Method and device for calculating critical value of arc injection energy of intermediate joint channel

Abstract

The invention provides an intermediate joint channel arc injection energy critical value calculation method and device, and the method comprises the steps: obtaining a first target parameter, calculating the injection heat of a copper net according to the first target parameter, and obtaining the first injection heat; a second target parameter is obtained, the heat conduction process of the copper net is calculated according to the first injection heat and the second target parameter, and transient temperature distribution of the copper net is obtained; determining a first damage area and a first damage depth of the copper net according to the transient distribution of the copper net, and obtaining a second damage area and a second damage depth of the copper net; and calculating a first deviation and a second deviation, and when the first deviation and the second deviation are both smaller than or equal to a first threshold value, calculating the injection energy of the intermediate joint channel arc to the copper net according to the second target parameter to obtain an energy critical value. The method solves the problem that in the prior art, a calculation method for the injected energy during explosion of the intermediate joint is lacked.

Description

Technical Field

[0001] The present invention relates to the technical field of explosion-proof of intermediate joints, and in particular to a method, a device, a computer-readable storage medium and a simulation system for calculating a critical value of arc injection energy of an intermediate joint channel. Background Art

[0002] As one of the indispensable infrastructures in modern society, high-voltage power cables provide an efficient and safe way to transmit electricity for urban power supply. In the process of urbanization and electrification, cable systems have become the first choice for reliable energy transmission.

[0003] However, there is a key weak point in the cable system, namely the cable middle joint. Past statistics show that more than 70% of cable explosion accidents occur at the middle joint. Due to its complex structure and special working environment, the middle joint is easily affected by external impurities, moisture and other factors, which can cause local electric field anomalies and discharge phenomena, which may eventually lead to cable accidents such as explosions and fires.

[0004] In cable systems, the vulnerability of cable joints is not only reflected in the frequent occurrence of failures, but more importantly, it may cause arc breakdown, causing unpredictable damage. In order to gain a deeper understanding of the arc energy release when the cable joint explodes, detailed calculations and analysis are required.

[0005] In summary, in the field of explosion-proof design of high-voltage cable intermediate joints, a method for calculating the critical value of the injection energy of the channel arc in the intermediate joint to the copper mesh is urgently needed. Summary of the invention

[0006] The main purpose of the present application is to provide a critical value calculation method, device, computer-readable storage medium and simulation system for the arc injection energy of the intermediate joint channel, so as to at least solve the problem in the prior art of lacking a method for calculating the injection energy when the intermediate joint explodes.

[0007] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a method for calculating the critical value of arc injection energy of an intermediate joint channel is provided, wherein the intermediate joint is wrapped with a copper mesh, and the method comprises: obtaining a first target parameter, and calculating the injection heat of the copper mesh according to the first target parameter to obtain a first injection heat, wherein the first target parameter at least includes the current density, current and radius of the channel arc; obtaining a second target parameter, and calculating the heat conduction process of the copper mesh according to the first injection heat and the second target parameter to obtain a transient temperature distribution of the copper mesh, wherein the second target parameter at least includes the density and specific heat capacity of the copper mesh; determining the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh to obtain a first damage area and a first damage depth, obtaining the actual damage area and actual damage depth of the copper mesh to obtain a second damage area and a second damage depth; calculating the difference between the first damage area and the second damage area to obtain a first deviation, and calculating the difference between the first damage depth and the second damage depth to obtain a second deviation, and when the first deviation and the second deviation are both less than or equal to the first threshold, calculating the injection energy of the intermediate joint channel arc to the copper mesh according to the second target parameter to obtain an energy critical value.

[0008] Optionally, the injection heat of the copper mesh is calculated according to the first target parameter to obtain a first injection heat, including: obtaining a target electric field and a preset volume, calculating the Joule heat of the channel arc injected into the copper mesh according to the target current and the preset volume, to obtain a second injection heat, wherein the target electric field is the electric field inside the copper mesh; obtaining a target current, a preset coefficient and a target radius, calculating a boundary heat source of the channel arc input into the copper mesh according to the target current, the preset coefficient and the target radius, to obtain a third injection heat, wherein the target current is the current of the channel arc, and the target radius is the radius of the channel arc; and summing the second injection heat and the third injection heat to obtain the first injection heat.

[0009] Optionally, the Joule heat injected into the copper mesh by the channel arc is calculated according to the target current and the preset volume to obtain a second injected heat, including: determining the current density of the copper mesh in the preset volume according to the preset volume to obtain the target current density; substituting the target current density, the preset volume and the target electric field into the first target formula to calculate the power to obtain the injected power: P = ∫ V lJdV; wherein l is the target electric field, V is the preset volume, P is the injection power, and J is the target current density; the injection power is substituted into the second target formula to obtain the second injection heat: Wherein, W is the second injected heat, and T is the action time of the channel arc.

[0010] Optionally, calculating the boundary heat source of the channel arc input into the copper mesh according to the target current, the preset coefficient and the target radius to obtain a third injected heat comprises: substituting the target current, the preset coefficient and the target radius into a third target formula to calculate the third injected heat: Among them, Q is the third injected heat, a is the preset coefficient, which is used to characterize the influence of the channel arc on the boundary heat source, r is the point r away from the center of the channel arc, I(t) is the target current, R(t) is the target radius, and t is the acquisition time.

[0011] Optionally, the heat conduction process of the copper mesh is calculated according to the first injected heat and the second target parameter to obtain the transient temperature distribution of the copper mesh, including: obtaining a target density, a target specific heat capacity, a target heat transfer coefficient and a first target temperature, wherein the target density is the density of the copper mesh, the target specific heat capacity is the specific heat capacity of the copper mesh, the target heat transfer coefficient is the heat transfer coefficient of the copper mesh, the target electrical conductivity is the electrical conductivity of the copper mesh, and the first target temperature is the initial temperature of the copper mesh; constructing a heat conduction equation according to the target density, the target specific heat capacity, the target heat transfer coefficient, the target electrical conductivity and the first target temperature: Wherein, ρ is the target density, C is the target specific heat capacity, dθ is the temperature change, ▽ is the gradient operator, k is the target heat transfer coefficient, θ is the initial temperature, and M satisfies M=Q+W; obtain the target mass and target latent heat, the target mass is the mass of the copper mesh, and the target latent heat is the latent heat of the phase change of the copper mesh; construct the phase change equation according to the target mass and the target latent heat: Wherein, m is the target mass, and L is the target latent heat; the heat conduction equation and the phase change equation are simultaneously solved to obtain the transient temperature distribution of the copper mesh.

[0012] Optionally, the damage area and damage depth of the copper mesh are determined according to the transient distribution of the copper mesh to obtain a first damage area and a first damage depth, including: constructing a three-dimensional rectangular coordinate system with an arbitrary position of the copper mesh as the origin, and traversing the temperature of each position of the copper mesh in the three-dimensional rectangular coordinate system to obtain a second target temperature; when the second target temperature is greater than or equal to a second threshold, the corresponding position is determined as a damaged position, and when the second target temperature is less than the second threshold, the corresponding position is determined as an undamaged position; and determining the first damage area and the first damage depth according to the damaged position and the undamaged position.

[0013] Optionally, after calculating the difference between the first damage area and the second damage area to obtain the first deviation, and calculating the difference between the first damage depth and the second damage depth to obtain the second deviation, the method further includes: when the first deviation or the second deviation is greater than the first threshold, increasing the preset coefficient with a preset gradient and recalculating the first deviation and the second deviation until both the first deviation and the second deviation are less than or equal to the first threshold.

[0014] According to another aspect of the present application, a device for calculating the critical value of arc injection energy of an intermediate joint channel is provided, wherein the intermediate joint is wrapped with a copper mesh, and the device comprises: a first acquisition unit for acquiring a first target parameter, and calculating the injection heat of the copper mesh according to the first target parameter to obtain a first injection heat, wherein the first target parameter at least includes the current density, current and radius of the channel arc; a second acquisition unit for acquiring a second target parameter, and calculating the heat conduction process of the copper mesh according to the first injection heat and the second target parameter to obtain a transient temperature distribution of the copper mesh, wherein the second target parameter at least includes the density and specific heat capacity of the copper mesh; a first calculation unit for calculating the critical value of arc injection energy of an intermediate joint channel; and a second calculation unit for calculating the critical value of arc injection energy of an intermediate joint channel. a calculation unit for determining the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh, obtaining a first damage area and a first damage depth, obtaining an actual damage area and an actual damage depth of the copper mesh, obtaining a second damage area and a second damage depth; a second calculation unit for calculating the difference between the first damage area and the second damage area to obtain a first deviation, calculating the difference between the first damage depth and the second damage depth to obtain a second deviation, and when the first deviation and the second deviation are both less than or equal to the first difference, calculating the injection energy of the arc of the intermediate joint channel into the copper mesh according to the second target parameter to obtain an energy critical value.

