Methods, apparatus, equipment, and media for determining the contact temperature of high-voltage vacuum interrupters.

Abstract

This invention relates to the field of hot spot temperature monitoring in high-voltage switchgear, and discloses a method, apparatus, equipment, and medium for determining the contact temperature of a high-voltage vacuum interrupter. The method includes: constructing a quantitative calculation model relating the contact temperature of the high-voltage vacuum interrupter to the load current and ambient temperature; establishing an electromagnetic-temperature multiphysics simulation calculation model for the high-voltage vacuum interrupter; obtaining the numerical changes of relevant parameters in the quantitative calculation model under different load currents and different ambient temperatures at a set ambient temperature, based on the simulation calculation model; calculating the relevant parameter values ​​in the quantitative calculation model under different load currents and different ambient temperatures; fitting the correlation equations of the relevant parameters based on these values ​​and combining them with the quantitative calculation model to determine the contact temperature value when current flows through the high-voltage vacuum interrupter. This method of obtaining the actual contact temperature of a high-voltage vacuum interrupter using multiphysics simulation and fitting correlation equations is simple and efficient.

Description

Technical Field

[0001] This invention relates to the field of hot spot temperature monitoring in high-voltage switchgear, and in particular to a method, apparatus, equipment, and medium for determining the contact temperature of a high-voltage vacuum interrupter. Background Technology

[0002] Vacuum interruption boasts technological advantages such as high breaking capacity and outstanding environmental performance, making it one of the most effective means to completely replace sulfur hexafluoride (SF6) gas in high-voltage switchgear. The vacuum interrupter is the core component of vacuum switchgear, and its performance determines the overall performance of the vacuum switch. Only a major breakthrough in interrupter technology can bring about a significant improvement in the level of vacuum interruption technology.

[0003] Vacuum interrupter contacts are sealed in a closed vacuum environment. Traditional temperature detection methods cannot directly measure the temperature of vacuum interrupter contacts, and there is currently a lack of research on calculating the temperature of vacuum interrupter contacts in high-voltage vacuum switchgear. With the continuous increase in the allowable rated current of high-voltage vacuum interrupters, how to obtain the contact temperature of high-voltage vacuum interrupters is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide a method, apparatus, equipment, and medium for determining the contact temperature of a high-pressure vacuum interrupter, which can obtain the actual temperature of the contacts of a high-pressure vacuum interrupter in a simple and efficient manner, ensuring the safe operation of the vacuum interrupter.

[0005] To solve the above-mentioned technical problems, the present invention provides a method for determining the contact temperature of a high-voltage vacuum interrupter, the method comprising:

[0006] A quantitative calculation model is constructed to correlate the contact temperature of the high-voltage vacuum interrupter with the load current and ambient temperature.

[0007] A geometric model of the actual high-pressure vacuum interrupter was simulated, and an electromagnetic-temperature multiphysics simulation calculation model of the high-pressure vacuum interrupter was established.

[0008] Based on the electromagnetic-temperature multiphysics simulation model of the high-voltage vacuum interrupter, the numerical changes of relevant parameters in the quantitative calculation model under different load currents at a set ambient temperature are obtained, as well as the numerical changes of relevant parameters in the quantitative calculation model under different ambient temperatures at a set load current.

[0009] By combining the numerical changes of the relevant parameters obtained with the electromagnetic-temperature multiphysics simulation calculation model of the high-pressure vacuum interrupter, the relevant parameter values ​​in the quantitative calculation model under different load currents and different ambient temperatures are calculated.

[0010] Based on the relevant parameter values ​​in the quantitative calculation model under different load currents and ambient temperatures, the correlation equations and functions of the relevant parameters are fitted, and the contact temperature value when the high-voltage vacuum interrupter is filled is determined by combining the correlation equations and functions with the quantitative calculation model.

[0011] Firstly, in the method for determining the contact temperature of the high-voltage vacuum interrupter provided by the present invention, the expression of the quantitative calculation model is as follows:

[0012] ;

[0013] in, To be in ambient temperature The magnitude of the flow through the arc-extinguishing chamber is At that time, when the flow duration is Contact temperature value at that time; coefficient The absolute value represents the magnitude of temperature change, and the time constant. This indicates the response time for the contact temperature to reach a steady state. This indicates the steady-state temperature of the contact.

[0014] On the other hand, in the above-mentioned method for determining the contact temperature of a high-pressure vacuum interrupter provided by the present invention, the geometric model of the actual high-pressure vacuum interrupter is simulated to establish an electromagnetic-temperature multiphysics simulation calculation model of the high-pressure vacuum interrupter, including:

[0015] A model of the high-voltage vacuum interrupter was created by retaining the main circuit of the internal energized conductor, resulting in a three-dimensional geometric model of the vacuum interrupter.

[0016] The eddy current field and temperature field of the three-dimensional geometric model of the arc-extinguishing chamber were simulated to obtain the electromagnetic-temperature multiphysics simulation calculation model of the high-pressure vacuum arc-extinguishing chamber.

[0017] On the other hand, in the above-mentioned method for determining the contact temperature of a high-voltage vacuum interrupter provided by the present invention, the three-dimensional geometric model of the vacuum interrupter includes a contact system model, which includes a coil, a stainless steel support plate, a moving contact plate, a stationary contact plate, and a cylindrical conductive bridge.

[0018] The cylindrical conductive bridge is used to simulate the contact resistance generated by the current contraction effect between the moving contact piece and the stationary contact piece.

