Model establishment and characteristic analysis method and device of composite superconducting energy transmission system, medium and equipment

Abstract

The invention discloses a model establishment and characteristic analysis method of a composite superconducting energy conveying system. The method comprises the following steps: S100, establishing an electromagnetic thermal coupling model of the composite superconducting energy conveying system; s200, setting a physical field of the electromagnetic thermal coupling model of the composite superconducting energy transmission system; s300, analyzing the operation characteristics of the composite superconducting energy transmission system by adopting a finite element method, and evaluating the electromagnetic thermal coupling characteristics of the composite superconducting energy transmission system under the multi-physical field coupling effect; and S400, carrying out optimization design on the winding angle and the winding direction of the superconducting tape by adopting a hybrid algorithm based on particle swarm optimization and artificial bee colony optimization so as to improve the current distribution uniformity and the current-carrying capacity of the system. The problems of heat leakage and current sharing in multi-energy cooperative transmission are solved, the current-carrying capacity and stability of the system are improved, the system is suitable for long-distance and large-capacity hydrogen energy and electric power integrated transmission, and technical support is provided for energy internet construction.

Description

Technical Field

[0001] This invention belongs to the field of energy transmission technology, and more specifically, it relates to a method for model establishment and characteristic analysis of a composite superconducting energy transmission system. Background Technology

[0002] With the rapid development of the economy and industry, the demand for energy is increasing day by day. However, the places where energy is consumed and the places where it is produced are often far apart, resulting in an imbalance between supply and demand. This makes long-distance energy transmission an urgent problem to be solved.

[0003] my country's load centers and energy distribution are uneven, mainly exhibiting a pattern of "north-south mutual supply" and "west-to-east power transmission." Although my country has vigorously promoted clean energy power generation such as photovoltaic, wind, and nuclear power, large-scale photovoltaic power plants, wind power plants, and nuclear power plants are still located in remote areas. The coal needed for thermal power generation in my country is mainly distributed in North China and Northwest China, while hydropower is mainly concentrated in Southwest China. Load centers are mainly concentrated in Central and Eastern China, and it is projected that by 2050, this proportion will reach 75% of the country's electricity consumption. In addition, with the continuous improvement of people's living standards, the demand for electricity is increasing. According to the International Energy Agency, it is projected that by 2050, global electricity demand will increase by 40%, and transmission losses have always been a significant problem in the power system.

[0004] Hydrogen is the most ideal energy alternative, which can be converted from solar energy, nuclear energy, natural gas, and other methods, and can also be produced by water electrolysis. However, the energy sources for hydrogen production are often located far away. The heat released by hydrogen combustion is about three times that of petroleum. Combined with oxygen, it can be used in fuel cells. The byproduct of hydrogen combustion is water, resulting in zero environmental pollution. Therefore, countries around the world are actively researching hydrogen energy technology. Hydrogen accounts for about 10% of my country's final energy consumption, and this percentage is expected to continue to grow with advancements in hydrogen energy technology. However, current hydrogen storage and transportation technologies still require breakthroughs. Transporting gaseous hydrogen via pipelines or other means of transportation is inefficient, while transporting liquid hydrogen by train, car, or ship cannot meet the fast, continuous, and ever-increasing energy demands. Pipeline transport of liquid hydrogen inevitably leads to heat leakage, causing vaporization and creating high-pressure safety hazards. Therefore, conventional liquid hydrogen pipelines are limited to short-distance transport and are unsuitable for long-distance hydrogen energy transmission.

[0005] In response to the aforementioned power and energy transmission issues, relevant research institutions have begun exploring new forms of energy transmission that combine power transmission with clean energy. Whether it's upgrading or constructing new pipelines or reconfiguring power transmission cables, the integrated transmission of electrical and clean energy will be a potential technological means and mode of energy transmission in the future. The development of superconducting power technology has provided new opportunities and solutions for solving power transmission problems. Compared to conventional cables, superconducting cables exhibit significant advantages in transmission capacity, transmission loss, transmission line laying, voltage levels, and safety.

