Method and device for establishing a single-phase earth fault arc model

Abstract

The application relates to a method and device for establishing a single-phase grounding fault arc model. The method comprises: collecting arc data and load data in an arc stage; and establishing an arc model according to the arc data and the load data, which comprises: obtaining an arc starting resistance according to arc current, arc voltage, load current and load voltage in an arc starting stage; obtaining an arc burning resistance according to arc current, arc voltage, load current and load voltage in a steady-state arc burning stage; and obtaining an arc extinguishing resistance according to arc current, arc voltage, load current and load voltage in an arc extinguishing stage. The application establishes the arc model in three stages, i.e., the arc starting stage, the steady-state arc burning stage and the arc extinguishing stage, so that the arc model in each stage is more in line with the arc characteristics of the respective stage, thereby better simulating an actual single-phase grounding fault arc.

Description

Technical Field

[0001] This application relates to the field of power fault technology, and in particular to a method and apparatus for establishing a single-phase ground fault arc model. Background Technology

[0002] With the rapid advancement of urbanization, cables have become the main form of power transmission in urban power distribution networks, and the length and transmission capacity of single-circuit cable lines are constantly increasing with the growing urban electricity load. Compared to traditional overhead lines, cable lines are usually laid in multiple circuits within the same channel. This makes it extremely easy for a fault in one cable line to spread to other cable lines. In severe cases, it may even cause the loss of the entire cable channel, resulting in serious large-scale power outages and seriously affecting the reliability and quality of power supply services.

[0003] The frequency of faults in distribution cable lines is higher than that in main grid cable lines, and single-phase grounding faults are the main type of fault in distribution cable lines. Under the current widespread use of resonant grounding in distribution networks, if a single-phase grounding fault is transient, operation can be quickly restored, improving the reliability of the distribution network. However, if the fault is permanent, the arc caused by the single-phase grounding can persist and potentially ignite other equipment such as optical cables, secondary cables, and main grid cables laid in cable tunnels, leading to an escalation of the accident. Therefore, it is necessary to study the arc during single-phase grounding faults.

[0004] In related technologies, existing arc models, when describing the arc characteristics of single-phase ground faults, treat the arc as a fixed resistor, completely ignoring the complex physical changes of the arc at different stages. For example, in the arc initiation stage, the arc undergoes intense gas ionization and electron emission processes from nothing to something, and its resistance characteristics are not constant; in the steady-state arc burning stage, the stability of the arc is affected by various factors, such as load current and voltage, which traditional models fail to effectively consider; in the arc extinction stage, the plasma decay process plays a crucial role in the arc resistance, but traditional models lack accurate descriptions of this. These limitations make it difficult for existing arc models to accurately simulate actual single-phase ground fault arcs, and they cannot provide a reliable basis for power system fault analysis and optimized design of protection devices.

[0005] Therefore, it is necessary to provide a new technical solution to improve one or more of the problems existing in the above solutions.

[0006] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0007] The purpose of this application is to provide a method and apparatus for establishing a single-phase ground fault arc model, thereby overcoming, to at least to some extent, one or more problems caused by the limitations and defects of related technologies.

[0008] According to a first aspect of the embodiments of this application, a method for establishing a single-phase ground fault arc model is provided, the method comprising:

[0009] The system collects arc data and load data during the arc phase, wherein the arc phase includes the arc initiation phase, the steady-state arc burning phase, and the total arc extinction phase; the arc data includes arc current and arc voltage; and the load data includes load current and load voltage.

[0010] An arc model is established based on the arc data and the load data; wherein, the step of establishing the arc model based on the arc data and the load data includes:

[0011] For the arc initiation stage, the arc initiation resistance is obtained based on the arc current, arc voltage, load current, and load voltage of the arc initiation stage.

[0012] For the steady-state arcing stage, the arcing resistance is obtained based on the arc current, arc voltage, load current, and load voltage of the steady-state arcing stage.

[0013] For the arc extinction stage, the arc extinction resistance is obtained based on the arc current, arc voltage, load current, and load voltage of the arc extinction stage.

