Electromagnetic-thermal flow coupling simulation method, device, medium and program product for superconducting power equipment based on iterative algorithm

Abstract

The application relates to a superconducting power equipment electromagnetic-thermal flow coupling simulation method, equipment, medium and program product based on an iterative algorithm, the simulation method comprises the following steps: constructing a simplified basic model of superconducting power equipment; calculating coil steady-state alternating current loss distribution; simulating and calculating superconducting coil and cooling liquid temperature distribution; feeding back the obtained superconducting coil and cooling liquid temperature distribution to an electromagnetic simulation process as an input temperature boundary condition to calculate alternating current loss, and then feeding back the alternating current loss to a thermal flow simulation process to calculate temperature distribution, forming an iterative cycle; determining superconducting equipment total alternating current loss according to alternating current loss distribution in the iteration, and calculating a variation rate based on the total alternating current loss before and after. Compared with the prior art, the application can comprehensively consider the mutual influence of electromagnetic fields and thermal fields under the premise that the simulation complexity is not significantly increased, and can more accurately obtain superconducting power equipment alternating current loss and temperature.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of superconducting power equipment, and in particular to a superconducting power equipment electromagnetic-thermal flow coupling simulation method, device, medium and program product based on an iterative algorithm. BACKGROUND

[0002] With the continuous development of the power system, there is an increasing demand for large-capacity and high-energy-efficiency power equipment. Superconducting power equipment emerges as the times require, which is developed based on the superconducting characteristics of superconducting materials in a specific low-temperature environment. Superconducting materials exhibit extremely low loss when current passes through, have the advantages of high energy efficiency, high current carrying capacity and compact design, which makes the application of superconducting power equipment in the power system have great potential, covering superconducting reactors, superconducting cables, superconducting transformers, superconducting current limiters, superconducting fans and other types, which can effectively improve the overall efficiency of the power system and optimize the system structure.

[0003] However, the operating characteristics of superconducting power equipment are extremely complex. The loss and current-carrying capacity of superconducting materials are strongly related to temperature, magnetic field and electric field, and they are extremely sensitive to small changes in electromagnetic and temperature. When simulating and analyzing the loss and temperature of superconducting power equipment, the mutual influence between electromagnetic field and thermal field must be fully considered to ensure that the simulation results can accurately reflect the actual operating state of the equipment.

[0004] However, due to the significant nonlinearity of superconducting tapes and the large width-thickness ratio, combined with the fluid simulation of the cooling liquid involved in the thermal simulation process, when simulating the electromagnetic field and thermal field of superconducting power equipment separately, the simulation complexity is already high. If the electromagnetic field and thermal field are simulated jointly, the complexity will be greatly increased, which not only puts high requirements on computing resources, but also makes the simulation process difficult to be completed efficiently and accurately.

[0005] In summary, the existing superconducting power equipment simulation technology has many difficulties and challenges in the face of electromagnetic-thermal flow coupling simulation, and there is an urgent need for a simulation method that can consider the mutual influence of electromagnetic field and thermal field without significantly increasing the simulation complexity, and can accurately obtain the AC loss and temperature of superconducting power equipment, to meet the needs of superconducting power equipment research and development, design, operation optimization and other aspects, and promote the further development and application of superconducting power equipment in the power field. SUMMARY

[0006] The purpose of the present application is to overcome the defects of the prior art, and provide an electromagnetic-thermal flow coupling simulation method, device, medium and program product of superconducting power equipment based on an iterative algorithm, wherein electromagnetic simulation and thermal simulation are relatively independent, and the results of electromagnetic simulation and thermal simulation are taken as inputs of each other, the mutual influence of electromagnetic field and thermal field can be comprehensively considered without significantly increasing the simulation complexity, and the alternating loss and temperature of superconducting power equipment can be more accurately obtained.

[0007] The purpose of the present application can be achieved by the following technical solutions.

[0008] The present application provides a superconducting power equipment electromagnetic-thermal flow coupling simulation method based on an iterative algorithm in the first aspect, comprising the following steps.