[0015] According to another aspect of the present application, a computer-readable storage medium is provided, wherein the computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute any one of the methods described.

[0016] According to another aspect of the present application, a simulation system is provided, comprising: one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include methods for executing any one of the described methods.

[0017] By applying the technical solution of the present application, in the critical value calculation method of the arc injection energy of the intermediate joint channel, first, a first target parameter is obtained, and the injection heat of the copper mesh is calculated according to the first target parameter to obtain the first injection heat, and the first target parameter at least includes the current density, current and radius of the channel arc; then, a second target parameter is obtained, and the heat conduction process of the copper mesh is calculated according to the first injection heat and the second target parameter to obtain the transient temperature distribution of the copper mesh, and the second target parameter at least includes the density and specific heat capacity of the copper mesh; then, the damage area and damage depth of the copper mesh are determined according to the transient distribution of the copper mesh to obtain the first damage area and the first damage depth, and the actual damage area and actual damage depth of the copper mesh are obtained to obtain the second damage area and the second damage depth; finally, the difference between the first damage area and the second damage area is calculated to obtain the first deviation, and the difference between the first damage depth and the second damage depth is calculated to obtain the second deviation. When the first deviation and the second deviation are both less than or equal to the first threshold, the injection energy of the intermediate joint channel arc to the copper mesh is calculated according to the second target parameter to obtain the energy critical value. This application adopts a numerical simulation method, based on a numerical model, to calculate the heat source according to the measured channel arc of the broken-down intermediate joint, and to calculate the estimated damage area and damage depth of the copper mesh in combination with the phase change effect under the high temperature of the copper mesh, and to compare the actual damage area and actual damage depth, and to determine that the channel arc injection energy of the numerical model is the critical value of the channel arc injection energy when the deviation is within the allowable range. This method solves the problem of the lack of a method for calculating the injection energy when the intermediate joint explodes in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A hardware structure block diagram of a mobile terminal according to a method for calculating a critical value of arc injection energy of an intermediate joint channel provided in an embodiment of the present application is shown;

[0019] Figure 2 A schematic flow chart of a method for calculating a critical value of arc injection energy of an intermediate joint channel provided in accordance with an embodiment of the present application is shown;

[0020] Figure 3 A structural block diagram of a device for calculating a critical value of arc injection energy of an intermediate joint channel provided according to an embodiment of the present application is shown.

[0021] The above drawings include the following reference numerals:

[0022] 102, processor; 104, memory; 106, transmission device; 108, input and output devices. DETAILED DESCRIPTION

[0023] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0025] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0026] As introduced in the background technology, in the prior art, the field of explosion-proof design of intermediate joints of high-voltage cables urgently needs a method for calculating the critical value of the injection energy of the channel arc in the intermediate joint to the copper mesh. In order to solve the problem that the prior art lacks a method for calculating the injection energy when the intermediate joint explodes, the embodiments of the present application provide a method, device, computer-readable storage medium and simulation system for calculating the critical value of the injection energy of the channel arc in the intermediate joint.

[0027] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0028] The method embodiments provided in the embodiments of the present application can be executed in a mobile terminal, a computer terminal or a similar computing device. Taking running on a mobile terminal as an example, Figure 1 1 is a hardware structure block diagram of a mobile terminal for calculating a critical value of arc injection energy of an intermediate joint channel according to an embodiment of the present invention. Figure 1 As shown, the mobile terminal may include one or more ( Figure 1Only one is shown in the figure) a processor 102 (the processor 102 may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA) and a memory 104 for storing data, wherein the mobile terminal may also include a transmission device 106 and an input / output device 108 for communication functions. It can be understood by those skilled in the art that Figure 1 The structure shown is only for illustration and does not limit the structure of the mobile terminal. Figure 1 More or fewer components as shown, or with Figure 1 Different configurations are shown.

[0029] The memory 104 can be used to store computer programs, for example, software programs and modules of application software, such as the computer program corresponding to the display method of device information in the embodiment of the present invention. The processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, that is, the above method is implemented. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include a memory remotely arranged relative to the processor 102, and these remote memories can be connected to the mobile terminal via a network. Examples of the above-mentioned network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof. The transmission device 106 is used to receive or send data via a network. The above-mentioned specific examples of the network may include a wireless network provided by a communication provider of the mobile terminal. In one example, the transmission device 106 includes a network adapter (Network Interface Controller, referred to as NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission device 106 may be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0030] In this embodiment, a method for calculating the critical value of the arc injection energy of the intermediate joint channel running on a mobile terminal, a computer terminal or a similar computing device is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0031] Figure 2 1 is a flow chart of a method for calculating a critical value of arc injection energy of an intermediate joint channel according to an embodiment of the present application. Figure 2As shown, the method comprises the following steps:

[0032] Step S201, obtaining a first target parameter, and calculating the injection heat of the copper mesh according to the first target parameter to obtain a first injection heat, wherein the first target parameter at least includes a current density, a current and a radius of a channel arc;

[0033] In the specific implementation, the relevant parameters of the copper mesh are first obtained and a numerical model is constructed, which includes constructing a geometric model in the numerical model according to the collective structure of the copper mesh to ensure that the collective model is consistent with the actual sample. In addition, the material parameters of the actual sample are consistent with the numerical model.

[0034] Specifically, the above numerical model is used to calculate the Joule heat effect and arc heat transfer effect in the heat source received by the copper mesh based on relevant parameters of the channel arc, namely the above first target parameters, to obtain the above first injected heat.

[0035] Step S202, obtaining a second target parameter, calculating the heat conduction process of the copper mesh according to the first injected heat and the second target parameter to obtain a transient temperature distribution of the copper mesh, wherein the second target parameter at least includes a density and a specific heat capacity of the copper mesh;

[0036] Specifically, in order to simulate the damage of the copper mesh caused by the energy injected by the channel arc during the breakdown of the intermediate joint, in addition to considering the heat injected into the copper mesh by the channel current of the intermediate joint, the heat conduction and phase change effect in the copper mesh must also be considered. Specifically, through the above numerical model, based on the material parameters of the copper mesh, that is, the above second target parameters, the temperature distribution of the copper mesh during the heat conduction process in the copper mesh is calculated to obtain the above transient temperature distribution of the copper mesh.

[0037] Step S203, determining the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh, obtaining a first damage area and a first damage depth, obtaining an actual damage area and an actual damage depth of the copper mesh, and obtaining a second damage area and a second damage depth;

[0038] Specifically, the above numerical model is based on the above copper mesh transient distribution, combined with the preset copper mesh phase change temperature threshold, the damage area and damage depth of the copper mesh can be determined, that is, the part whose temperature exceeds the phase change temperature threshold is determined to be damaged, and the above first damage area and the above first damage depth are obtained. Then the damage area and damage depth of the actual sample are measured to obtain the above second damage area and second damage depth.

[0039] Step S204, calculate the difference between the first damage area and the second damage area to obtain a first deviation, calculate the difference between the first damage depth and the second damage depth to obtain a second deviation, and when the first deviation and the second deviation are both less than or equal to the first threshold, calculate the injection energy of the arc of the intermediate joint channel into the copper mesh according to the second target parameter to obtain an energy critical value.

[0040] Specifically, the damage area and damage depth are determined as damage characteristic parameters. Due to the randomness of the intermediate joint breakdown process, the same injection energy may cause different damage to the copper mesh. The present application is set to allow the calculated damage characteristic parameters to be less than the first threshold value (10%) when the deviation between the damage characteristic parameters and the actual sample is less than the above-mentioned first threshold value (10%). At this time, the injection heat of the numerical model is determined, that is, the critical value of the channel arc injection energy is obtained, that is, the above-mentioned energy critical value, and the specific formula is:

[0041] E = ∫∫∫CρΔTdV;

[0042] Among them, E is the above-mentioned energy critical value, C is the specific heat capacity of the copper mesh, ρ is the density of the copper mesh, and ΔT is the transient temperature rise of the numerical model.