[0014] In embodiments of this application, the step of obtaining the arc initiation resistance based on the arc current, arc voltage, and load current during the arc initiation stage includes:

[0015] The initial arc-starting resistance is obtained from the initial arc-starting voltage and initial arc-starting current.

[0016] The minimum resistance after the arc is fully ionized is obtained from the minimum voltage and the minimum current after the arc is fully ionized.

[0017] The arc initiation resistance is obtained based on the initial arc initiation resistance, the minimum resistance after the arc is fully ionized, the load current during the arc initiation stage, and the load voltage during the arc initiation stage.

[0018] In the embodiments of this application, the calculation formula for the arc-starting resistance is as follows:

[0019]

[0020] In the formula, U1 represents the initial resistance for arc initiation, I1 represents the initial current for arc initiation, and U 1min I represents the minimum voltage after the arc has been fully ionized.1min U represents the minimum current after the arc has been fully ionized. L1 I represents the load voltage during the arc initiation phase. L1 Let represent the load current during the arc initiation phase, k1 represent the load factor during the arc initiation phase, α represent the resistance attenuation factor, t1 represent the arc initiation time, and R... L This indicates the load reference resistance.

[0021] In the embodiments of this application, the step of obtaining the arc resistance based on the arc current, arc voltage, and load current of the steady-state arcing stage includes:

[0022] The arc resistance during the steady-state arcing stage is obtained based on the arc voltage and arc current during the steady-state arcing stage.

[0023] The arc resistance is obtained based on the arc resistance, load current, and load voltage during the steady-state arcing phase.

[0024] In the embodiments of this application, the calculation formula for the arc-ignition resistor is as follows:

[0025]

[0026] In the formula, U1 represents the arc voltage during the steady-state arcing stage, I1 represents the arc current during the steady-state arcing stage, and U L2 I represents the load voltage during the steady-state arcing phase. L2 The table represents the load current during the steady-state arcing stage, and k2 represents the load factor during the steady-state arcing stage.

[0027] In the embodiments of this application, the step of obtaining the arc-extinguishing resistance based on the arc current, arc voltage, load current, and load voltage during the arc-extinguishing stage includes:

[0028] The instantaneous minimum arc voltage and the instantaneous minimum arc current during the arc extinction phase are used to obtain the instantaneous minimum resistance during the arc extinction phase.

[0029] The instantaneous maximum resistance during the arc extinction phase is obtained based on the instantaneous maximum arc voltage and the instantaneous maximum arc current during the arc extinction phase.

[0030] The arc-extinguishing resistance is obtained based on the instantaneous minimum resistance, instantaneous maximum resistance, load current, and load current during the arc-extinguishing phase.

[0031] In the embodiments of this application, the calculation formula for the arc-extinguishing resistor is as follows:

[0032]

[0033] In the formula, U min I represents the instantaneous minimum arc voltage during the arc extinction phase. min U represents the instantaneous minimum arc current during the arc extinction phase. max I represents the instantaneous maximum arc voltage during the arc extinction phase. max U represents the instantaneous maximum arc current during the arc extinction phase, β represents the attenuation coefficient, t3 represents the arc extinction time, k3 represents the load factor during the arc extinction phase, and U L3 I represents the load voltage during the arc extinction phase. L3 This represents the load current during the arc extinction phase.

[0034] In the embodiments of this application, the electric arc model is:

[0035]

[0036] In the formula, t represents the arc time.

[0037] In embodiments of this application, after the step of collecting arc data and load data during the arc phase, the method further includes:

[0038] The arc data and the load data are preprocessed to obtain the preprocessed arc data.

[0039] In the embodiments of this application, the acquisition module is used to acquire arc data during the arc stage, wherein the arc stage includes the arc initiation stage, the steady-state arc burning stage and the total arc extinction stage, and the arc data includes arc current, arc voltage, load current and load voltage.

[0040] A module is established to establish an arc model based on the arc data and the load data; wherein, the step of establishing the arc model based on the arc data and the load data includes:

[0041] For the arc initiation stage, the arc initiation resistance is obtained based on the arc current, arc voltage, load current, and load voltage of the arc initiation stage.

