Method and apparatus for calculating electric arc radiation energy of electric power switch device, and device

Abstract

A method and apparatus for calculating the electric arc radiation energy of an electric power switch device, and a device. The method comprises: constructing a two-dimensional electric arc simulation model for an electric power switch device according to a fundamental equation of two-dimensional magnetohydrodynamics; performing iterative calculation in the two-dimensional electric arc simulation model according to the initial temperature and initial pressure of the electric power switch device, so as to obtain temperature data that meets iterative constraint conditions; and according to the temperature data and the electric arc radius of the electric power switch device, calculating the electric arc radiation energy of the electric power switch device. Radiation calculations of different regions of an electric arc are taken into consideration, such that a calculated radiation energy result has a high accuracy and a rational physical mechanism, the existing need to solve a radiation transport equation is avoided, the radiation calculation time is greatly reduced, the calculation efficiency is improved, and the method is more suitable for simulation calculation of electric arcs in the field of electric power industry. The technical problem of the results of electric arc calculations of existing circuit breakers obtained by means of using existing radiation transport equations being inaccurate due to the dependency of radiation of the circuit breakers on space and spectra is solved.

Description

Method, device and equipment for calculating arc radiation energy of power switchgear

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on June 5, 2023, with application number 202310657764.7 and invention name “A method, device and equipment for calculating arc radiation energy of power switching equipment”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of high-voltage circuit breaker arc technology, and in particular to a method, device and equipment for calculating arc radiation energy of a power switch device. Background Art

[0003] High-voltage circuit breakers are critical equipment in power systems, responsible for controlling their operation and providing fault protection. When a short circuit or other fault occurs in a power system, the high-voltage circuit breaker must quickly disconnect the faulty line to ensure stable operation of the rest of the system. During this process, an arc forms between the circuit breaker's arcing contacts. Whether this arc can be extinguished smoothly and promptly is crucial to the proper functioning of the circuit breaker and the reliable operation of the power system.

[0004] Arc simulation plays a vital role in the study of high-voltage circuit breaker interruption characteristics, so it is extremely necessary to establish an accurate arc model. The energy of the arc comes from the Joule heat generated when the current passes through the arc. The arc energy dissipation mainly occurs in three ways: conduction, convection, and radiation. Compared with conduction and convection, the maximum arc temperature in high-current high-voltage gas circuit breakers can reach tens of thousands of Kelvin, and the radiation energy dissipation mechanism is dominant. Therefore, establishing an arc radiation model is crucial for the simulation calculation of the entire arc interruption process. The radiation transport process in the arc is essentially the transport of photons, which can be described by the radiation transport equation: Where, I v is the spectral radiation intensity, K v is the spectral absorption coefficient, S is the radiation propagation direction, B v is Planck's constant.

[0005] The radiation characteristics of an arc can be derived by solving the radiation transport equation. However, in practical applications, there are two problems: First, the spatial and spectral dependence of radiation makes rigorous calculations of the radiation transfer equation difficult. Second, solving the radiation transport equation requires considering various atomic and molecular radiation mechanisms and processes, which is overly complex. Therefore, accurately calculating radiation by solving the radiation transport equation is very time-consuming and often unnecessary for industrial applications.

[0006] Summary of the Invention

[0007] The embodiments of the present application provide a method, apparatus and device for calculating arc radiation energy of an electric power switching device, which are used to solve the technical problem that the existing circuit breaker has inaccurate results obtained by using the existing radiation transport equation to calculate the arc due to its radiation dependence on space and spectrum.

[0008] In order to achieve the above objectives, the embodiments of the present application provide the following technical solutions:

[0009] In one aspect, a method for calculating arc radiation energy of a power switchgear is provided, comprising the following steps:

[0010] Obtain the structure, arc radius, initial temperature, and initial pressure of the power switchgear, and construct a two-dimensional arc simulation model with a two-dimensional axisymmetric geometry based on the basic equations of two-dimensional magnetohydrodynamics according to the structure of the power switchgear;

[0011] Performing iterative calculation in the two-dimensional arc simulation model according to the initial temperature and the initial pressure to obtain temperature data that meets iterative constraint conditions;

[0012] A first radiation energy of an arc core region and a second radiation energy of an arc edge region in the power switchgear are calculated based on the arc radius and the temperature data.