[0043] Through this embodiment, first, a first target parameter is obtained, and the injection heat of the copper mesh is calculated according to the first target parameter to obtain the first injection heat, and the first target parameter at least includes the current density, current and radius of the channel arc; then, a second target parameter is obtained, and the heat conduction process of the copper mesh is calculated according to the first injection heat and the second target parameter to obtain the transient temperature distribution of the copper mesh, and the second target parameter at least includes the density and specific heat capacity of the copper mesh; thereafter, the damage area and damage depth of the copper mesh are determined according to the transient distribution of the copper mesh to obtain the first damage area and the first damage depth, and the actual damage area and actual damage depth of the copper mesh are obtained to obtain the second damage area and the second damage depth; finally, the difference between the first damage area and the second damage area is calculated to obtain the first deviation, and the difference between the first damage depth and the second damage depth is calculated to obtain the second deviation. When the first deviation and the second deviation are both less than or equal to the first threshold value, the injection energy of the intermediate joint channel arc to the copper mesh is calculated according to the second target parameter to obtain the energy critical value. This application adopts a numerical simulation method, based on a numerical model, to calculate the heat source according to the measured channel arc of the broken-down intermediate joint, and to calculate the estimated damage area and damage depth of the copper mesh in combination with the phase change effect under the high temperature of the copper mesh, and to compare the actual damage area and actual damage depth, and to determine that the channel arc injection energy of the numerical model is the critical value of the channel arc injection energy when the deviation is within the allowable range. This method solves the problem of the lack of a method for calculating the injection energy when the intermediate joint explodes in the prior art.

[0044] In order to calculate the first input energy, in an optional implementation, the step S201 includes:

[0045] Step S2011, obtaining a target electric field and a preset volume, calculating the Joule heat injected by the channel arc into the copper mesh according to the target current and the preset volume, and obtaining a second injected heat, wherein the target electric field is the electric field inside the copper mesh;

[0046] Specifically, under the influence of the channel arc injection energy of the middle joint, the copper mesh receives heat sources including Joule heating effect and arc heat transfer effect. The Joule heating effect can be calculated through electrothermal coupling, that is, the electric field l inside the copper mesh is calculated through a numerical model to obtain the above-mentioned target electric field, and the Joule heat generated by the channel arc injection energy is calculated within a given volume, that is, the above-mentioned preset volume to obtain the above-mentioned second injection heat.

[0047] Step S2012, obtaining a target current, a preset coefficient and a target radius, and calculating a boundary heat source of the channel arc input into the copper mesh according to the target current, the preset coefficient and the target radius to obtain a third injected heat, wherein the target current is the current of the channel arc, and the target radius is the radius of the channel arc;

[0048] Specifically, on the other hand, based on the heat transfer effect of the channel arc, that is, the calculation of the boundary heat source injected by the channel arc can be simulated by the boundary heat source of the traditional physical model of injected energy, specifically, the current value, time, distance from the center of the channel arc and the radius of the channel arc are calculated to obtain the above-mentioned third injected heat.

[0049] Step S2013, summing the second injected heat and the third injected heat to obtain the first injected heat.

[0050] Specifically, the second injected heat amount and the third injected heat amount are summed to obtain the total injected heat of the numerical model, that is, the first injected heat amount.

[0051] In order to obtain the second injected heat, in an optional implementation, the step S2011 includes:

[0052] Step S20111, determining the current density of the copper mesh within the preset volume according to the preset volume to obtain a target current density;

[0053] Specifically, based on electrothermal coupling, the electric field l inside the copper mesh is calculated, and then the current density J in a given volume V is calculated to obtain the above target current density.

[0054] Step S20112, substituting the target current density, the preset volume and the target electric field into the first target formula to calculate the power, and obtaining the injected power:

[0055] P = ∫ V lJdV;

[0056] Wherein, l is the target electric field, V is the preset volume, P is the injection power, and J is the target current density;

[0057] Specifically, in combination with the target current density J, the preset volume V and the target electric field l, the thermal power P of Joule heat, ie, the injection power, can be calculated.

[0058] Step S20113, substituting the above injection power into the second target formula to obtain the above second injection heat:

[0059]

[0060] Wherein, W is the second injected heat, and T is the action time of the channel arc.

[0061] Specifically, the work done by Joule heat is obtained by integrating the power P on a time scale, that is, the second injected heat W is obtained.

[0062] In order to calculate the third injected heat, in an optional implementation, the step S2012 includes:

[0063] Step S20121, substituting the target current, the preset coefficient and the target radius into a third target formula to calculate the third injected heat:

[0064]

[0065] Among them, Q is the above-mentioned third injected heat, a is the above-mentioned preset coefficient, which is used to characterize the influence of the above-mentioned channel arc on the above-mentioned boundary heat source, r is the point r away from the center of the above-mentioned channel arc, I(t) is the above-mentioned target current, R(t) is the above-mentioned target radius, and t is the acquisition time.

[0066] Specifically, for the boundary heat source injected by the channel arc, only a preliminary calculation is performed here to obtain an estimated value, which allows for deviations, and then the calculation of the third injected heat can be achieved based on the above formula.

[0067] In a specific implementation, the coefficient a is a comprehensive consideration of the contribution of electrons to the boundary heat source, and in the traditional boundary heat source formula, its value is 10. This coefficient is positively correlated with the boundary heat source, and by adjusting the value of coefficient a, the boundary heat source injected by the channel arc can be changed, and the damage characteristic parameters can be adjusted.

[0068] In order to calculate the transient temperature distribution of the copper mesh, in an optional implementation, the step S202 includes:

[0069] Step S2021, obtaining a target density, a target specific heat capacity, a target heat transfer coefficient and a first target temperature, wherein the target density is the density of the copper mesh, the target specific heat capacity is the specific heat capacity of the copper mesh, the target heat transfer coefficient is the heat transfer coefficient of the copper mesh, the target electrical conductivity is the electrical conductivity of the copper mesh, and the first target temperature is the initial temperature of the copper mesh;

[0070] In the embodiments of the present application, in order to ensure the accuracy of the above numerical model, in addition to considering the heat conduction of the injected heat in the copper mesh, the present application also introduces the phase change effect of the copper mesh. For the simulation of the phase change effect of the copper mesh, the present application adopts the reduced specific heat capacity method.

[0071] Specifically, the density ρ, specific heat capacity C, heat transfer coefficient k, and initial temperature θ of the copper mesh are obtained.

[0072] In a specific implementation, obtaining the above target specific heat capacity includes:

[0073] Substitute the above temperature change, the above specific heat capacity and the latent heat of melting into the fourth objective formula to calculate the equivalent specific heat capacity:

[0074]

[0075] Among them, C eq_melt is the above-mentioned equivalent specific heat capacity, L is the above-mentioned latent heat of fusion, C is the above-mentioned specific heat capacity, and dθ is the above-mentioned temperature change.

[0076] Furthermore, when the copper mesh is less than θ melt -Δθ (close to the melting point but not yet reached), the same specific heat capacity is used. melt -Δθ increases to θ melt (melting point), the additional heat required to melt the copper mesh needs to be considered. eq_melt Replace the original specific heat capacity and introduce the latent heat of melting.

[0077] Step S2022, constructing a heat conduction equation according to the target density, the target specific heat capacity, the target heat transfer coefficient, the target electrical conductivity and the first target temperature:

[0078]

[0079] Wherein, ρ is the target density, C is the target specific heat capacity, dθ is the temperature change, ▽ is the gradient operator, k is the target heat transfer coefficient, θ is the initial temperature, and M satisfies M=Q+W;

[0080] Specifically, the heat conduction equation is constructed by simulating the heat conduction of the input heat in the copper mesh based on the target density, the target specific heat capacity, the target heat transfer coefficient, the target electrical conductivity and the first target temperature through a numerical model.

[0081] Step S2023, obtaining a target mass and a target latent heat, wherein the target mass is the mass of the copper mesh, and the target latent heat is the latent heat of phase change of the copper mesh;

[0082] Specifically, the target mass m and the target latent heat L are acquired.

[0083] Step S2024, constructing a phase change equation according to the target mass and the target latent heat:

[0084]

[0085] Wherein, m is the above-mentioned target mass, L is the above-mentioned target latent heat;

[0086] Specifically, based on the target mass and the target latent heat, the phase change effect caused by the input heat in the copper mesh is simulated through a numerical model to construct the phase change equation.

[0087] Step S2025, the heat conduction equation and the phase change equation are simultaneously solved to obtain the transient temperature distribution of the copper mesh.