[0006] Superconducting power transmission will be a revolutionary technology to break through the bottleneck of power transmission, fundamentally solving the problems of long distance, large capacity, and transmission loss faced by current power transmission systems. However, superconducting power transmission requires a certain low-temperature operating environment. Liquefied natural gas (LNG) can be cooled to around 90K using a mixed working fluid cryogenic refrigeration technology, making it suitable as a coolant for first-generation superconducting cable (BSCCO). LNG also compresses natural gas by approximately 600 times during transmission, resulting in higher transmission capacity and stronger safety performance. Liquid hydrogen (LH2), as an ideal clean energy source with zero pollution, has a liquefaction temperature of approximately 17K, meeting the temperature requirements of superconducting cable coolants. Therefore, the rational design of transmission pipelines for superconducting cables and LNG / hydrogen energy will help solve energy transmission problems. However, both single-liquid-hydrogen and single-liquid-natural-gas superconducting energy transmission systems face the challenges of re-laying another energy transmission system and heat leakage issues. Summary of the Invention

[0007] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention provides a model establishment and characteristic analysis method for a composite superconducting energy transmission system, aiming to achieve efficient, high-capacity, and long-distance transmission of multiple energy sources. This effectively improves the current situation where energy transmission is constrained, conforms to the development trend of large-scale energy gathering and transmission, and provides an advanced technical solution for the future construction of the energy internet and the new landscape of energy transmission. It has significant research significance and application potential.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for model establishment and characteristic analysis of a composite superconducting energy transmission system, comprising the following steps: S100. Establish an electromagnetic-thermal coupling model for the composite superconducting energy transmission system; S200. Set up the physical field for the electromagnetic thermal coupling model of the composite superconducting energy transmission system; S300. Based on the electromagnetic thermal coupling model after the physical field settings, the finite element method is used to analyze the operating characteristics of the composite superconducting energy transmission system and evaluate its electromagnetic thermal coupling characteristics under the action of multi-physical field coupling. S400 employs a hybrid algorithm based on particle swarm optimization and artificial bee colony optimization to optimize the winding angle and winding direction of the superconducting tape, thereby improving the uniformity of current distribution and the system's current carrying capacity.

[0009] Preferably, the composite superconducting energy transmission system includes a first liquid hydrogen transmission pipeline, a first superconducting layer, a first electrical insulation layer, a second superconducting layer, a second liquid hydrogen transmission pipeline, a first thermal insulation layer, a liquefied natural gas transmission pipeline, a second electrical insulation layer, a superconducting shielding layer, and a second thermal insulation layer arranged coaxially from the inside out, wherein the first superconducting layer and the second superconducting layer are wound from superconducting tape YBCO.

[0010] Preferably, step S100 specifically includes the following steps: S101. Construct a two-dimensional axisymmetric geometric model of the composite superconducting energy transmission system; S102. Mesh the two-dimensional axisymmetric geometric model, where the pipe part is meshed using a mapped mesh and the air domain is meshed using a free triangular mesh. S103. Define the boundary conditions for the two-dimensional axisymmetric geometric model. Let the central axis of the pipe be the inner side, the radial direction outward be the outer side, the side closer to the two superconducting layers be the inner boundary, the side farther from the superconducting layers be the outer boundary, and the inlet and outlet of the pipe be the upper and lower boundaries.

[0011] Preferably, step S200 specifically includes the following steps: S201. Define the basic properties of the electromagnetic thermal coupling model, including the width, thickness, critical current density under zero field, and rated current of the superconducting tape; S202. Set the material properties of the superconducting tape, including relative permittivity, relative permeability, density, thermal conductivity, heat capacity, and resistivity; S203. Set the magnetic field boundary conditions, set the outer boundary of the air domain to 0, and apply current excitation to the superconducting layer by point-by-point constraint method; S204. Establish a solid heat transfer interface and set the power loss of the superconducting layer as the heat source; S205. Establish a multiphysics interface and add an electromagnetic thermal coupling interface and a temperature coupling interface.

[0012] Preferably, the electromagnetic thermal coupling characteristics include: ① Magnetic flux density distribution: The electrical insulation layer has the highest magnetic flux density, with an average magnetic flux of about 0.05 T, and the distribution is uniform. The magnetic flux density distribution shows that the inner boundary is larger and gradually decreases at the outer boundary. The magnetic field outside the shielding layer is close to 0. The magnetic flux density is basically uniform in the middle of the pipe, with a certain edge effect at the boundary. The magnetic flux density of other layers gradually decreases radially outward. ② Critical current density distribution: The critical current density is basically uniform and symmetrical in the inner and outer superconducting layers. The attenuation is greatest at the upper and lower boundaries of the superconducting layer, followed by the inner boundary, and the attenuation is smallest at the outer boundary. ③ Temperature distribution: The temperature of the insulation layer near the liquid hydrogen and liquefied natural gas pipelines is stable at about 17 K and 90 K respectively, and the insulation layer can effectively block heat exchange.