[0019] On the other hand, in the above-mentioned method for determining the contact temperature of a high-voltage vacuum interrupter provided by the present invention, based on the electromagnetic-temperature multiphysics simulation calculation model of the high-voltage vacuum interrupter, the numerical changes of relevant parameters in the quantitative calculation model under different load currents at a set ambient temperature are obtained, including:

[0020] Based on the electromagnetic-temperature multiphysics simulation model of the high-voltage vacuum interrupter, the time-varying curves of the interrupter contact temperature under different load currents at a set ambient temperature were obtained.

[0021] An exponential fitting analysis was performed on the time-varying curves of the arc-extinguishing chamber contact temperature under different load currents at a set ambient temperature to obtain the numerical changes of relevant parameters in the quantitative calculation model under different load currents at the set ambient temperature.

[0022] On the other hand, in the above-mentioned method for determining the contact temperature of a high-voltage vacuum interrupter provided by the present invention, based on the electromagnetic-temperature multiphysics simulation calculation model of the high-voltage vacuum interrupter, the numerical changes of relevant parameters in the quantitative calculation model under different ambient temperatures under a set load current are obtained, including:

[0023] Based on the electromagnetic-temperature multiphysics simulation model of the high-voltage vacuum interrupter, the time-varying curves of the interrupter contact temperature under different ambient temperatures under a set load current were obtained.

[0024] An exponential fitting analysis was performed on the time-varying curves of the arc-extinguishing chamber contact temperature under different ambient temperatures at a set load current to obtain the numerical changes of relevant parameters in the quantitative calculation model under different ambient temperatures at a set load current.

[0025] On the other hand, in the above-mentioned method for determining the contact temperature of a high-voltage vacuum interrupter provided by the present invention, the correlation equation function of the relevant parameters is fitted according to the relevant parameter values ​​in the quantitative calculation model under different load currents and different ambient temperatures, including:

[0026] The relevant parameter values ​​in the quantitative calculation model under different load currents and ambient temperatures are analyzed to generate the relationship between the relevant parameters in the quantitative calculation model and the load current and ambient temperature.

[0027] Based on the relationship between the relevant parameters in the quantitative calculation model and the load current and ambient temperature, the correlation equations and functions of the relevant parameters are fitted.

[0028] To address the aforementioned technical problems, the present invention also provides a device for determining the contact temperature of a high-voltage vacuum interrupter, the device comprising:

[0029] The quantitative calculation model building module is used to build a quantitative calculation model that relates the contact temperature of the high-voltage vacuum interrupter to the load current and ambient temperature.

[0030] The simulation calculation model building module is used to simulate the geometric model of the actual high-pressure vacuum interrupter and to build an electromagnetic-temperature multiphysics simulation calculation model of the high-pressure vacuum interrupter.

[0031] The numerical change acquisition module is used to obtain the numerical changes of relevant parameters in the quantitative calculation model under different load currents at a set ambient temperature, based on the electromagnetic-temperature multiphysics field simulation calculation model of the high-voltage vacuum interrupter.

[0032] The parameter value calculation module is used to combine the numerical changes of the obtained relevant parameters with the electromagnetic-temperature multiphysics simulation calculation model of the high-pressure vacuum interrupter to calculate the relevant parameter values ​​in the quantitative calculation model under different load currents and different ambient temperatures.

[0033] The function fitting module is used to fit the correlation equation function of the relevant parameters in the quantitative calculation model under different load currents and different ambient temperatures.

[0034] The temperature value determination module is used to determine the contact temperature value when the high-pressure vacuum interrupter is filled with current by combining the correlation equation function with the quantitative calculation model.

[0035] To address the aforementioned technical problems, the present invention also provides a device for determining the contact temperature of a high-voltage vacuum interrupter, the device comprising:

[0036] Memory, used to store computer programs;

[0037] A processor is used to execute the computer program to implement the steps of the above-described method for determining the contact temperature of a high-voltage vacuum interrupter.

[0038] To address the aforementioned technical problems, the present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the above-described method for determining the contact temperature of a high-voltage vacuum interrupter.

[0039] As can be seen from the above technical solution, the present invention provides a method for determining the contact temperature of a high-voltage vacuum interrupter. This method includes: constructing a quantitative calculation model relating the contact temperature of the high-voltage vacuum interrupter to the load current and ambient temperature; simulating the geometric model of the actual high-voltage vacuum interrupter to establish an electromagnetic-temperature multi-physics simulation calculation model; obtaining the numerical changes of relevant parameters in the quantitative calculation model under different load currents at a set ambient temperature, and the numerical changes of relevant parameters in the quantitative calculation model under different ambient temperatures at a set load current, based on the electromagnetic-temperature multi-physics simulation calculation model of the high-voltage vacuum interrupter; combining the obtained numerical changes of relevant parameters with the electromagnetic-temperature multi-physics simulation calculation model of the high-voltage vacuum interrupter to calculate the values ​​of relevant parameters in the quantitative calculation model under different ambient temperatures at different load currents; fitting the correlation equations and functions of the relevant parameters based on the values ​​of relevant parameters in the quantitative calculation model under different ambient temperatures at different load currents, and using the correlation equations and functions combined with the quantitative calculation model to determine the contact temperature value when the high-voltage vacuum interrupter is in operation.

[0040] The beneficial effects of this invention are as follows: The method for determining the contact temperature of a high-voltage vacuum interrupter provided by this invention first constructs a quantitative calculation model relating the contact temperature of the high-voltage vacuum interrupter to the load current and ambient temperature, and establishes an electromagnetic-temperature multiphysics simulation calculation model for the high-voltage vacuum interrupter. Then, this simulation calculation model is used to obtain the numerical changes of relevant parameters in the quantitative calculation model under different load currents at a set ambient temperature and under different ambient temperatures at a set load current. Finally, the values ​​of relevant parameters in the quantitative calculation model are calculated under different load currents and different ambient temperatures. Based on these relevant parameter values, the correlation equations of the relevant parameters are fitted. By combining these correlation equations with the quantitative calculation model, the contact temperature values ​​under different load currents, ambient temperatures, and current flow times when the high-voltage vacuum interrupter is flowing can finally be obtained. In this way, by using multiphysics simulation and fitting correlation equations, the temperature of the vacuum interrupter contacts in actual high-voltage switchgear, which is difficult to measure directly, is obtained. This method is simple and efficient, providing technical support for overcoming the problem of sensing the contact temperature of large-scale complex vacuum interrupters, thereby ensuring the safe operation of the vacuum interrupter.