[0088] Specifically, the above heat conduction equation and the above phase change equation are simultaneously solved to obtain the changed temperature at any position of the copper mesh and the above transient temperature distribution of the copper mesh.

[0089] In order to determine the first damage area and the first damage depth, in an optional implementation, the step S203 includes:

[0090] Step S2031, constructing a three-dimensional rectangular coordinate system with any position of the copper mesh as the origin, and traversing the temperature of each position of the copper mesh in the three-dimensional rectangular coordinate system to obtain a second target temperature;

[0091] Specifically, a coordinate system is established at the location of the copper mesh through a numerical model, the coordinates of the copper mesh in the coordinate system are determined, and each point is traversed to determine its corresponding changed temperature to obtain the above-mentioned second target temperature.

[0092] Step S2032, when the second target temperature is greater than or equal to the second threshold, the corresponding position is determined as a damaged position; when the second target temperature is less than the second threshold, the corresponding position is determined as an undamaged position;

[0093] Specifically, each point in the copper network is traversed, and when the second target temperature is greater than or equal to the second threshold, the corresponding position is determined as a damaged position; when the second target temperature is less than the second threshold, the corresponding position is determined as an undamaged position.

[0094] Step S2033, determining the first damage area and the first damage depth according to the damaged position and the undamaged position.

[0095] Specifically, the first damage area is formed according to the portion of all the damaged positions located at the contour of the copper mesh, and then all damaged parts are dug out and the maximum value of the depth change is compared to obtain the first damage depth.

[0096] In order to ensure the accuracy of the numerical model, in an optional implementation, after calculating the difference between the first damage area and the second damage area to obtain the first deviation, and calculating the difference between the first damage depth and the second damage depth to obtain the second deviation, the method further includes:

[0097] Step S301, when the first deviation or the second deviation is greater than the first threshold, increase the preset coefficient with a preset gradient and recalculate the first deviation and the second deviation until both the first deviation and the second deviation are less than or equal to the first threshold.

[0098] Specifically, when the damage characteristic parameter in the numerical model is smaller than the damage characteristic parameter of the actual sample, the preset coefficient is increased, the gradient is set to 1, and the damage characteristic parameter is recalculated each time the preset coefficient changes.

[0099] Furthermore, if the damage characteristic parameter in the numerical model is greater than the damage characteristic parameter of the actual sample, the above preset coefficient is reduced, and the gradient is set to 1. Each time the preset coefficient changes, the above damage characteristic parameter is recalculated.

[0100] The preset coefficients are adjusted repeatedly until the above damage characteristics are consistent, and it is determined that the simulation accuracy of the numerical model for the effect of the arc injection energy of the middle joint channel on the copper mesh meets the requirements.

[0101] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0102] The embodiment of the present application also provides a critical value calculation device for the arc injection energy of the intermediate joint channel. It should be noted that the critical value calculation device for the arc injection energy of the intermediate joint channel of the embodiment of the present application can be used to execute the critical value calculation method for the arc injection energy of the intermediate joint channel provided by the embodiment of the present application. The device is used to implement the above-mentioned embodiments and preferred implementation modes, and the descriptions that have been made will not be repeated. As used below, the term "module" can implement a combination of software and / or hardware of a predetermined function. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware is also possible and conceived.

[0103] The following is an introduction to the critical value calculation device for the arc injection energy of the intermediate joint channel provided in an embodiment of the present application.

[0104] Figure 3 1 is a structural block diagram of a device for calculating the critical value of arc injection energy of an intermediate joint channel according to an embodiment of the present application. Figure 3 As shown, the device comprises:

[0105] A first acquisition unit 10 is used to acquire a first target parameter, and calculate the injection heat of the copper mesh according to the first target parameter to obtain a first injection heat, wherein the first target parameter at least includes a current density, a current and a radius of the channel arc;

[0106] In the specific implementation, the relevant parameters of the copper mesh are first obtained and a numerical model is constructed, which includes constructing a geometric model in the numerical model according to the collective structure of the copper mesh to ensure that the collective model is consistent with the actual sample. In addition, the material parameters of the actual sample are consistent with the numerical model.

[0107] Specifically, the above numerical model is used to calculate the Joule heat effect and arc heat transfer effect in the heat source received by the copper mesh based on relevant parameters of the channel arc, namely the above first target parameters, to obtain the above first injected heat.

[0108] A second acquisition unit 20 is used to acquire a second target parameter, and calculate the heat conduction process of the copper mesh according to the first injected heat and the second target parameter to obtain a transient temperature distribution of the copper mesh, wherein the second target parameter at least includes a density and a specific heat capacity of the copper mesh;

[0109] Specifically, in order to simulate the damage of the copper mesh caused by the energy injected by the channel arc during the breakdown of the intermediate joint, in addition to considering the heat injected into the copper mesh by the channel current of the intermediate joint, the heat conduction and phase change effect in the copper mesh must also be considered. Specifically, through the above numerical model, based on the material parameters of the copper mesh, that is, the above second target parameters, the temperature distribution of the copper mesh during the heat conduction process in the copper mesh is calculated to obtain the above transient temperature distribution of the copper mesh.

[0110] The first calculation unit 30 is used to determine the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh, obtain the first damage area and the first damage depth, obtain the actual damage area and the actual damage depth of the copper mesh, and obtain the second damage area and the second damage depth;

[0111] Specifically, the above numerical model is based on the above copper mesh transient distribution, combined with the preset copper mesh phase change temperature threshold, the damage area and damage depth of the copper mesh can be determined, that is, the part whose temperature exceeds the phase change temperature threshold is determined to be damaged, and the above first damage area and the above first damage depth are obtained. Then the damage area and damage depth of the actual sample are measured to obtain the above second damage area and second damage depth.

[0112] The second calculation unit 40 is used to calculate the difference between the first damage area and the second damage area to obtain a first deviation, and calculate the difference between the first damage depth and the second damage depth to obtain a second deviation. When the first deviation and the second deviation are both less than or equal to the first threshold, the injection energy of the arc of the intermediate joint channel into the copper mesh is calculated according to the second target parameter to obtain an energy critical value.

[0113] Specifically, the damage area and damage depth are determined as damage characteristic parameters. Due to the randomness of the intermediate joint breakdown process, the same injection energy may cause different damage to the copper mesh. The present application is set to allow the calculated damage characteristic parameters to be less than the first threshold value (10%) when the deviation between the damage characteristic parameters and the actual sample is less than the above-mentioned first threshold value (10%). At this time, the injection heat of the numerical model is determined, that is, the critical value of the channel arc injection energy is obtained, that is, the above-mentioned energy critical value, and the specific formula is:

[0114] E = ∫∫∫CρΔTdV;

[0115] Among them, E is the above-mentioned energy critical value, C is the specific heat capacity of the copper mesh, ρ is the density of the copper mesh, and ΔT is the transient temperature rise of the numerical model.

[0116] Through this embodiment, the first acquisition unit acquires the first target parameter, calculates the injected heat of the copper mesh according to the first target parameter to obtain the first injected heat, and the first target parameter at least includes the current density, current and radius of the channel arc; the second acquisition unit acquires the second target parameter, calculates the heat conduction process of the copper mesh according to the first injected heat and the second target parameter, and obtains the transient temperature distribution of the copper mesh, and the second target parameter at least includes the density and specific heat capacity of the copper mesh; the first calculation unit determines the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh, obtains the first damage area and the first damage depth, acquires the actual damage area and the actual damage depth of the copper mesh, and obtains the second damage area and the second damage depth; the second calculation unit calculates the difference between the first damage area and the second damage area to obtain the first deviation, calculates the difference between the first damage depth and the second damage depth to obtain the second deviation, and when the first deviation and the second deviation are both less than or equal to the first threshold, calculates the injection energy of the intermediate joint channel arc to the copper mesh according to the second target parameter to obtain the energy critical value. This application adopts a numerical simulation method, based on a numerical model, to calculate the heat source according to the measured channel arc of the broken-down intermediate joint, and to calculate the estimated damage area and damage depth of the copper mesh in combination with the phase change effect under the high temperature of the copper mesh, and to compare the actual damage area and actual damage depth, and to determine that the channel arc injection energy of the numerical model is the critical value of the channel arc injection energy when the deviation is within the allowable range. This method solves the problem of the lack of a method for calculating the injection energy when the intermediate joint explodes in the prior art.