[0013] Preferably, calculating based on the arc radius and the temperature data to obtain the first radiation energy of the arc core region and the second radiation energy of the arc edge region in the power switchgear includes: calculating based on the arc radius and the temperature data using an arc radiation energy calculation formula to obtain the first radiation energy of the arc core region and the second radiation energy of the arc edge region in the power switchgear; the arc radiation energy calculation formula is: U=U0(T)K

[0014] Where T is the temperature data, K is the reduced pressure coefficient, β is the Stefan-Boltzmann constant of the power switchgear, U0(T) is the first radiation energy of the arc core area, U is the second radiation energy of the arc edge area, and R is the arc radius of the power switchgear.

[0015] Preferably, the reduced pressure coefficient is calculated based on the actual pressure of the power switchgear at the arc edge area and the pressure of the power switchgear at the arc core area, and the reduced pressure coefficient is not greater than 1.

[0016] Preferably, performing iterative calculation in the two-dimensional arc simulation model according to the initial temperature and the initial pressure to obtain temperature data that satisfies the iterative constraint condition includes:

[0017] Inputting the initial temperature and the initial pressure into the two-dimensional arc simulation model for calculation to obtain a first pressure of the power switchgear and an enthalpy value corresponding to the first pressure;

[0018] According to the relationship between temperature and enthalpy h in the two-dimensional arc simulation model, the temperature after one iteration is obtained by reverse deduction, and the temperature after one iteration is obtained by reverse deduction until the temperature difference between two adjacent iterations satisfies the iteration constraint condition, and the temperature obtained by the last iteration is used as the temperature data that satisfies the iteration constraint condition;

[0019] The iteration constraint condition is that the temperature difference is less than the threshold value, and the relationship between the temperature and enthalpy h is:

[0020] Where C P is the relationship coefficient between temperature and enthalpy h, h is the enthalpy value corresponding to the first pressure, P is the pressure iteratively calculated in the two-dimensional arc simulation model, and T is the temperature data.

[0021] Preferably, the power switch device is a compressed air type high voltage circuit breaker or a self-energized high voltage circuit breaker.

[0022] On the other hand, an arc radiation energy calculation device for a power switchgear is provided, comprising a model building module, an iterative calculation module, and an energy calculation module;

[0023] The model building module is used to obtain the structure, arc radius, initial temperature and initial pressure of the power switchgear, and build a two-dimensional arc simulation model with a two-dimensional axisymmetric geometry based on the basic equations of two-dimensional magnetohydrodynamics according to the structure of the power switchgear;

[0024] The iterative calculation module is used to perform iterative calculation in the two-dimensional arc simulation model according to the initial temperature and the initial pressure to obtain temperature data that meets the iterative constraint condition;

[0025] The energy calculation module is used to calculate, based on the arc radius and the temperature data, to obtain a first radiation energy of an arc core region and a second radiation energy of an arc edge region in the power switching device.

[0026] Preferably, the energy calculation module uses an arc radiation energy calculation formula to calculate according to the arc radius and the temperature data to obtain a first radiation energy of the arc core area and a second radiation energy of the arc edge area in the power switchgear; the arc radiation energy calculation formula is: U=U0(T)K

[0027] Where T is the temperature data, K is the reduced pressure coefficient, β is the Stefan-Boltzmann constant of the power switchgear, U0(T) is the first radiation energy of the arc core area, U is the second radiation energy of the arc edge area, and R is the arc radius of the power switchgear.

[0028] Preferably, the reduced pressure coefficient is calculated based on the actual pressure of the power switchgear at the arc edge area and the pressure of the power switchgear at the arc core area, and the reduced pressure coefficient is not greater than 1.

