Method, system and medium for evaluating lightning impulse current diffusion performance of grounding device

Abstract

The present invention discloses a method, system and medium for evaluating the lightning impulse dissipation performance of a grounding device, which obtain environmental parameters and impulse grounding resistance of the grounding device; calculate a subsequent impulse coefficient based on the environmental parameters and in combination with the time interval of lightning impulses; calculate a subsequent impulse resistance based on the subsequent impulse coefficient and the impulse grounding resistance; compare the impulse grounding resistance and the subsequent impulse grounding resistance with a grounding resistance safety threshold, respectively, and predict the safety performance of the grounding device based on the comparison results of the two; the beneficial effect of the present invention is that by setting a subsequent impulse coefficient related to the number of lightning impulses and environmental factors, and simultaneously judging the lightning impulse dissipation performance safety of the grounding device through the subsequent impulse resistance and the grounding impulse resistance calculated by the subsequent impulse coefficient, the error in the lightning impulse dissipation performance evaluation of the grounding device can be reduced, and the accuracy of the evaluation result is improved.

Description

Technical Field

[0001] The present invention relates to the field of high voltage and insulation technology, and in particular to a method, system and medium for evaluating the lightning impulse dissipation performance of a grounding device. Background Art

[0002] Traditional methods for evaluating the surge dissipation performance of grounding systems typically use a surge grounding resistance equivalent to the surge coefficient as an evaluation metric. This is calculated by multiplying the grounding system's power frequency grounding resistance by the surge coefficient equivalent surge grounding resistance. The calculated surge grounding resistance is then compared with a standard threshold to determine whether the grounding system meets safety grounding requirements. However, in actual operation, even grounding systems that meet regulatory requirements still experience damage to electrical equipment when lightning strikes dissipate surges. This demonstrates the limitations of traditional evaluation methods, particularly in their failure to account for the subsequent voltage rise associated with continuous surge discharges.

[0003] Actual lightning has the characteristic of one breakdown and multiple discharges. During the continuous impulse discharge process, the preceding impulse discharge will form an obvious discharge channel in the ground. When the time interval between subsequent impulse discharges is large, the preceding impulse discharge channel will become a high-resistance channel of lightning rock with a hollow cavity, which will continuously accumulate and hinder the subsequent impulse discharge, thereby increasing the subsequent impulse grounding and the subsequent impulse voltage.

[0004] Therefore, in the actual process of multiple lightning discharges, if the traditional method is continued to be used to evaluate the impulse dissipation performance without considering the subsequent voltage rise caused by continuous impulse discharge, it will cause errors in the evaluation of the lightning dissipation performance of the grounding device and the evaluation results will be inaccurate.

[0005] In view of this, this application is hereby filed. Summary of the Invention

[0006] The technical problem to be solved by the present invention is that in the prior art, the subsequent voltage rise caused by continuous impulse discharge is not taken into account when evaluating the impulse dissipation performance, resulting in errors in the evaluation of the lightning impulse dissipation performance of the grounding device and inaccurate evaluation results. The purpose of the present invention is to provide a method, system and medium for evaluating the lightning impulse dissipation performance of a grounding device, which can reduce the errors in the evaluation of the lightning impulse dissipation performance of the grounding device and improve the accuracy of the evaluation results.

[0007] The present invention is achieved through the following technical solutions:

[0008] A method for evaluating the lightning impulse current dissipation performance of a grounding device, the method comprising the following steps:

[0009] Obtain environmental parameters and impulse grounding resistance of the grounding device;

[0010] Based on the environmental parameters and in combination with the time interval between lightning strikes, a subsequent strike coefficient is calculated;

[0011] Calculating a subsequent impulse resistance based on the subsequent impulse coefficient and the impulse grounding resistance;

[0012] The impulse grounding resistance and the subsequent impulse grounding resistance are respectively compared with a grounding resistance safety threshold, and the safety performance of the grounding device is predicted based on the comparison results.

