Switch cabinet circuit breaker contact temperature measuring and calculating method, system, equipment and medium

Abstract

The invention discloses a switch cabinet circuit breaker contact temperature measuring and calculating method, system and device and a medium, mainly relates to the technical field of contact temperature measuring and calculating, and aims to solve the problem that in the prior art, a temperature sensor is usually arranged on the surface of a pole close to a contact, but is affected by the heat transfer process and the environment temperature, so that the contact temperature cannot be measured. And the surface temperature of the pole cannot accurately reflect the real temperature of the contact. Comprising the following steps: importing a simulation model into electromagnetic simulation software, selecting an eddy current field solver, and configuring material electromagnetic attribute parameters of each component; determining resistance parameter data corresponding to the contact resistance, and obtaining an ohmic loss value generated by each component; selecting a thermal simulation module in the electromagnetic simulation software, configuring thermal attribute parameters of materials corresponding to the parts, setting the environment temperature as a preset initial temperature, setting outer surface convection heat transfer coefficients corresponding to the parts on the basis of the preset initial temperature, and further performing simulation to obtain specific temperature rise values of the parts in the simulation model.

Description

Technical Field

[0001] The present application relates to the technical field of switch cabinet circuit breakers, and in particular to a method, system, device and medium for measuring the contact temperature of a switch cabinet circuit breaker. Background Art

[0002] The demand for electric energy is increasing day by day, and the number of switch cabinets is large. Vacuum circuit breakers are core components, and contacts are often burned due to overtemperature due to poor operating conditions. Once the operating characteristics deviate from the allowable range, it will directly affect the safety and stability of the overall operation of the switch cabinet. Therefore, understanding and mastering its temperature distribution law and monitoring and studying its hot spot temperature are of great engineering practical significance to avoid performance damage of the arc extinguishing chamber caused by thermal failure.

[0003] The moving and static contacts in the vacuum interrupter are one of the key parts of the switch cabinet. However, since the vacuum bubble of the KYN series switch cabinet is wrapped in the sealed pole, and the moving and static contacts are located inside the vacuum bubble, the temperature of the interrupter chamber cannot be directly measured. For the convenience of research, when conducting a temperature rise test, the prior art usually places the temperature sensor on the pole surface close to the contact, and uses this as the actual measured temperature of the contact. However, due to the influence of the heat transfer process and the ambient temperature, the pole surface temperature often cannot accurately reflect the actual temperature of the contact, resulting in a large error in this equivalent method. Since the interrupter contact is another thermal fault prone area in addition to the upper and lower plum blossom contacts of the trolley switch, because it is in an absolutely closed environment and has poor heat dissipation conditions, if a thermal fault occurs, it is very likely to cause the interrupter chamber to explode. Therefore, a method, system, equipment and medium for measuring the contact temperature of a switch cabinet circuit breaker are urgently needed to solve the problem that the existing solution usually places the temperature sensor on the pole surface close to the contact, but due to the influence of the heat transfer process and the ambient temperature, the pole surface temperature often cannot accurately reflect the actual temperature of the contact. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present application provides a method, system, device and medium for measuring the contact temperature of a switch cabinet circuit breaker, so as to solve the problem that the prior art usually places the temperature sensor on the surface of the pole close to the contact, but due to the influence of the heat transfer process and the ambient temperature, the surface temperature of the pole often cannot accurately reflect the actual temperature of the contact.

[0005] In the first aspect, the present application provides a method for measuring the contact temperature of a switch cabinet circuit breaker, the method comprising: obtaining a simulation model of the inside of the switch cabinet corresponding to the sealed pole; wherein the components in the simulation model include at least: dynamic and static conductive rods, dynamic and static cover plates, dynamic and static contacts, dynamic and static contact pieces, contact resistance, shielding cover, porcelain column, and sealed pole; obtaining the material electromagnetic property parameters of each component; importing the simulation model into electromagnetic simulation software, selecting an eddy current field solver, and configuring the material electromagnetic property parameters of each component; wherein the material electromagnetic property parameters include at least: material name, relative dielectric constant, conductivity, relative magnetic permeability, and the contact resistance is consistent with the material electromagnetic property parameters of the dynamic and static contact pieces; based on the preset contact pressure and material electromagnetic property parameters, determining the resistance parameter data corresponding to the contact resistance; wherein the resistance parameter data includes at least: contact resistance The equivalent contact radius, contact resistance value and length of the contact resistance are calculated; the resistance parameter data, preset excitation source and preset boundary conditions are added to the electromagnetic simulation software, and then the simulation model is solved to obtain the ohmic loss value generated by each component; the thermal property parameters of the corresponding materials of each component are obtained; the thermal simulation module in the electromagnetic simulation software is selected, the thermal property parameters of the corresponding materials of each component are configured, and the ohmic loss value is coupled as the volume heat source load to the temperature field corresponding to the thermal simulation module, the ambient temperature is set to the preset initial temperature, and the external convection heat transfer coefficient corresponding to each component is set based on the preset initial temperature, and then the specific temperature rise value of each component in the simulation model is obtained by simulation; wherein the thermal property parameters include at least material density, steady-state heat capacity and thermal conductivity, and the external convection heat transfer coefficient of the sealed pole is greater than the convection heat transfer coefficient of other components.