[0029] Preferably, the iterative calculation module includes an enthalpy value determination submodule and a temperature data determination submodule;

[0030] The enthalpy value determination submodule is configured to input the initial temperature and the initial pressure into the two-dimensional arc simulation model for calculation to obtain a first pressure of the power switchgear and an enthalpy value corresponding to the first pressure;

[0031] The temperature data determination submodule is used to reversely infer the relationship between temperature and enthalpy h in the two-dimensional arc simulation model to obtain the temperature after one iteration, and so on until the temperature difference between two adjacent iterative calculations meets the iteration constraint condition, and the temperature calculated in the last iterative calculation is used as the temperature data that meets the iteration constraint condition;

[0032] The iteration constraint condition is that the temperature difference is less than the threshold value, and the relationship between the temperature and enthalpy h is:

[0033] Where C P is the relationship coefficient between temperature and enthalpy h, h is the enthalpy value corresponding to the first pressure, P is the pressure iteratively calculated in the two-dimensional arc simulation model, and T is the temperature data.

[0034] In another aspect, a terminal device is provided, comprising a processor and a memory;

[0035] The memory is used to store program code and transmit the program code to the processor;

[0036] The processor is configured to execute the above-mentioned method for calculating arc radiation energy of the power switching device according to the instructions in the program code.

[0037] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages: the arc radiation energy calculation method, device and equipment of the power switching device, the method includes obtaining the structure, arc radius, initial temperature and initial pressure of the power switching device, and constructing a two-dimensional arc simulation model with two-dimensional axisymmetric geometry based on the basic equations of two-dimensional magnetohydrodynamics according to the structure of the power switching device; performing iterative calculation in the two-dimensional arc simulation model according to the initial temperature and initial pressure to obtain temperature data that meets the iterative constraint conditions; calculating according to the arc radius and temperature data to obtain the first radiation energy of the arc core area and the second radiation energy of the arc edge area in the power switching device. This method for calculating arc radiation energy for power switchgear constructs a two-dimensional arc simulation model of the power switchgear based on the basic two-dimensional magnetohydrodynamic equations. It then iteratively calculates the initial temperature and initial pressure of the power switchgear within the two-dimensional arc simulation model to obtain temperature data that satisfies iterative constraints. The arc radiation energy of the power switchgear is then calculated based on the temperature data and the arc radius of the power switchgear. Radiation calculations in different arc regions are considered separately, resulting in highly accurate and physically reasonable radiation energy results. This method avoids the need to solve existing radiation transport equations, significantly reduces radiation calculation time, and improves computational efficiency, making it more suitable for arc simulation calculations in the power industry. This method addresses the technical issue of inaccurate arc calculation results obtained using existing radiation transport equations due to the spatial and spectral dependence of existing circuit breakers. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0039] FIG1 is a flowchart of a method for calculating arc radiation energy of a power switchgear according to an embodiment of the present application;

[0040] FIG2 is a schematic diagram of the arc shape of a power switchgear in a method for calculating arc radiation energy of a power switchgear according to an embodiment of the present application;

[0041] 3 is a schematic diagram of arc energy distribution of a power switchgear in a method for calculating arc radiation energy of a power switchgear according to an embodiment of the present application;

[0042] 4 is a graph showing the axial distribution of arc temperature and pressure at a certain moment of arcing simulated by a two-dimensional arc simulation model in the arc radiation energy calculation method for a power switchgear according to an embodiment of the present application;

[0043] FIG5 is a framework flow chart of the arc radiation energy calculation device of the power switching device according to an embodiment of the present application. DETAILED DESCRIPTION

[0044] In order to make the purpose, features, and advantages of the invention of this application more obvious and easy to understand, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the embodiments described below are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0045] In the description of the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0046] In the embodiments of the present application, unless otherwise expressly specified or limited, the terms "installed," "connected," "connected," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections, electrical connections; direct connections, or indirect connections through an intermediate medium; and can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0047] The present invention provides a method, apparatus, and device for calculating arc radiation energy in power switchgear. These methods address the technical issue of inaccurate arc radiation energy calculations using existing radiation transport equations due to the spatial and spectral dependence of existing circuit breakers. These methods, apparatus, and devices are applicable to power switchgear such as compressed air high-voltage circuit breakers and self-energized high-voltage circuit breakers.