[0117] In order to calculate the first input energy, in an optional implementation manner, the first acquisition unit includes:

[0118] A first acquisition module is used to acquire a target electric field and a preset volume, and calculate the Joule heat injected by the channel arc into the copper mesh according to the target current and the preset volume to obtain a second injected heat, wherein the target electric field is the electric field inside the copper mesh;

[0119] Specifically, under the influence of the channel arc injection energy of the middle joint, the copper mesh receives heat sources including Joule heating effect and arc heat transfer effect. The Joule heating effect can be calculated through electrothermal coupling, that is, the electric field l inside the copper mesh is calculated through a numerical model to obtain the above-mentioned target electric field, and the Joule heat generated by the channel arc injection energy is calculated within a given volume, that is, the above-mentioned preset volume to obtain the above-mentioned second injection heat.

[0120] A second acquisition module is used to acquire a target current, a preset coefficient and a target radius, and calculate the boundary heat source of the channel arc input into the copper mesh according to the target current, the preset coefficient and the target radius to obtain a third injected heat, wherein the target current is the current of the channel arc, and the target radius is the radius of the channel arc;

[0121] Specifically, on the other hand, based on the heat transfer effect of the channel arc, that is, the calculation of the boundary heat source injected by the channel arc can be simulated by the boundary heat source of the traditional physical model of injected energy, specifically, the current value, time, distance from the center of the channel arc and the radius of the channel arc are calculated to obtain the above-mentioned third injected heat.

[0122] The first calculation unit is used to sum the second injected heat and the third injected heat to obtain the first injected heat.

[0123] Specifically, the second injected heat amount and the third injected heat amount are summed to obtain the total injected heat of the numerical model, that is, the first injected heat amount.

[0124] In order to obtain the second injected heat, in an optional implementation, the first acquisition module includes:

[0125] A first calculation submodule, used for determining the current density of the copper mesh within the preset volume according to the preset volume to obtain a target current density;

[0126] Specifically, based on electrothermal coupling, the electric field l inside the copper mesh is calculated, and then the current density J in a given volume V is calculated to obtain the above target current density.

[0127] The second calculation submodule is used to substitute the target current density, the preset volume and the target electric field into the first target formula to calculate the power and obtain the injected power:

[0128] P = ∫ V lJdV;

[0129] Wherein, l is the target electric field, V is the preset volume, P is the injection power, and J is the target current density;

[0130] Specifically, in combination with the target current density J, the preset volume V and the target electric field l, the thermal power P of Joule heat, ie, the injection power, can be calculated.

[0131] The second calculation submodule is used to substitute the injection power into the second target formula to obtain the second injection heat:

[0132]

[0133] Wherein, W is the second injected heat, and T is the action time of the channel arc.

[0134] Specifically, the work done by Joule heat is obtained by integrating the power P on a time scale, that is, the second injected heat W is obtained.

[0135] In order to calculate the third injected heat, in an optional implementation, the second acquisition module includes:

[0136] The third calculation submodule is used to substitute the target current, the preset coefficient and the target radius into a third target formula to calculate the third injected heat:

[0137]

[0138] Among them, Q is the above-mentioned third injected heat, a is the above-mentioned preset coefficient, which is used to characterize the influence of the above-mentioned channel arc on the above-mentioned boundary heat source, r is the point r away from the center of the above-mentioned channel arc, I(t) is the above-mentioned target current, R(t) is the above-mentioned target radius, and t is the acquisition time.

[0139] Specifically, for the boundary heat source injected by the channel arc, only a preliminary calculation is performed here to obtain an estimated value, which allows for deviations, and then the calculation of the third injected heat can be achieved based on the above formula.

[0140] In a specific implementation, the coefficient a is a comprehensive consideration of the contribution of electrons to the boundary heat source, and in the traditional boundary heat source formula, its value is 10. This coefficient is positively correlated with the boundary heat source, and by adjusting the value of coefficient a, the boundary heat source injected by the channel arc can be changed, and the damage characteristic parameters can be adjusted.

[0141] In order to calculate the transient temperature distribution of the copper mesh, in an optional implementation, the second acquisition unit includes:

[0142] A third acquisition module is used to acquire a target density, a target specific heat capacity, a target heat transfer coefficient and a first target temperature, wherein the target density is the density of the copper mesh, the target specific heat capacity is the specific heat capacity of the copper mesh, the target heat transfer coefficient is the heat transfer coefficient of the copper mesh, the target electrical conductivity is the electrical conductivity of the copper mesh, and the first target temperature is the initial temperature of the copper mesh;

[0143] In the embodiments of the present application, in order to ensure the accuracy of the above numerical model, in addition to considering the heat conduction of the injected heat in the copper mesh, the present application also introduces the phase change effect of the copper mesh. For the simulation of the phase change effect of the copper mesh, the present application adopts the reduced specific heat capacity method.

[0144] Specifically, the density ρ, specific heat capacity C, heat transfer coefficient k, and initial temperature θ of the copper mesh are obtained.

[0145] In a specific implementation, obtaining the above target specific heat capacity includes:

[0146] Substitute the above temperature change, the above specific heat capacity and the latent heat of melting into the fourth objective formula to calculate the equivalent specific heat capacity:

[0147]

[0148] Among them, C eq_melt is the above-mentioned equivalent specific heat capacity, L is the above-mentioned latent heat of fusion, C is the above-mentioned specific heat capacity, and dθ is the above-mentioned temperature change.

[0149] Furthermore, when the copper mesh is less than θ melt -Δθ (close to the melting point but not yet reached), the same specific heat capacity is used. melt -Δθ increases to θ melt (melting point), the additional heat required to melt the copper mesh needs to be considered. eq_melt Replace the original specific heat capacity and introduce the latent heat of melting.

[0150] The second calculation module is used to construct a heat conduction equation according to the target density, the target specific heat capacity, the target heat transfer coefficient, the target conductivity and the first target temperature:

[0151]

[0152] Wherein, ρ is the target density, C is the target specific heat capacity, dθ is the temperature change, ▽ is the gradient operator, k is the target heat transfer coefficient, θ is the initial temperature, and M satisfies M=Q+W;

[0153] Specifically, the heat conduction equation is constructed by simulating the heat conduction of the input heat in the copper mesh based on the target density, the target specific heat capacity, the target heat transfer coefficient, the target electrical conductivity and the first target temperature through a numerical model.

[0154] A fourth acquisition module is used to acquire a target mass and a target latent heat, wherein the target mass is the mass of the copper mesh, and the target latent heat is the latent heat of a phase change of the copper mesh;

[0155] Specifically, the target mass m and the target latent heat L are acquired.

[0156] The third calculation module is used to construct a phase change equation according to the target mass and the target latent heat:

[0157]

[0158] Wherein, m is the above-mentioned target mass, L is the above-mentioned target latent heat;

[0159] Specifically, based on the target mass and the target latent heat, the phase change effect caused by the input heat in the copper mesh is simulated through a numerical model to construct the phase change equation.

[0160] The fourth calculation module is used to simultaneously solve the above heat conduction equation and the above phase change equation to obtain the transient temperature distribution of the copper mesh.

[0161] Specifically, the above heat conduction equation and the above phase change equation are simultaneously solved to obtain the changed temperature at any position of the copper mesh and the above transient temperature distribution of the copper mesh.

[0162] In order to determine the first damage area and the first damage depth, in an optional implementation manner, the first calculation unit includes:

[0163] A first determination module is used to construct a three-dimensional rectangular coordinate system with any position of the copper mesh as the origin, and traverse the temperature of each position of the copper mesh in the three-dimensional rectangular coordinate system to obtain a second target temperature;

[0164] Specifically, a coordinate system is established at the location of the copper mesh through a numerical model, the coordinates of the copper mesh in the coordinate system are determined, and each point is traversed to determine its corresponding changed temperature to obtain the above-mentioned second target temperature.

[0165] A second determination module, configured to determine the corresponding position as a damaged position when the second target temperature is greater than or equal to a second threshold, and to determine the corresponding position as an undamaged position when the second target temperature is less than the second threshold;

[0166] Specifically, each point in the copper network is traversed, and when the second target temperature is greater than or equal to the second threshold, the corresponding position is determined as a damaged position; when the second target temperature is less than the second threshold, the corresponding position is determined as an undamaged position.

[0167] The third determination module is used to determine the first damage area and the first damage depth according to the damaged position and the undamaged position.

[0168] Specifically, the first damage area is formed according to the portion of all the damaged positions located at the contour of the copper mesh, and then all damaged parts are dug out and the maximum value of the depth change is compared to obtain the first damage depth.

