A method and terminal for analyzing arc characteristics of fuse based on thermoelectric coupling

Abstract

The present invention provides a method and terminal for analyzing the arc characteristics of a fuse based on thermoelectric coupling, including determining a thermoelectric coupling equation based on the project operating conditions of the fuse; inputting the property parameters, expected short-circuit current and experimental voltage of the fuse into the thermoelectric coupling equation, and inputting a preset initial temperature value as an initial boundary parameter; determining the boundary conditions of the thermoelectric coupling equation according to the project operating conditions of the fuse; and solving the thermoelectric coupling equation with a preset calculation step size to obtain a pre-arcing time-current curve relationship diagram of the fuse. The present invention can realize accurate calculation and reliable analysis of the arc characteristics of the fuse, so that the pre-arcing time of the fuse can be effectively predicted based on the solved pre-arcing time-current curve relationship diagram, which helps to optimize the design and operation parameters of the fuse, improve the safety and stability of the power system, and reduce the losses caused by arc faults.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a method and a terminal for analyzing the arc characteristics of a fuse based on thermoelectric coupling. Background Art

[0002] In the power system, the fuse is an important safety device used to protect the circuit from faults such as overload and short circuit. When a fault occurs, the fuse needs to quickly cut off the circuit to prevent the power system from being seriously damaged, especially in large and complex power systems such as photovoltaic storage charging and testing. Fuses are widely used in power electronic equipment such as photovoltaic inverters, energy storage converters, and charging piles, playing an important protective role. However, the arc generated when the fuse is operated may cause damage to electrical equipment and safety hazards. The pre-arcing phenomenon when the fuse generates an arc has been a major research topic of long-term concern at home and abroad. Among them, the pre-arcing time-current characteristics are the main focus of everyone's attention. Therefore, the accurate calculation and analysis of the pre-arcing time-current characteristics of the fuse is crucial.

[0003] The current calculation methods of the pre-arcing time-current characteristics of fuses have some shortcomings. Traditional methods are mainly based on theoretical models or empirical formulas, which often cannot accurately reflect the complex working conditions and environmental influences in real power systems. In addition, existing methods often ignore the influence of thermoelectric coupling during the temperature rise process, resulting in a lack of accuracy and reliability in the calculation results of arc characteristics. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method and terminal for analyzing the arc characteristics of a fuse based on thermoelectric coupling, thereby improving the accuracy and reliability of the calculation of the pre-arcing time-current characteristics of the fuse.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A method for analyzing the arc characteristics of a fuse based on thermoelectric coupling comprises the following steps:

[0007] S1. Determine the thermoelectric coupling equation based on the project operating conditions of the fuse;

[0008] S2, inputting the property parameters of the fuse, the expected short-circuit current and the experimental voltage into the thermoelectric coupling equation, and inputting the preset initial temperature value as the initial boundary parameter;

[0009] S3. Determine the boundary conditions of the thermoelectric coupling equation according to the project working conditions of the fuse, specifically:

[0010] Determine the corresponding boundary condition according to the specific working condition of the fuse, if the pre-arcing time of the fuse is less than the first threshold of the heat transfer time, consider the boundary condition to be an adiabatic boundary condition;

[0011] If the pre-arcing time of the fuse is higher than the first threshold of the heat transfer time, and the heat transfer is in a steady-state heat conduction state, the boundary condition is considered to be a fixed temperature boundary condition or a fixed heat transfer boundary condition, and the steady-state heat conduction state is a state in which the temperature of each point of the fuse no longer changes with time;

[0012] S4. Preset the calculation step size, solve the thermoelectric coupling equation, and obtain the pre-arcing time-current curve relationship diagram of the fuse.

[0013] In order to solve the above technical problems, another technical solution adopted by the present invention is:

[0014] A fuse arc characteristic analysis terminal based on thermoelectric coupling 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, the steps in the above-mentioned method for analyzing the fuse arc characteristic based on thermoelectric coupling are implemented.