[0042] For the steady-state arcing stage, the arcing resistance is obtained based on the arc current, arc voltage, load current, and load voltage of the steady-state arcing stage.

[0043] For the arc extinction stage, the arc extinction resistance is obtained based on the arc current, arc voltage, load current, and load voltage of the arc extinction stage.

[0044] The technical solutions provided by the embodiments of this application may include the following beneficial effects:

[0045] In one embodiment of this application, the above method, on the one hand, collects arc data and load data corresponding to the arc initiation stage, steady-state arc burning stage, and complete extinction stage, covering the complete process of arc generation to extinction, making the collected data rich and comprehensive, providing rich and comprehensive data for subsequent arc model building. On the other hand, since the arcs in different arc stages are different, the arc model is built in stages from the three arc stages of arc initiation, steady-state arc burning stage, and arc extinction stage, making the arc model of each arc stage more consistent with the arc characteristics of its respective stage, thereby better simulating the actual single-phase ground fault arc, and providing a more reliable basis for subsequent research and analysis of single-phase ground faults.

[0046] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0047] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0048] Figure 1 The flowchart illustrates the steps of a method for establishing a single-phase ground fault arc model in an exemplary embodiment of this application.

[0049] Figure 2 The diagram schematically illustrates a block diagram of an apparatus for establishing a single-phase ground fault arc model according to an exemplary embodiment of this application. Detailed Implementation

[0050] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided to make this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0051] Furthermore, the accompanying drawings are merely illustrative of this application and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0052] This example implementation first provides a method for establishing a single-phase ground fault arc model. (Reference) Figure 1 As shown, the method may include steps S101 to S102.

[0053] Step S101: Collect arc data and load data during the arc stage. The arc stage includes the arc initiation stage, the steady-state arc burning stage, and the complete arc extinction stage. The arc data includes arc current and arc voltage, and the load data includes load current and load voltage.

[0054] Step S102: Establish an arc model based on arc data and load data; wherein, the step of establishing an arc model based on arc data and load data includes:

[0055] For the arc initiation stage, the arc initiation resistance is obtained based on the arc current, arc voltage, load current, and load voltage during the arc initiation stage.

[0056] For the steady-state arcing stage, the arcing resistance is obtained based on the arc current, arc voltage, load current, and load voltage during the steady-state arcing stage.

[0057] For the arc extinction stage, the arc extinction resistance is obtained based on the arc current, arc voltage, load current, and load voltage during the arc extinction stage.

[0058] In one embodiment of this application, the above method, on the one hand, collects arc data and load data corresponding to the arc initiation stage, steady-state arc burning stage, and complete extinction stage, covering the complete process of arc generation to extinction, making the collected data rich and comprehensive, providing rich and comprehensive data for subsequent arc model building. On the other hand, since the arcs in different arc stages are different, the arc model is built in stages from the three arc stages of arc initiation, steady-state arc burning stage, and arc extinction stage, making the arc model of each arc stage more consistent with the arc characteristics of its respective stage, thereby better simulating the actual single-phase ground fault arc, and providing a more reliable basis for subsequent research and analysis of single-phase ground faults.

[0059] Below, we will refer to Figure 1The steps of the method described above in this example embodiment will be explained in more detail.

[0060] In step S101, an electric arc phenomenon occurs when a cable grounding fault occurs. The arc phenomenon generally involves three stages: the arc initiation stage, the steady-state arc burning stage, and the complete arc extinction stage. The arc initiation stage is generally the stage in which the arc is generated, the steady-state arc burning stage is generally the stage in which the arc burns steadily, and the complete arc extinction stage is generally the stage in which the arc is extinguished. Therefore, in studying the establishment of the arc model for a single-phase grounding fault, this application divides the arc stages into the arc initiation stage, the steady-state arc burning stage, and the complete arc extinction stage, and collects the arc data and load data corresponding to each arc stage.

[0061] It should be noted that the arc data and load data collected in this application can be obtained from power system monitoring equipment or experimental testing platforms, etc. This application does not impose any restrictions on this.