[0169] In order to ensure the accuracy of the numerical model, in an optional implementation, the above-mentioned device further includes:

[0170] The third calculation unit is used to calculate the difference between the first damage area and the second damage area to obtain the first deviation, calculate the difference between the first damage depth and the second damage depth to obtain the second deviation, and then, when the first deviation or the second deviation is greater than the first threshold, increase the preset coefficient with a preset gradient and recalculate the first deviation and the second deviation until both the first deviation and the second deviation are less than or equal to the first threshold.

[0171] Specifically, when the damage characteristic parameter in the numerical model is smaller than the damage characteristic parameter of the actual sample, the preset coefficient is increased, the gradient is set to 1, and the damage characteristic parameter is recalculated each time the preset coefficient changes.

[0172] Furthermore, if the damage characteristic parameter in the numerical model is greater than the damage characteristic parameter of the actual sample, the above preset coefficient is reduced, and the gradient is set to 1. Each time the preset coefficient changes, the above damage characteristic parameter is recalculated.

[0173] The preset coefficients are adjusted repeatedly until the above damage characteristics are consistent, and it is determined that the simulation accuracy of the numerical model for the effect of the arc injection energy of the middle joint channel on the copper mesh meets the requirements.

[0174] The above-mentioned critical value calculation device of arc injection energy of the intermediate joint channel includes a processor and a memory. The above-mentioned first acquisition unit, the second acquisition unit, the first calculation unit and the second calculation unit are all stored in the memory as program units, and the processor executes the above-mentioned program units stored in the memory to realize corresponding functions. The above-mentioned modules are all located in the same processor; or, the above-mentioned modules are located in different processors in any combination.

[0175] The processor includes a kernel, which calls the corresponding program unit from the memory. One or more kernels can be set, and the energy injected into the copper mesh by the channel arc at the moment of the intermediate joint breakdown can be predicted by adjusting the kernel parameters.

[0176] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0177] An embodiment of the present invention provides a computer-readable storage medium, which includes a stored program, wherein when the program is running, the device where the computer-readable storage medium is located is controlled to execute the critical value calculation method of the arc injection energy of the intermediate joint channel.

[0178] Specifically, the critical value calculation method of the arc injection energy of the intermediate joint channel includes:

[0179] Step S201, obtaining a first target parameter, and calculating the injection heat of the copper mesh according to the first target parameter to obtain a first injection heat, wherein the first target parameter at least includes a current density, a current and a radius of a channel arc;

[0180] In the specific implementation, the relevant parameters of the copper mesh are first obtained and a numerical model is constructed, which includes constructing a geometric model in the numerical model according to the collective structure of the copper mesh to ensure that the collective model is consistent with the actual sample. In addition, the material parameters of the actual sample are consistent with the numerical model.

[0181] Specifically, the above numerical model is used to calculate the Joule heat effect and arc heat transfer effect in the heat source received by the copper mesh based on relevant parameters of the channel arc, namely the above first target parameters, to obtain the above first injected heat.

[0182] Step S202, obtaining a second target parameter, calculating the heat conduction process of the copper mesh according to the first injected heat and the second target parameter to obtain a transient temperature distribution of the copper mesh, wherein the second target parameter at least includes a density and a specific heat capacity of the copper mesh;

[0183] Specifically, in order to simulate the damage of the copper mesh caused by the energy injected by the channel arc during the breakdown of the intermediate joint, in addition to considering the heat injected into the copper mesh by the channel current of the intermediate joint, the heat conduction and phase change effect in the copper mesh must also be considered. Specifically, through the above numerical model, based on the material parameters of the copper mesh, that is, the above second target parameters, the temperature distribution of the copper mesh during the heat conduction process in the copper mesh is calculated to obtain the above transient temperature distribution of the copper mesh.

[0184] Step S203, determining the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh, obtaining a first damage area and a first damage depth, obtaining an actual damage area and an actual damage depth of the copper mesh, and obtaining a second damage area and a second damage depth;

[0185] Specifically, the above numerical model is based on the above copper mesh transient distribution, combined with the preset copper mesh phase change temperature threshold, the damage area and damage depth of the copper mesh can be determined, that is, the part whose temperature exceeds the phase change temperature threshold is determined to be damaged, and the above first damage area and the above first damage depth are obtained. Then the damage area and damage depth of the actual sample are measured to obtain the above second damage area and second damage depth.

[0186] Step S204, calculate the difference between the first damage area and the second damage area to obtain a first deviation, calculate the difference between the first damage depth and the second damage depth to obtain a second deviation, and when the first deviation and the second deviation are both less than or equal to the first threshold, calculate the injection energy of the arc of the intermediate joint channel into the copper mesh according to the second target parameter to obtain an energy critical value.

[0187] Specifically, the damage area and damage depth are determined as damage characteristic parameters. Due to the randomness of the intermediate joint breakdown process, the same injection energy may cause different damage to the copper mesh. The present application is set to allow the calculated damage characteristic parameters to be less than the first threshold value (10%) when the deviation between the damage characteristic parameters and the actual sample is less than the above-mentioned first threshold value (10%). At this time, the injection heat of the numerical model is determined, that is, the critical value of the channel arc injection energy is obtained, that is, the above-mentioned energy critical value, and the specific formula is:

[0188] E = ∫∫∫CρΔTdV;

[0189] Among them, E is the above-mentioned energy critical value, C is the specific heat capacity of the copper mesh, ρ is the density of the copper mesh, and ΔT is the transient temperature rise of the numerical model.

[0190] An embodiment of the present invention provides a processor, which is used to run a program, wherein the critical value calculation method of the arc injection energy of the intermediate joint channel is executed when the program is run.

[0191] Specifically, the critical value calculation method of the arc injection energy of the intermediate joint channel includes:

[0192] Step S201, obtaining a first target parameter, and calculating the injection heat of the copper mesh according to the first target parameter to obtain a first injection heat, wherein the first target parameter at least includes a current density, a current and a radius of a channel arc;

[0193] In the specific implementation, the relevant parameters of the copper mesh are first obtained and a numerical model is constructed, which includes constructing a geometric model in the numerical model according to the collective structure of the copper mesh to ensure that the collective model is consistent with the actual sample. In addition, the material parameters of the actual sample are consistent with the numerical model.

[0194] Specifically, the above numerical model is used to calculate the Joule heat effect and arc heat transfer effect in the heat source received by the copper mesh based on relevant parameters of the channel arc, namely the above first target parameters, to obtain the above first injected heat.

[0195] Step S202, obtaining a second target parameter, calculating the heat conduction process of the copper mesh according to the first injected heat and the second target parameter to obtain a transient temperature distribution of the copper mesh, wherein the second target parameter at least includes a density and a specific heat capacity of the copper mesh;

[0196] Specifically, in order to simulate the damage of the copper mesh caused by the energy injected by the channel arc during the breakdown of the intermediate joint, in addition to considering the heat injected into the copper mesh by the channel current of the intermediate joint, the heat conduction and phase change effect in the copper mesh must also be considered. Specifically, through the above numerical model, based on the material parameters of the copper mesh, that is, the above second target parameters, the temperature distribution of the copper mesh during the heat conduction process in the copper mesh is calculated to obtain the above transient temperature distribution of the copper mesh.

[0197] Step S203, determining the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh, obtaining a first damage area and a first damage depth, obtaining an actual damage area and an actual damage depth of the copper mesh, and obtaining a second damage area and a second damage depth;

[0198] Specifically, the above numerical model is based on the above copper mesh transient distribution, combined with the preset copper mesh phase change temperature threshold, the damage area and damage depth of the copper mesh can be determined, that is, the part whose temperature exceeds the phase change temperature threshold is determined to be damaged, and the above first damage area and the above first damage depth are obtained. Then the damage area and damage depth of the actual sample are measured to obtain the above second damage area and second damage depth.

[0199] Step S204, calculate the difference between the first damage area and the second damage area to obtain a first deviation, calculate the difference between the first damage depth and the second damage depth to obtain a second deviation, and when the first deviation and the second deviation are both less than or equal to the first threshold, calculate the injection energy of the arc of the intermediate joint channel into the copper mesh according to the second target parameter to obtain an energy critical value.