[0015] The beneficial effects of the present invention are: providing a fuse arc characteristic analysis method and terminal based on thermoelectric coupling, after the thermoelectric coupling equation is determined by the actual working condition of the fuse, the property parameters of the fuse, the expected short-circuit current and the experimental voltage are input into the equation, and the initial temperature value is preset as the initial boundary parameter of the thermoelectric coupling equation, and the boundary conditions determined by the actual working condition are combined to limit the thermoelectric coupling, and finally the calculation step size is preset to solve the final pre-arcing time-current curve relationship diagram of the fuse, so as to achieve accurate calculation and reliable analysis of the fuse arc characteristics, so that the pre-arcing time of the fuse can be effectively predicted according to the solved pre-arcing time-current curve relationship diagram, which is helpful to optimize the design and operation parameters of the fuse, improve the safety and stability of the power system, and reduce the losses caused by arc faults. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is an overall flow chart of a method for analyzing fuse arc characteristics based on thermoelectric coupling according to an embodiment of the present invention;

[0017] Figure 2 The present invention is a schematic structural diagram of a fuse arc characteristic analysis terminal based on thermoelectric coupling according to an embodiment of the present invention.

[0018] Description of labels:

[0019] 1. A fuse arc characteristic analysis terminal based on thermoelectric coupling; 2. Memory; 3. Processor. DETAILED DESCRIPTION

[0020] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in combination with the implementation modes and the accompanying drawings.

[0021] Please refer to Figure 1 , a method for analyzing the arc characteristics of a fuse based on thermoelectric coupling, comprising the steps of:

[0022] S1. Determine the thermoelectric coupling equation based on the project operating conditions of the fuse;

[0023] S2, inputting the property parameters of the fuse, the expected short-circuit current and the experimental voltage into the thermoelectric coupling equation, and inputting the preset initial temperature value as the initial boundary parameter;

[0024] S3. Determine the boundary conditions of the thermoelectric coupling equation according to the project working conditions of the fuse, specifically:

[0025] Determine the corresponding boundary condition according to the specific working condition of the fuse, if the pre-arcing time of the fuse is less than the first threshold of the heat transfer time, consider the boundary condition to be an adiabatic boundary condition;

[0026] If the pre-arcing time of the fuse is higher than the first threshold of the heat transfer time, and the heat transfer is in a steady-state heat conduction state, the boundary condition is considered to be a fixed temperature boundary condition or a fixed heat transfer boundary condition, and the steady-state heat conduction state is a state in which the temperature of each point of the fuse no longer changes with time;

[0027] S4. Preset the calculation step size, solve the thermoelectric coupling equation, and obtain the pre-arcing time-current curve relationship diagram of the fuse.

[0028] From the above description, it can be seen that the beneficial effects of the present invention are: providing a method for analyzing the arc characteristics of a fuse based on thermoelectric coupling, after determining the thermoelectric coupling equation through the actual working condition of the fuse, the property parameters of the fuse, the expected short-circuit current and the experimental voltage are input into the equation, and the initial temperature value is preset as the initial boundary parameter of the thermoelectric coupling equation, combined with the boundary conditions determined by the actual working condition to limit the thermoelectric coupling, and finally the calculation step size is preset to solve the final pre-arcing time-current curve relationship diagram of the fuse, thereby realizing accurate calculation and reliable analysis of the arc characteristics of the fuse, so that the pre-arcing time of the fuse can be effectively predicted according to the solved pre-arcing time-current curve relationship diagram, which is helpful to optimize the design and operation parameters of the fuse, improve the safety and stability of the power system, and reduce the losses caused by arc faults.