[0062] Furthermore, arc data includes arc current and arc voltage, while load data includes load current and load voltage. Therefore, collecting arc and load data corresponding to each arc stage means collecting the arc current, arc voltage, load current, and load voltage corresponding to each arc stage. The collected arc and load data cover the complete process from arc generation to extinction, making the collected arc and load data rich and comprehensive, providing a data foundation for subsequent arc model building.

[0063] In step S102, establishing the arc model based on the arc data and load data corresponding to each arc stage includes the following:

[0064] In one embodiment, the step of obtaining the arc initiation resistance based on the arc current, arc voltage, and load current during the arc initiation stage includes:

[0065] The initial arc-starting resistance is obtained from the initial arc-starting voltage and initial arc-starting current.

[0066] The minimum resistance after the arc is fully ionized is obtained from the minimum voltage and the minimum current after the arc is fully ionized.

[0067] The arc initiation resistance is obtained based on the initial arc initiation resistance, the minimum resistance after the arc is fully ionized, the load current during the arc initiation stage, and the load voltage during the arc initiation stage.

[0068] Understandably, the initial arc resistance and the minimum resistance after the arc is fully ionized can better reflect the resistance variation during the arc initiation stage. Furthermore, based on the influence of the load on the arc initiation resistance in actual circuits, incorporating the load current and load voltage during the arc initiation stage into the determination process makes the arc model during the arc initiation stage more accurate, improving its practicality and reliability.

[0069] Furthermore, the formula for calculating the arc-starting resistance is as follows:

[0070]

[0071] In the formula, U1 represents the initial resistance for arc initiation, I1 represents the initial current for arc initiation, and U 1min I represents the minimum voltage after the arc has been fully ionized. 1min U represents the minimum current after the arc has been fully ionized. L1 I represents the load voltage during the arc initiation phase. L1 Let represent the load current during the arc initiation phase, k1 represent the load factor during the arc initiation phase, α represent the resistance attenuation factor, t1 represent the arc initiation time, and R... L This indicates the load reference resistance.

[0072] It is understandable that the arc model in the arc initiation stage can be determined based on the above formulas (1) and (2), namely the arc initiation resistance, which reflects the generation of the arc.

[0073] It should be noted that the load reference resistance is the theoretical resistance of the load. Because arcing in the circuit affects the actual resistance of the load, the load factor can be determined based on both the actual and theoretical resistances. The load factor during the arcing phase affects the arcing resistance during this phase. Therefore, when determining the arcing resistance during the arcing phase, the load factor should be taken into account to make the determined arcing resistance more accurate and reliable.

[0074] In one embodiment, the step of obtaining the arc resistance based on the arc current, arc voltage, and load current during the steady-state arcing stage includes:

[0075] The arc resistance during the steady-state arcing stage is obtained based on the arc voltage and arc current during the steady-state arcing stage.

[0076] The arc resistance is obtained based on the arc resistance, load current, and load voltage during the steady-state arcing phase.

[0077] It is understandable that the load affects the arc model not only during the arc initiation stage but also during the steady-state arcing stage. Therefore, this application incorporates the load current and load voltage during the steady-state arcing stage into the determination process of the arcing resistance, based on the influence of the load on the arcing resistance in the actual circuit. This makes the arc model during the steady-state arcing stage more consistent with reality, improving its practicality and reliability.

[0078] Furthermore, the formula for calculating the arc resistance is as follows:

[0079]

[0080] In the formula, U1 represents the arc voltage during the steady-state arcing stage, I1 represents the arc current during the steady-state arcing stage, and U L2 I represents the load voltage during the steady-state arcing phase. L2 The table represents the load current during the steady-state arcing stage, and k2 represents the load factor during the steady-state arcing stage.

[0081] It is understandable that the arc model of the steady-state arc stage can be determined based on the above formulas (3) and (4), namely the arc resistance, which can reflect the steady-state combustion process of the arc.

[0082] It should be noted that the load factor during the steady-state arcing stage affects the arcing resistance during this stage. Therefore, when determining the arcing resistance during the steady-state arcing stage, the corresponding load factor should be taken into account to make the determined arcing resistance during the steady-state arcing stage more realistic and reliable.