[0006] Furthermore, based on the preset contact pressure and the electromagnetic property parameters of the material, the resistance parameter data corresponding to the contact resistance is determined, specifically including: based on the material name in the electromagnetic property parameters of the material, determining the Brinell hardness, resistivity, and preset K value corresponding to the material.

[0007] By formula: , calculate the equivalent contact radius of contact resistance ; Wherein, F represents the preset contact pressure, the unit is N; H represents the Brinell hardness of the material, the unit is N / mm2; ξ represents the preset correction parameter.

[0008] By formula: , the contact resistance value R is calculated; wherein, K represents a preset K value, m represents a preset constant, and there is a preset corresponding relationship between the specific value of m and the contact form between the moving and static contact pieces.

[0009] By formula: , calculate the length L of the contact resistance; where S represents the cross-sectional area of ​​the conductor, , ρ represents resistivity.

[0010] Furthermore, the preset excitation source includes at least a current value and a current frequency, and the preset boundary conditions include at least setting the eddy current field solver to force the magnetic field strength H to be continuous; adding the resistance parameter data, the preset excitation source and the preset boundary conditions to the electromagnetic simulation software, and then solving the simulation model to obtain the ohmic loss value generated by each component, specifically including: adding the resistance parameter data to the electromagnetic simulation software; based on the preset excitation source, loading the current of the preset current value in the preset excitation source in the eddy current field as excitation, and setting the current frequency to the preset current frequency in the preset excitation source; based on the preset boundary conditions, at the boundary, the eddy current field solver magnetic field strength H is continuous, so that a continuous magnetic field solution is generated in the simulation model; calculating the skin depth of the current-carrying conductor part, and setting the eddy current area grid according to the principle that at least two layers of grids are required within a penetration depth, and using the field calculator to perform volume integration on the ohmic power loss of each component to obtain the ohmic loss value corresponding to each component.

[0011] Furthermore, the Ohm loss value is coupled as a volume heat source load to the temperature field corresponding to the thermal simulation module, the ambient temperature is set as the preset initial temperature, and the external surface convection heat transfer coefficient corresponding to each component is set based on the preset initial temperature, so as to simulate and obtain the specific temperature rise value of each component in the simulation model, which specifically includes: importing the Ohm loss value as a heat source into the temperature field, setting the ambient temperature as the preset initial temperature, setting the external surface convection heat transfer coefficient corresponding to each component, and dividing the grid by combining tetrahedron free decomposition and scanning. After the grid division is completed, the temperature rise of the overall simulation model is solved.

[0012] In the second aspect, the present application provides a switch cabinet circuit breaker contact temperature measurement system, the system comprising: a model acquisition module, used to obtain a simulation model of the inside of the switch cabinet corresponding to the sealed pole; wherein the components in the simulation model include at least: dynamic and static conductive rods, dynamic and static cover plates, dynamic and static contacts, dynamic and static contact pieces, contact resistance, shielding cover, porcelain column, and sealed pole; an electromagnetic configuration module, used to obtain the material electromagnetic property parameters of each component; the simulation model is imported into the electromagnetic simulation software, the eddy current field solver is selected, and the material electromagnetic property parameters of each component are configured; wherein the material electromagnetic property parameters include at least: material name, relative dielectric constant, conductivity, relative magnetic permeability, and the contact resistance is consistent with the material electromagnetic property parameters of the dynamic and static contact pieces; a parameter determination module, used to determine the resistance parameter data corresponding to the contact resistance based on the preset contact pressure and material electromagnetic property parameters; wherein the resistance The parameter data at least include: the equivalent contact radius of the contact resistance, the contact resistance value and the length of the contact resistance; an ohmic loss determination module, which is used to add the resistance parameter data, the preset excitation source and the preset boundary conditions to the electromagnetic simulation software, and then solve the simulation model to obtain the ohmic loss value generated by each component; a temperature rise value determination module, which is used to select the thermal simulation module in the electromagnetic simulation software, set the thermal property parameters of the corresponding materials of each component, couple the ohmic loss value as the volume heat source load to the temperature field corresponding to the thermal simulation module, set the ambient temperature to the preset initial temperature, and set the external convection heat transfer coefficient corresponding to each component based on the preset initial temperature, and then simulate and obtain the specific temperature rise value of each component in the simulation model; wherein the thermal property parameters at least include material density, voltage-stabilizing heat capacity, and thermal conductivity, and the external convection heat transfer coefficient of the sealed pole is greater than the convection heat transfer coefficient of other components.

[0013] Furthermore, the parameter determination module includes a parameter calculation unit for determining the Brinell hardness, resistivity, and preset K value corresponding to the material based on the material name in the material electromagnetic property parameters.

[0014] By formula: , calculate the equivalent contact radius of contact resistance ; Wherein, F represents the preset contact pressure, the unit is N; H represents the Brinell hardness of the material, the unit is N / mm2; ξ represents the preset correction parameter.

[0015] By formula: , the contact resistance value R is calculated; wherein, K represents a preset K value, m represents a preset constant, and there is a preset corresponding relationship between the specific value of m and the contact form between the moving and static contact pieces.

[0016] By formula: , calculate the length L of the contact resistance; where S represents the cross-sectional area of ​​the conductor, , ρ represents resistivity.