[0009] S1: constructing a simplified basic model of superconducting power equipment;

[0010] S2: setting an initial temperature, and calculating the coil steady-state alternating loss distribution according to the simplified basic model in S1;

[0011] S3: simulating and calculating the superconducting coil and cooling liquid temperature distribution according to the simplified basic model in S1 and the superconducting coil alternating loss distribution data obtained in S2;

[0012] S4: feeding back the superconducting coil and cooling liquid temperature distribution obtained in S3 to the electromagnetic simulation process in S2 as an input temperature boundary condition to calculate the alternating loss, and feeding back the alternating loss to the thermal flow simulation process in S3 to calculate the temperature distribution, forming an iterative cycle;

[0013] S5: determining the total alternating loss of the superconducting equipment according to the alternating loss distribution in the iteration in S4, and calculating the change rate based on the total alternating loss before and after.

[0014] Further, in S1, the following steps are specifically included:

[0015] Considering the structural characteristics of superconducting power equipment and the accuracy requirement of electromagnetic-thermal flow coupling simulation, a simulation basic model of superconducting power equipment is constructed, the non-critical and simulation complexity affecting components are removed by simplifying the original model of superconducting power equipment, the core components carrying current are extracted and the coil and cooling liquid inlet and outlet geometry are simplified, and the cooling liquid area is selected.

[0016] Further, in S2, the following steps are specifically included:

[0017] Based on the basic model constructed in S2, the superconducting coil part in the basic model is extracted, the initial temperature of the superconducting coil is set according to the superconducting material characteristics and the equipment operating condition, the transient electric field and current distribution of the superconducting coil are simulated and calculated, and the coil steady-state alternating loss distribution is derived based on the calculation results.

[0018] Further, in S3, the steps specifically include the following:

[0019] According to the basic model determined in S1 and the AC loss data of the superconducting coil obtained in S2, the heat leakage of the dewar and the sleeve in the superconducting power equipment is applied to the wall surface in the form of heat flow boundary, the AC loss of the superconducting coil is accurately loaded on the superconducting coil as a thermal excitation, a material similar to the thermal properties of the superconducting tape is used to replace the superconducting tape to simplify the thermal property model, the boundary types of the cooling liquid inlet and outlet are set according to the principles of fluid mechanics and heat transfer and combined with the actual operation environment of the equipment, and the steady-state simulation calculation is carried out while fully considering the influence of gravity, so as to obtain the temperature distribution of the superconducting coil and the cooling liquid.

[0020] Further, in S4, the steps specifically include the following:

[0021] The temperature distribution data of the superconducting coil obtained in S3 is input as feedback information into the electromagnetic characteristic simulation process of the superconducting coil in the basic model in S1 as the temperature condition for the simulation calculation of the transient electric field and current distribution of the superconducting coil again, and the steps of the AC loss distribution calculation of the superconducting coil and the temperature distribution calculation of the superconducting coil and the cooling liquid are repeated, thereby forming an iterative loop mechanism of electromagnetic-heat flow coupling simulation;

[0022] In the iteration process, the electromagnetic simulation parameters are adaptively adjusted according to the temperature distribution results obtained in the previous cycle, and the heat flow distribution is recalculated based on the adjusted electromagnetic simulation results, and the process is repeated in turn until the convergence condition is met.

[0023] Further, in S5, the steps specifically include the following:

[0024] According to the AC loss distribution data of the superconducting coil obtained in each cycle in the iteration process of S4, a calculation method suitable for the structural characteristics and operation mode of the superconducting power equipment is used to determine the total AC loss of the superconducting power equipment.

[0025] Meanwhile, based on the total AC loss data determined by the previous and subsequent two iterations, the change rate is determined according to the predetermined calculation rules based on the electromagnetic-heat flow coupling relationship and engineering application requirements, and when the change rate is less than a preset threshold, it is determined that the iteration converges, and then the total AC loss value of the superconducting power equipment and the corresponding temperature distribution data of the superconducting coil and the cooling liquid at this time are output.

[0026] Further, in S5, the convergence threshold in the iteration calculation process is set based on the type of the superconducting power equipment, the operation condition, and the required simulation accuracy.

[0027] The second aspect of the present application provides an electronic device comprising a memory and a processor, wherein the processor is configured to execute a program in the memory to implement the electromagnetic-thermal coupling simulation method for superconducting power equipment based on the iterative algorithm as described above.