[0013] Preferably, in step S400, the hybrid optimization algorithm includes: The HTSPAB1 algorithm uses the optimal solution of the particle swarm optimization algorithm as the initial solution for the artificial bee colony algorithm for global search. The HTSPAB2 algorithm achieves optimal solution information exchange through the co-evolution of two populations: a particle swarm optimization algorithm with dynamic inertia weights and an artificial bee colony algorithm.

[0014] Preferably, in step S400, the optimization design of the winding angle and winding direction of the superconducting tape includes: ① Optimize variables The optimization variable for the superconducting layer is the orthorium angle. β and winding direction α Assume there are 2 superconducting layers. n There are several optimization variables, using optimization vectors. K Represented as:

[0015]

[0016] In the formula, β The orientation angle of the superconducting tape; α The winding direction of the superconducting tape is 1 or -1; P The distance between two adjacent layers of superconducting tape; the radius of the superconducting tape. r ; ② Optimization Objective The goal of superconducting layer current sharing design is to minimize the current difference between layers; therefore, the fitness function is expressed as:

[0017] In the formula, I i (K) and I j (K) represents the optimization vector. K Time i Layer and first j Current in the superconducting tape; m and n These are the number of superconducting tape layers and the number of superconducting tape strands, respectively. ③Constraints The current constraint condition for the superconducting layer optimization model is:

[0018] In the formula, I i It is the first i The actual current in the layered superconducting tape; N i It is the first i The number of strips in a layered superconducting tape; I c It is the average critical current of the superconducting tape; k 1. k 2 and k 3 are the critical current degradation coefficients considering electromagnetic, strain, and thermal cycling effects on the cable; k 4 represents the safety margin in the design.

[0019] Secondly, the present invention provides a model building and characteristic analysis device for a composite superconducting energy transmission system, comprising: The first processing unit is used to establish the electromagnetic thermal coupling model of the composite superconducting energy transmission system. The second processing unit is used to set the physical field of the electromagnetic thermal coupling model of the composite superconducting energy transmission system. The third processing unit is used to analyze the operating characteristics of the composite superconducting energy transmission system using the finite element method and evaluate its electromagnetic and thermal coupling characteristics under the action of multi-physics field coupling. The fourth processing unit is used to optimize the winding angle and winding direction of the superconducting tape using a hybrid algorithm based on particle swarm optimization and artificial bee colony optimization, so as to improve the uniformity of current distribution and the current carrying capacity of the system.

[0020] Thirdly, the present invention provides a computer-readable storage medium storing a computer program, which is executed by a processor to control the device where the processor is located to implement the steps of the model establishment and characteristic analysis device for the composite superconducting energy transmission system described in the first aspect of the present invention.

[0021] Fourthly, the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the model establishment and characteristic analysis device for the composite superconducting energy transmission system described in the first aspect of the present invention.

[0022] The present invention has the following advantages due to the adoption of the above technical solutions: 1. This invention addresses composite superconducting energy transmission systems, proposing corresponding model establishment and characteristic analysis methods for such systems. It establishes an overall electromagnetic-thermal coupling model of the composite superconducting energy transmission system and analyzes the characteristic distribution patterns. Based on the designed structure and parameters of the composite superconducting energy transmission system, a two-dimensional axisymmetric model of the overall pipeline's electromagnetic-thermal coupling is established, and detailed modeling and calculation methods are provided. The proposed composite superconducting energy transmission system with embedded liquefied natural gas significantly improves transmission performance. Furthermore, it demonstrates that maximizing the balance between the inner and outer sides of the pipeline and minimizing heat leakage contributes to improving the overall pipeline characteristics.

[0023] 2. This invention proposes a current-sharing optimization scheme for a composite superconducting energy transmission system and analyzes the optimization effect to solve the problem of uneven current distribution in superconducting cables or superconducting energy transmission systems caused by multi-layer superconducting tape stacking. The optimization effect is analyzed and evaluated: the proposed current-sharing optimization scheme for the composite superconducting energy transmission system improves the current distribution between superconducting conductor layers. A model of the superconducting layer is established based on the optimization parameters to verify the broad effectiveness of the proposed optimization scheme. The results show that when designing the current-sharing algorithm, attention should be paid to the information interaction between the iterative solution results and the initial values, which can help find the global optimal solution and improve the calculation speed, thus providing a technical basis for the comprehensive performance optimization and improvement of cryogenic composite energy transmission systems.