[0200] Specifically, the damage area and damage depth are determined as damage characteristic parameters. Due to the randomness of the intermediate joint breakdown process, the same injection energy may cause different damage to the copper mesh. The present application is set to allow the calculated damage characteristic parameters to be less than the first threshold value (10%) when the deviation between the damage characteristic parameters and the actual sample is less than the above-mentioned first threshold value (10%). At this time, the injection heat of the numerical model is determined, that is, the critical value of the channel arc injection energy is obtained, that is, the above-mentioned energy critical value, and the specific formula is:

[0201] E = ∫∫∫CρΔTdV;

[0202] Among them, E is the above-mentioned energy critical value, C is the specific heat capacity of the copper mesh, ρ is the density of the copper mesh, and ΔT is the transient temperature rise of the numerical model.

[0203] An embodiment of the present invention provides a simulation system, the simulation system comprising a processor, a memory, and a program stored in the memory and executable on the processor, and when the processor executes the program, at least the following steps are implemented:

[0204] Step S201, obtaining a first target parameter, and calculating the injection heat of the copper mesh according to the first target parameter to obtain a first injection heat, wherein the first target parameter at least includes a current density, a current and a radius of a channel arc;

[0205] In the specific implementation, the relevant parameters of the copper mesh are first obtained and a numerical model is constructed, which includes constructing a geometric model in the numerical model according to the collective structure of the copper mesh to ensure that the collective model is consistent with the actual sample. In addition, the material parameters of the actual sample are consistent with the numerical model.

[0206] Specifically, the above numerical model is used to calculate the Joule heat effect and arc heat transfer effect in the heat source received by the copper mesh based on relevant parameters of the channel arc, namely the above first target parameters, to obtain the above first injected heat.

[0207] Step S202, obtaining a second target parameter, calculating the heat conduction process of the copper mesh according to the first injected heat and the second target parameter to obtain a transient temperature distribution of the copper mesh, wherein the second target parameter at least includes a density and a specific heat capacity of the copper mesh;

[0208] Specifically, in order to simulate the damage of the copper mesh caused by the energy injected by the channel arc during the breakdown of the intermediate joint, in addition to considering the heat injected into the copper mesh by the channel current of the intermediate joint, the heat conduction and phase change effect in the copper mesh must also be considered. Specifically, through the above numerical model, based on the material parameters of the copper mesh, that is, the above second target parameters, the temperature distribution of the copper mesh during the heat conduction process in the copper mesh is calculated to obtain the above transient temperature distribution of the copper mesh.

[0209] Step S203, determining the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh, obtaining a first damage area and a first damage depth, obtaining an actual damage area and an actual damage depth of the copper mesh, and obtaining a second damage area and a second damage depth;

[0210] Specifically, the above numerical model is based on the above copper mesh transient distribution, combined with the preset copper mesh phase change temperature threshold, the damage area and damage depth of the copper mesh can be determined, that is, the part whose temperature exceeds the phase change temperature threshold is determined to be damaged, and the above first damage area and the above first damage depth are obtained. Then the damage area and damage depth of the actual sample are measured to obtain the above second damage area and second damage depth.

[0211] Step S204, calculate the difference between the first damage area and the second damage area to obtain a first deviation, calculate the difference between the first damage depth and the second damage depth to obtain a second deviation, and when the first deviation and the second deviation are both less than or equal to the first threshold, calculate the injection energy of the arc of the intermediate joint channel into the copper mesh according to the second target parameter to obtain an energy critical value.

[0212] Specifically, the damage area and damage depth are determined as damage characteristic parameters. Due to the randomness of the intermediate joint breakdown process, the same injection energy may cause different damage to the copper mesh. The present application is set to allow the calculated damage characteristic parameters to be less than the first threshold value (10%) when the deviation between the damage characteristic parameters and the actual sample is less than the above-mentioned first threshold value (10%). At this time, the injection heat of the numerical model is determined, that is, the critical value of the channel arc injection energy is obtained, that is, the above-mentioned energy critical value, and the specific formula is:

[0213] E = ∫∫∫CρΔTdV;

[0214] Among them, E is the above-mentioned energy critical value, C is the specific heat capacity of the copper mesh, ρ is the density of the copper mesh, and ΔT is the transient temperature rise of the numerical model.

[0215] The present application also provides a computer program product, which, when executed on a data processing device, is suitable for executing a program for initializing at least the following method steps:

[0216] Step S201, obtaining a first target parameter, and calculating the injection heat of the copper mesh according to the first target parameter to obtain a first injection heat, wherein the first target parameter at least includes a current density, a current and a radius of a channel arc;

[0217] In the specific implementation, the relevant parameters of the copper mesh are first obtained and a numerical model is constructed, which includes constructing a geometric model in the numerical model according to the collective structure of the copper mesh to ensure that the collective model is consistent with the actual sample. In addition, the material parameters of the actual sample are consistent with the numerical model.

[0218] Specifically, the above numerical model is used to calculate the Joule heat effect and arc heat transfer effect in the heat source received by the copper mesh based on relevant parameters of the channel arc, namely the above first target parameters, to obtain the above first injected heat.

[0219] Step S202, obtaining a second target parameter, calculating the heat conduction process of the copper mesh according to the first injected heat and the second target parameter to obtain a transient temperature distribution of the copper mesh, wherein the second target parameter at least includes a density and a specific heat capacity of the copper mesh;

[0220] Specifically, in order to simulate the damage of the copper mesh caused by the energy injected by the channel arc during the breakdown of the intermediate joint, in addition to considering the heat injected into the copper mesh by the channel current of the intermediate joint, the heat conduction and phase change effect in the copper mesh must also be considered. Specifically, through the above numerical model, based on the material parameters of the copper mesh, that is, the above second target parameters, the temperature distribution of the copper mesh during the heat conduction process in the copper mesh is calculated to obtain the above transient temperature distribution of the copper mesh.

[0221] Step S203, determining the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh, obtaining a first damage area and a first damage depth, obtaining an actual damage area and an actual damage depth of the copper mesh, and obtaining a second damage area and a second damage depth;

[0222] Specifically, the above numerical model is based on the above copper mesh transient distribution, combined with the preset copper mesh phase change temperature threshold, the damage area and damage depth of the copper mesh can be determined, that is, the part whose temperature exceeds the phase change temperature threshold is determined to be damaged, and the above first damage area and the above first damage depth are obtained. Then the damage area and damage depth of the actual sample are measured to obtain the above second damage area and second damage depth.

[0223] Step S204, calculate the difference between the first damage area and the second damage area to obtain a first deviation, calculate the difference between the first damage depth and the second damage depth to obtain a second deviation, and when the first deviation and the second deviation are both less than or equal to the first threshold, calculate the injection energy of the arc of the intermediate joint channel into the copper mesh according to the second target parameter to obtain an energy critical value.

[0224] Specifically, the damage area and damage depth are determined as damage characteristic parameters. Due to the randomness of the intermediate joint breakdown process, the same injection energy may cause different damage to the copper mesh. The present application is set to allow the calculated damage characteristic parameters to be less than the first threshold value (10%) when the deviation between the damage characteristic parameters and the actual sample is less than the above-mentioned first threshold value (10%). At this time, the injection heat of the numerical model is determined, that is, the critical value of the channel arc injection energy is obtained, that is, the above-mentioned energy critical value, and the specific formula is:

[0225] E = ∫∫∫CρΔTdV;

[0226] Among them, E is the above-mentioned energy critical value, C is the specific heat capacity of the copper mesh, ρ is the density of the copper mesh, and ΔT is the transient temperature rise of the numerical model.

[0227] Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order than here, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

[0228] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0229] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0230] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0231] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0232] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0233] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0234] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tapes, disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0235] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0236] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0237] 1) The critical value calculation method of the arc injection energy of the intermediate joint channel of the present application, first, obtain a first target parameter, calculate the injection heat of the copper mesh according to the first target parameter to obtain a first injection heat, the first target parameter at least includes the current density, current and radius of the channel arc; then, obtain a second target parameter, calculate the heat conduction process of the copper mesh according to the first injection heat and the second target parameter, and obtain the transient temperature distribution of the copper mesh, the second target parameter at least includes the density and specific heat capacity of the copper mesh; then, determine the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh, obtain a first damage area and a first damage depth, obtain the actual damage area and actual damage depth of the copper mesh, and obtain a second damage area and a second damage depth; finally, calculate the difference between the first damage area and the second damage area to obtain a first deviation, calculate the difference between the first damage depth and the second damage depth to obtain a second deviation, and when the first deviation and the second deviation are both less than or equal to the first threshold, calculate the injection energy of the intermediate joint channel arc to the copper mesh according to the second target parameter to obtain an energy critical value. This application adopts a numerical simulation method, based on a numerical model, to calculate the heat source according to the measured channel arc of the broken-down intermediate joint, and to calculate the estimated damage area and damage depth of the copper mesh in combination with the phase change effect under the high temperature of the copper mesh, and to compare the actual damage area and actual damage depth, and to determine that the channel arc injection energy of the numerical model is the critical value of the channel arc injection energy when the deviation is within the allowable range. This method solves the problem of the lack of a method for calculating the injection energy when the intermediate joint explodes in the prior art.