[0028] The third aspect of the present application provides a storage medium comprising computer executable instructions, wherein the computer executable instructions, when executed by a computer processor, are configured to implement the electromagnetic-thermal coupling simulation method for superconducting power equipment based on the iterative algorithm as described above.

[0029] The fourth aspect of the present application provides a computer program product comprising a computer program, wherein the computer program, when executed by a processor, implements the electromagnetic-thermal coupling simulation method for superconducting power equipment based on the iterative algorithm as described above.

[0030] Compared with the prior art, the present application has the following beneficial effects:

[0031] 1) The present application successfully solves the problem of high complexity of electromagnetic field and thermal field joint simulation of superconducting power equipment by relatively independently and iteratively inputting electromagnetic simulation and thermal simulation without significantly increasing the simulation complexity. This iterative algorithm can accurately consider the mutual influence of electromagnetic field and thermal field, so that the simulation result is more in line with the actual operating conditions of the superconducting power equipment, providing a more reliable basis for the optimization design of the equipment, and helping to improve the performance and stability of the superconducting power equipment, and reducing the trial and error cost and time cost in the research and development process.

[0032] 2) The simulation method proposed in the present application can accurately obtain the AC loss and temperature of the superconducting power equipment. Accurate AC loss calculation can help improve the energy utilization efficiency of superconducting power equipment, avoid energy waste or equipment overload caused by inaccurate loss estimation; and accurate temperature acquisition is crucial for the stable operation of superconducting materials, which can ensure that the superconducting power equipment works within a safe temperature range, prolong the service life of superconducting materials, improve the reliability and safety of equipment operation, further promote the large-scale application and popularization of superconducting power equipment in power systems, and promote the development of the power industry in a more efficient and intelligent direction. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 A schematic diagram of a simplified model of a superconducting reactor;

[0034] Figure 2 A schematic diagram of a superconducting coil model (single phase) of a superconducting reactor;

[0035] Figure 3 A spatial AC loss distribution diagram (unit: W) of a three-phase superconducting reactor;

[0036] Figure 4 Temperature distribution map (unit: K) of the three-phase superconducting reactor;

[0037] Figure 5 Total loss change map in the iteration process of the three-phase superconducting reactor;

[0038] Figure 6 Total flow chart of example 1. DETAILED DESCRIPTION

[0039] The present application will be described in detail below in conjunction with the drawings and specific examples. In the technical solution, if the component model, material name, connection structure, control method, algorithm and other features are not explicitly stated, they are considered as common technical features disclosed in the prior art.

[0040] Example 1

[0041] The first aspect of the present application provides a superconducting power equipment electromagnetic-thermal flow coupling simulation method based on an iterative algorithm, comprising the following steps:

[0042] S1: constructing a simplified basic model of the superconducting power equipment;

[0043] In S1, the following steps are specifically included:

[0044] Considering the structural characteristics of the superconducting power equipment and the accuracy requirement of the electromagnetic-thermal flow coupling simulation, a simulation basic model of the superconducting power equipment is constructed. By simplifying the original model of the superconducting power equipment, the non-critical components affecting the simulation complexity are removed, the core components carrying current are extracted, and the coil and cooling liquid inlet and outlet geometric structures are simplified, and the cooling liquid area is selected.

[0045] In step S1, the present application follows the principle of "simplification to focus on the core, precision to meet the needs" to construct the simplified basic model of superconducting power equipment. First, the structural characteristics of superconducting power equipment are fully considered, because the structure of the equipment determines the basic mode of its electromagnetic and heat flow behavior; at the same time, according to the accuracy requirement of electromagnetic-thermal coupling simulation, to ensure that the simplified model can effectively reduce the simulation complexity on the premise of meeting the engineering accuracy requirement. On this basis, the original model of superconducting power equipment is simplified, and the non-key parts that increase the simulation complexity are removed, which have little effect on the coupling relationship between electromagnetic field and thermal field, and removing them can reduce unnecessary calculation and data processing difficulty. Then, the core components carrying current are extracted, because current is the key factor of electromagnetic field and heat loss, and the electromagnetic and thermal behavior of core components plays a decisive role in the performance of the whole equipment. Further simplify the coil and cooling liquid inlet and outlet geometry of the core component, in order to reduce the geometric complexity of the model while retaining the key features, facilitate subsequent simulation calculation and analysis. At the same time, the cooling liquid area is selected, which plays a crucial role in heat exchange in superconducting power equipment, and selecting the cooling liquid area helps to accurately simulate the heat transfer process and provide clear boundary and scope for subsequent thermal simulation calculation.