[0041] Furthermore, this invention also provides a corresponding high-voltage vacuum interrupter contact temperature determination device, high-voltage vacuum interrupter contact temperature determination equipment, and computer-readable storage medium for the high-voltage vacuum interrupter contact temperature determination method. These devices have the same or corresponding technical features as the aforementioned high-voltage vacuum interrupter contact temperature determination method, and achieve the same effects. Attached Figure Description

[0042] To more clearly illustrate the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 A flowchart of a method for determining the contact temperature of a high-voltage vacuum interrupter provided in an embodiment of the present invention;

[0044] Figure 2 A flowchart corresponding to the quantitative calculation model of the contact temperature of the high-voltage vacuum interrupter provided in the embodiments of the present invention;

[0045] Figure 3 The flowchart is the corresponding to the electromagnetic-temperature multiphysics simulation calculation model of the high-pressure vacuum interrupter provided in the embodiments of the present invention;

[0046] Figure 4 The flowcharts for verifying the validity of the correlation equations and functional expressions of fitting relevant parameters provided in the embodiments of the present invention are as follows:

[0047] Figure 5 This is a schematic diagram of the time-varying temperature curves of the arc-extinguishing chamber contacts under different load currents, provided in an embodiment of the present invention.

[0048] Figure 6 A schematic diagram of the time-varying curves of the arc-extinguishing chamber contact temperature under different ambient temperatures provided in an embodiment of the present invention;

[0049] Figure 7 A schematic diagram comparing the calculation results of the quantitative calculation model of the contact temperature of the high-pressure vacuum interrupter provided in the embodiment of the present invention with the simulation results of the contact temperature;

[0050] Figure 8 This is a schematic diagram of the high-voltage vacuum interrupter contact temperature determination device provided in an embodiment of the present invention;

[0051] Figure 9 This is a schematic diagram of the high-voltage vacuum interrupter contact temperature determination device provided in an embodiment of the present invention. Detailed Implementation

[0052] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present invention.

[0053] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Figure 1 A flowchart of the method for determining the contact temperature of a high-voltage vacuum interrupter provided in an embodiment of the present invention is shown below. Figure 1 As shown, the method includes:

[0054] S101. Construct a quantitative calculation model that correlates the contact temperature of the high-voltage vacuum interrupter with the load current and ambient temperature.

[0055] It should be noted that the temperature of the arc-extinguishing chamber contacts increases exponentially with the current-carrying time under different load currents and ambient temperatures. In order to quantitatively analyze the influence of load current and ambient temperature on the temperature rise of the arc-extinguishing chamber contacts, this invention constructs a quantitative calculation model relating the arc-extinguishing chamber contact temperature to load current and ambient temperature during step S101.

[0056] S102. Simulate the geometric model of the actual high-pressure vacuum interrupter and establish an electromagnetic-temperature multiphysics simulation calculation model for the high-pressure vacuum interrupter.

[0057] It is understood that the electromagnetic-temperature multiphysics simulation model of the high-pressure vacuum interrupter established in this invention is a calculation model that uses simulation software to simulate and predict the relevant parameter values ​​of the high-pressure vacuum interrupter under the action of eddy current field and temperature field.

[0058] S103. Based on the electromagnetic-temperature multiphysics simulation calculation model of the high-voltage vacuum interrupter, the numerical changes of relevant parameters in the quantitative calculation model under different load currents at a set ambient temperature are obtained.

[0059] S104. Combine the numerical changes of the obtained relevant parameters with the electromagnetic-temperature multiphysics simulation calculation model of the high-voltage vacuum interrupter to calculate the relevant parameter values ​​in the quantitative calculation model under different load currents and ambient temperatures.

[0060] S105. Fit the correlation equations and functions of the relevant parameters in the quantitative calculation model under different load currents and ambient temperatures, and use the correlation equations and functions in combination with the quantitative calculation model to determine the contact temperature value when the high-voltage vacuum interrupter is in operation.

[0061] The method for determining the contact temperature of a high-voltage vacuum interrupter provided in this invention first constructs a quantitative calculation model relating the contact temperature of the high-voltage vacuum interrupter to the load current and ambient temperature. An electromagnetic-temperature multiphysics simulation calculation model for the high-voltage vacuum interrupter is then established. This simulation model is then used to obtain the numerical changes of relevant parameters in the quantitative calculation model under different load currents and different ambient temperatures at a given ambient temperature. Finally, the values ​​of relevant parameters in the quantitative calculation model are calculated under different load currents and different ambient temperatures. Based on these values, correlation equations are fitted to the relevant parameters. By combining these correlation equations with the quantitative calculation model, the contact temperature values ​​under different load currents, ambient temperatures, and current flow times when the high-voltage vacuum interrupter is flowing are finally obtained. This method, using multiphysics simulation and fitting correlation equations, obtains the temperature of vacuum interrupter contacts in actual high-voltage switchgear, which is difficult to measure directly. It is simple and efficient, providing technical support for overcoming the challenge of sensing the contact temperature of large-scale, complex vacuum interrupters, thereby ensuring the safe operation of the vacuum interrupter.