[0238] 2) The critical value calculation device of the arc injection energy of the intermediate joint channel of the present application, the first acquisition unit acquires the first target parameter, calculates the injection heat of the copper mesh according to the first target parameter to obtain the first injection heat, and the first target parameter at least includes the current density, current and radius of the channel arc; the second acquisition unit acquires the second target parameter, calculates the heat conduction process of the copper mesh according to the first injection heat and the second target parameter, and obtains the transient temperature distribution of the copper mesh, and the second target parameter at least includes the density and specific heat capacity of the copper mesh; the first calculation unit determines the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh, obtains the first damage area and the first damage depth, obtains the actual damage area and the actual damage depth of the copper mesh, and obtains the second damage area and the second damage depth; the second calculation unit calculates the difference between the first damage area and the second damage area to obtain the first deviation, calculates the difference between the first damage depth and the second damage depth to obtain the second deviation, and when the first deviation and the second deviation are both less than or equal to the first threshold, calculates the injection energy of the intermediate joint channel arc to the copper mesh according to the second target parameter to obtain the energy critical value. This application adopts a numerical simulation method, based on a numerical model, to calculate the heat source according to the measured channel arc of the broken-down intermediate joint, and to calculate the estimated damage area and damage depth of the copper mesh in combination with the phase change effect under the high temperature of the copper mesh, and to compare the actual damage area and actual damage depth, and to determine that the channel arc injection energy of the numerical model is the critical value of the channel arc injection energy when the deviation is within the allowable range. This method solves the problem of the lack of a method for calculating the injection energy when the intermediate joint explodes in the prior art.

[0239] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for calculating the critical value of arc injection energy of an intermediate joint channel, characterized in that: The intermediate joint is wrapped with a copper mesh, and the method comprises: Acquire a first target parameter, and calculate the injection heat of the copper mesh according to the first target parameter to obtain a first injection heat, wherein the first target parameter at least includes a current density, a current, and a radius of a channel arc; Acquire a second target parameter, calculate the heat conduction process of the copper mesh according to the first injected heat and the second target parameter, and obtain a transient temperature distribution of the copper mesh, wherein the second target parameter at least includes a density and a specific heat capacity of the copper mesh; Determine the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh, obtain a first damage area and a first damage depth, obtain the actual damage area and actual damage depth of the copper mesh, and obtain a second damage area and a second damage depth; The difference between the first damage area and the second damage area is calculated to obtain a first deviation, and the difference between the first damage depth and the second damage depth is calculated to obtain a second deviation. When the first deviation and the second deviation are both less than or equal to a first threshold, the injection energy of the arc of the intermediate joint channel into the copper mesh is calculated according to the second target parameter to obtain an energy critical value.

2. The method according to claim 1, characterized in that Calculating the injection heat of the copper mesh according to the first target parameter to obtain a first injection heat includes: Acquire a target electric field and a preset volume, calculate the Joule heat injected by the channel arc into the copper mesh according to the target current and the preset volume, and obtain a second injection heat, wherein the target electric field is the electric field inside the copper mesh; Obtain a target current, a preset coefficient and a target radius, and calculate a boundary heat source of the channel arc input into the copper mesh according to the target current, the preset coefficient and the target radius to obtain a third injected heat, wherein the target current is the current of the channel arc, and the target radius is the radius of the channel arc; The second injected heat amount and the third injected heat amount are summed to obtain the first injected heat amount.

3. The method according to claim 2, characterized in that Calculating the Joule heat injected into the copper mesh by the channel arc according to the target current and the preset volume to obtain a second injected heat amount includes: Determine the current density of the copper mesh within the preset volume according to the preset volume to obtain a target current density; Substituting the target current density, the preset volume and the target electric field into the first target formula to calculate the power, the injection power is obtained: P=∫ V lJdV; Wherein, l is the target electric field, V is the preset volume, P is the injection power, and J is the target current density; Substituting the injected power into the second target formula, the second injected heat is obtained: Wherein, W is the second injected heat, and T is the action time of the channel arc.

4. The method according to claim 2, characterized in that: Calculating the boundary heat source of the channel arc input into the copper mesh according to the target current, the preset coefficient and the target radius to obtain a third injected heat, including: Substituting the target current, the preset coefficient and the target radius into the third target formula to calculate the third injected heat: Among them, Q is the third injected heat, a is the preset coefficient, which is used to characterize the influence of the channel arc on the boundary heat source, r is the point r away from the center of the channel arc, I(t) is the target current, R(t) is the target radius, and t is the acquisition time.

5. The method according to claim 1, characterized in that The heat conduction process of the copper mesh is calculated according to the first injected heat and the second target parameter to obtain the transient temperature distribution of the copper mesh, including: Obtaining a target density, a target specific heat capacity, a target heat transfer coefficient and a first target temperature, wherein the target density is the density of the copper mesh, the target specific heat capacity is the specific heat capacity of the copper mesh, the target heat transfer coefficient is the heat transfer coefficient of the copper mesh, the target electrical conductivity is the electrical conductivity of the copper mesh, and the first target temperature is the initial temperature of the copper mesh; A heat conduction equation is constructed according to the target density, the target specific heat capacity, the target heat transfer coefficient, the target conductivity and the first target temperature: Wherein, ρ is the target density, C is the target specific heat capacity, dθ is the temperature change, is a gradient operator, k is the target heat transfer coefficient, θ is the initial temperature, and M satisfies M=Q+W; Obtaining a target mass and a target latent heat, wherein the target mass is the mass of the copper mesh, and the target latent heat is the latent heat of a phase change of the copper mesh; The phase change equation is constructed according to the target mass and the target latent heat: Wherein, m is the target mass, and L is the target latent heat; The heat conduction equation and the phase change equation are simultaneously solved to obtain the transient temperature distribution of the copper mesh.

6. The method according to claim 1, characterized in that Determining the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh to obtain a first damage area and a first damage depth includes: A three-dimensional rectangular coordinate system is constructed with any position of the copper mesh as the origin, and the temperature of each position of the copper mesh in the three-dimensional rectangular coordinate system is traversed to obtain a second target temperature; When the second target temperature is greater than or equal to a second threshold, the corresponding position is determined as a damaged position, and when the second target temperature is less than the second threshold, the corresponding position is determined as an undamaged position; The first damaged area and the first damaged depth are determined according to the damaged position and the undamaged position.

7. The method according to claim 4, characterized in that After calculating the difference between the first damage area and the second damage area to obtain a first deviation, and calculating the difference between the first damage depth and the second damage depth to obtain a second deviation, the method further includes: When the first deviation or the second deviation is greater than the first threshold, the preset coefficient is increased with a preset gradient and the first deviation and the second deviation are recalculated until both the first deviation and the second deviation are less than or equal to the first threshold.

8. A device for calculating the critical value of arc injection energy of an intermediate joint channel, characterized in that: The intermediate joint is wrapped with a copper mesh, and the device comprises: A first acquisition unit, configured to acquire a first target parameter, and calculate the injection heat of the copper mesh according to the first target parameter to obtain a first injection heat, wherein the first target parameter at least includes a current density, a current, and a radius of a channel arc; a second acquisition unit, configured to acquire a second target parameter, and calculate the heat conduction process of the copper mesh according to the first injected heat and the second target parameter to obtain a transient temperature distribution of the copper mesh, wherein the second target parameter at least includes a density and a specific heat capacity of the copper mesh; A first calculation unit is used to determine the damage area and damage depth of the copper mesh according to the transient distribution of the copper mesh, obtain a first damage area and a first damage depth, obtain an actual damage area and an actual damage depth of the copper mesh, and obtain a second damage area and a second damage depth; The second calculation unit is used to calculate the difference between the first damage area and the second damage area to obtain a first deviation, and calculate the difference between the first damage depth and the second damage depth to obtain a second deviation. When the first deviation and the second deviation are both less than or equal to the first difference, the injection energy of the arc of the intermediate joint channel into the copper mesh is calculated according to the second target parameter to obtain an energy critical value.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the method according to any one of claims 1 to 7.

10. A simulation system, characterized in that: include: One or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include methods for executing any one of claims 1 to 7.

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