[0083] In one embodiment, the step of obtaining the arc-extinguishing resistor based on the arc current, arc voltage, load current, and load voltage during the arc-extinguishing phase includes:

[0084] The instantaneous minimum arc voltage and instantaneous minimum arc current during the arc extinction phase are used to obtain the instantaneous minimum resistance during the arc extinction phase.

[0085] The instantaneous maximum arc voltage and instantaneous maximum arc current during the arc extinction phase are used to obtain the instantaneous maximum resistance during the arc extinction phase.

[0086] The arc-extinguishing resistance is obtained based on the instantaneous minimum resistance, instantaneous maximum resistance, load current, and load current during the arc-extinguishing phase.

[0087] Understandably, after the arc enters the extinction stage, considering the fluctuation range of the arc voltage and the influence of the load conditions on the extinction resistance during the extinction stage, this application determines the extinction resistance by using the instantaneous minimum arc voltage, the instantaneous minimum current, and the load current and load voltage during the extinction stage, thereby improving the simulation accuracy of the single-phase ground fault arc model during the extinction stage.

[0088] Furthermore, the formula for calculating the arc-extinguishing resistor is as follows:

[0089]

[0090] In the formula, U min I represents the instantaneous minimum arc voltage during the arc extinction phase. min U represents the instantaneous minimum arc current during the arc extinction phase. max I represents the instantaneous maximum arc voltage during the arc extinction phase. max U represents the instantaneous maximum arc current during the arc extinction phase, β represents the attenuation coefficient, t3 represents the arc extinction time, k3 represents the load factor during the arc extinction phase, and U L3 I represents the load voltage during the arc extinction phase. L3 This represents the load current during the arc extinction phase.

[0091] It should be noted that the arc model in the arc extinguishing stage, namely the arc extinguishing resistance, can be determined by the above formulas (5) and (6). The arc extinguishing resistance can reflect the arc extinguishing process.

[0092] In one embodiment, the electric arc model is as follows:

[0093]

[0094] In the formula, t represents the arc time.

[0095] Understandably, the arc model includes the arc initiation resistance during the arc initiation period, the arc burning resistance during the arc combustion period, and the arc extinguishing resistance during the arc extinction period. The arc initiation resistance, arc burning resistance, and arc extinguishing resistance correspond to the arc initiation stage, the steady-state arc combustion stage, and the arc extinction stage, respectively, completely covering the entire process from arc generation to extinction. Therefore, the arc model can comprehensively reflect the changes in resistance characteristics at different arc stages.

[0096] Analyzing the resistance characteristics at different stages of an electric arc facilitates the identification of the timing and type of the fault. For example, abnormal arc initiation resistance can indicate changes in arc initiation conditions, changes in arc burning resistance reflect energy loss and stability during arc burning, and the characteristics of arc extinguishing resistance relate to the residual effects after the fault ends, providing rich and targeted information for fault analysis.

[0097] It should be noted that studying the resistance characteristics at different stages of the arc facilitates subsequent improvements to the arc characteristics. For example, improving cable materials and optimizing the arc initiation resistance to reduce arc initiation impact, and optimizing the arc extinguishing resistance to achieve faster and more complete arc extinguishing, thereby improving the safety of the power system.

[0098] In one embodiment, after the step of acquiring arc data and load data during the arc phase, the method further includes:

[0099] The arc data and load data are preprocessed to obtain preprocessed arc data and load data.

[0100] Understandably, after collecting the arc and load data, this application requires preprocessing to obtain accurate arc and load data. Preprocessing mainly includes data cleaning and data normalization. During data cleaning, filtering algorithms (such as mean filtering, median filtering, or wavelet filtering) are generally used to remove noise, spikes, and other outliers from the data, ensuring data accuracy. During data normalization, the min-max normalization method is generally used to map data of different ranges and types to the same scale, making the data comparable and facilitating subsequent model training and learning.

[0101] It should be noted that data cleaning and data normalization can be understood with reference to existing technologies, and this application will not elaborate on them.