[0024] 3. This invention, by constructing a multiphysics simulation platform, achieves the coordinated prediction and evaluation of the electromagnetic, thermal, and mechanical characteristics of complex composite superconducting energy transmission systems, filling the technological gap in multiphysics coupling analysis tools in this field. The provided modeling methods and characteristic analysis processes can be widely applied to the structural optimization design, operational boundary condition determination, and system-level reliability assessment of composite superconducting cables, demonstrating significant engineering application value and industrialization prospects. Attached Figure Description

[0025] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. In the drawings: Figure 1 A flowchart illustrating the model establishment and characteristic analysis method for the composite superconducting energy transmission system provided by this invention; Figure 2 This is a schematic diagram of the superconducting layer parameters in this invention; Figure 3 This is a distribution diagram of the magnetic flux density and critical current density of the superconducting layer in this invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the present invention clearer, specific embodiments of the present invention will be further described below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0027] Accurate analysis of the operating characteristics of superconducting energy transmission systems is crucial for improving their current-carrying capacity and energy transmission performance, as well as optimizing their structure. Currently, the analysis of the operating characteristics of superconducting energy transmission systems is limited to single superconductors or individual superconducting layers. There is a lack of research that comprehensively considers other factors and the coupling between multiple physics fields. The operating characteristics of composite superconducting energy transmission systems are related to the overall structural arrangement, magnetic field, critical current, and temperature. Analyzing the electromagnetic or thermal properties of a single material in isolation can easily lead to deviations from reality. Therefore, this invention establishes a model of an overall composite superconducting energy transmission system. Using an electromagnetic-thermal coupling interface, a heat transfer model, and a multiphysics interface, it comprehensively simulates and analyzes the electromagnetic-thermal coupling characteristics, including the entire magnetic flux density distribution, temperature distribution, and critical current density distribution. Detailed characteristic distribution laws are solved, and the proposed composite superconducting energy transmission system is compared with a conventional superconducting energy transmission system to verify its advantages.

[0028] The following is a detailed description, with reference to the accompanying drawings, of a method and apparatus for model establishment and characteristic analysis of a composite superconducting energy transmission system provided by an embodiment of the present invention.

[0029] Example 1: Please see Figure 1 This invention is mainly aimed at a composite superconducting energy transmission system with a coaxial bipolar transmission structure. The composite superconducting energy transmission system includes a first liquid hydrogen transmission pipeline 1, a first superconducting layer 2, a first electrical insulation layer 3, a second superconducting layer 4, a second liquid hydrogen transmission pipeline 5, a first heat insulation layer 6, a liquefied natural gas transmission pipeline 7, a second electrical insulation layer 8, a superconducting shielding layer 9, and a second heat insulation layer 10 arranged coaxially from the inside to the outside. The first superconducting layer 2 and the second superconducting layer 4 are made of superconducting tape YBCO wound together.

[0030] The model establishment and characteristic analysis method for the composite superconducting energy transmission system provided in this embodiment includes the following steps: S100. Establish an electromagnetic-thermal coupling model for the composite superconducting energy transmission system, specifically as follows: S101. Construct a two-dimensional axisymmetric geometric model of the composite superconducting energy transmission system. Since the composite superconducting energy transmission system is completely symmetrical along the centerline, that is, a three-dimensional model of the composite superconducting energy transmission system can be obtained by rotating it 360° along the central axis of the pipeline. Therefore, studying the two-dimensional axisymmetric geometric model of the composite superconducting energy transmission system can reflect the overall characteristics inside the pipeline. S102. Mesh the two-dimensional axisymmetric geometric model, where the pipe part is meshed using a mapped mesh and the air domain is meshed using a free triangular mesh. S103. Define the boundary conditions for the two-dimensional axisymmetric geometric model. Let the central axis of the pipe be the inner side, the radial direction outward be the outer side, the side closer to the two superconducting layers be the inner boundary, the side farther from the superconducting layers be the outer boundary, and the inlet and outlet of the pipe be the upper and lower boundaries.

[0031] S200. Set up the physical field for the electromagnetic-thermal coupling model of the composite superconducting energy transmission system, specifically as follows: S201. Define the basic properties of the electromagnetic thermal coupling model, including the width, thickness, critical current density under zero field, and rated current of the superconducting tape (as shown in Table 1 below). Table 1. Basic properties of the composite superconducting energy transmission system model

[0032] S202. Set the material properties of the superconducting tape, including relative permittivity, relative permeability, density, thermal conductivity, heat capacity, and resistivity; S203. Set the magnetic field boundary conditions, set the outer boundary of the air domain to 0, and apply current excitation to the superconducting layer by point-by-point constraint method; S204. Establish a solid heat transfer interface and set the power loss of the superconducting layer as the heat source; S205. Establish a multiphysics interface and add an electromagnetic thermal coupling interface and a temperature coupling interface.