[0048] Example 1:

[0049] Figure 1 is a step flow chart of the method for calculating the arc radiation energy of the power switching device described in an embodiment of the present application, Figure 2 is a schematic diagram of the arc shape of the power switching device in the method for calculating the arc radiation energy of the power switching device described in an embodiment of the present application, and Figure 3 is a schematic diagram of the arc energy distribution of the power switching device in the method for calculating the arc radiation energy of the power switching device described in an embodiment of the present application.

[0050] As shown in FIG1 and FIG2 , an embodiment of the present application provides a method for calculating arc radiation energy of a power switchgear, comprising the following steps:

[0051] S1. Obtain the structure, arc radius, initial temperature, and initial pressure of the power switchgear, and construct a two-dimensional arc simulation model with a two-dimensional axisymmetric geometry based on the basic equations of two-dimensional magnetohydrodynamics according to the structure of the power switchgear.

[0052] It should be noted that the power switchgear can be selected as a compressed air type high-voltage circuit breaker or a self-energy type high-voltage circuit breaker. In step S1, the first step is to obtain the parameters of the power switchgear, including the structure of the power switchgear and the arc radius, initial temperature, initial pressure and other data; the second step is to construct a two-dimensional arc simulation model with a two-dimensional axisymmetric geometry based on the structure of the power switchgear and the basic equations of two-dimensional magnetohydrodynamics. In this embodiment, the arc radiation energy calculation method of the power switchgear can use Gambit software to complete the establishment of a two-dimensional arc simulation model based on the power switchgear. Among them, Gambit software is a software package designed to help analysts and designers establish and grid computational fluid dynamics (CFD) models and other scientific applications. In the constructed two-dimensional arc simulation model, the arc burning process of the power switchgear under the AC current working condition with an amplitude of 31.5KA at 50Hz is simulated, and its arc morphology is shown in Figure 2.

[0053] In the embodiment of the present application, if the arc of the power switchgear is an axisymmetric arc and the axial radiation process is negligible, only the arc radiation in the radial direction (radial direction) is considered. The arc radiation process is considered to be divided into two parts, as shown in Figure 3. The first part is the arc core area, which is close to the arc core. The temperature in the arc core area is relatively high, and the arc can be assumed to be in a nearly blackbody state. The second part is the arc edge area. The radiation effect of this arc edge area is relatively weak, and the blackbody radiation law cannot be used for calculation. Considering the large temperature gradient and pressure gradient at the arc edge.

[0054] FIG4 is a graph showing the axial distribution of arc temperature and pressure at a certain moment of arcing simulated by a two-dimensional arc simulation model in the arc radiation energy calculation method for the power switchgear according to an embodiment of the present application.

[0055] In the embodiment of the present application, based on the constructed two-dimensional arc simulation model, under the given geometric model structure of the power switchgear, the initial temperature and initial pressure are given as the input parameters of the two-dimensional arc simulation model, and the axial distribution of the first arc temperature and the first pressure of the power switchgear just after arcing is simulated, as shown in Figure 4. At this time, the arc radiation is calculated based on the first arc temperature and the first pressure at the time of arcing. The content of the basic equation of two-dimensional magnetohydrodynamics includes:

[0056] The mass conservation equation is:

[0057] The conservation equation of axial momentum is:

[0058] The radial momentum conservation equation is:

[0059] The energy conservation equation is:

[0060] The electromagnetic field equation is:

[0061] Where z is the axial direction, r is the radial direction, θ is the angular direction, t is the time / s, and ρ is the density / kg·m -3 , is the velocity vector, v is the radial velocity / m·s -1 , ω is the axial velocity / m·s -1 , μ l is the laminar viscosity / kg·m -1 ·s -1 , μ t is the turbulent viscosity / kg·m -1 ·s -1 , k l is the laminar thermal conductivity / W·m -1 ·K -1 , k t is the turbulent thermal conductivity / W·m -1 ·K -1 , U is the radiation energy / J·m -3 , h is enthalpy / J·kg -1 , c p is the specific heat at constant pressure / J·kg -1 ·K -1 , p is air pressure / Pa, σ is conductivity / S·m -1 , φ is the electric potential / V, B θ is the angular component of magnetic induction intensity / T·m -1 , J z is the axial current density / A·m -2 , J r is the radial current density A·m -2 , μ0 is the vacuum permeability / H·m -1 , is the sticky term, is the viscous diffusion term, m a is the ablation rate / kg·s -1 , v a is the incident velocity of ablation vapor / m·s -1 , h ais the ablation vapor enthalpy / J·kg -1 .