[0013] Traditionally, when evaluating the lightning impulse dissipation performance of a grounding device, an impulse grounding resistance based on the equivalent of an impulse system is usually used as an evaluation indicator. However, when using this method to evaluate the grounding device, the subsequent voltage rise caused by continuous impulse discharge is not considered in the evaluation of the impulse dissipation performance, resulting in errors in the evaluation of the lightning impulse dissipation performance of the grounding device and inaccurate evaluation results. The present invention provides a method for evaluating the lightning impulse dissipation performance of a grounding device. By setting a subsequent impulse coefficient related to the number of lightning impulses and environmental factors, and simultaneously judging the lightning impulse dissipation performance safety of the grounding device through the subsequent impulse resistance calculated by the subsequent impulse coefficient and the grounding impulse resistance, the error in the lightning impulse dissipation performance evaluation of the grounding device can be reduced, and the accuracy of the evaluation results is improved.

[0014] Preferably, the method for obtaining the impulse grounding resistance is:

[0015] The impulse grounding resistance is obtained by obtaining an impact coefficient and a power frequency grounding resistance of the grounding device and performing a product operation on the impact coefficient and the power frequency grounding resistance.

[0016] Preferably, the environmental parameters include grounding electrode structure, soil resistivity and soil type moisture content.

[0017] Preferably, the specific expression of the subsequent impact coefficient is:

[0018]

[0019] α2=f(x i ) = f(P, x1, x2, ...)

[0020] α2 is the subsequent impact coefficient, b and c are the fitted environmental parameter constants, f(x i ) is a comprehensive representation function of multiple factors, x i is the influencing parameter of the i-th factor, and P is the probability of occurrence of the factor.

[0021] Preferably, the specific expression of the subsequent impact resistance is:

[0022] R2=α2×R1=α2α1×R0

[0023] R2 is the subsequent impulse resistance, α2 is the subsequent impulse coefficient, R0 is the power frequency grounding resistance, α1 is the impulse coefficient, R1 is the impulse grounding resistance, t is the real-time lightning stroke interval, and T0 is the continuous time interval of lightning impulses.

[0024] Preferably, the impulse grounding resistance and the subsequent impulse grounding resistance are respectively compared with the safety threshold, and the specific comparison and the corresponding prediction result expression are:

[0025] Impact performance

[0026] R s is the ground resistance safety threshold.

[0027] The present invention also provides a grounding device lightning impulse dispersion performance evaluation system, comprising a parameter acquisition module, a first calculation module, a second calculation module and a comparison and judgment module;

[0028] The parameter acquisition module is used to obtain environmental parameters and impulse grounding resistance of the grounding device;

[0029] The first calculation module is configured to calculate a subsequent impact coefficient based on the environmental parameters and a time interval between lightning impacts;

[0030] The second calculation module is configured to calculate a subsequent impulse resistance based on the subsequent impulse coefficient and the impulse grounding resistance;

[0031] The comparison and judgment module is used to compare the impulse grounding resistance and the subsequent impulse grounding resistance with the grounding resistance safety threshold respectively, and predict the safety performance of the grounding device based on the comparison results of the two.

[0032] Preferably, in the parameter acquisition module, the impulse grounding resistance is acquired by acquiring an impulse coefficient and a power frequency grounding resistance of the grounding device, and performing a product operation on the impulse coefficient and the power frequency grounding resistance to obtain the impulse grounding resistance.

[0033] Preferably, the environmental parameters include grounding electrode structure, soil resistivity, and soil type moisture content.

[0034] The present invention also provides a computer storage medium on which a computer program is stored. When the computer program is executed by a processor, the method described above is implemented.

[0035] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0036] Embodiments of the present invention provide a method, system, and medium for evaluating the lightning impulse dissipation performance of a grounding device. By setting a subsequent impulse coefficient related to the number of lightning impulses and environmental factors, and simultaneously judging the lightning impulse dissipation performance safety of the grounding device using the subsequent impulse resistance and ground impulse resistance calculated from the subsequent impulse coefficient, the method can reduce errors in evaluating the lightning impulse dissipation performance of the grounding device and improve the accuracy of the evaluation results. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without making any creative efforts.