[0046] S2: Set initial temperature, calculate coil steady-state ac loss distribution according to the simplified basic model in S1;

[0047] In S2, the following steps are included:

[0048] Based on the basic model constructed in S2, the superconducting coil part in the basic model is extracted, the initial temperature of the superconducting coil is set according to the characteristics of superconducting material and the operation condition of the equipment, the transient electric field and current distribution of the superconducting coil are simulated, and the steady-state ac loss distribution of the coil is derived based on the calculation results.

[0049] In step S2, the application follows the principle of "deriving steady-state loss based on initial conditions through transient simulation" to calculate the coil steady-state AC loss distribution. First, based on the simplified basic model constructed in S1, the superconducting coil part is extracted, because the superconducting coil is the key area to generate AC loss. Then, according to the characteristics of superconducting materials (such as the characteristics of critical current density, resistivity, etc. changing with temperature) and the actual operating conditions of the device (such as current size, frequency, etc.), the initial temperature of the superconducting coil is reasonably set. The setting of the initial temperature provides the necessary starting conditions for the subsequent electromagnetic simulation calculation. Next, the transient electric field and current distribution simulation of the superconducting coil is carried out. Transient simulation can capture the dynamic change process of electric field and current in time dimension, so as to more accurately reflect the state of electromagnetic field at different time points. Based on the results of transient simulation calculation, the coil steady-state AC loss distribution is derived, because the steady-state loss is the key parameter of the device in long-time stable operation. By analyzing the steady-state loss distribution from the transient process, accurate electromagnetic loss data can be provided for subsequent thermal simulation and performance evaluation of the device, and then the precise simulation analysis of the electromagnetic-thermal coupling characteristics of superconducting power equipment is realized.

[0050] S3: According to the simplified basic model in S1 and the superconducting coil AC loss distribution data obtained in S2, the temperature distribution of the superconducting coil and the cooling liquid is simulated.

[0051] In S3, the following steps are included:

[0052] According to the basic model determined in S1 and the superconducting coil AC loss data obtained in S2, the heat leakage of the dewar and the sleeve in the superconducting power equipment is applied to the wall surface in the form of heat flow boundary, the AC loss of the superconducting coil is accurately loaded on the superconducting coil as a thermal excitation, a material similar to the thermal properties of superconducting tape is used to replace the superconducting tape to simplify the thermal property model, the boundary type of the cooling liquid inlet and outlet is set according to the principles of fluid mechanics and heat transfer and combined with the actual operating environment of the device, and the steady-state simulation calculation is carried out while fully considering the influence of gravity, so as to obtain the temperature distribution of the superconducting coil and the cooling liquid.

[0053] In step S3, the present application uses the principle of "multi-factor comprehensive simulation" to simulate and calculate the temperature distribution of the superconducting coil and the cooling liquid according to the basic model determined in S1 and the AC loss data of the superconducting coil obtained in S2. First, the heat leakage of the dewar and the sleeve is applied to the wall surface in the form of a heat flow boundary to simulate the heat exchange between the equipment and the outside world in actual operation. Then, the AC loss of the superconducting coil is accurately loaded on the superconducting coil as a heat excitation, because the AC loss is the main heat source causing the temperature rise of the coil. In order to simplify the thermal property model, a material similar to the thermal properties of the superconducting tape is used to replace the superconducting tape, which can not only ensure the accuracy of the simulation, but also reduce the complexity of the model. According to the principles of fluid mechanics and heat transfer, and combined with the actual operation environment of the equipment, the boundary types of the cooling liquid inlet and outlet, such as velocity, temperature, pressure and other boundary conditions, are set to truly reflect the flow and heat transfer process of the cooling liquid. At the same time, the influence of gravity on the flow and temperature distribution of the cooling liquid is fully considered to carry out steady-state simulation calculation. Through comprehensive consideration of multiple factors such as heat leakage, AC loss, material thermal properties, cooling liquid flow and gravity, the temperature distribution of the superconducting coil and the cooling liquid is finally obtained.