[0033] S300. Based on the electromagnetic-thermal coupling model after the physical field settings, the finite element method is used to analyze the operating characteristics of the composite superconducting energy transmission system and evaluate its electromagnetic-thermal coupling characteristics under the action of multi-physics coupling, including: ① Magnetic flux density distribution The composite superconducting energy transmission system exhibits certain AC ripple during operation in a real DC system. Its magnetic flux density distribution has the following characteristics: the magnetic flux density is highest in the electrical insulation layer, with an average flux of approximately 0.05 T, and is uniformly distributed, indicating a good achievement of the coaxial bipolar design effect, effectively counteracting the influence of the external magnetic field. The magnetic flux density distribution shows a larger distribution at the inner boundary and gradually decreases towards the outer boundary, with the magnetic field outside the shielding layer approaching zero. The magnetic flux density is basically uniformly distributed in the middle of the pipe, with some edge effect at the boundaries, while the magnetic flux density in other layers gradually decreases radially outward. Furthermore, there is almost no induced magnetic field outside the superconducting shielding layer, indicating that it provides good shielding. The magnetic flux density distribution also influences the temperature distribution and critical current density of the superconductor, suggesting a mutually coupled process. Therefore, a uniformly distributed magnetic flux is crucial for improving the characteristics of this energy transmission system.

[0034] ② Critical current density distribution Because the superconducting layer is designed as a coaxial bipolar two-layer superconducting tape YBCO, the superconducting shielding layer (BSCCO) has only a very small induced current. The critical current density is basically uniform and symmetrically distributed in the inner and outer superconducting layers. The attenuation is greatest at the upper and lower boundaries of the superconducting layer, followed by the inner boundary, and the attenuation is smallest at the outer boundary.

[0035] ③ Temperature distribution The temperature distribution within the pipe is uniform across all layers, with relatively small temperature rises. Liquid hydrogen serves as the refrigerant for the superconducting layer, while liquefied natural gas serves as the refrigerant for the superconducting shielding layer. The temperature rise is higher near the inner boundary of the liquid hydrogen layer, decreasing with radial distance from the superconducting layer. This is due to heat conduction from electrical losses within the superconducting layer. The temperature rise of the second liquid hydrogen layer (layer 5) is slightly lower than that of the first liquid hydrogen layer (layer 1). The temperature distribution of the two superconducting layers shows a slightly higher temperature at the inner boundary than at the outer boundary, increasing linearly. This is because the outer boundary is closer to the liquid hydrogen pipe, resulting in more timely heat conduction. The temperature of the insulation layer near the liquid hydrogen and liquefied natural gas pipelines is stable at around 17 K and 90 K, respectively, indicating that the heat exchange between liquid hydrogen and liquefied natural gas is effectively blocked by the insulation layer, preventing liquid hydrogen from vaporizing and liquefied natural gas from solidifying. In addition, to ensure that liquid hydrogen and liquefied natural gas operate in a safe temperature range, intermediate refrigeration stations are usually set up for each of the two energy sources over long distances. Since liquefied natural gas is far from the superconducting layer, its heat source comes only from the inductive loss of the shielding layer. Therefore, the temperature rise of liquefied natural gas is small and it will not vaporize.

[0036] S400 employs a hybrid algorithm based on particle swarm optimization and artificial bee colony optimization to optimize the winding angle and winding direction of the superconducting tape, thereby improving the uniformity of current distribution and the system's current carrying capacity.

[0037] In the above embodiments, preferably, in step S400, the hybrid optimization algorithm includes: The HTSPAB1 algorithm uses the optimal solution of the particle swarm optimization algorithm as the initial solution for the artificial bee colony algorithm for global search. The HTSPAB2 algorithm achieves optimal solution information exchange through the co-evolution of two populations: a particle swarm optimization algorithm with dynamic inertia weights and an artificial bee colony algorithm.