[0062] Furthermore, in specific implementation, in the above-mentioned method for determining the contact temperature of the high-voltage vacuum interrupter provided in the embodiments of the present invention, the expression of the quantitative calculation model relating the contact temperature of the high-voltage vacuum interrupter to the load current and ambient temperature in step S101 can be:

[0063] (1)

[0064] In the formula, To be in ambient temperature The magnitude of the flow through the arc-extinguishing chamber is At that time, when the flow duration is Contact temperature value at that time; coefficient The absolute value reflects the magnitude of temperature change, while the time constant... This reflects the response time for the contact temperature to reach a steady state. This is the steady-state temperature of the contact. This refers to the duration of the flow.

[0065] In implementation, such as Figure 2 As shown, the relevant parameters in the above quantitative calculation model include coefficients. Absolute value, time constant steady-state temperature of the contact point wait. These are the input variables in the quantitative calculation model expression (1); coefficients Time constant steady-state temperature of the contact point It is a functional expression, and its specific functional expression is derived through subsequent data fitting. Among them, When fixed, The variable of contact temperature will change with It changes with the changes; similarly, When fixed, Will follow It changes with the changes.

[0066] Furthermore, in a specific implementation, in the above-mentioned method for determining the contact temperature of a high-voltage vacuum interrupter provided in the embodiments of the present invention, step S102 simulates the geometric model of the actual high-voltage vacuum interrupter and establishes an electromagnetic-temperature multi-physics simulation calculation model of the high-voltage vacuum interrupter. Specifically, this may include: modeling the actual high-voltage vacuum interrupter, retaining the main circuit of the internal current-carrying conductor, and obtaining a three-dimensional geometric model of the vacuum interrupter; simulating the eddy current field and temperature field of the three-dimensional geometric model of the interrupter to obtain an electromagnetic-temperature multi-physics simulation calculation model of the high-voltage vacuum interrupter.

[0067] The three-dimensional geometric model of the vacuum interrupter may include a contact system model, which includes a coil, a stainless steel support plate, a moving contact plate, a stationary contact plate, and a cylindrical conductive bridge. The present invention can use a cylindrical conductive bridge to simulate the contact resistance generated by the current contraction effect between the moving contact plate and the stationary contact plate.

[0068] In implementation, based on the actual high-voltage vacuum interrupter, a 252kV single-break vacuum interrupter was modeled at a 1:1 scale, retaining the internal main conductive circuit. During the simulation modeling of the vacuum interrupter, the contact system of the interrupter was modeled in detail, resulting in higher simulation accuracy. Figure 3 As shown, its structure includes a coil, a stainless steel support plate, contact plates, and a cylindrical conductive bridge with equivalent contact resistance. The detailed modeling of the contact system here refers to meticulously modeling the contacts in the vacuum interrupter according to the actual structure and dimensions of the physical object, minimizing simplification, and accurately reproducing the physical contacts of the vacuum interrupter. This detailed modeling results in more accurate electromagnetic-temperature multiphysics simulation calculations, more realistically reflecting the contact temperature conditions of the interrupter.

[0069] In actual operation, the contact between the moving and stationary contacts is not an ideal, perfectly smooth contact, but rather consists of a finite number of conductive spots. When current flows through these conductive spots, it causes an increase in the current path and resistance; this is called the current contraction effect. The resistance generated by this effect is the contact resistance, and its magnitude is related to the pressure between the contacts. The greater the pressure between the contacts, the better the contact effect and the smaller the contact resistance. Figure 3 As shown, this invention can use a cylindrical conductive bridge to simulate the contact resistance caused by the current contraction effect between the moving and stationary contact pieces, and its radius... The result is obtained from the Holm formula in equation (2):

[0070] (2)

[0071] In the formula, This refers to the contact pressure; the contact pressure of a high-pressure vacuum interrupter is the rated contact pressure. The contact coefficient of the contact surface ranges from 0.3 to 0.6, and is generally taken as 0.45. It can reflect the roughness and elastic-plastic strength of the contact surface. The Brinell hardness is given.

[0072] The mathematical model of the eddy current field in the electromagnetic-temperature multiphysics simulation model of the high-pressure vacuum interrupter is based on Maxwell's equations, and its differential expressions are shown in equations (3) to (9):

[0073] (3)

[0074] (4)

[0075] (5)

[0076] (6)

[0077] (7)

[0078] (8)

[0079] (9)

[0080] In the formula, It is the current density; It is the electric field strength; It is charge density; It is the magnetic field strength; It is the electric flux density; It is magnetic flux density; The conductivity of the medium in the field; The magnetic permeability of the field medium; is the dielectric constant of the field medium.

[0081] When solving for eddy current fields, it is not possible to directly obtain... and Vector magnetic potential is introduced. and scalar potential Vector magnetic potential Satisfying relation (10), scalar potential Satisfy equation (11).

[0082] (10)

[0083] (11)

[0084] Combining equations (3) to (11), the electromagnetic field boundary values ​​in the eddy current and non-eddy current regions of a conductor can be derived as equations (12) and (13):

[0085] (12)

[0086] (13)

[0087] In the formula, This indicates the presence of eddies within the region. This indicates that there are no eddies in the region.

[0088] It should be noted that in the subsequent electromagnetic-temperature multiphysics simulation calculation, the simulation software calculates based on the electromagnetic calculation formulas (12) and (13) of the eddy current field derived from Maxwell's equations. Formulas (12) and (13) are integrated into the simulation software.