[0017] Furthermore, the preset excitation source includes at least a current value and a current frequency, and the preset boundary conditions include at least setting the eddy current field solver to force the magnetic field strength H to be continuous; the ohmic loss determination module includes an ohmic loss determination unit, which is used to add resistance parameter data to the electromagnetic simulation software; based on the preset excitation source, a current with a preset current value in the preset excitation source is loaded in the eddy current field as excitation, and the current frequency is set to the preset current frequency in the preset excitation source; based on the preset boundary conditions, at the boundary, the eddy current field solver magnetic field strength H is continuous, so that a continuous magnetic field solution is generated in the simulation model; the skin depth of the current-carrying conductor part is calculated, and the eddy current area grid is set according to the principle that at least two layers of grids are required within a penetration depth, and the ohmic loss value corresponding to each component is obtained after volume integration of the ohmic power loss of each component using a field calculator.

[0018] Furthermore, the temperature rise value determination module includes a temperature rise value determination unit, which is used to introduce the ohmic loss value as a heat source into the temperature field, set the ambient temperature to the preset initial temperature, set the surface convection heat transfer coefficient corresponding to each component, and divide the grid by combining tetrahedral free subdivision and scanning. After the grid division is completed, the temperature rise of the overall simulation model is solved.

[0019] In a third aspect, the present application provides a switch cabinet circuit breaker contact temperature measurement device, the device comprising: a processor; and a memory on which executable code is stored, and when the executable code is executed, the processor executes a switch cabinet circuit breaker contact temperature measurement method such as any one of the above items.

[0020] In a fourth aspect, the present application provides a non-volatile computer storage medium having computer instructions stored thereon, which when executed implement a method for measuring the contact temperature of a switch cabinet circuit breaker as described in any one of the above items.

[0021] Those skilled in the art can understand that the present application has at least the following beneficial effects: The present application provides a method, system, device and medium for measuring the contact temperature of a switch cabinet circuit breaker. By obtaining a simulation model of the inside of the corresponding sealed pole of the switch cabinet, the electromagnetic-temperature multi-physics field coupling analysis of the model is performed using electromagnetic simulation software. Among them, when the circuit breaker contacts are closed, they will be subject to the contact pressure caused by the elastic deformation of the spring in its operating mechanism. In actual situations, the contact surface between the moving contact and the static contact is not a smooth plane. Therefore, when the loop current flows through the cross section, it can only flow through a limited electrical contact area. This is bound to have a certain hindering effect on the normal flow of current. In engineering, this phenomenon is usually identified as a contact resistance with a certain resistance value generated at the contact position. Based on this, the present application presets the contact pressure and material electromagnetic property parameters, and then simulates the contact resistance generated by the contact pressure between the moving and static contacts between the two contact pieces.

[0022] In addition, there are three ways of heat transfer: conduction, convection and radiation. According to research, radiation heat transfer has little effect on the overall temperature rise of the switch cabinet, so only conduction and convection heat transfer are simulated. Since the interior of the vacuum arc chamber is in a vacuum-sealed state and there is almost no air circulation, this application only considers the heat dissipation form of heat conduction. Configure the thermal property parameters of the corresponding materials of each component, couple the ohmic loss value as a volume heat source load to the temperature field corresponding to the thermal simulation module, set the ambient temperature to the preset initial temperature, and since the outer surface of the sealed pole is directly exposed to the air, the convective heat transfer coefficient value defined by this surface should be slightly larger than that of other surfaces. By solving the model temperature, the specific temperature rise under specific circumstances can be obtained.

[0023] In summary, this application imports the simulation model into the electromagnetic simulation software through the above method, uses the electromagnetic simulation software to perform electromagnetic-temperature multi-physics field coupling analysis on the model, and fits the specific temperature rise under specific circumstances. This solves the problem that the prior art usually places the temperature sensor on the pole surface close to the contact, but due to the influence of the heat transfer process and the ambient temperature, the pole surface temperature often cannot accurately reflect the actual temperature of the contact. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Some embodiments of the present disclosure are described below with reference to the accompanying drawings, in which: Figure 1 It is a flow chart of a method for measuring the contact temperature of a switch cabinet circuit breaker provided in an embodiment of the present application.

[0025] Figure 2 It is a schematic diagram of the internal structure of a switch cabinet circuit breaker contact temperature measurement system provided in an embodiment of the present application.

[0026] Figure 3 It is a schematic diagram of the internal structure of a switch cabinet circuit breaker contact temperature measuring device provided in an embodiment of the present application.

[0027] Figure 4 It is a schematic diagram of the internal structure of a simulation model of the interior of a switch cabinet corresponding to a sealed pole provided in an embodiment of the present application. DETAILED DESCRIPTION

[0028] It should be understood by those skilled in the art that the embodiments described below are only preferred embodiments of the present disclosure, and do not mean that the present disclosure can only be implemented through the preferred embodiments. The preferred embodiments are only used to explain the technical principles of the present disclosure, and are not used to limit the protection scope of the present disclosure. Based on the preferred embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work should still fall within the protection scope of the present disclosure.

[0029] 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.

[0030] The technical solution proposed in the embodiments of the present application is described in detail below with reference to the accompanying drawings.