[0038] In the above embodiments, preferably, the optimization design of the winding angle and winding direction of the superconducting tape includes: ① Optimize variables The current distribution in each layer of the superconducting tape is related to self-inductance and mutual inductance, which are determined by the radius of each superconducting tape layer. r The angle of spiral winding β and winding direction α The parameters of the superconducting layer are determined as follows: Figure 2 As shown. Since the inner radius of the superconducting tape is determined, and the spacing between each layer of superconducting tape is relatively fixed to the thickness of the superconducting tape, the optimization variable for the superconducting layer is the orthorium angle. β and winding direction α Assume there are 2 superconducting layers. n There are several optimization variables, using optimization vectors. K Represented as:

[0039]

[0040] In the formula, β The orientation angle of the superconducting tape; α The winding direction of the superconducting tape is 1 or -1; P The distance between two adjacent layers of superconducting tape; the radius of the superconducting tape. r ; ② Optimization Objective The goal of superconducting layer current sharing design is to minimize the current difference between layers; therefore, the fitness function is expressed as:

[0041] In the formula, I i (K) and I j (K) represents the optimization vector. K Time i Layer and first j Current in the superconducting tape; m and n These are the number of superconducting tape layers and the number of superconducting tape strands, respectively. f ( K The optimization vector corresponding to the minimum value. K This is the optimal structure for uniform current distribution in superconducting cables.

[0042] ③Constraints Considering the superconducting properties of superconducting tapes, the transport current of each superconducting layer in the optimization results should not exceed its critical current; otherwise, it will lead to quench failure. The current constraint condition of the superconducting layer optimization model is as follows:

[0043] In the formula, I i It is the first i The actual current in the layered superconducting tape; N i It is the first i The number of strips in a layered superconducting tape; I c It is the average critical current of the superconducting tape; k 1. k 2 and k 3 are the critical current degradation coefficients considering electromagnetic, strain, and thermal cycling effects on the cable; k 4 represents the safety margin in the design.

[0044] Based on the optimal structural parameters obtained from different optimization algorithms, the superconducting conductive layers were wound and arranged. Three-dimensional finite element models of the superconducting conductive layers optimized by different algorithms were established. Characteristic analysis was performed on these structures to observe the magnetic flux distribution and critical current density distribution characteristics of the optimized superconducting conductive layers, and the optimization effect of the superconducting conductive layers was further evaluated. The results show that the maximum magnetic flux of the superconducting layer optimized by HTSPSO is approximately 90 mT, with a relatively uniform magnetic flux distribution in the inner layer and larger magnetic flux at the edges of some parts in the outer layer. The maximum magnetic flux of the superconducting layer optimized by HTSPAB1 is reduced to approximately 50 mT, and the magnetic flux distribution of each superconductor layer is relatively more uniform than that of HTSPSO. The maximum magnetic flux density of the superconducting layer optimized by HTSPAB2 is reduced to approximately 20 mT, lower than that of HTSPSO and HTSPAB1. Therefore, the results indicate that, in terms of magnetic flux distribution, compared with the HTSPSO algorithm, HTSPAB2 and HTSPAB1 effectively reduce the magnetic induction intensity of the superconducting layer and improve the uniformity of the magnetic flux distribution, showing better optimization effects. Among them, HTSPAB2 shows the most outstanding optimization performance.

[0045] Taking an operating current of 1 kA as an example, the characteristic distribution is evaluated. The magnetic flux density and critical current density distribution of the superconducting conductive layer optimized by three algorithms are as follows: Figure 3As shown, (a) HTSPSO; (b) HTSPAB1; and (c) HTSPAB2. From the perspective of magnetic flux density distribution, the maximum values ​​of the superconducting conductive layer optimized by HTSPAB1 and HTSPAB2 are approximately 45 mT and 35 mT, respectively, which are about half lower than the 90 mT optimized by HTSPSO. This indicates that the proposed HTSPAB1 and HTSPAB2 optimization schemes effectively improve the magnetic distribution of the superconducting layer. From the perspective of critical current density distribution, the minimum critical current density of the superconducting conductive layer optimized by HTSPAB1 and HTSPAB2 is much greater than the value optimized by the HTSPSO algorithm. This indicates that the proposed hybrid optimization algorithm of HTSPAB1 and HTSPAB2 significantly improves the current-carrying capacity of the superconducting layer and reduces the critical current density decay.

[0046] Example 2: The above-described embodiment 1 provides a method for model building and characteristic analysis of a composite superconducting energy transmission system. Correspondingly, this embodiment provides a device for model building and characteristic analysis of a composite superconducting energy transmission system. The device provided in this embodiment can implement the method of embodiment 1. This device can be implemented through software, hardware, or a combination of both. For example, the device may include integrated or separate functional modules or units to perform the corresponding steps in the methods of embodiment 1. Since the device for model building and characteristic analysis in this embodiment is basically similar to the method embodiment, the description process in this embodiment is relatively simple. For relevant details, please refer to the description in embodiment 1. The device for model building and characteristic analysis in this embodiment is merely illustrative.