[0089] Since the interior of the vacuum interrupter is in a vacuum-sealed state, its heat transfer is mainly through heat conduction. The heat generated by the contacts and the internal conductive rod is transferred to the outside along the conductive rod. A very small portion of the heat is transferred through radiation heat transfer through the inner wall of the interrupter. The heat transfer on the outer surface of the interrupter is through natural convection heat transfer in a limited space. The establishment of the simulation calculation model of the temperature field of the vacuum interrupter mainly considers three heat transfer modes: heat conduction, heat convection, and heat radiation. Heat conduction follows Fourier's law, as shown in equation (14):

[0090] (14)

[0091] In the formula, Heat flux density (W / m) 2 ), The thermal conductivity of the material is (W / m·K). For material temperature, The direction of the outward normal to the cross section.

[0092] Thermal convection follows Newton's law of cooling, as shown in equation (15):

[0093] (15)

[0094] In the formula, The convective heat transfer coefficient is... , The solid surface temperature and the surrounding fluid temperature are respectively.

[0095] Thermal radiation follows the Stefan-Boltmann law, and its empirical correction equation is given by equation (16):

[0096] (16)

[0097] In the formula, For heat flux density, This is the Stefan-Boltmann constant, with a value of 5.67 × 10⁻⁶. -8 w / m 2 ·K 4 , The surface area is the area of ​​radiation. For the object's emissivity, The temperature of the arc-extinguishing chamber contacts. This refers to the temperature of the outer casing inside the arc-extinguishing chamber.

[0098] In the simulation, the temperature rise of the material will affect its resistivity. The formula for calculating the conductivity of the material at different temperatures is shown in equation (17):

[0099] (17)

[0100] In the formula, The cold resistivity of the conductor; The temperature coefficient of resistivity of the material; This represents the temperature rise relative to the initial temperature.

[0101] It should be noted that formulas (14) to (17) are all mathematical model formulas for three types of heat transfer. The simulation software also calculates the temperature field based on these formulas. Here, we are explaining the mathematical model of heat transfer that the simulation software uses to calculate the temperature field.

[0102] Furthermore, in a specific implementation, in the high-voltage vacuum interrupter contact temperature determination method provided in the embodiments of the present invention, step S103, based on the electromagnetic-temperature multiphysics simulation calculation model of the high-voltage vacuum interrupter, obtains the numerical changes of relevant parameters in the quantization calculation model under different load currents at a set ambient temperature. Specifically, this may include: obtaining the time-varying curves of the interrupter contact temperature under different load currents at a set ambient temperature based on the electromagnetic-temperature multiphysics simulation calculation model of the high-voltage vacuum interrupter; performing exponential fitting analysis on the time-varying curves of the interrupter contact temperature under different load currents at a set ambient temperature to obtain the numerical changes of relevant parameters in the quantization calculation model under different load currents at a set ambient temperature.

[0103] In implementation, corresponding parameters are set in the simulation software based on the electromagnetic and thermal properties of the material. These parameters include the electromagnetic and thermal property settings of the simulation model, such as material properties, electrical conductivity, thermal conductivity, and voltage-stabilizing heat capacity. For example, the convective heat transfer coefficient of the confined space on the outer surface of the arc extinguisher is 5 W / (m²). 2The convective heat transfer coefficient of the internal surface of the arc-extinguishing chamber is 1.8 W / (m²). 2 The radiation coefficient of the guide rod and contact system is 0.03, and that of the inner wall is 0.91. Taking a 252kV single-break high-voltage vacuum interrupter as an example, the time-varying curves of the interrupter contact temperature under different load currents were calculated using finite element simulation software based on the above simulation model, as shown below. Figure 4 As shown, the set ambient temperature can be 22℃.

[0104] It should be noted that the time-varying curves of the arc-extinguishing chamber contact temperature under different load currents are obtained based on electromagnetic-temperature multiphysics simulation calculations in the simulation software. The mathematical models used in the electromagnetic-temperature field calculations in the simulation software are the electromagnetic eddy current field calculation formulas and heat transfer calculation formulas mentioned earlier.

[0105] Equation (1) was used to perform exponential fitting analysis on the time-varying curves of the arc-extinguishing chamber contact temperature under different load currents. The numerical changes of relevant parameters in the quantitative calculation model of the arc-extinguishing chamber contact temperature under different load currents were obtained, as shown in Table 1.

[0106] Table 1. Values ​​of relevant parameters in the quantitative calculation model of arc-extinguishing chamber contact temperature under different load currents.

[0107]

[0108] Furthermore, in a specific implementation, in the above-mentioned method for determining the contact temperature of a high-voltage vacuum interrupter provided in the embodiments of the present invention, step S103, based on the electromagnetic-temperature multiphysics simulation calculation model of the high-voltage vacuum interrupter, obtains the numerical changes of relevant parameters in the quantitative calculation model under different ambient temperatures at a set load current. Specifically, this may include: obtaining the time-varying curves of the interrupter contact temperature under different ambient temperatures at a set load current based on the electromagnetic-temperature multiphysics simulation calculation model of the high-voltage vacuum interrupter; performing exponential fitting analysis on the time-varying curves of the interrupter contact temperature under different ambient temperatures at a set load current to obtain the numerical changes of relevant parameters in the quantitative calculation model under different ambient temperatures at a set load current.

[0109] In implementation, taking a 252kV single-break vacuum interrupter as an example, based on the electromagnetic-temperature multiphysics simulation model of a high-voltage vacuum interrupter, the time-varying curves of the interrupter contact temperature under different ambient temperatures at a set load current are obtained, such as... Figure 5 As shown, the load current can be set to 4400A.

[0110] Equation (1) was used to perform exponential fitting analysis on the time-varying curves of the arc-extinguishing chamber contact temperature under different ambient temperatures. The numerical changes of relevant parameters in the quantitative calculation model of the arc-extinguishing chamber contact temperature under different ambient temperatures were obtained, as shown in Table 2.