[0054] S4: The temperature distribution of the superconducting coil and the cooling liquid obtained in S3 is fed back to the electromagnetic simulation process in S2 as an input temperature boundary condition to calculate the AC loss, and then the AC loss is fed back to the heat flow simulation process in S3 to calculate the temperature distribution, forming an iterative cycle.

[0055] S4 specifically includes the following steps:

[0056] The temperature distribution data of the superconducting coil obtained in S3 is input as feedback information into the electromagnetic characteristic simulation process of the superconducting coil in the basic model in S1 as the temperature condition for the simulation calculation of the transient electric field and current distribution of the superconducting coil again, and the steps of AC loss distribution calculation of the superconducting coil and temperature distribution calculation of the superconducting coil and the cooling liquid are repeated, thereby forming an iterative cycle mechanism of electromagnetic-heat flow coupling simulation;

[0057] In the iterative process, the electromagnetic simulation parameters are adaptively adjusted according to the temperature distribution results obtained in the previous cycle, and the heat flow distribution is recalculated based on the adjusted electromagnetic simulation results, and the process is repeated in turn until the convergence condition is met.

[0058] In step S4, the present application adopts the principle of "two-way feedback iteration optimization" to realize the accurate calculation of electromagnetic-thermal flow coupling simulation. Specifically, the temperature distribution of the superconducting coil and the cooling liquid obtained in S3 is fed back to the electromagnetic simulation process in S2 as a new input temperature boundary condition to recalculate the alternating current loss, because the change of temperature will affect the electromagnetic properties of superconducting materials, and then change the distribution of alternating current loss. Subsequently, the recalculated alternating current loss is fed back to the thermal flow simulation process in S3 for updating the calculation of temperature distribution, because the heat generated by alternating current loss will change the temperature field of superconducting coil and cooling liquid. Through this two-way feedback mechanism of feeding back the electromagnetic simulation results to the thermal flow simulation and then feeding back the thermal flow simulation results to the electromagnetic simulation, an iterative cycle is formed. In each iteration process, the electromagnetic simulation parameters are adjusted according to the temperature distribution results obtained in the previous iteration to more accurately reflect the changes of electromagnetic properties under actual working conditions; at the same time, the thermal flow distribution is recalculated based on the adjusted electromagnetic simulation results to further accurately simulate the temperature field. This iterative cycle will be repeated in turn until the calculation results meet the preset convergence condition, i.e. the total alternating current loss change rate calculated by the previous and the next iteration is less than the set threshold, so as to ensure that the final superconducting coil alternating current loss distribution and temperature distribution data accurately reflect the electromagnetic-thermal flow coupling characteristics of superconducting power equipment in actual operation

[0059] S5: determining the total alternating current loss of the superconducting device according to the alternating current loss distribution in the iteration in S4, and calculating the change rate of the total alternating current loss before and after.

[0060] In S5, the following steps are specifically included:

[0061] According to the alternating current loss distribution data of the superconducting coil obtained in each cycle of the iteration process in S4, the total alternating current loss of the superconducting power device is determined by using a calculation method suitable for the structural characteristics and operation mode of the superconducting power device;

[0062] At the same time, based on the total alternating current loss data determined by the previous and the next iteration calculation, the change rate is determined according to the predetermined calculation rule based on the electromagnetic-thermal flow coupling relationship and engineering application requirements. When the change rate is less than the preset threshold, it is determined that the iteration converges, and then the total alternating current loss value of the superconducting power device and the corresponding temperature distribution data of the superconducting coil and the cooling liquid are output.

[0063] The convergence threshold in the iteration calculation process is set based on the type of superconducting power device, operating condition and required simulation accuracy.