[0062] S2. Perform iterative calculations in a two-dimensional arc simulation model based on the initial temperature and initial pressure to obtain temperature data that meets the iterative constraint conditions.

[0063] It should be noted that in step S2, iterative calculation is performed based on the two-dimensional arc simulation model constructed in step S1 and the initial temperature and initial pressure obtained to obtain temperature data that meets the iterative constraint conditions.

[0064] In the embodiment of the present application, iterative calculation is performed in a two-dimensional arc simulation model based on the initial temperature and initial pressure, and the temperature data satisfying the iteration constraint conditions are obtained, including:

[0065] Inputting the initial temperature and initial pressure into a two-dimensional arc simulation model for calculation to obtain a first pressure of the power switchgear and an enthalpy value corresponding to the first pressure;

[0066] According to the relationship between temperature and enthalpy h in the two-dimensional arc simulation model, the temperature after one iteration is obtained. This is repeated until the temperature difference between two adjacent iterations meets the iteration constraint. The temperature obtained from the last iteration is used as the temperature data that meets the iteration constraint.

[0067] Among them, the iteration constraint condition is that the temperature difference is less than the threshold data, and the relationship between temperature and enthalpy h is:

[0068] Where C P is the relationship coefficient between temperature and enthalpy h, h is the enthalpy value corresponding to the first pressure, P is the pressure iteratively calculated in the two-dimensional arc simulation model, and T is the temperature data.

[0069] It should be noted that the threshold data can be 1e -6 , judged based on the temperature difference after each iteration. The temperature difference is mainly the difference between the current calculated temperature and the temperature calculated in the previous iteration. The initial pressure can be iterated based on the momentum conservation equation to obtain the pressure after one iteration. For temperature, the relationship between temperature and enthalpy h is first established through the relationship between temperature and enthalpy h, and a new enthalpy value is obtained by iteration (the iteration depends on the control equation on the left). The temperature after the iteration is then reversed based on the enthalpy value. In this embodiment, the threshold data can be set as required.

[0070] S3. Calculate based on the arc radius and temperature data to obtain a first radiation energy of the arc core region and a second radiation energy of the arc edge region in the power switchgear.

[0071] It should be noted that in step S3, the first radiation energy of the arc core region and the second radiation energy of the arc edge region of the power switchgear are calculated based on the temperature data calculated in step S2 and the arc radius obtained in step S1. The calculated first and second radiation energies are the arc simulation results of the arc radiation process. This method for calculating arc radiation energy for power switchgear is fast; the entire embodiment requires only 30 minutes of calculation using computer software.

[0072] The present application provides a method for calculating arc radiation energy of a power switchgear. The method comprises obtaining a structure, arc radius, initial temperature, and initial pressure of the power switchgear, constructing a two-dimensional arc simulation model with a two-dimensional axisymmetric geometry based on the basic equations of two-dimensional magnetohydrodynamics according to the structure of the power switchgear; performing iterative calculations in the two-dimensional arc simulation model according to the initial temperature and initial pressure to obtain temperature data that satisfies iterative constraints; and calculating a first radiation energy in an arc core region and a second radiation energy in an arc edge region of the power switchgear based on the arc radius and temperature data. The method for calculating arc radiation energy of a power switchgear comprises constructing a two-dimensional arc simulation model of the power switchgear according to the basic equations of two-dimensional magnetohydrodynamics, performing iterative calculations in the two-dimensional arc simulation model according to the initial temperature and initial pressure of the power switchgear to obtain temperature data that satisfies iterative constraints, and calculating the arc radiation energy of the power switchgear based on the temperature data and the arc radius of the power switchgear. The method considers radiation calculations in different arc regions separately, so that the calculated radiation energy result is highly accurate and reasonable in terms of physical mechanism, avoids solving existing radiation transport equations, greatly reduces the time of radiation calculation, improves calculation efficiency, and is more suitable for arc simulation calculations in the power industry. The invention solves the technical problem that the results of arc calculation using the existing radiation transport equation are inaccurate due to the dependence of the radiation of the existing circuit breaker on space and spectrum.