[0111] Table 2. Values ​​of relevant parameters in the quantitative calculation model of arc-extinguishing chamber contact temperature under different ambient temperatures.

[0112]

[0113] Furthermore, in specific implementation, in the above-mentioned method for determining the contact temperature of the high-voltage vacuum interrupter provided in the embodiment of the present invention, when executing step S104, the numerical changes of the obtained relevant parameters are combined with the electromagnetic-temperature multiphysics simulation calculation model of the high-voltage vacuum interrupter to solve for the relevant parameter values ​​in the quantitative calculation model of the interrupter contact temperature under different load currents and ambient temperatures (taking a 252kV single-break vacuum interrupter as an example), as shown in Table 3.

[0114] Table 3. Values ​​of relevant parameters in the quantitative calculation model of arc-extinguishing chamber contact temperature under different load currents and ambient temperatures (some key temperature points).

[0115]

[0116] Furthermore, in a specific implementation, in the above-mentioned method for determining the contact temperature of a high-voltage vacuum interrupter provided in the embodiments of the present invention, step S105 fits the correlation equation function of the relevant parameters in the quantitative calculation model under different load currents and different ambient temperatures. Specifically, it may include: analyzing the relevant parameter values ​​in the quantitative calculation model under different load currents and different ambient temperatures, generating the relationship between the relevant parameters in the quantitative calculation model and the load current and ambient temperature; and fitting the correlation equation function of the relevant parameters based on the relationship between the relevant parameters in the quantitative calculation model and the load current and ambient temperature.

[0117] During implementation, the relationship between relevant parameters in the quantitative calculation model and load current and ambient temperature was analyzed and obtained: coefficients Absolute value and steady-state temperature of the contact The time constant is affected by both load current and ambient temperature. It is mainly affected by the load current, and the influence of ambient temperature is negligible.

[0118] Based on the data in Table 3, the time constant was obtained through fitting. With load current The functional relationship is shown in equation (18); the coefficients are obtained by fitting. Absolute value and load current and ambient temperature The correlation equation is shown in equation (19), with a goodness of fit of 99.9%; the steady-state temperature of the contact and the load current are obtained by fitting. and ambient temperature The correlation equations are as shown in equation (20) and Figure 6 As shown, the goodness of fit is 99.17%.

[0119] (18)

[0120] (19)

[0121] (20)

[0122] In summary, the equations and functions of all relevant parameters in the quantitative calculation model of the arc-extinguishing chamber contact temperature in equation (1) have been solved, and the real-time contact temperature of the 252kV vacuum arc-extinguishing chamber contact temperature rise time-varying dynamic process can be constructed. With flow time Load current and ambient temperature The system of related equations is shown in equation (21):

[0123] ;(twenty one)

[0124] It should be noted that formula (1) is a general formula for calculating the contact temperature. When it was proposed, the relationship between the time constant and the ambient temperature was considered. However, in the subsequent analysis, it was found that the relationship between the time constant and the ambient temperature for the 252kV vacuum interrupter contact was very weak. Therefore, the time constant in formula (21) of this embodiment does not take the ambient temperature into account. Formula (21) is only applicable to the embodiments listed in this article, but the derivation method and process of this formula are applicable to the derivation of the formula for calculating the contact temperature of vacuum interrupters of various voltage levels.

[0125] To further demonstrate the effectiveness of the quantitative calculation model for the contact temperature of the vacuum interrupter, an ambient temperature of 22.5℃ was set. Simulation results of dynamic temperature rise of the contact under 0.5 times the rated current (2000A) and the rated current (4000A) were compared and analyzed with the results calculated by the quantitative calculation model. The comparison between the calculation results of the quantitative calculation model and the simulation results of dynamic temperature rise of the contact is as follows. Figure 7 As shown, Figure 7 The value above the dashed circle represents the difference between the calculation results of the contact temperature quantification model and the simulation results.

[0126] Figure 7 The results show that the calculated values ​​of the arc-extinguishing chamber contact temperature by the quantitative calculation model are basically consistent with the simulated values ​​of dynamic temperature rise of the contact. The maximum error is 1.8℃ and the minimum error is 0.038℃, which verifies the effectiveness of the quantitative calculation model proposed in this invention that correlates the contact temperature of the high-voltage vacuum arc-extinguishing chamber with the load current and ambient temperature.

[0127] In the above embodiments, the method for determining the contact temperature of a high-voltage vacuum interrupter has been described in detail. This invention also provides embodiments of a high-voltage vacuum interrupter contact temperature determination device and a high-voltage vacuum interrupter contact temperature determination equipment. It should be noted that this invention describes the embodiments of the device from two perspectives: one based on functional modules, and the other based on hardware.

[0128] Figure 8 This is a schematic diagram of the high-voltage vacuum interrupter contact temperature determination device provided in an embodiment of the present invention. This embodiment is based on functional modules, such as… Figure 8 As shown, the device includes:

[0129] The quantitative calculation model construction module 10 is used to construct a quantitative calculation model that relates the contact temperature of the high-voltage vacuum interrupter to the load current and ambient temperature.

[0130] The simulation calculation model establishment module 11 is used to simulate the geometric model of the actual high-pressure vacuum interrupter and establish the electromagnetic-temperature multi-physics simulation calculation model of the high-pressure vacuum interrupter.

[0131] The numerical change acquisition module 12 is used to obtain the numerical changes of relevant parameters in the quantitative calculation model under different load currents at a set ambient temperature, based on the electromagnetic-temperature multiphysics field simulation calculation model of the high-voltage vacuum interrupter.

[0132] The parameter value calculation module 13 is used to combine the numerical changes of the obtained relevant parameters with the electromagnetic-temperature multiphysics simulation calculation model of the high-voltage vacuum interrupter to calculate the relevant parameter values ​​in the quantitative calculation model under different load currents and different ambient temperatures.