[0047] The device for model building and characteristic analysis of the composite superconducting energy transmission system provided in this embodiment includes: The first processing unit is used to establish the electromagnetic thermal coupling model of the composite superconducting energy transmission system. The second processing unit is used to set the physical field of the electromagnetic thermal coupling model of the composite superconducting energy transmission system. The third processing unit is used to analyze the operating characteristics of the composite superconducting energy transmission system using the finite element method and evaluate its electromagnetic and thermal coupling characteristics under the action of multi-physics field coupling. The fourth processing unit is used to optimize the winding angle and winding direction of the superconducting tape using a hybrid algorithm based on particle swarm optimization and artificial bee colony optimization, so as to improve the uniformity of current distribution and the current carrying capacity of the system.

[0048] Example 3: This embodiment provides a processing device for implementing the model establishment and characteristic analysis method of the composite superconducting energy transmission system provided in Embodiment 1. The processing device can be a client-side processing device, such as a mobile phone, laptop, tablet computer, desktop computer, etc., to execute the method of Embodiment 1.

[0049] The processing device includes a processor, a memory, a communication interface, and a bus. The processor, memory, and communication interface are connected via the bus to enable communication between them. The memory stores a computer program that can run on the processor. When the processor runs the computer program, it executes the method provided in Embodiment 1.

[0050] Preferably, the memory may be high-speed random access memory (RAM), and may also include non-volatile memory, such as at least one disk storage device.

[0051] Preferably, the processor can be any type of general-purpose processor such as a central processing unit (CPU) or a digital signal processor (DSP), and there is no limitation herein.

[0052] Example 4: The model establishment and characteristic analysis method of the composite superconducting energy transmission system in Embodiment 1 can be specifically implemented as a computer program product. The computer program product may include a computer-readable storage medium on which computer-readable program instructions for executing the method described in Embodiment 1 are loaded.

[0053] A computer-readable storage medium can be a tangible device that holds and stores instructions for use by an instruction execution device. A computer-readable storage medium can be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any combination thereof.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for model establishment and characteristic analysis of a composite superconducting energy transmission system, characterized in that, Includes the following steps: S100. Establish an electromagnetic-thermal coupling model for the composite superconducting energy transmission system; S200. Set up the physical field for the electromagnetic thermal coupling model of the composite superconducting energy transmission system; S300. Based on the electromagnetic thermal coupling model after the physical field settings, the finite element method is used to analyze the operating characteristics of the composite superconducting energy transmission system and evaluate its electromagnetic thermal coupling characteristics under the action of multi-physical field coupling. S400 employs a hybrid algorithm based on particle swarm optimization and artificial bee colony optimization to optimize the winding angle and winding direction of the superconducting tape, thereby improving the uniformity of current distribution and the system's current carrying capacity.

2. The model establishment and characteristic analysis method according to claim 1, characterized in that, The composite superconducting energy transmission system includes a first liquid hydrogen transmission pipeline, a first superconducting layer, a first electrical insulation layer, a second superconducting layer, a second liquid hydrogen transmission pipeline, a first thermal insulation layer, a liquefied natural gas transmission pipeline, a second electrical insulation layer, a superconducting shielding layer, and a second thermal insulation layer arranged coaxially from the inside out, wherein the first superconducting layer and the second superconducting layer are made of superconducting tape YBCO wound together.

3. The model establishment and characteristic analysis method according to claim 2, characterized in that, Step S100 specifically includes the following steps: S101. Construct a two-dimensional axisymmetric geometric model of the composite superconducting energy transmission system; S102. Mesh the two-dimensional axisymmetric geometric model, where the pipe part is meshed using a mapped mesh and the air domain is meshed using a free triangular mesh. S103. Define the boundary conditions for the two-dimensional axisymmetric geometric model. Let the central axis of the pipe be the inner side, the radial direction outward be the outer side, the side closer to the two superconducting layers be the inner boundary, the side farther from the superconducting layers be the outer boundary, and the inlet and outlet of the pipe be the upper and lower boundaries.