[0029] Furthermore, the step S1 is specifically as follows:

[0030] S11. During the pre-arcing process of the fuse, the Joule heat generated is the internal heat source, and its heat conduction equation is determined as follows (1):

[0031] (1);

[0032] Wherein, ρ is the density of the fuse, c is the specific heat capacity of the fuse, t is the temperature of any point of the fuse, λ is the thermal conductivity of the fuse, Φ is the Joule heat generated by the fuse, τ is time, and ▽ is the Laplace operator;

[0033] S12. From the relationship between Joule heat and current, we can get:

[0034] (2);

[0035] The thermoelectric coupling equation of the pre-arcing time-current characteristic of the fuse is obtained as follows (3):

[0036] (3);

[0037] Wherein, J is the current density vector flowing through the fuse, and γ is the conductivity of the fuse.

[0038] From the above description, it can be seen that the heat conduction equation is first obtained according to the relationship between the Joule heat generated by the fuse in the pre-arc worm and time, so as to determine the thermoelectric coupling equation of the pre-arc time-current characteristic of the fuse. Subsequently, the pre-arc time-current characteristic of the fuse can be accurately and reliably analyzed by solving the thermoelectric coupling equation.

[0039] Furthermore, before step S2, the following steps are also included:

[0040] S13. When it is determined that the physical property of the fuse is isotropic, the density ρ, specific heat capacity c and thermal conductivity λ are taken as constants; otherwise, analysis is performed according to corresponding dimensions.

[0041] Furthermore, the isotropy specifically means that the physical properties of the fuse will not change due to changes in direction, and the performance values ​​measured in different directions are exactly the same.

[0042] From the above description, it can be seen that before calculating the thermoelectric coupling equation, it is also possible to first determine whether the physical properties of the fuse are isotropic, thereby simplifying the subsequent calculation process according to the judgment result, ensuring the accuracy and reliability of the calculation while improving the calculation and analysis efficiency.

[0043] Furthermore, the otherwise analysis according to the corresponding dimensions is specifically as follows:

[0044] When the thermal conductivity λ is anisotropic, a set of equations for the spatial variation of λ is added to be combined with the thermoelectric coupling equation;

[0045] When the density ρ is anisotropic, a set of equations for the spatial variation of ρ is added to be combined with the thermoelectric coupling equation;

[0046] When the specific heat capacity c is anisotropic, a set of equations for c varying with space is added to be combined with the thermoelectric coupling equation.

[0047] It can be seen from the above description that when the physical properties of the fuse are anisotropic, the optimal expression of the thermoelectric coupling equation can be further determined according to which physical property parameter is anisotropic, thereby further ensuring the accuracy and reliability of the calculation.

[0048] Furthermore, the step S13 also includes:

[0049] When the spatial dimensions of the fuse are not considered, the thermoelectric coupling equation is simplified to a one-dimensional equation:

[0050] (4);

[0051] Among them, x represents a one-dimensional direction in space;

[0052] Otherwise, considering the thermoelectric coupling in three-dimensional space according to the specific spatial dimensions of the fuse, the Laplace operator ▽ in the thermoelectric coupling equation 2 t is the situation considering the changes in three-dimensional space.

[0053] From the above description, it can be seen that before calculating the thermoelectric coupling equation, it can be further determined whether to consider the specific spatial dimensions of the fuse, and the calculation of the thermoelectric coupling equation can be further simplified according to the consideration results, thereby ensuring the accuracy and reliability of the calculation while improving the calculation and analysis efficiency.

[0054] Furthermore, the step S2 is specifically as follows:

[0055] S21, inputting density ρ, specific heat capacity c, thermal conductivity λ and electrical conductivity γ into the thermoelectric coupling equation as initial parameters for analyzing the problem;

[0056] S22, using the short-circuit current and test voltage of the fuse as a basis for judging the operation of the fuse;

[0057] S23, presetting an initial temperature value and using it as an initial boundary parameter of the thermoelectric coupling equation.

[0058] From the above description, it can be seen that the various physical property parameters of the fuse are used as the initial input of the thermoelectric coupling equation. At the same time, the short-circuit current and test voltage of the fuse are used to determine whether the fuse is working. Then, the preset initial temperature value is combined to preliminarily limit the boundary of the thermoelectric coupling equation, further ensuring the accuracy and reliability of the calculation results.