[0102] It should be noted that although the steps of the method in this application are described in a specific order in the accompanying drawings, this does not require or imply that these steps must be performed in that specific order, or that all the steps shown must be performed to achieve the desired result. Additional or alternative steps may be omitted, multiple steps may be combined into one step, and / or a step may be broken down into multiple steps. Furthermore, it is readily understood that these steps may be executed synchronously or asynchronously, for example, in multiple modules / processes / threads.

[0103] Furthermore, this example embodiment also provides an apparatus for establishing a single-phase ground fault arc model. (See reference...) Figure 2As shown, the device 200 may include a data acquisition module 210 and a data creation module 220. The data acquisition module 210 is used to acquire arc data during the arc phase, which includes an arc ignition phase, a steady-state arc burning phase, and a complete arc extinction phase. The arc data includes arc current, arc voltage, load current, and load voltage. The data creation module 220 is used to create an arc model based on the arc data and load data. The step of creating the arc model based on the arc data and load data includes: for the arc ignition phase, obtaining the arc ignition resistance based on the arc current, arc voltage, load current, and load voltage; for the steady-state arc burning phase, obtaining the arc burning resistance based on the arc current, arc voltage, load current, and load voltage; and for the arc extinction phase, obtaining the arc extinction resistance based on the arc current, arc voltage, load current, and load voltage.

[0104] In one embodiment, the device further includes:

[0105] The first submodule is used to obtain the initial arc resistance based on the initial arc voltage and initial arc current.

[0106] The minimum resistance after the arc is fully ionized is obtained from the minimum voltage and the minimum current after the arc is fully ionized.

[0107] The arc initiation resistance is obtained based on the initial arc initiation resistance, the minimum resistance after the arc is fully ionized, the load current during the arc initiation stage, and the load voltage during the arc initiation stage.

[0108] In one embodiment, the device further includes:

[0109] The second submodule is used to obtain the arc resistance during the steady-state arcing stage based on the arc voltage and arc current during the steady-state arcing stage.

[0110] The arc resistance is obtained based on the arc resistance, load current, and load voltage during the steady-state arcing phase.

[0111] In one embodiment, the device further includes:

[0112] The third submodule is used to obtain the instantaneous minimum resistance during the arc extinction phase based on the instantaneous minimum arc voltage and the instantaneous minimum arc current during the arc extinction phase.

[0113] The instantaneous maximum arc voltage and instantaneous maximum arc current during the arc extinction phase are used to obtain the instantaneous maximum resistance during the arc extinction phase.

[0114] The arc-extinguishing resistance is obtained based on the instantaneous minimum resistance, instantaneous maximum resistance, load current, and load current during the arc-extinguishing phase.

[0115] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0116] It should be noted that although several modules or units for the device used to perform actions have been mentioned in the detailed description above, this division is not mandatory. In fact, according to the embodiments of this application, the features and functions of two or more modules or units described above can be embodied in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided and embodied by multiple modules or units. Components shown as modules or 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 the modules can be selected to achieve the purpose of this application according to actual needs. Those skilled in the art can understand and implement this without any inventive effort.

[0117] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein.

Claims

1. A method for establishing a single-phase grounding fault arc model, characterized in that, The method includes: The system collects arc data and load data during the arc phase, wherein the arc phase includes the arc initiation phase, the steady-state arc burning phase, and the total arc extinction phase; the arc data includes arc current and arc voltage; and the load data includes load current and load voltage. An arc model is established based on the arc data and the load data; wherein, the step of establishing the arc model based on the arc data and the load data includes: For the arc initiation stage, the arc initiation resistance is obtained based on the arc current, arc voltage, load current, and load voltage of the arc initiation stage. For the steady-state arcing stage, the arcing resistance is obtained based on the arc current, arc voltage, load current, and load voltage of the steady-state arcing stage. For the arc extinction stage, the arc extinction resistance is obtained based on the arc current, arc voltage, load current, and load voltage of the arc extinction stage. The step of obtaining the arc initiation resistance based on the arc current, arc voltage, and load current during the arc initiation stage includes: The initial arc-starting resistance is obtained from the initial arc-starting voltage and initial arc-starting current. The minimum resistance after the arc is fully ionized is obtained from the minimum voltage and the minimum current after the arc is fully ionized. The arc initiation resistance is obtained based on the initial arc initiation resistance, the minimum resistance after the arc is fully ionized, the load current during the arc initiation stage, and the load voltage during the arc initiation stage. The step of obtaining the arc resistance based on the arc current, arc voltage, and load current during the steady-state arcing stage includes: The arc resistance during the steady-state arcing stage is obtained based on the arc voltage and arc current during the steady-state arcing stage. The arc resistance is obtained based on the arc resistance, load current, and load voltage during the steady-state arcing phase. The step of obtaining the arc-extinguishing resistance based on the arc current, arc voltage, load current, and load voltage during the arc-extinguishing stage includes: The instantaneous minimum arc voltage and the instantaneous minimum arc current during the arc extinction phase are used to obtain the instantaneous minimum resistance during the arc extinction phase. The instantaneous maximum resistance during the arc extinction phase is obtained based on the instantaneous maximum arc voltage and the instantaneous maximum arc current during the arc extinction phase. Based on the instantaneous minimum resistance and instantaneous maximum resistance during the arc extinction phase, The arc-extinguishing resistor is obtained from the load current during the arc-extinguishing phase and the load current during the arc-extinguishing phase.