[0133] The function fitting module 14 is used to fit the correlation equation function of the relevant parameters in the quantitative calculation model based on the relevant parameter values ​​under different load currents and different ambient temperatures.

[0134] The temperature value determination module 15 is used to determine the contact temperature value when the high-pressure vacuum interrupter is filled with current by combining the correlation equation function with the quantitative calculation model.

[0135] In the high-voltage vacuum interrupter contact temperature determination device provided in the embodiments of the present invention, the contact temperature values ​​under different load currents, ambient temperatures and current flow times during the high-voltage vacuum interrupter can be obtained through the interaction of the above six modules, by means of multiphysics simulation and fitting correlation equations. It is simple and efficient, providing technical support for overcoming the problem of sensing the contact temperature of large-scale complex structure vacuum interrupters, thereby ensuring the safe operation of vacuum interrupters.

[0136] Since the embodiments of the apparatus and the method correspond to each other, please refer to the description of the embodiments in the method section for the apparatus embodiments, which will not be repeated here. Furthermore, it has the same beneficial effects as the high-pressure vacuum interrupter contact temperature determination method mentioned above.

[0137] Figure 9 This is a schematic diagram of the high-voltage vacuum interrupter contact temperature determination device provided in an embodiment of the present invention. This embodiment is based on a hardware perspective, such as... Figure 9 As shown, the high-voltage vacuum interrupter contact temperature determination device includes:

[0138] Memory 20 is used to store computer programs;

[0139] The processor 21 is used to execute a computer program to implement the steps of the method for determining the contact temperature of the high-voltage vacuum interrupter as mentioned in the above embodiments.

[0140] The processor 21 may include one or more processing cores, such as a quad-core processor or an octa-core processor. The processor 21 may be implemented using at least one of the following hardware forms: Digital Signal Processor (DSP), Field-Programmable Gate Array (FPGA), or Programmable Logic Array (PLA). The processor 21 may also include a main processor and a coprocessor. The main processor, also known as the CPU, is used to process data in the wake-up state; the coprocessor is a low-power processor used to process data in the standby state. In some embodiments, the processor 21 may integrate a Graphics Processing Unit (GPU), which is responsible for rendering and drawing the content to be displayed on the screen. In some embodiments, the processor 21 may also include an Artificial Intelligence (AI) processor, which is used to handle computational operations related to machine learning.

[0141] The memory 20 may include one or more computer-readable storage media, which may be non-transitory. The memory 20 may also include high-speed random access memory and non-volatile memory, such as one or more disk storage devices or flash memory devices. In this embodiment, the memory 20 is used to store at least the following computer program 201, which, after being loaded and executed by the processor 21, is capable of implementing the relevant steps of the high-voltage vacuum interrupter contact temperature determination method disclosed in any of the foregoing embodiments. In addition, the resources stored in the memory 20 may also include an operating system 202 and data 203, and the storage method may be temporary or permanent storage. The operating system 202 may include Windows, Unix, Linux, etc. The data 203 may include, but is not limited to, the data involved in the high-voltage vacuum interrupter contact temperature determination method mentioned above.

[0142] In some embodiments, the high-voltage vacuum interrupter contact temperature determination device may further include a display screen 22, an input / output interface 23, a communication interface 24, a power supply 25, and a communication bus 26. Those skilled in the art will understand that... Figure 9 The structure shown does not constitute a limitation on the high-voltage vacuum interrupter contact temperature determination device, and may include more or fewer components than shown. The high-voltage vacuum interrupter contact temperature determination device provided in this embodiment includes a memory and a processor. When the processor executes the program stored in the memory, it can implement the high-voltage vacuum interrupter contact temperature determination method mentioned above, achieving the same effect.

[0143] Finally, the present invention also provides an embodiment corresponding to a computer-readable storage medium. The computer-readable storage medium stores a computer program, which, when executed by a processor, performs the steps described in the above method embodiments.

[0144] It is understood that if the methods in the above embodiments are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and executes all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks. The computer-readable storage medium provided by the present invention can realize the above-mentioned method for determining the contact temperature of the high-voltage vacuum interrupter, with the same effect.

[0145] Finally, the present invention also provides an embodiment corresponding to a computer program product. The computer program product includes a computer program / instructions, which, when executed by a processor, implement the steps described in the above embodiment of the method for determining the contact temperature of a high-voltage vacuum interrupter. The computer program product provided by the present invention can implement the aforementioned method for determining the contact temperature of a high-voltage vacuum interrupter, achieving the same effect.

[0146] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0147] The above provides a detailed description of the method, apparatus, equipment, and medium for determining the contact temperature of a high-voltage vacuum interrupter provided by this invention. The various embodiments in the specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section. It should be noted that those skilled in the art can make several improvements and modifications to this invention without departing from the principles of this invention, and these improvements and modifications also fall within the protection scope of this invention.