[0031] The present application embodiment provides a method for measuring the contact temperature of a switch cabinet circuit breaker, such as Figure 1 As shown, the method provided in the embodiment of the present application mainly includes the following steps: Step 110: Obtain a simulation model of the interior of the corresponding sealed pole of the switch cabinet.

[0032] It should be noted that the simulation model Figure 4 As shown, the components in the simulation model at least include: dynamic and static conductive rods, dynamic and static cover plates, dynamic and static contacts, dynamic and static contact sheets, contact resistors, shielding covers, porcelain columns, and sealed poles.

[0033] In addition, the switch cabinet can be a KYN28A-12 / T3150-40 switch cabinet, and the process of obtaining the simulation model of the internal sealed pole corresponding to the switch cabinet can be: using ANSYS simulation software to establish a simulation model of the HYD-12 / 3150-40 sealed pole that matches it. Since the circuit breaker poles are installed independently in phases in the cabinet and maintain a certain spatial distance, the temperature rise effect between the three phases can be ignored. Therefore, this application only takes one phase as the research object, and simplifies it according to the principle of not affecting the temperature rise effect in the pole, retaining the vacuum arc chamber and the main circuit part of the energized conductor inside it, and its structure is from top to bottom static conductive rod, static contact, contact piece, moving contact, and moving conductive rod.

[0034] Step 120, obtaining the electromagnetic property parameters of the materials of each component; importing the simulation model into the electromagnetic simulation software, selecting the eddy current field solver, and configuring the electromagnetic property parameters of the materials of each component.

[0035] It should be noted that the electromagnetic property parameters of the material include at least: material name, relative dielectric constant, conductivity, relative magnetic permeability, and the contact resistance is consistent with the electromagnetic property parameters of the material of the moving and static contact pieces. The electromagnetic simulation software may be Maxwell 3D software.

[0036] As an example, the electromagnetic property parameters of the material may be specifically shown in Table 1 below: Table 1 Material electromagnetic property parameters

[0037] It should be noted that importing the simulation model into the electromagnetic simulation software and selecting the eddy current field solver can be achieved by the prior art, and this application does not limit this. In addition, the material electromagnetic property parameters obtained by this application are the existing material parameter properties. In addition, the configuration process is the parameter configuration process of the existing electromagnetic simulation software, and this application does not limit this.

[0038] Step 130: Determine resistance parameter data corresponding to the contact resistance based on the preset contact pressure and material electromagnetic property parameters.

[0039] It should be noted that in order to further improve the fitting accuracy of the simulation software, the present application proposes a solution for determining the resistance parameter data corresponding to the contact resistance based on the preset contact pressure and material electromagnetic property parameters. The resistance parameter data at least includes: the contact resistance equivalent contact radius, the contact resistance value and the length of the contact resistance.

[0040] The scheme for determining the resistance parameter data corresponding to the contact resistance in this step can be specifically as follows: Based on the material name in the material electromagnetic property parameters, determine the Brinell hardness, resistivity, and preset K value corresponding to the material.

[0041] By formula: , calculate the equivalent contact radius of contact resistance ; Wherein, F represents the preset contact pressure, the unit is N; H represents the Brinell hardness of the material, the unit is N / mm2; ξ represents the preset correction parameter.

[0042] By formula: , calculate and obtain the contact resistance value R; wherein K represents the preset K value, m represents the preset constant, and there is a preset corresponding relationship between the specific value of m and the contact form between the moving and static contact pieces. It is additionally noted that the preset corresponding relationship can be: when the m value and the contact form between the two contact planes are surface contact, the value is 1; when it is not surface contact, any decimal in (0, 1) is randomly selected.

[0043] By formula: , calculate the length L of the contact resistance; where S represents the cross-sectional area of ​​the conductor, , ρ represents resistivity.

[0044] In addition, the present application realizes the resistance parameter data corresponding to the contact resistance through the above step 130, and can further calculate the ohmic loss value generated by each component.

[0045] Step 140: adding the resistance parameter data, the preset excitation source and the preset boundary conditions to the electromagnetic simulation software, and then solving the simulation model to obtain the ohmic loss value generated by each component.

[0046] It should be noted that the preset excitation source at least includes a current value and a current frequency, and the preset boundary condition at least includes setting the eddy current field solver to force the magnetic field strength H to be continuous.

[0047] This step can be specifically as follows: The resistance parameter data is added to the electromagnetic simulation software; based on the preset excitation source, the current of the preset current value in the preset excitation source is loaded in the eddy current field as excitation, and the current frequency is set to the preset current frequency in the preset excitation source; based on the preset boundary conditions, at the boundary, the magnetic field intensity H of the eddy current field solver is continuous, so that a continuous magnetic field solution is generated in the simulation model; the skin depth of the energized conductor part is calculated, and the eddy current area grid is set according to the principle that at least two layers of grids are required within a penetration depth, and the ohmic loss value corresponding to each component is obtained by volume integration of the ohmic power loss of each component using a field calculator.

[0048] It should be noted that the calculation of the skin depth of the current-carrying conductor portion can be implemented by components in the existing technology or electromagnetic simulation software, and this application does not limit the specific calculation process.