[0038] Figure 1 Schematic diagram of the evaluation method;

[0039] Figure 2 This is a graph showing the ratio of the subsequent shock resistance to the first shock resistance changing with time interval. DETAILED DESCRIPTION

[0040] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with examples and drawings. The exemplary embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0041] In the following description, numerous specific details are set forth to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that these specific details are not necessarily required to practice the present invention. In other embodiments, well-known structures, circuits, materials, or methods are not described in detail to avoid obscuring the present invention.

[0042] Throughout this specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment of the present invention. Therefore, appearances of the phrases "one embodiment," "an embodiment," "an example," or "an example" in various places throughout this specification are not necessarily all referring to the same embodiment or example. Furthermore, the particular features, structures, or characteristics may be combined in one or more embodiments or examples in any suitable combinations and / or subcombinations. Furthermore, it will be understood by those of ordinary skill in the art that the figures provided herein are for illustrative purposes only and are not necessarily drawn to scale. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0043] In the description of the present invention, the terms "front", "back", "left", "right", "up", "down", "vertical", "horizontal", "high", "low", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the scope of protection of the present invention.

[0044] Example 1

[0045] Traditionally, the lightning surge dissipation performance of grounding systems is evaluated using the equivalent surge grounding resistance of the surge system as a metric. This resistance is calculated as the product of the power frequency grounding resistance and the surge coefficient, and is compared to the safety threshold of the grounding resistance. When the surge grounding resistance exceeds the safety threshold, the grounding design is deemed to have a safety issue; otherwise, the design is deemed to meet safety requirements. However, this method fails to consider the subsequent voltage rise caused by continuous surge discharges, leading to inaccurate evaluation results.

[0046] This embodiment discloses a method for evaluating the lightning impulse dispersion performance of a grounding device. By setting a subsequent impulse coefficient related to the number of lightning impulses and environmental factors, and simultaneously judging the lightning impulse dispersion performance safety of the grounding device through the subsequent impulse resistance calculated by the subsequent impulse coefficient and the grounding impulse resistance, the error in the lightning impulse dispersion performance evaluation of the grounding device can be reduced, and the accuracy of the evaluation results can be improved. The specific evaluation method in this embodiment is as follows: Figure 1 As shown, the method steps include:

[0047] S1: Obtain environmental parameters and impulse grounding resistance of the grounding device;

[0048] The method for obtaining the impulse grounding resistance is to obtain the impulse coefficient and power frequency grounding resistance of the grounding device, and then multiply the impulse coefficient and the power frequency grounding resistance to obtain the impulse grounding resistance. The environmental parameters include the grounding electrode structure, soil resistivity, soil type moisture content, etc.

[0049] In step S1, environmental parameters are set in the grounding device. After long-term operation, these parameters will have an impact on the grounding device. Therefore, in this embodiment, the impact of environmental factors on the grounding device during the long-term operation of the grounding device is considered, and relevant environmental factors are obtained for comprehensive calculation.

[0050] S2: Based on the environmental parameters and the time interval between lightning strikes, the subsequent impact coefficient is calculated. As a new supplementary evaluation parameter for soil impact current dissipation performance, the subsequent impact coefficient quantitatively characterizes the change in post-impact grounding resistance caused by continuous impacts, thereby reflecting the post-impact voltage rise. Furthermore, using the subsequent impact coefficient as a supplementary indicator fully aligns with existing assessment methods that calculate impact grounding resistance based on the impact coefficient, improving assessment accuracy while facilitating widespread adoption without losing consistency with common methods.

[0051] The post-impact coefficient increases exponentially with increasing time intervals when the intervals between successive impacts are short. Because the post-impact grounding resistance can be considered the first impact grounding resistance multiplied by the post-impact coefficient, when the time interval is short, the post-impact grounding resistance increases exponentially and approaches 1. When the time interval is long, the post-impact coefficient becomes greater than 1. Therefore, the post-impact coefficient is defined as a piecewise function, and its specific expression is:

[0052]

[0053] α2=f(x i )=f(P,x1,x2,…)

[0054] α2 is the subsequent impact coefficient, b and c are the fitted environmental parameter constants, f(x i ) is a comprehensive representation function of multiple factors, x i is the variable that affects the subsequent impact coefficient, P is the probability factor, t is the real-time lightning strike interval, and T0 is the continuous time interval of lightning impulses.