[0059] Furthermore, the first threshold is one tenth.

[0060] Furthermore, the adiabatic boundary condition is specifically:

[0061] (5);

[0062] Wherein, n is the cross-sectional normal vector of the fuse;

[0063] The fixed temperature boundary conditions are specifically:

[0064] (6);

[0065] Where C0 is a constant;

[0066] The fixed heat transfer boundary conditions are specifically:

[0067] (7);

[0068] Wherein, h is the heat transfer coefficient of the fluid around the fuse, t f is the temperature of the fluid surrounding the fuse.

[0069] From the above description, it can be seen that the boundary condition of the thermoelectric coupling equation is further determined in combination with the specific working conditions of the fuse, whether it is an adiabatic boundary condition, a fixed temperature boundary condition, or a fixed heat transfer boundary condition, so as to further ensure the accuracy and reliability of the solution.

[0070] Please refer to Figure 2 A fuse arc characteristic analysis terminal based on thermoelectric coupling 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, the steps in the above-mentioned method for analyzing the arc characteristics of a fuse based on thermoelectric coupling are implemented.

[0071] From the above description, it can be seen that the beneficial effects of the present invention are: based on the same technical concept, in conjunction with the above-mentioned method for analyzing the arc characteristics of a fuse based on thermoelectric coupling, a terminal for analyzing the arc characteristics of a fuse based on thermoelectric coupling is provided. After the thermoelectric coupling equation is determined through the actual working condition of the fuse, the property parameters of the fuse, the expected short-circuit current and the experimental voltage are input into the equation, and the initial temperature value is preset as the initial boundary parameter of the thermoelectric coupling equation. The boundary conditions determined in combination with the actual working condition are used to limit the thermoelectric coupling. Finally, the calculation step size is preset to solve the final pre-arcing time-current curve relationship diagram of the fuse, thereby realizing accurate calculation and reliable analysis of the arc characteristics of the fuse, so that the pre-arcing time of the fuse can be effectively predicted according to the solved pre-arcing time-current curve relationship diagram, which is helpful to optimize the design and operation parameters of the fuse, improve the safety and stability of the power system, and reduce the losses caused by arc faults.

[0072] The present invention provides a method and terminal for analyzing the arc characteristics of a fuse based on thermoelectric coupling, which is suitable for analyzing the pre-arcing time-current characteristics of a fuse in a power system, and is described in detail below in conjunction with a specific embodiment:

[0073] Please refer to Figure 1 , Embodiment 1 of the present invention is:

[0074] A method for analyzing the arc characteristics of fuses based on thermoelectric coupling, such as Figure 1 As shown, the steps include:

[0075] S1. Determine the thermoelectric coupling equation based on the project operating conditions of the fuse.

[0076] S2. Input the property parameters of the fuse, the expected short-circuit current and the experimental voltage into the thermoelectric coupling equation, and input the preset initial temperature value as the initial boundary parameter.

[0077] S3. Determine the boundary conditions of the thermoelectric coupling equation according to the project working conditions of the fuse, specifically:

[0078] Determine the corresponding boundary condition according to the specific working condition of the fuse, if the pre-arcing time of the fuse is less than the first threshold of the heat transfer time, the boundary condition is considered to be an adiabatic boundary condition;

[0079] If the pre-arcing time of the fuse is higher than the first threshold of the heat transfer time and the heat transfer is in a steady-state thermal conduction state, the boundary condition is considered to be a fixed temperature boundary condition or a fixed heat transfer boundary condition, and the steady-state thermal conduction state is a state in which the temperature of each point of the fuse no longer changes with time.

[0080] S4. Preset the calculation step size, solve the thermoelectric coupling equation, and obtain the pre-arcing time-current curve relationship diagram of the fuse.