[0064] In step S5, the present application determines the total AC loss of the superconducting power device and the corresponding temperature distribution data following the principle of "iterative result evaluation and convergence determination". First, the AC loss distribution data of the superconducting coil obtained in each loop of the S4 iteration process is collected, which covers the loss under different temperature conditions. Then, the distribution data is integrated and analyzed by using a calculation method suitable for the structural characteristics (such as coil layout, cooling system configuration, etc.) and operation mode (such as current size, operation frequency, etc.) of the superconducting power device, so as to accurately determine the total AC loss of the entire superconducting power device. At the same time, based on the total AC loss data determined by the previous and subsequent two iterations, the change rate of the total AC loss is calculated according to the predetermined calculation rule, which comprehensively considers the electromagnetic-thermal flow coupling relationship and the demand for precision and efficiency in engineering application. When the change rate is less than the pre-set threshold value, it indicates that the iteration calculation has tended to be stable, and the error is within an acceptable range, at which time it is determined that the iteration converges. Finally, the total AC loss value of the superconducting power device determined at this time and the temperature distribution data of the superconducting coil and the cooling liquid corresponding thereto are output, which provides key quantitative basis for the design optimization, performance evaluation and operation control of the superconducting power device, and ensures the accuracy and reliability of the simulation results.

[0065] Embodiment 2

[0066] The embodiment provides an electronic device including a memory and a processor, wherein the processor is configured to execute a program in the memory to implement the above-mentioned superconducting power device electromagnetic-thermal flow coupling simulation method based on an iterative algorithm. The electronic device stores the program code, model data, parameter settings and intermediate calculation results and other key information required for simulation in the built-in memory, providing data support for the simulation process. The powerful processor is responsible for efficiently executing the program in the memory, accurately performing complex electromagnetic field and thermal field calculations, including but not limited to transient electric field and current distribution calculation, steady-state AC loss derivation, temperature distribution simulation and parameter adjustment in the iteration loop and other key steps. The configuration of such an electronic device enables the simulation method to quickly and accurately complete the overall simulation analysis of the electromagnetic-thermal flow coupling characteristics of the superconducting power device with the high-speed processing capability of modern computing technology, thereby providing real-time and efficient technical support for the research and development, performance optimization and fault prediction of superconducting power devices, and promoting the rapid development and wide application of superconducting power technology in practical engineering applications.

[0067] Embodiment 3

[0068] The embodiment provides a storage medium containing computer executable instructions, which, when executed by a computer processor, are used to execute the superconducting power equipment electromagnetic-thermal flow coupling simulation method based on an iterative algorithm. The storage medium can be an optical disc, a hard disk, a U disk, a solid state memory and the like, which stores computer program codes specially written for realizing the simulation method. When the storage medium containing the computer executable instructions is loaded into a computer device, and the instructions in the storage medium are executed by a computer processor, the superconducting power equipment simplified model construction, initial temperature setting and alternating loss calculation, temperature distribution simulation calculation and iteration cycle and the like can be sequentially completed according to preset steps and logic. This makes the simulation method break through the limitation of hardware devices, and flexibly run on different computer platforms in the form of software, greatly improving the portability and universality of the simulation method.

[0069] Embodiment 4

[0070] The embodiment provides a computer program product, which comprises a computer program, and the computer program realizes the superconducting power equipment electromagnetic-thermal flow coupling simulation method based on an iterative algorithm when executed by a processor. The computer program product encapsulates complete simulation program codes, and the codes can realize a series of complex simulation steps from superconducting power equipment model simplification, initial condition setting to electromagnetic field and thermal field iterative coupling calculation. When the computer program is executed by the processor, the computer program can automatically call related calculation modules and algorithms, efficiently process a large amount of simulation data, and generate electromagnetic-thermal flow coupling characteristic results of the superconducting power equipment under different operating conditions. The form of the computer program product not only facilitates installation and deployment in different computer systems and network environments, but also can continuously optimize the simulation algorithm and add new functional modules through software updating, so as to adapt to the needs of the continuous development of superconducting power equipment technology and the increasingly diversified application scenarios.

[0071] Application Example 1

[0072] The total flow chart of the application example is as shown in Figure 6 .