[0073] In one embodiment of the present application, obtaining, based on the arc radius and temperature data, a first radiation energy of an arc core region and a second radiation energy of an arc edge region in the power switchgear includes: calculating, based on the arc radius and temperature data, using an arc radiation energy calculation formula to obtain the first radiation energy of the arc core region and the second radiation energy of the arc edge region in the power switchgear; the arc radiation energy calculation formula is: U=U0(T)K

[0074] Where T is the temperature data, K is the reduced pressure coefficient, β is the Stefan-Boltzmann constant of the power switchgear, U0(T) is the first radiation energy of the arc core area, U is the second radiation energy of the arc edge area, and R is the arc radius of the power switchgear.

[0075] It should be noted that the primary radiation energy of the arc core region in power switchgear is calculated using the Stefan-Boltzmann law, which assumes that the total power radiated per unit area of ​​the arc surface in the arc core region is proportional to the fourth power of its thermodynamic temperature, T. The radiation from the arc edge region in power switchgear can be assumed to be proportional to the reduced pressure coefficient.

[0076] In an embodiment of the present application, the reduced pressure coefficient is calculated by the actual pressure of the power switching device in the arc edge area and the pressure of the power switching device in the arc core area, and the reduced pressure coefficient is not greater than 1.

[0077] It should be noted that the temperature at the arc edge is lower, so the pressure at the arc edge is lower than that in the arc core, and the equivalent pressure coefficient is less than or equal to 1. Since the pressure within the power switchgear can reflect the arc mass density, and the radiation process is closely related to density, the arc radiation energy calculation formula can be used to approximately simulate the weaker radiation process at the arc edge.

[0078] Example 2:

[0079] FIG5 is a framework flow chart of the arc radiation energy calculation device of the power switching device according to an embodiment of the present application.

[0080] As shown in FIG5 , an embodiment of the present application provides an arc radiation energy calculation device for a power switchgear, comprising a model building module 10 , an iterative calculation module 20 , and an energy calculation module 30 ;

[0081] The model building module 10 is used to obtain the structure, arc radius, initial temperature and initial pressure of the power switchgear, and build a two-dimensional arc simulation model with a two-dimensional axisymmetric geometry based on the basic equations of two-dimensional magnetohydrodynamics according to the structure of the power switchgear;

[0082] An iterative calculation module 20 is used to perform iterative calculations in a two-dimensional arc simulation model according to the initial temperature and the initial pressure to obtain temperature data that meets the iterative constraint conditions;

[0083] The energy calculation module 30 is used to calculate, based on the arc radius and temperature data, a first radiation energy of the arc core region and a second radiation energy of the arc edge region in the power switchgear.

[0084] In the embodiment of the present application, the energy calculation module 30 uses the arc radiation energy calculation formula to calculate the first radiation energy of the arc core area and the second radiation energy of the arc edge area in the power switchgear according to the arc radius and temperature data; the arc radiation energy calculation formula is: U=U0(T)K

[0085] Where T is the temperature data, K is the reduced pressure coefficient, β is the Stefan-Boltzmann constant of the power switchgear, U0(T) is the first radiation energy of the arc core area, U is the second radiation energy of the arc edge area, and R is the arc radius of the power switchgear.

[0086] In an embodiment of the present application, the reduced pressure coefficient is calculated by the actual pressure of the power switching device in the arc edge area and the pressure of the power switching device in the arc core area, and the reduced pressure coefficient is not greater than 1.

[0087] In the embodiment of the present application, the iterative calculation module 20 includes: an enthalpy value determination submodule and a temperature data determination submodule;

[0088] an enthalpy value determination submodule, configured to input the initial temperature and initial pressure into a two-dimensional arc simulation model for calculation to obtain a first pressure of the power switchgear and an enthalpy value corresponding to the first pressure;

[0089] The temperature data determination submodule is used to reversely infer the relationship between temperature and enthalpy h in the two-dimensional arc simulation model to obtain the temperature after one iteration, and so on until the temperature difference between two adjacent iterations meets the iteration constraint condition, and the temperature calculated by the last iteration is used as the temperature data that meets the iteration constraint condition;

[0090] Among them, the iteration constraint condition is that the temperature difference is less than the threshold data, and the relationship between temperature and enthalpy h is:

[0091] Where C P is the relationship coefficient between temperature and enthalpy h, h is the enthalpy value corresponding to the first pressure, P is the pressure iteratively calculated in the two-dimensional arc simulation model, and T is the temperature data.