[0081] That is, in this embodiment, after the thermoelectric coupling equation is determined by the actual working condition of the fuse, the property parameters of the fuse, the expected short-circuit current and the experimental voltage are input into the equation, and the initial temperature value is preset as the initial boundary parameter of the thermoelectric coupling equation. The boundary conditions determined by the actual working condition are combined to limit the thermoelectric coupling, and finally the calculation step size is preset to solve the final pre-arcing time-current curve relationship diagram of the fuse, thereby realizing accurate calculation and reliable analysis of the arc characteristics of the fuse, so that the pre-arcing time of the fuse can be effectively predicted according to the solved pre-arcing time-current curve relationship diagram, which is helpful to optimize the design and operation parameters of the fuse, improve the safety and stability of the power system, and reduce the losses caused by arc faults.

[0082] Embodiment 2 of the present invention is:

[0083] A method for analyzing the arc characteristics of a fuse based on thermoelectric coupling. Based on the above embodiment 1, in this embodiment, step S1 is specifically as follows:

[0084] S11. During the pre-arcing process of the fuse, the Joule heat generated is the internal heat source, and its heat conduction equation is determined as follows (1):

[0085] (1);

[0086] Among them, ρ is the density of the fuse, c is the specific heat capacity of the fuse, t is the temperature of any point of the fuse, λ is the thermal conductivity of the fuse, Φ is the Joule heat generated by the fuse, τ is the time, and ▽ is the Laplace operator.

[0087] S12. From the relationship between Joule heat and current, we can get:

[0088] (2).

[0089] The thermoelectric coupling equation of the pre-arcing time-current characteristic of the fuse is obtained as follows (3):

[0090] (3);

[0091] Where J is the current density vector flowing through the fuse, and γ is the conductivity of the fuse.

[0092] That is, in this embodiment, the heat conduction equation is first obtained according to the relationship between the Joule heat generated by the fuse in the pre-arc circuit and time, so as to determine the thermoelectric coupling equation of the pre-arc time-current characteristic of the fuse. Subsequently, the pre-arc time-current characteristic of the fuse can be accurately and reliably analyzed by solving the thermoelectric coupling equation.

[0093] Meanwhile, in this embodiment, before step S2, the following steps are also included:

[0094] S13. When the physical properties of the fuse are judged to be isotropic, the density ρ, specific heat capacity c and thermal conductivity λ are taken as constants. Otherwise, according to the corresponding dimension analysis, specifically:

[0095] When the thermal conductivity λ is anisotropic, a set of equations for the spatial variation of λ is added to be combined with the thermoelectric coupling equation;

[0096] When the density ρ is anisotropic, a set of equations for the spatial variation of ρ is added to be combined with the thermoelectric coupling equation;

[0097] When the specific heat capacity c is anisotropic, a set of equations for c varying with space is added to be combined with the thermoelectric coupling equation.

[0098] That is, before calculating the thermoelectric coupling equation, it is also possible to first determine whether the physical properties of the fuse are isotropic, thereby simplifying the subsequent calculation process according to the judgment result, ensuring the accuracy and reliability of the calculation while improving the efficiency of calculation and analysis; at the same time, when the physical properties of the fuse are anisotropic, it is also possible to further determine the optimal expression of the thermoelectric coupling equation according to which physical property parameter is anisotropic, further ensuring the accuracy and reliability of the calculation.

[0099] In this embodiment, isotropy specifically means that the physical properties of the fuse will not change due to changes in direction, and the performance values ​​measured in different directions are exactly the same.

[0100] In addition, in this embodiment, step S13 also includes:

[0101] When the spatial dimensions of the fuse are not considered, the thermoelectric coupling equation is simplified to a one-dimensional equation:

[0102] (4);

[0103] Here, x represents a one-dimensional direction in space.

[0104] Otherwise, according to the specific spatial dimensions of the fuse, the thermoelectric coupling in the three-dimensional space is considered, and the Laplace operator in the thermoelectric coupling equation is 2 t is the situation considering the changes in three-dimensional space.