[0049] In addition, it can be understood by those skilled in the art that the present application adds resistance parameter data, preset excitation source and preset boundary conditions to the electromagnetic simulation software, and then utilizes the electromagnetic simulation software's own ability to calculate the ohmic loss value generated by each component in the simulation model to achieve the ohmic loss value generated by each component. The present application achieves accurate acquisition of the ohmic loss value generated by each component through the above step 140, which is conducive to the subsequent accurate fitting simulation to obtain the specific temperature rise value of each component in the simulation model.

[0050] Step 150, obtain the thermal property parameters of the materials corresponding to each component; select the thermal simulation module in the electromagnetic simulation software, configure the thermal property parameters of the materials corresponding to each component, couple the ohmic loss value as the volume heat source load to the temperature field corresponding to the thermal simulation module, set the ambient temperature to the preset initial temperature, set the external surface convection heat transfer coefficient corresponding to each component based on the preset initial temperature, and then simulate to obtain the specific temperature rise value of each component in the simulation model.

[0051] It should be noted that the thermal simulation module in the electromagnetic simulation software, Maxwell 3D software itself has the function of performing specific temperature rise values ​​of each component according to thermal property parameters and volume heat source load. This application does not limit the specific implementation process of the thermal simulation module in the electromagnetic simulation software.

[0052] The thermal property parameters include at least material density, steady-state heat capacity, and thermal conductivity, and the convection heat transfer coefficient of the outer surface of the solid-sealed pole is greater than the convection heat transfer coefficient of other components. There is a corresponding relationship between the preset initial temperature and the outer surface convection heat transfer coefficient corresponding to each component, and those skilled in the art can determine the specific corresponding relationship based on multiple experiments. For example, the ambient temperature is set to 18°C, and the convection heat transfer coefficient of the outer surface of the solid-sealed pole set based on the initial temperature is 6.3 W / (m2∙K), and then the coefficient of the remaining surfaces except the internal surfaces of the vacuum interrupter is set to 2 W / (m2∙K).

[0053] In addition, those skilled in the art can understand that, since the interior of the vacuum arc chamber is in a vacuum-sealed state and there is almost no air circulation, this application only considers the heat dissipation form of heat conduction. Configure the thermal property parameters of the corresponding materials of each component, couple the ohmic loss value as the volume heat source load to the temperature field corresponding to the thermal simulation module, set the ambient temperature to the preset initial temperature, and since the outer surface of the sealed pole is directly exposed to the air, the convective heat transfer coefficient value defined by this surface should be slightly larger than that of other surfaces. By solving the model temperature, the specific temperature rise under specific circumstances can be obtained.

[0054] As an example, the thermal property parameters may be specifically shown in Table 2 below: Table 2 Material thermal property parameters

[0055] In the step, the ohmic loss value is coupled as a volume heat source load to the temperature field corresponding to the thermal simulation module, the ambient temperature is set to the preset initial temperature, and the surface convection heat transfer coefficient corresponding to each component is set based on the preset initial temperature, and then the specific temperature rise value of each component in the simulation model is obtained by simulation, which can be specifically: The Ohm loss value is imported into the temperature field as a heat source, the ambient temperature is set as the preset initial temperature, the surface convection heat transfer coefficient corresponding to each component is set, and the mesh is divided by combining tetrahedron free partitioning and scanning. After the mesh is divided, the temperature rise of the overall simulation model is solved.

[0056] It should be supplemented that the scheme of dividing the grid by combining tetrahedron free decomposition with sweeping is an existing scheme and is not limited in this application.

[0057] Based on the above description, it can be understood by those skilled in the art that the existing switch cabinet circuit breaker contact temperature measurement scheme is mainly: the temperature sensor is placed on the pole surface close to the contact for direct measurement, but due to the influence of the heat transfer process and the ambient temperature, the pole surface temperature often cannot accurately reflect the actual temperature of the contact. In order to solve the problem of not being able to reflect the actual temperature, the present application realizes the precise fitting of specific components by importing the simulation model into the electromagnetic simulation software and setting the material electromagnetic property parameters of each component. In order to further improve the fitting accuracy, the resistance parameter data corresponding to the contact resistance is calculated by presetting the contact pressure and the material electromagnetic property parameters. By adding the resistance parameter data, the preset excitation source and the preset boundary conditions to the electromagnetic simulation software, the ohmic loss value generated by each component in the simulation model is obtained by using the electromagnetic simulation software's own ability to calculate the ohmic loss value generated by each component. Then, the model is subjected to electromagnetic-temperature multi-physics field coupling analysis by using the temperature rise simulation function of the thermal simulation module in the electromagnetic simulation software, and the specific temperature rise under specific circumstances is fitted.