[0092] It should be noted that the content of the module in the arc radiation energy calculation device of the power switching device corresponds to the content of the steps in the method of Example 1. The content of the steps of the method of Example 1 has been explained in Example 1, and the module content of the device of Example 2 will not be repeated in this embodiment.

[0093] Example 3:

[0094] An embodiment of the present application provides a terminal device, including a processor and a memory;

[0095] A memory, configured to store program codes and transmit the program codes to a processor;

[0096] The processor is configured to execute the above-mentioned method for calculating arc radiation energy of the power switching device according to instructions in the program code.

[0097] It should be noted that the processor is configured to execute the steps of the aforementioned embodiment of the method for calculating arc radiation energy of a power switchgear according to the instructions in the program code. Alternatively, the processor implements the functions of the modules / units in the aforementioned system / device embodiments when executing the computer program.

[0098] For example, a computer program may be divided into one or more modules / units, one or more of which are stored in a memory and executed by a processor to complete the present application. One or more modules / units may be a series of computer program instruction segments capable of performing specific functions, and the instruction segments are used to describe the execution process of the computer program in a terminal device.

[0099] Terminal devices can be computing devices such as desktop computers, laptops, PDAs, and cloud servers. Terminal devices may include, but are not limited to, processors and memory. Those skilled in the art will appreciate that this does not constitute a limitation on terminal devices and may include more or fewer components than shown, or a combination of certain components, or different components. For example, terminal devices may also include input / output devices, network access devices, buses, and the like.

[0100] The processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0101] Memory can be an internal storage unit of a terminal device, such as a hard drive or memory. It can also be an external storage device, such as a plug-in hard drive, a Smart Media Card (SMC), a Secure Digital (SD) card, or a flash memory card. Furthermore, memory can include both internal and external storage units. Memory is used to store computer programs and other programs and data required by the terminal device. Memory can also be used to temporarily store data that has been output or is about to be output.

[0102] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0103] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0104] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0105] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0106] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, 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, which is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0107] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for calculating arc radiation energy of a power switch device, characterized in that: The following steps are involved: The structure, arc radius, initial temperature and initial pressure of the power switch device are obtained, and a two-dimensional arc simulation model with two-dimensional axisymmetric geometry is constructed based on the basic equations of two-dimensional magnetohydrodynamics according to the structure of the power switch device; Performing iterative calculation in the two-dimensional arc simulation model according to the initial temperature and the initial pressure to obtain temperature data that meets iterative constraint conditions; The first radiation energy of the arc core region and the second radiation energy of the arc edge region in the power switch device are calculated based on the arc radius and the temperature data.

2. The arc radiation energy calculation method of the power switch device according to claim 1, characterized in that: Calculating according to the arc radius and the temperature data to obtain the first radiation energy of the arc core area and the second radiation energy of the arc edge area in the power switch device includes: calculating according to the arc radius and the temperature data using an arc radiation energy calculation formula to obtain the first radiation energy of the arc core area and the second radiation energy of the arc edge area in the power switch device; the arc radiation energy calculation formula is: U=U0(T)K Wherein, T is the temperature data, K is the reduced pressure coefficient, β is the Stefan-Boltzmann constant of the power switch device, U0(T) is the first radiation energy of the arc core area, U is the second radiation energy of the arc edge area, and R is the arc radius of the power switch device.

3. The arc radiation energy calculation method of the power switch device according to claim 2, characterized in that: The reduced pressure coefficient is calculated based on the actual pressure of the power switch device at the arc edge area and the pressure of the power switch device at the arc core area, and the reduced pressure coefficient is not greater than 1.