[0105] That is, before calculating the thermoelectric coupling equation, it is possible to further determine whether to consider the specific spatial dimensions of the fuse, and to further simplify the calculation of the thermoelectric coupling equation based on the consideration result, thereby ensuring the accuracy and reliability of the calculation while improving the calculation and analysis efficiency.

[0106] In this embodiment, step S2 is specifically:

[0107] S21. Input the density ρ, specific heat capacity c, thermal conductivity λ and electrical conductivity γ into the thermoelectric coupling equation as the initial input of the thermoelectric coupling equation, that is, as the initial parameters for analyzing the problem.

[0108] S22. At the same time, the short-circuit current and test voltage of the fuse are used as the basis for judging the operation of the fuse to determine whether the fuse is working.

[0109] S23, presetting an initial temperature value and using it as an initial boundary parameter of the thermoelectric coupling equation to preliminarily define the boundary of the thermoelectric coupling equation to further ensure the accuracy and reliability of the calculation results.

[0110] In this embodiment, the first threshold value defined in step S3 is one tenth, that is, the corresponding boundary condition is determined according to the specific working condition of the fuse, including that if the pre-arcing time of the fuse is less than one tenth of the heat transfer time, the boundary condition is considered to be an adiabatic boundary condition, which is specifically:

[0111] (5);

[0112] Where n is the cross-sectional normal vector of the fuse.

[0113] That is, if the pre-arcing time of the fuse is higher than one tenth of the heat transfer time, and the heat transfer is in a steady-state thermal conduction state, the boundary condition is considered to be a fixed temperature boundary condition or a fixed heat transfer boundary condition, where the steady-state thermal conduction state is a state in which the temperature of each point of the fuse no longer changes with time.

[0114] Among them, the fixed temperature boundary condition is specifically:

[0115] (6);

[0116] Where C0 is a constant;

[0117] The fixed heat transfer boundary conditions are as follows:

[0118] (7);

[0119] Where h is the heat transfer coefficient of the fluid around the fuse, t f is the temperature of the fluid surrounding the fuse.

[0120] That is, further combining the specific working conditions of the fuse to determine whether the boundary conditions of the thermoelectric coupling equation are adiabatic boundary conditions, fixed temperature boundary conditions, or fixed heat transfer boundary conditions, to further ensure the accuracy and reliability of the solution results.

[0121] It is also worth noting that in this embodiment, the short-circuit current, test voltage, initial temperature value and calculation step size can be set to specific values ​​according to the working conditions of the on-site fuse. They are mainly used as preset constant values ​​to solve the thermoelectric coupling equation and are not limited to specific values ​​here.

[0122] Please refer to Figure 2 , Embodiment 4 of the present invention is:

[0123] A fuse arc characteristic analysis terminal 1 based on thermoelectric coupling includes a memory 2, a processor 3, and a computer program stored in the memory 2 and executable on the processor 3. When the processor 3 executes the computer program, the steps of a fuse arc characteristic analysis method based on thermoelectric coupling in the above-mentioned embodiment 1 or embodiment 2 are completed.

[0124] In summary, the present invention provides a method and terminal for analyzing the arc characteristics of a fuse based on thermoelectric coupling, which have the following beneficial effects:

[0125] 1. Improved the accuracy and reliability of the calculation of the pre-arcing time-current characteristics of the fuse;

[0126] 2. Effectively predicting the pre-arcing time helps optimize the design and operating parameters of the fuse;

[0127] 3. Improve the safety and stability of the power system and reduce the losses caused by arc faults.