2. The method for establishing a single-phase grounding fault arc model according to claim 1, characterized in that, The formula for calculating the arc-starting resistance is as follows: （1） （2） In the formula, This represents the initial voltage at which the arc begins. This represents the initial current for arc initiation. This represents the minimum voltage required for the arc to be fully ionized. This represents the minimum current after the arc has been fully ionized. This represents the load voltage during the arc initiation phase. This represents the load current during the arc initiation phase. This represents the load factor during the arc initiation phase. Indicates the resistance attenuation coefficient. Indicates the arc initiation time. This indicates the load reference resistance.

3. The method for establishing a single-phase grounding fault arc model according to claim 2, characterized in that, The formula for calculating the arc resistance is: （3）； （4） In the formula, This represents the arc voltage during the steady-state arcing phase. This represents the arc current during the steady-state arcing phase. This represents the load voltage during the steady-state arcing phase. The load current during the steady-state arcing stage. This represents the load factor during the steady-state arcing stage.

4. The method for establishing a single-phase grounding fault arc model according to claim 3, characterized in that, The formula for calculating the arc-extinguishing resistor is as follows: （5） （6） In the formula, This represents the instantaneous minimum arc voltage during the arc extinction phase. This represents the instantaneous minimum arc current during the arc extinction phase. This represents the instantaneous maximum arc voltage during the arc extinction phase. This represents the instantaneous maximum arc current during the arc extinction phase. Indicates the attenuation coefficient. Indicates the arc extinction time. This represents the load factor during the arc extinction phase. This represents the load voltage during the arc extinction phase. This represents the load current during the arc extinction phase.

5. The method for establishing a single-phase grounding fault arc model according to claim 4, characterized in that, The electric arc model is as follows: （7）； In the formula, t represents the arc time.

6. The method for establishing a single-phase grounding fault arc model according to claim 1, characterized in that, Following the steps of collecting arc data and load data during the arc phase, the method further includes: The arc data and the load data are preprocessed to obtain the preprocessed arc data and the load data.

7. A device for establishing a single-phase ground fault arc model, characterized in that, The apparatus for establishing a single-phase ground fault arc model according to any one of claims 1 to 6 includes: The acquisition module is used to acquire arc data and load data during the arc phase, wherein the arc phase includes the arc initiation phase, the steady-state arc burning phase, and the total arc extinction phase; the arc data includes arc current and arc voltage; and the load data includes load current and load voltage. A module is established to establish an arc model based on the arc data and the load data; wherein, the step of establishing the arc model based on the arc data and the load data includes: For the arc initiation stage, the arc initiation resistance is obtained based on the arc current, arc voltage, load current, and load voltage of the arc initiation stage. For the steady-state arcing stage, the arcing resistance is obtained based on the arc current, arc voltage, load current, and load voltage of the steady-state arcing stage. For the arc extinction stage, the arc extinction resistance is obtained based on the arc current, arc voltage, load current, and load voltage of the arc extinction stage.

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