Claims

1. A method for determining the contact temperature of a high-pressure vacuum interrupter, characterized in that, The method includes: A quantitative calculation model is constructed to correlate the contact temperature of a high-voltage vacuum interrupter with load current and ambient temperature; the expression of the quantitative calculation model is as follows: ； in, To be in ambient temperature The magnitude of the flow through the arc-extinguishing chamber is At that time, when the flow duration is Contact temperature value at that time; coefficient The absolute value represents the magnitude of temperature change, and the time constant. This indicates the response time for the contact temperature to reach a steady state. This indicates the steady-state temperature of the contact. A model of the high-voltage vacuum interrupter was created by retaining the main circuit of the internal energized conductor, resulting in a three-dimensional geometric model of the vacuum interrupter. The eddy current field and temperature field of the three-dimensional geometric model of the arc-extinguishing chamber are simulated to obtain the electromagnetic-temperature multiphysics simulation calculation model of the high-pressure vacuum arc-extinguishing chamber. Based on the electromagnetic-temperature multiphysics simulation model of the high-voltage vacuum interrupter, the numerical changes of relevant parameters in the quantitative calculation model under different load currents at a set ambient temperature are obtained, as well as the numerical changes of relevant parameters in the quantitative calculation model under different ambient temperatures at a set load current. By combining the numerical changes of the relevant parameters obtained with the electromagnetic-temperature multiphysics simulation calculation model of the high-pressure vacuum interrupter, the relevant parameter values ​​in the quantitative calculation model under different load currents and different ambient temperatures are calculated. Based on the relevant parameter values ​​in the quantitative calculation model under different load currents and ambient temperatures, the correlation equations and functions of the relevant parameters are fitted, and the contact temperature value when the high-voltage vacuum interrupter is filled is determined by combining the correlation equations and functions with the quantitative calculation model.

2. The method for determining the contact temperature of a high-voltage vacuum interrupter according to claim 1, characterized in that, The three-dimensional geometric model of the vacuum interrupter includes a contact system model, which comprises a coil, a stainless steel support plate, a moving contact plate, a stationary contact plate, and a cylindrical conductive bridge. The cylindrical conductive bridge is used to simulate the contact resistance generated by the current contraction effect between the moving contact piece and the stationary contact piece.

3. The method for determining the contact temperature of a high-voltage vacuum interrupter according to claim 1, characterized in that, Based on the electromagnetic-temperature multiphysics simulation model of the high-voltage vacuum interrupter, the numerical changes of relevant parameters in the quantitative calculation model under different load currents at a set ambient temperature are obtained, including: Based on the electromagnetic-temperature multiphysics simulation model of the high-voltage vacuum interrupter, the time-varying curves of the interrupter contact temperature under different load currents at a set ambient temperature were obtained. An exponential fitting analysis was performed on the time-varying curves of the arc-extinguishing chamber contact temperature under different load currents at a set ambient temperature to obtain the numerical changes of relevant parameters in the quantitative calculation model under different load currents at the set ambient temperature.

4. The method for determining the contact temperature of a high-voltage vacuum interrupter according to claim 1, characterized in that, Based on the electromagnetic-temperature multiphysics simulation model of the high-voltage vacuum interrupter, the numerical changes of relevant parameters in the quantitative calculation model under different ambient temperatures at a given load current are obtained, including: Based on the electromagnetic-temperature multiphysics simulation model of the high-voltage vacuum interrupter, the time-varying curves of the interrupter contact temperature under different ambient temperatures under a set load current were obtained. An exponential fitting analysis was performed on the time-varying curves of the arc-extinguishing chamber contact temperature under different ambient temperatures at a set load current to obtain the numerical changes of relevant parameters in the quantitative calculation model under different ambient temperatures at a set load current.

5. The method for determining the contact temperature of a high-voltage vacuum interrupter according to claim 1, characterized in that, Based on the relevant parameter values ​​in the quantitative calculation model under different load currents and ambient temperatures, the correlation equations and functional expressions of the relevant parameters are fitted, including: The relevant parameter values ​​in the quantitative calculation model under different load currents and ambient temperatures are analyzed to generate the relationship between the relevant parameters in the quantitative calculation model and the load current and ambient temperature. Based on the relationship between the relevant parameters in the quantitative calculation model and the load current and ambient temperature, the correlation equations and functions of the relevant parameters are fitted.

6. A device for determining the contact temperature of a high-pressure vacuum interrupter, characterized in that, The device includes: The quantitative calculation model construction module is used to construct a quantitative calculation model relating the contact temperature of the high-voltage vacuum interrupter to the load current and ambient temperature; the expression of the quantitative calculation model is: ； in, To be in ambient temperature The magnitude of the flow through the arc-extinguishing chamber is At that time, when the flow duration is Contact temperature value at that time; coefficient The absolute value represents the magnitude of temperature change, and the time constant. This indicates the response time for the contact temperature to reach a steady state. This indicates the steady-state temperature of the contact. The simulation calculation model building module is used to model the actual high-pressure vacuum interrupter, retain the main circuit of the internal current-carrying conductor, and obtain the three-dimensional geometric model of the vacuum interrupter; the eddy current field and temperature field are simulated on the three-dimensional geometric model of the interrupter to obtain the electromagnetic-temperature multiphysics simulation calculation model of the high-pressure vacuum interrupter. The numerical change acquisition module is used to obtain the numerical changes of relevant parameters in the quantitative calculation model under different load currents at a set ambient temperature, based on the electromagnetic-temperature multiphysics field simulation calculation model of the high-voltage vacuum interrupter. The parameter value calculation module is used to combine the numerical changes of the obtained relevant parameters with the electromagnetic-temperature multiphysics simulation calculation model of the high-pressure vacuum interrupter to calculate the relevant parameter values ​​in the quantitative calculation model under different load currents and different ambient temperatures. The function fitting module is used to fit the correlation equation function of the relevant parameters in the quantitative calculation model under different load currents and different ambient temperatures. The temperature value determination module is used to determine the contact temperature value when the high-pressure vacuum interrupter is filled with current by combining the correlation equation function with the quantitative calculation model.

7. A device for determining the contact temperature of a high-pressure vacuum interrupter, characterized in that, The device includes: Memory, used to store computer programs; A processor, configured to execute the computer program to implement the steps of the method for determining the contact temperature of a high-voltage vacuum interrupter as described in any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the method for determining the contact temperature of a high-voltage vacuum interrupter as described in any one of claims 1 to 5.

Images