[0058] besides, Figure 2 A switch cabinet circuit breaker contact temperature measurement system is provided in an embodiment of the present application. Figure 2 As shown, the system provided in the embodiment of the present application mainly includes: The model acquisition module 210 is used to acquire the simulation model of the inside of the switch cabinet corresponding to the sealed pole; wherein the components in the simulation model at least include: dynamic and static conductive rods, dynamic and static cover plates, dynamic and static contacts, dynamic and static contact sheets, contact resistors, shielding covers, porcelain columns, and sealed poles; The electromagnetic configuration module 220 is used to obtain the electromagnetic property parameters of the materials of each component; import the simulation model into the electromagnetic simulation software, select the eddy current field solver, and configure the electromagnetic property parameters of the materials of each component; wherein the electromagnetic property parameters of the materials include at least: material name, relative dielectric constant, conductivity, relative magnetic permeability, and the contact resistance is consistent with the electromagnetic property parameters of the materials of the moving and static contact pieces; The parameter determination module 230 is used to determine the resistance parameter data corresponding to the contact resistance based on the preset contact pressure and the material electromagnetic property parameters; wherein the resistance parameter data at least includes: the contact resistance equivalent contact radius, the contact resistance value and the contact resistance length; The parameter determination module 230 includes a parameter calculation unit for determining the Brinell hardness, resistivity, and preset K value corresponding to the material based on the material name in the material electromagnetic property parameters.

[0059] By formula: , calculate the equivalent contact radius of contact resistance ; Wherein, F represents the preset contact pressure, the unit is N; H represents the Brinell hardness of the material, the unit is N / mm2; ξ represents the preset correction parameter.

[0060] By formula: , the contact resistance value R is calculated; wherein, K represents a preset K value, m represents a preset constant, and there is a preset corresponding relationship between the specific value of m and the contact form between the moving and static contact pieces; it is additionally noted that the preset corresponding relationship may be: when the m value and the contact form between the two contact planes are surface contact, the value is 1; when it is not surface contact, any decimal in (0, 1) is randomly selected.

[0061] By formula: , calculate the length L of the contact resistance; where S represents the cross-sectional area of ​​the conductor, , ρ represents resistivity.

[0062] The ohmic loss determination module 240 is used to add the resistance parameter data, the preset excitation source and the preset boundary conditions to the electromagnetic simulation software, and then solve the simulation model to obtain the ohmic loss value generated by each component; It should be noted that the preset excitation source at least includes a current value and a current frequency, and the preset boundary condition at least includes setting the eddy current field solver to force the magnetic field strength H to be continuous.

[0063] The ohmic loss determination module 240 includes an ohmic loss determination unit, which is used to add resistance parameter data to the electromagnetic simulation software; based on a preset excitation source, load a current with a preset current value in the preset excitation source in the eddy current field as excitation, and set the current frequency to the preset current frequency in the preset excitation source; based on preset boundary conditions, at the boundary, the magnetic field intensity H of the eddy current field solver is continuous, so that a continuous magnetic field solution is generated in the simulation model; calculate the skin depth of the current-carrying conductor part, and set the eddy current area grid according to the principle that at least two layers of grids are required within a penetration depth, and use the field calculator to perform volume integration on the ohmic power loss of each component to obtain the ohmic loss value corresponding to each component.

[0064] The temperature rise value determination module 250 is used to select the thermal simulation module in the electromagnetic simulation software, set the thermal property parameters of the materials corresponding to each component, couple the ohmic loss value as the volume heat source load to the temperature field corresponding to the thermal simulation module, set the ambient temperature to the preset initial temperature, and set the external convection heat transfer coefficient corresponding to each component based on the preset initial temperature, and then simulate to obtain the specific temperature rise value of each component in the simulation model; wherein the thermal property parameters include at least material density, voltage-stabilizing heat capacity, and thermal conductivity, and the external convection heat transfer coefficient of the sealed pole is greater than the convection heat transfer coefficient of other components.

[0065] The temperature rise value determination module 250 includes a temperature rise value determination unit, which is used to introduce the ohmic loss value as a heat source into the temperature field, set the ambient temperature to the preset initial temperature, set the surface convection heat transfer coefficient corresponding to each component, and divide the grid by combining tetrahedral free subdivision and scanning. After the grid division is completed, the temperature rise of the overall simulation model is solved.

[0066] The above is a method embodiment of the present application. Based on the same inventive concept, the present application embodiment also provides a switch cabinet circuit breaker contact temperature measurement device. Figure 3 As shown, the device includes: a processor; and a memory, on which executable codes are stored. When the executable codes are executed, the processor executes a method for measuring the contact temperature of a switch cabinet circuit breaker as described in the above embodiment.

[0067] Specifically, the server side obtains a simulation model of the inside of the switch cabinet corresponding to the sealed pole; wherein, the components in the simulation model include at least: dynamic and static conductive rods, dynamic and static cover plates, dynamic and static contacts, dynamic and static contact pieces, contact resistors, shielding covers, porcelain columns, and sealed poles; obtains the material electromagnetic property parameters of each component; imports the simulation model into the electromagnetic simulation software, selects the eddy current field solver, and configures the material electromagnetic property parameters of each component; wherein, the material electromagnetic property parameters include at least: material name, relative dielectric constant, conductivity, relative magnetic permeability, and the contact resistance is consistent with the material electromagnetic property parameters of the dynamic and static contact pieces; based on the preset contact pressure and the material electromagnetic property parameters, determines the resistance parameter data corresponding to the contact resistance; wherein, the resistance parameter data includes at least: contact resistance equivalent contact radius, contact resistance value and the length of the contact resistance; add the resistance parameter data, the preset excitation source and the preset boundary conditions to the electromagnetic simulation software, and then solve the simulation model to obtain the ohmic loss value generated by each component; obtain the thermal property parameters of the corresponding materials of each component; select the thermal simulation module in the electromagnetic simulation software, configure the thermal property parameters of the corresponding materials of each component, couple the ohmic loss value as the volume heat source load to the temperature field corresponding to the thermal simulation module, set the ambient temperature to the preset initial temperature, and set the external convection heat transfer coefficient corresponding to each component based on the preset initial temperature, and then simulate to obtain the specific temperature rise value of each component in the simulation model; wherein the thermal property parameters include at least material density, steady-state heat capacity, and thermal conductivity, and the external convection heat transfer coefficient of the sealed pole is greater than the convection heat transfer coefficient of other components.