[0055] where x1~x i They represent the influence of three aspects: medium, current, grounding electrode, and multiple factors that are not studied in this paper. P represents the probabilistic factor: the change law of the subsequent impact coefficient. When the time interval is small, the subsequent impact coefficient increases exponentially with the increase of the time interval and is fixed. When the time interval is large, the subsequent impact coefficient is related to multiple influencing factors and is probabilistic. When the time interval exceeds a certain value, the subsequent impact coefficient is a probability function. The greater the subsequent voltage rise ratio, the smaller the probability of this situation, that is, there is a concept of the maximum subsequent impact coefficient. The specific rules are as follows. Figure 2 shown.

[0056] S3: Calculating a subsequent impulse resistance based on the subsequent impulse coefficient and the impulse grounding resistance;

[0057] The specific expression of the subsequent impact resistance is:

[0058] R2=α2×R1=α2α1×R0

[0059] R2 is the subsequent impulse resistance, α2 is the subsequent impulse coefficient, R0 is the power frequency grounding resistance, α1 is the impulse coefficient, and R1 is the impulse grounding resistance.

[0060] S4: Compare the impulse grounding resistance and the subsequent impulse grounding resistance with a grounding resistance safety threshold value respectively, and evaluate the safety performance of the grounding device based on the comparison results.

[0061] In step S4, the grounding device is evaluated for early warning by using a multi-stage composite index, with both the impact grounding resistance and the subsequent impact grounding resistance as evaluation indicators. At the same time, an early warning state is added, and a multi-stage evaluation standard is constructed to achieve the probabilistic and uncertain margin setting for the subsequent impact voltage transition rise.

[0062] The recursive process of the judgment conditions of each indicator is as follows: considering the impact of continuous impact on the impact grounding resistance, it is required that each impact grounding resistance under continuous impact is less than the safety threshold of grounding, that is, the first impact grounding resistance R1 and the subsequent impact grounding resistance R2 are both less than the safety threshold R in the standard. s , specifically:

[0063] R2<R s ,R1<R s / α2

[0064] Since the subsequent impact coefficient is affected by uncertainty factors such as the number of lightning strikes under the same factor, it is a range of values. Therefore, in order to ensure that the conclusion of the grounding safety assessment is more reliable, it is necessary to ensure that the subsequent impact coefficient takes a more stringent maximum value α. 2max When the subsequent impact grounding resistance is still less than the safety threshold, that is:

[0065] R 2max <R s ,R1<R s / α 2max

[0066] At the same time, in actual situations, due to changes in environmental conditions, for example, in a certain area, the moisture content and resistivity of the soil will change due to the alternation of seasons. The alternation of seasons will affect the changes in lightning parameters. Temperature and soil modification will also change soil parameters. Therefore, the subsequent impact coefficient α 2max It is not a definite value; the subsequent impact coefficient measured in different seasons and time periods may be different.

[0067] Therefore, we need to consider the most demanding working environment in the evaluation, that is, within the range of possible factor changes, consider the maximum subsequent impact coefficient α that may appear on the time scale under the influence of multiple factors.tmax , according to the current research definition α tmax =1.7. That is, during the grounding evaluation process, if R1.α 2max <R s , but 1.7R1>R s , it means that the grounding assessment is qualified in a short period of time, but safety problems may occur in long-term operation. The maximum value of the subsequent impact grounding resistance is R tmax =1.7R1.

[0068] The safety assessment limit is divided into multiple stages in the assessment method, and two safety gear limits R are set. Q and R H .make

[0069] R Q =R s / 1.7,R H =0.95R s

[0070] The specific judgment condition is that if R2>R H =0.95R s , it can be seen that the grounding resistance value in this area does not meet the safety grounding requirements, because no matter how many times lightning strikes the ground grid, the rise in ground potential may threaten the safety of people and electrical equipment. Therefore, the grounding safety does not meet the requirements or is unqualified at this time.