[0073] 1. Simplify the superconducting power equipment model, remove the relatively complex insulation framework, sleeve, extract the main components carrying current, simplify the geometric structure of the coil, the cooling liquid inlet and the like, and select the cooling liquid area. Taking a 10kV / 1Mvar compact superconducting shunt reactor as an example, the framework and connecting piece of the superconducting reactor are removed, the superconducting coil is simplified into a corresponding geometric shape, the liquid nitrogen area is selected and the liquid nitrogen inlet and outlet structure is simplified to construct a basic model, as shown in Figure 1 .

[0074] 2. Extract the superconducting coil part, as shown in Figure 2 The initial temperature of the superconducting coil is set, the transient electric field and current distribution of the superconducting coil is simulated, and the steady-state AC loss distribution P of the coil is calculated. The spatial AC loss distribution map of the three-phase superconducting reactor is shown in Figure 3 Due to the existence of zero initial condition, the calculation result is not stable in the first half cycle. The AC loss power of the second half cycle is averaged to calculate the AC loss distribution of the superconducting coil, as shown in equation (1).

[0075]

[0076] For example, the initial temperature of the superconducting coil is set to 77K, and the set AC current I = I peak sin(2πft) is input.

[0077] 3. The heat leakage of the dewar and the sleeve is added as a heat flow boundary to the wall, and the AC loss of the superconducting coil is loaded as a thermal excitation on the superconducting coil. Since the base Hastelloy accounts for most of the thickness of the high-temperature superconducting tape, the thermal properties are similar to those of stainless steel, and stainless steel is used instead of superconducting tape. According to the principles of fluid mechanics and heat transfer, the boundary type related to the speed and temperature of the cooling liquid inlet is set, and the corresponding boundary type is set at the outlet. The simulation takes into account the effect of gravity and only focuses on the steady-state situation. The temperature distribution of the superconducting coil and the liquid nitrogen of the superconducting power device is obtained by simulation. The temperature distribution map of the three-phase superconducting reactor is shown in Figure 3 , the liquid nitrogen enters the setting speed inlet 0.8m / s, 70K, and the liquid nitrogen outlet is set as outflow boundary.

[0078] 4. The temperature distribution of the superconducting coil obtained by calculation is taken as the temperature condition of step 2, and steps 2 and 3 are repeated to iteratively calculate the temperature and AC loss distribution of the superconducting coil.

[0079] 5. The AC loss distribution P v of the superconducting coil is calculated to obtain the total AC loss P of the superconducting power device, as shown in equation (2). For the total AC loss P n and P n-1 of the two iteration results, the change rate δ is defined, as shown in equation (3). Figure 4 The total loss change in the iteration process of the three-phase superconducting reactor is δ. If the change rate is less than 1%, the result is considered to be convergent, and the total AC loss P and temperature of the superconducting power device are output.

[0080] P = ∫ V P v dV (2)

[0081]

[0082] The foregoing description of the embodiments has been presented for the purpose of illustration and description. It is not intended to be exhaustive or to limit the application to the precise form disclosed. Modifications and variations are possible in light of the above teachings or can be acquired from practice of the application. As well, the description is presented in the context of the preferred embodiments as a number of alternatives. It is not intended to limit the application to the precise form described.