[0128] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for analyzing the arc characteristics of a fuse based on thermoelectric coupling, characterized in that: Includes steps: S1. Determine the thermoelectric coupling equation based on the project operating conditions of the fuse, specifically: S11. During the pre-arcing process of the fuse, the Joule heat generated is the internal heat source, and its heat conduction equation is determined as follows (1): （1）； Wherein, ρ is the density of the fuse, c is the specific heat capacity of the fuse, t is the temperature of any point of the fuse, λ is the thermal conductivity of the fuse, Φ is the Joule heat generated by the fuse, τ is time, and ▽ is the Laplace operator; S12. From the relationship between Joule heat and current, we can get: （2）； The thermoelectric coupling equation of the pre-arcing time-current characteristic of the fuse is obtained as follows (3): （3）； Wherein, J is the current density vector flowing through the fuse, and γ is the conductivity of the fuse; S2. Input the property parameters of the fuse, the expected short-circuit current and the experimental voltage into the thermoelectric coupling equation, and input the preset initial temperature value as the initial boundary parameter, specifically: S21, inputting density ρ, specific heat capacity c, thermal conductivity λ and electrical conductivity γ into the thermoelectric coupling equation as initial parameters for analyzing the problem; S22, using the short-circuit current and test voltage of the fuse as a basis for judging the operation of the fuse; S23, presetting an initial temperature value and using it as an initial boundary parameter of the thermoelectric coupling equation to preliminarily define the boundary of the thermoelectric coupling equation; S3. Determine the boundary conditions of the thermoelectric coupling equation according to the project working conditions of the fuse, specifically: Determine the corresponding boundary condition according to the specific working condition of the fuse, if the pre-arcing time of the fuse is less than the first threshold of the heat transfer time, consider the boundary condition to be an adiabatic boundary condition; If the pre-arcing time of the fuse is higher than the first threshold of the heat transfer time, and the heat transfer is in a steady-state heat conduction state, the boundary condition is considered to be a fixed temperature boundary condition or a fixed heat transfer boundary condition, and the steady-state heat conduction state is a state in which the temperature of each point of the fuse no longer changes with time; The first threshold is one tenth; The adiabatic boundary conditions are specifically: （5）； Wherein, n is the cross-sectional normal vector of the fuse; The fixed temperature boundary conditions are specifically: （6）； Where C0 is a constant; The fixed heat transfer boundary conditions are specifically: （7）； Wherein, h is the heat transfer coefficient of the fluid around the fuse, t f is the temperature of the fluid surrounding the fuse; S4, preset a calculation step length, solve the thermoelectric coupling equation, and obtain a pre-arcing time-current curve relationship diagram of the fuse; Before step S2, the following steps are also included: S13, when it is determined that the physical property of the fuse is isotropic, the density ρ, the specific heat capacity c and the thermal conductivity λ are taken as constants, otherwise, analysis is performed according to the corresponding dimensions; Otherwise, the analysis according to the corresponding dimensions is as follows: When the thermal conductivity λ is anisotropic, a set of equations for the spatial variation of λ is added to be combined with the thermoelectric coupling equation; When the density ρ is anisotropic, a set of equations for the spatial variation of ρ is added to be combined with the thermoelectric coupling equation; When the specific heat capacity c is anisotropic, a set of equations for c varying with space is added to be combined with the thermoelectric coupling equation; The expected short-circuit current, the test voltage, the preset initial temperature value and the calculation step length are all preset constant values ​​set according to the working conditions of the fuse at the site; The isotropy specifically means that the physical properties of the fuse will not change due to changes in direction, and the performance values ​​measured in different directions are exactly the same.

2. The method for analyzing fuse arc characteristics based on thermoelectric coupling according to claim 1, characterized in that: The step S13 also includes: When the spatial dimensions of the fuse are not considered, the thermoelectric coupling equation is simplified to a one-dimensional equation: （4）； Among them, x represents a one-dimensional direction in space; Otherwise, considering the thermoelectric coupling in three-dimensional space according to the specific spatial dimensions of the fuse, the Laplace operator ▽ in the thermoelectric coupling equation 2 t is the situation considering the changes in three-dimensional space.

3. A fuse arc characteristic analysis terminal based on thermoelectric coupling, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps in the method for analyzing the arc characteristics of a fuse based on thermoelectric coupling as described in any one of claims 1 to 2 are implemented.

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