[0071] When R1>R Q =R S / 1.7 and R2<R H =0.95R S When , it can be determined that in this case, the grounding design meets the safety grounding requirements. However, if a more severe situation occurs at this time, that is, R tmax =1.7R1>R S , it means that the converter station may have a subsequent impact grounding resistance that does not meet the safety grounding requirements under strict conditions or during long-term operation.

[0072] Since the subsequent impulse lifting phenomenon does not occur 100%, when lightning dissipates through the grounding network, the subsequent impulse grounding resistance does not meet the safety grounding requirements. Therefore, the grounding is in a safety warning state at this time. The reason for choosing 0.95R S This is because in actual evaluation, a certain margin must be left for the evaluation results, and this margin can be set to different values according to actual conditions.

[0073] When R1<R Q =R SWhen the value is / 1.7, the subsequent impulse grounding resistance in the area also meets the safety grounding requirements. It can be determined that when multiple impulse lightning is dispersed by the grounding grid, the grounding resistance of each impulse is less than the safety threshold. Therefore, the grounding design is considered to meet the safety grounding conditions at this time.

[0074] In summary, the specific expression of grounding safety warning based on voltage rise is:

[0075] Impact performance

[0076] Specific implementation process:

[0077] Taking a vertical grounding electrode as an example, combined with parameters such as the tower voltage level, the regulations stipulate that the safety threshold for impulse grounding resistance at this time is 30Ω, i.e., RS = 30Ω, and the impulse coefficient α_1 = 1.2. Investigations revealed that the local soil moisture content is 6%, the salt content is 0.5%, and the soil is sandy, with a vertical grounding electrode. Experimental calculations show that α2max = 1.5 at this time. Based on these parameters, the grounding design is qualified when the power frequency grounding resistance is less than 14.58Ω. When the power frequency grounding resistance is greater than 14.58Ω and less than 15.83Ω, the grounding design enters a warning state. When the power frequency grounding resistance is greater than 15.83Ω, the grounding design fails.

[0078] The key parameters of ground impact characteristics in different situations are shown in Table 1.

[0079] In case 1, the actual power-frequency grounding resistance here is calculated using methods such as the Wenner quadrupole method to be 7Ω, or R0 = 7Ω. The calculated grounding resistance for the first impulse is 8.4Ω, and the grounding resistance for the subsequent impulse is 12.6Ω. The grounding resistance for the first impulse is less than 30 / 1.7 = 17.5Ω, and the grounding resistance for the subsequent impulse is less than 30 × 0.95 = 28.5Ω. Therefore, the grounding grid is deemed to meet safety grounding standards and pass the test.

[0080] If the on-site measurement result is situation 2, it is unqualified; if the on-site measurement result is situation 3, it is a warning.

[0081] Table 1 Case analysis of continuous impact assessment

[0082]

[0083]

[0084] This embodiment discloses a method for evaluating the lightning impulse dissipation performance of a grounding device. By setting a subsequent impulse coefficient related to the number of lightning impulses and environmental factors, and simultaneously judging the lightning impulse dissipation performance safety of the grounding device using the subsequent impulse resistance and the ground impulse resistance calculated using the subsequent impulse coefficient, the method can reduce errors in the lightning impulse dissipation performance evaluation of the grounding device and improve the accuracy of the evaluation results.

[0085] Example 2

[0086] This embodiment discloses a system for evaluating the lightning impulse dissipation performance of a grounding device. This embodiment is intended to implement an evaluation method as in the first embodiment, and includes a parameter acquisition module, a first calculation module, a second calculation module, and a comparison and judgment module.

[0087] The parameter acquisition module is used to obtain environmental parameters and impulse grounding resistance of the grounding device;

[0088] The first calculation module is configured to calculate a subsequent impact coefficient based on the environmental parameters and a time interval between lightning impacts;

[0089] The second calculation module is configured to calculate a subsequent impulse resistance based on the subsequent impulse coefficient and the impulse grounding resistance;

[0090] The comparison and judgment module is used to compare the impulse grounding resistance and the subsequent impulse grounding resistance with the grounding resistance safety threshold respectively, and evaluate the safety performance of the grounding device based on the comparison results of the two.