Claims

1. A simulation method for electromagnetic-thermal-fluid coupling of superconducting power devices based on an iterative algorithm, characterized in that, Includes the following steps: S1: Construct a simplified basic model of the superconducting power device; S2: Set the initial temperature and calculate the steady-state AC loss distribution of the coil based on the simplified basic model in S1; S3: Based on the simplified basic model in S1 and the AC loss distribution data of the superconducting coil obtained in S2, simulate and calculate the temperature distribution of the superconducting coil and the coolant. S4: Feed back the temperature distribution of the superconducting coil and coolant obtained in S3 to the electromagnetic simulation process in S2 as input temperature boundary conditions to calculate AC loss, and then feed back the AC loss to the heat flow simulation process in S3 to calculate temperature distribution, forming an iterative loop; S5: Determine the total AC loss of the superconducting device based on the AC loss distribution in the iteration of S4, and calculate the rate of change based on the total AC loss before and after; S3 specifically includes the following steps: Based on the basic model determined by S1 and the AC loss data of the superconducting coil obtained by S2, the heat leakage of the Dewar and the bushing in the superconducting power equipment is applied to the wall in the form of heat flow boundary. The AC loss of the superconducting coil is accurately applied to the superconducting coil as a thermal excitation. A material with similar thermal properties to the superconducting tape is used to replace the superconducting tape to simplify the thermal property model. Based on the principles of fluid mechanics and heat transfer and combined with the actual operating environment of the equipment, the boundary types of the coolant inlet and outlet are set. At the same time, the influence of gravity is fully considered to carry out steady-state simulation calculations, thereby obtaining the temperature distribution of the superconducting coil and the coolant. S4 specifically includes the following steps: The temperature distribution data of the superconducting coil obtained in S3 is used as feedback information and input into the electromagnetic characteristic simulation process with the superconducting coil in the S1 basic model as the object. This serves as the temperature condition for performing the transient electric field and current distribution simulation calculation of the superconducting coil again. The steps of calculating the AC loss distribution of the superconducting coil and the temperature distribution of the superconducting coil and coolant are repeated, thus forming an iterative loop mechanism for electromagnetic-thermal-fluid coupling simulation. During the iteration process, the electromagnetic simulation parameters are adaptively adjusted based on the temperature distribution results obtained in the previous cycle, and the heat flow distribution is recalculated based on the adjusted electromagnetic simulation results. This process is repeated until the convergence condition is met.

2. The electromagnetic-thermal-fluid coupling simulation method for superconducting power devices based on an iterative algorithm according to claim 1, characterized in that, S1 specifically includes the following steps: Considering the structural characteristics of superconducting power equipment and the accuracy requirements of electromagnetic-thermal-fluid coupling simulation, a basic simulation model of superconducting power equipment is constructed. By simplifying the original model of superconducting power equipment, non-critical components that affect the simulation complexity are removed, the core components that carry current are extracted and their coil and coolant inlet / outlet geometry is simplified, and the coolant region is selected.

3. The electromagnetic-thermal-fluid coupling simulation method for superconducting power devices based on an iterative algorithm according to claim 1, characterized in that, S2 specifically includes the following steps: Based on the basic model constructed by S2, the superconducting coil part in the basic model is extracted. According to the characteristics of superconducting materials and the operating conditions of the equipment, the initial temperature of the superconducting coil is set, and the transient electric field and current distribution of the superconducting coil are simulated and calculated. Based on the calculation results, the steady-state AC loss distribution of the coil is derived.

4. The electromagnetic-thermal-fluid coupling simulation method for superconducting power devices based on an iterative algorithm according to claim 1, characterized in that, S5 specifically includes the following steps: Based on the AC loss distribution data of the superconducting coil obtained in each iteration of the S4 process, the total AC loss of the superconducting power equipment is determined by adopting a calculation method that is compatible with the structural characteristics and operating mode of the superconducting power equipment. Simultaneously, based on the total AC loss data determined by the two iterations, its rate of change is determined according to the predetermined calculation rules based on the electromagnetic-thermal-fluid coupling relationship and engineering application requirements. When the rate of change is less than the preset threshold, the iteration is determined to be converged, and then the total AC loss value of the superconducting power device and the corresponding temperature distribution data of the superconducting coil and coolant are output.

5. The electromagnetic-thermal-fluid coupling simulation method for superconducting power devices based on an iterative algorithm according to claim 1, characterized in that, In S5, the convergence threshold during the iterative calculation process is set based on the type of superconducting power equipment, operating conditions, and required simulation accuracy.

6. An electronic device, comprising a memory and a processor, characterized in that, The processor is used to execute the program in the memory to implement the electromagnetic-thermal-fluid coupling simulation method for superconducting power devices based on an iterative algorithm as described in any one of claims 1 to 5.

7. A storage medium containing computer-executable instructions, characterized in that, When executed by a computer processor, the storage medium of the computer-executable instructions is used to perform the electromagnetic-thermal-fluid coupling simulation method for superconducting power devices based on an iterative algorithm as described in any one of claims 1 to 5.

8. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the electromagnetic-thermal-fluid coupling simulation method for superconducting power devices based on an iterative algorithm as described in any one of claims 1 to 5.

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