4. The arc radiation energy calculation method of the power switch device according to claim 1, characterized in that: Iterative calculation is performed in the two-dimensional arc simulation model according to the initial temperature and the initial pressure to obtain temperature data that meets the iteration constraint condition, including: The initial temperature and the initial pressure are input into the two-dimensional arc simulation model for calculation. Calculate and obtain a first pressure of the power switch device and an enthalpy value corresponding to the first pressure; According to the relationship between temperature and enthalpy h in the two-dimensional arc simulation model, the temperature after one iteration is obtained by reverse calculation, and the temperature after one iteration is obtained by reverse calculation until the temperature difference between two adjacent iterations satisfies the iteration constraint condition, and the temperature obtained by the last iteration calculation is used as the temperature data satisfying the iteration constraint condition; Wherein, the iteration constraint condition is that the temperature difference is less than the threshold data, and the relationship between the temperature and enthalpy h is: In the formula, C P is the relationship coefficient between temperature and enthalpy h, h is the enthalpy value corresponding to the first pressure, P is the pressure iteratively calculated in the two-dimensional arc simulation model, and T is the temperature data.

5. The arc radiation energy calculation method of the power switch device according to claim 1, characterized in that: The power switch device is a compressed air type high voltage circuit breaker or a self-energizing type high voltage circuit breaker.

6. An arc radiation energy calculation device for a power switchgear, characterized in that: It includes a model building module, an iterative calculation module and an energy calculation module; The model building module is used to obtain the structure, arc radius, initial temperature and initial pressure of the power switch device, and build a two-dimensional arc simulation model with two-dimensional axisymmetric geometry based on the basic equations of two-dimensional magnetohydrodynamics according to the structure of the power switch device; The iterative calculation module is used to perform iterative calculation in the two-dimensional arc simulation model according to the initial temperature and the initial pressure to obtain temperature data that meets the iterative constraint condition; The energy calculation module is used to calculate, according to the arc radius and the temperature data, to obtain a first radiation energy of an arc core region and a second radiation energy of an arc edge region in the power switch device.

7. The arc radiation energy calculation device for power switchgear according to claim 6, characterized in that: The energy calculation module uses an arc radiation energy calculation formula to calculate according to the arc radius and the temperature data to obtain a first radiation energy of an arc core area and a second radiation energy of an arc edge area in the power switch device; the arc radiation energy calculation formula is: U=U0(T)K Where T is the temperature data, K is the reduced pressure coefficient, β is the Stefan-Boltzmann constant of the power switchgear, U0(T) is the first radiation energy of the arc core area, and U is the arc edge The second radiation energy in the edge area, R is the arc radius of the power switching device.

8. The arc radiation energy calculation device for power switchgear according to claim 7, characterized in that: The reduced pressure coefficient is calculated based on the actual pressure of the power switch device at the arc edge area and the pressure of the power switch device at the arc core area, and the reduced pressure coefficient is not greater than 1.

9. The arc radiation energy calculation device for power switchgear according to claim 6, characterized in that: The iterative calculation module includes: an enthalpy value determination submodule and a temperature data determination submodule; The enthalpy value determination submodule is used to input the initial temperature and the initial pressure into the two-dimensional arc simulation model for calculation to obtain a first pressure of the power switch device and an enthalpy value corresponding to the first pressure; The temperature data determination submodule is used to reversely infer the relationship between temperature and enthalpy h in the two-dimensional arc simulation model to obtain the temperature after one iteration, and so on until the temperature difference calculated between two adjacent iterations meets the iteration constraint condition, and the temperature calculated in the last iteration is used as the temperature data that meets the iteration constraint condition; Wherein, the iteration constraint condition is that the temperature difference is less than the threshold data, and the relationship between the temperature and enthalpy h is: In the formula, C P is the relationship coefficient between temperature and enthalpy h, h is the enthalpy value corresponding to the first pressure, P is the pressure iteratively calculated in the two-dimensional arc simulation model, and T is the temperature data.

10. A terminal device, characterized in that: including a processor and a memory; The memory is used to store program codes and transmit the program codes to the processor; The processor is used to execute the arc radiation energy calculation method of the power switch device according to any one of claims 1-5 according to the instructions in the program code.

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