[0068] In addition, an embodiment of the present application further provides a non-volatile computer storage medium on which executable instructions are stored. When the executable instructions are executed, a method for measuring the contact temperature of a switch cabinet circuit breaker as described above is implemented.

[0069] So far, the technical solutions of the present disclosure have been described in combination with the above multiple embodiments, but it is easy for those skilled in the art to understand that the protection scope of the present disclosure is not limited to these specific embodiments. Without departing from the technical principles of the present disclosure, those skilled in the art can split and combine the technical solutions in the above-mentioned various embodiments, and can also make equivalent changes or replacements to the relevant technical features. Any changes, equivalent replacements, improvements, etc. made within the technical concept and / or technical principle of the present disclosure will fall within the protection scope of the present disclosure.

Claims

1. A method for measuring the contact temperature of a switch cabinet circuit breaker, characterized in that: The method comprises: Obtain a simulation model of the interior of the corresponding sealed pole of the switch cabinet; wherein the components in the simulation model at least include: dynamic and static conductive rods, dynamic and static cover plates, dynamic and static contacts, dynamic and static contact sheets, contact resistors, shielding covers, porcelain columns, and sealed poles; Obtain the material electromagnetic property parameters of each component; import the simulation model into the electromagnetic simulation software, select the eddy current field solver, and configure the material electromagnetic property parameters of each component; wherein the material electromagnetic property parameters at least include: material name, relative dielectric constant, conductivity, relative magnetic permeability, and the contact resistance is consistent with the material electromagnetic property parameters of the moving and static contact pieces; Based on the preset contact pressure and the electromagnetic property parameters of the material, the resistance parameter data corresponding to the contact resistance is determined; wherein the resistance parameter data at least includes: the contact resistance equivalent contact radius, the contact resistance value and the length of the contact resistance; Add the resistance parameter data, preset excitation source and preset boundary conditions to the electromagnetic simulation software, and then solve the simulation model to obtain the ohmic loss value generated by each component; Obtain thermal property parameters of materials corresponding to each component; select a thermal simulation module in the electromagnetic simulation software, configure thermal property parameters of materials corresponding to each component, couple the ohmic loss value as a volume heat source load to the temperature field corresponding to the thermal simulation module, set the ambient temperature to a preset initial temperature, and set the external convection heat transfer coefficient corresponding to each component based on the preset initial temperature, and then simulate to obtain the specific temperature rise value of each component in the simulation model; wherein the thermal property parameters include at least material density, steady-state heat capacity, and thermal conductivity, and the external convection heat transfer coefficient of the sealed pole is greater than the convection heat transfer coefficient of other components.

2. The method for measuring the contact temperature of a switch cabinet circuit breaker according to claim 1, characterized in that: Based on the preset contact pressure and material electromagnetic property parameters, the resistance parameter data corresponding to the contact resistance is determined, including: Based on the material name in the material electromagnetic property parameters, determine the Brinell hardness, resistivity, and preset K value corresponding to the material; By formula: , calculate the equivalent contact radius of contact resistance ; Wherein, F represents the preset contact pressure, in N; H represents the Brinell hardness of the material, in N / mm2; ξ represents the preset correction parameter; By formula: , calculate and obtain the contact resistance value R; Wherein, K represents a preset K value, m represents a preset constant, and there is a preset corresponding relationship between the specific value of m and the contact form between the moving and static contact pieces; By formula: , calculate the length L of the contact resistance; Where S represents the cross-sectional area of ​​the conductor, , ρ represents resistivity.

3. The method for measuring the contact temperature of a switch cabinet circuit breaker according to claim 1, characterized in that: The preset excitation source includes at least a current value and a current frequency, and the preset boundary condition includes at least setting the eddy current field solver to force the magnetic field strength H to be continuous; The resistor parameter data, preset excitation source and preset boundary conditions are added to the electromagnetic simulation software, and then the simulation model is solved to obtain the ohmic loss value generated by each component, including: Add resistance parameter data to electromagnetic simulation software; Based on a preset excitation source, a current having a preset current value in the preset excitation source is loaded in the eddy current field as excitation, and a current frequency is set to a preset current frequency in the preset excitation source; Based on the preset boundary conditions, at the boundary, the magnetic field intensity H of the eddy current field solver is continuous, so that a continuous magnetic field solution is generated in the simulation model; the skin depth of the current-carrying conductor part is calculated, and the eddy current area grid is set according to the principle that at least two layers of grids are required within a penetration depth. The ohmic power loss of each component is volume integrated using the field calculator to obtain the corresponding ohmic loss value of each component.