[0091] In the parameter acquisition module, the impulse grounding resistance is acquired by acquiring an impulse coefficient and a power frequency grounding resistance of the grounding device, and performing a product operation on the impulse coefficient and the power frequency grounding resistance to obtain the impulse grounding resistance.

[0092] The environmental parameters include grounding electrode structure, soil resistivity, and soil type and moisture content.

[0093] Example 3

[0094] This embodiment discloses a computer storage medium on which a computer program is stored. When the computer program is executed by a processor, the method described in the first embodiment is implemented.

[0095] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0096] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by issuing instructions from a computer program. These computer programs can be provided to issue instructions to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the issued instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0097] These computer program issuing instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the issuing instructions stored in the computer readable memory produce a manufactured product including an issuing instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0098] These computer program instructions may also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, whereby the instructions executed on the computer or other programmable device provide a means for implementing the process described in the flow chart. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0099] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for evaluating the lightning impulse dissipation performance of a grounding device, characterized in that: The method steps include: Obtain environmental parameters and impulse grounding resistance of the grounding device; Based on the environmental parameters and in combination with the time interval between lightning strikes, a subsequent strike coefficient is calculated; Calculating a subsequent impulse grounding resistance based on the subsequent impulse coefficient and the impulse grounding resistance; comparing the impulse grounding resistance and the subsequent impulse grounding resistance with a grounding resistance safety threshold, respectively, and evaluating the safety performance of the grounding device based on the comparison results; The method for obtaining the impulse grounding resistance is as follows: obtaining the impulse coefficient and the power frequency grounding resistance of the grounding device, and performing a product operation on the impulse coefficient and the power frequency grounding resistance to obtain the impulse grounding resistance; The environmental parameters include grounding electrode structure and soil resistivity and soil type moisture content; The specific expression of the subsequent impact coefficient is: α2 is the subsequent impact coefficient, b and c are the fitted environmental parameter constants, f(x i ) is a comprehensive representation function of multiple factors, x i is the influencing parameter of the i-th factor, P is the probability factor, t is the real-time lightning strike interval, and T0 is the continuous time interval of lightning impulses; The specific expression of the subsequent impulse grounding resistance is: R2=α2×R1=α2α1×R0 R2 is the subsequent impact grounding resistance, α2 is the subsequent impact coefficient, R0 is the power frequency grounding resistance, α1 is the impact coefficient, and R1 is the impact grounding resistance; The impulse grounding resistance and the subsequent impulse grounding resistance are compared with the safety threshold respectively. The specific comparison and the corresponding prediction result expression are as follows: R s is the ground resistance safety threshold.

2. A grounding device lightning impulse dissipation performance evaluation system, characterized in that: Used to implement the evaluation method according to claim 1, comprising a parameter acquisition module, a first calculation module, a second calculation module and a comparison and judgment module; The parameter acquisition module is used to obtain environmental parameters and impulse grounding resistance of the grounding device; the first calculation module is used to calculate the subsequent impulse coefficient based on the environmental parameters and the time interval of the lightning impulse; The second calculation module is configured to calculate a subsequent impulse grounding resistance based on the subsequent impulse coefficient and the impulse grounding resistance; The comparison and judgment module is used to compare the impulse grounding resistance and the subsequent impulse grounding resistance with the grounding resistance safety threshold respectively, and evaluate the safety performance of the grounding device based on the comparison results of the two.

3. A grounding device lightning impulse dissipation performance evaluation system according to claim 2, characterized in that: In the parameter acquisition module, the impulse grounding resistance is acquired by acquiring an impulse coefficient and a power frequency grounding resistance of the grounding device, and performing a product operation on the impulse coefficient and the power frequency grounding resistance to obtain the impulse grounding resistance.

4. A grounding device lightning impulse dissipation performance evaluation system according to claim 2, characterized in that: The environmental parameters include grounding electrode structure, soil resistivity, and soil type and moisture content.

5. A computer storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the evaluation method according to claim 1 is implemented.

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