.

8. A device for determining the thickness of a cable metal sheath, characterized in that: include: An acquisition module, used for acquiring a target cable, wherein the target cable at least comprises a metal sheath; A first determination module is used to determine the cable parameters of the target cable, wherein the cable parameters include: structural parameters, electrothermal parameters, and mechanical characteristic parameters; A construction module, used to construct a target cable model for finite element simulation according to the cable parameters, and set a first initial thickness and a second initial thickness of the metal sheath; A setting module, used to set mechanical simulation boundary conditions corresponding to the target cable model, and to set electrothermal coupling simulation boundary conditions corresponding to the target cable model; an adjustment module, configured to adjust the first initial thickness according to the mechanical simulation boundary condition and the target cable model to obtain a first target thickness, and to adjust the second initial thickness according to the electrothermal coupling simulation boundary condition and the target cable model to obtain a second target thickness; The second determination module is used to determine the metal sheath thickness interval corresponding to the target cable according to the first target thickness and the second target thickness.

9. An electronic device, characterized in that: include: processor; a memory for storing instructions executable by the processor; The processor is configured to execute the instructions to implement the method for determining the thickness of the metal sheath of a cable as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: When the instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device is enabled to execute the method for determining the thickness of the metal sheath of a cable as claimed in any one of claims 1 to 7.

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