4. The method for measuring the contact temperature of a switch cabinet circuit breaker according to claim 1, characterized in that: The ohmic loss value is coupled as a volume heat source load to the temperature field corresponding to the thermal simulation module, the ambient temperature is set as the preset initial temperature, and the surface convection heat transfer coefficient corresponding to each component is set based on the preset initial temperature, and then the specific temperature rise value of each component in the simulation model is obtained by simulation, including: The Ohm loss value is imported into the temperature field as a heat source, the ambient temperature is set as the preset initial temperature, the surface convection heat transfer coefficient corresponding to each component is set, and the mesh is divided by combining tetrahedron free partitioning and scanning. After the mesh is divided, the temperature rise of the overall simulation model is solved.

5. A switch cabinet circuit breaker contact temperature measurement system, characterized in that: The system comprises: The model acquisition module is used to obtain the simulation model of the inside of the corresponding sealed pole of the switch cabinet; wherein the components in the simulation model at least include: dynamic and static conductive rods, dynamic and static cover plates, dynamic and static contacts, dynamic and static contact sheets, contact resistors, shielding covers, porcelain columns, and sealed poles; The electromagnetic configuration module is used to obtain the electromagnetic property parameters of the materials of each component; the simulation model is imported into the electromagnetic simulation software, the eddy current field solver is selected, and the electromagnetic property parameters of the materials of each component are configured; wherein the electromagnetic property parameters of the materials include at least: material name, relative dielectric constant, conductivity, relative magnetic permeability, and the contact resistance is consistent with the electromagnetic property parameters of the materials of the moving and static contact pieces; A parameter determination module, used to determine resistance parameter data corresponding to the contact resistance based on a preset contact pressure and material electromagnetic property parameters; wherein the resistance parameter data at least includes: a contact resistance equivalent contact radius, a contact resistance value, and a contact resistance length; The ohmic loss determination module is used to add the resistance parameter data, the preset excitation source and the preset boundary conditions to the electromagnetic simulation software, and then solve the simulation model to obtain the ohmic loss value generated by each component; A temperature rise value determination module is used to select a thermal simulation module in an electromagnetic simulation software, set thermal property parameters of materials corresponding to each component, couple the ohmic loss value as a volume heat source load to the temperature field corresponding to the thermal simulation module, set the ambient temperature to a preset initial temperature, and set the external convection heat transfer coefficient corresponding to each component based on the preset initial temperature, thereby simulating and obtaining the specific temperature rise value of each component in the simulation model; wherein the thermal property parameters include at least material density, voltage-stabilizing heat capacity, and thermal conductivity, and the external convection heat transfer coefficient of the sealed pole is greater than the convection heat transfer coefficient of other components.

6. The switch cabinet circuit breaker contact temperature measurement system according to claim 5, characterized in that: The parameter determination module includes a parameter calculation unit, Used to determine the Brinell hardness, resistivity, and preset K value corresponding to the material based on the material name in the material electromagnetic property parameters; By formula: , calculate the equivalent contact radius of contact resistance ; Wherein, F represents the preset contact pressure, in N; H represents the Brinell hardness of the material, in N / mm2; ξ represents the preset correction parameter; By formula: , calculate and obtain the contact resistance value R; Wherein, K represents a preset K value, m represents a preset constant, and there is a preset corresponding relationship between the specific value of m and the contact form between the moving and static contact pieces; By formula: , calculate the length L of the contact resistance; Where S represents the cross-sectional area of ​​the conductor, , ρ represents resistivity.

7. The switch cabinet circuit breaker contact temperature measurement system according to claim 5, characterized in that: The preset excitation source includes at least a current value and a current frequency, and the preset boundary condition includes at least setting the eddy current field solver to force the magnetic field strength H to be continuous; The ohmic loss determination module includes an ohmic loss determination unit, Used to add resistance parameter data to electromagnetic simulation software; Based on a preset excitation source, a current having a preset current value in the preset excitation source is loaded in the eddy current field as excitation, and a current frequency is set to a preset current frequency in the preset excitation source; Based on the preset boundary conditions, at the boundary, the magnetic field strength H of the eddy current field solver is continuous, so that a continuous magnetic field solution is generated in the simulation model; The skin depth of the conductor part is calculated, and the eddy current area grid is set according to the principle that at least two layers of grid are required within a penetration depth. The ohmic power loss of each component is volume integrated using the field calculator to obtain the corresponding ohmic loss value of each component.

8. The switch cabinet circuit breaker contact temperature measurement system according to claim 5, characterized in that: The temperature rise value determination module includes a temperature rise value determination unit, It is used to import the ohmic loss value as a heat source into the temperature field, set the ambient temperature as the preset initial temperature, set the surface convection heat transfer coefficient corresponding to each component, and divide the grid by combining tetrahedron free partitioning and scanning. After completing the grid division, the temperature rise of the overall simulation model is solved.

9. A switch cabinet circuit breaker contact temperature measuring device, characterized in that: The device comprises: processor; and a memory storing executable codes thereon, wherein when the executable codes are executed, the processor executes a method for measuring the contact temperature of a circuit breaker of a switch cabinet as claimed in any one of claims 1 to 4.

10. A non-volatile computer storage medium, characterized in that: Computer instructions are stored thereon, and when the computer instructions are executed, a method for measuring the contact temperature of a circuit breaker of a switch cabinet is implemented as described in any one of claims 1 to 4.

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