4. The model establishment and characteristic analysis method according to claim 3, characterized in that, Step S200 specifically includes the following steps: S201. Define the basic properties of the electromagnetic thermal coupling model, including the width, thickness, critical current density under zero field, and rated current of the superconducting tape; S202. Set the material properties of the superconducting tape, including relative permittivity, relative permeability, density, thermal conductivity, heat capacity, and resistivity; S203. Set the magnetic field boundary conditions, set the outer boundary of the air domain to 0, and apply current excitation to the superconducting layer by point-by-point constraint method; S204. Establish a solid heat transfer interface and set the power loss of the superconducting layer as the heat source; S205. Establish a multiphysics interface and add an electromagnetic thermal coupling interface and a temperature coupling interface.

5. The model building and characteristic analysis method according to claim 4, characterized in that, The electromagnetic thermal coupling characteristics include: ① Magnetic flux density distribution: The electrical insulation layer has the highest magnetic flux density, with an average magnetic flux of about 0.05 T, and the distribution is uniform. The magnetic flux density distribution shows that the inner boundary is larger and gradually decreases at the outer boundary. The magnetic field outside the shielding layer is close to 0. The magnetic flux density is basically uniform in the middle of the pipe, with a certain edge effect at the boundary. The magnetic flux density of other layers gradually decreases radially outward. ② Critical current density distribution: The critical current density is basically uniform and symmetrical in the inner and outer superconducting layers. The attenuation is greatest at the upper and lower boundaries of the superconducting layer, followed by the inner boundary, and the attenuation is smallest at the outer boundary. ③ Temperature distribution: The temperature of the insulation layer is stable at around 17 K and 90 K on the side near the liquid hydrogen and liquefied natural gas pipelines, respectively, and the insulation layer can effectively block heat exchange.

6. The model building and characteristic analysis method according to claim 5, characterized in that, In step S400, the hybrid optimization algorithm includes: The HTSPAB1 algorithm uses the optimal solution of the particle swarm optimization algorithm as the initial solution for the artificial bee colony algorithm for global search. The HTSPAB2 algorithm achieves optimal solution information exchange through the co-evolution of two populations: a particle swarm optimization algorithm with dynamic inertia weights and an artificial bee colony algorithm.

7. The model establishment and characteristic analysis method according to claim 6, characterized in that, In step S400, the optimization design of the winding angle and winding direction of the superconducting tape includes: ① Optimize variables The optimization variable for the superconducting layer is the orthorium angle. β and winding direction α Assume there are 2 superconducting layers. n There are several optimization variables, using optimization vectors. K Represented as: In the formula, β The orientation angle of the superconducting tape; α The winding direction of the superconducting tape is 1 or -1; P The distance between two adjacent layers of superconducting tape; the radius of the superconducting tape. r ; ② Optimization Objective The goal of superconducting layer current sharing design is to minimize the current difference between layers; therefore, the fitness function is expressed as: In the formula, I i (K) and I j (K) represents the optimization vector. K Time i Layer and first j Current in the superconducting tape; m and n These are the number of superconducting tape layers and the number of superconducting tape strands, respectively. ③Constraints The current constraint condition for the superconducting layer optimization model is: In the formula, I i It is the first i The actual current in the layered superconducting tape; N i It is the first i The number of strips in a layered superconducting tape; I c It is the average critical current of the superconducting tape; k 1. k 2 and k 3 are the critical current degradation coefficients considering electromagnetic, strain, and thermal cycling effects on the cable; k 4 represents the safety margin in the design.

8. A device for model establishment and characteristic analysis of a composite superconducting energy transmission system, characterized in that, include: The first processing unit is used to establish the electromagnetic thermal coupling model of the composite superconducting energy transmission system. The second processing unit is used to set the physical field of the electromagnetic thermal coupling model of the composite superconducting energy transmission system. The third processing unit is used to analyze the operating characteristics of the composite superconducting energy transmission system using the finite element method based on the electromagnetic thermal coupling model after the physical field is set, and to evaluate its electromagnetic thermal coupling characteristics under the action of multi-physical field coupling. The fourth processing unit is used to optimize the winding angle and winding direction of the superconducting tape using a hybrid algorithm based on particle swarm optimization and artificial bee colony optimization, so as to improve the uniformity of current distribution and the current carrying capacity of the system.

9. A computer-readable storage medium, characterized in that, The device contains a computer program that is executed by a processor to control the device where the processor is located to implement the steps of the model building and characteristic analysis apparatus for the composite superconducting energy transmission system according to any one of claims 1 to 7.

10. A computer device, characterized in that, It includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the device for model building and characteristic analysis of the composite superconducting energy transmission system according to any one of claims 1 to 7.

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