Intelligent grounding wire grounding resistance monitoring method

Abstract

The invention discloses an intelligent grounding wire grounding resistance monitoring method. The method comprises the steps that the air temperature and the air humidity of the whole point of future preset days are acquired; converting to obtain a soil temperature estimated value and a soil humidity estimated value; respectively inputting the soil temperature estimated value and the soil humidity estimated value into a soil resistivity estimation model and a corrosion product resistivity estimation model to obtain a soil resistivity estimated value and a corrosion product resistivity estimated value; inputting the estimated value of the soil resistivity, the inclination angle of the grounding nail, the depth of the grounding nail inserted into the soil and the diameter of the grounding nail into a model of the soil diffusion resistance R1 to obtain an estimated value of the soil diffusion resistance; inputting the effective radius, the initial radius and the corrosion product resistivity estimated value into a corrosion product resistance R2 model to obtain a corrosion product resistance estimated value; and adding the corrosion product resistance estimated value and the soil diffusion resistance estimated value as a grounding resistance estimated value to obtain the grounding resistance estimated value.

Description

Technical Field

[0001] The present invention relates to the technical field of ground wire monitoring, and particularly to an intelligent ground wire grounding resistance monitoring method. Background Art

[0002] The magnitude of the grounding resistance directly affects the effectiveness of the grounding system. When the grounding resistance increases, it may lead to the failure of the grounding system and increase the risk of electric shock. By monitoring the grounding resistance, the effectiveness of the grounding system can be ensured, thereby reducing the risk of electric shock. Existing portable protective ground wires cannot regularly monitor the change of the grounding resistance during long-term use as a protective ground. Even though there are some intelligent ground wires that can monitor the grounding resistance in real time, they cannot predict the grounding resistance, resulting in the inability to predict in advance when the grounding resistance is slowly increasing due to environmental factors and other reasons, and unable to take measures in advance to solve potential electrical accidents. Therefore, real-time monitoring and prediction of the change of the grounding resistance are of great significance for ensuring the safety, stability, and reliability of the grounding system. Summary of the Invention

[0003] The purpose of the present invention is to provide an intelligent ground wire grounding resistance monitoring method to solve the technical problems that existing intelligent ground wires cannot accurately predict the grounding resistance and cannot take measures in advance to address risks.

[0004] On the one hand, the present invention provides an intelligent ground wire grounding resistance monitoring method, including the following steps:

[0005] Call the weather forecast API to obtain the hourly air temperature and air humidity for the next preset number of days;

[0006] Convert the air temperature and air humidity into estimated soil temperature and estimated soil humidity for a certain hour of a certain day in the future;

[0007] Input the estimated soil temperature and the estimated soil humidity into the soil resistivity estimation model and the corrosion product resistivity estimation model respectively to obtain the estimated soil resistivity values and the estimated corrosion product resistivity values for all hours of each day in the next preset number of days;

[0008] Obtain the current inclination angle of the grounding nail, the insertion depth of the grounding nail into the soil, and the diameter of the grounding nail, and input the estimated soil resistivity value, the inclination angle of the grounding nail, the insertion depth of the grounding nail into the soil, and the diameter of the grounding nail into the model of the soil spreading resistance R1 to obtain the estimated soil spreading resistance values for all hours of each day in the preset number of days;

[0009] Obtain the effective radius of the remaining metal part of the grounding nail after corrosion and the initial radius of the grounding nail, and input the effective radius, the initial radius, and the estimated corrosion product resistivity value into the model of the corrosion product resistance R2 to obtain the estimated corrosion product resistance values for all hours of each day in the preset number of days;

[0010] Add the estimated value of the corrosion product resistance and the estimated value of the soil dissipation resistance as the estimated value of the grounding resistance, and obtain the estimated value of the grounding resistance at all whole points for the preset number of days.

[0011] In some embodiments, the present invention further includes:

[0012] Compare the estimated value of the grounding resistance with the grounding resistance threshold. If it is greater than the threshold, mark this time point as an abnormal time point;

[0013] Obtain the actual value of the current grounding resistance, analyze the reasons for the abnormal grounding resistance, and obtain the abnormal items. The actual value of the grounding resistance is the resistance value of the conductive line part formed by the grounding nail inserted into the soil, the soil, and the probe in series.

[0014] In some embodiments, the analysis of the reasons for the abnormal grounding resistance specifically includes:

[0015] Compare the actual value of the current grounding resistance with the grounding resistance threshold. If it is higher than the grounding resistance threshold, perform the analysis of abnormal items according to the set priority order of influence item analysis to obtain the abnormal items. The influence items include the estimated value of soil resistivity, the estimated value of corrosion product resistivity, the inclination angle of the grounding nail, the effective radius, and the depth of the grounding nail inserted into the soil, and a reference value is set for each influence item:

[0016] If the actual value of the current grounding resistance is lower than the grounding resistance threshold, input the estimated value of the corrosion product resistivity into the grounding resistance prediction formula for all risk time points according to its reference value, and do not adjust other influence items to obtain the corrected value of the grounding resistance for all risk time points. If the corrected values are all less than the grounding resistance threshold, the estimated value of the corrosion product resistivity is the abnormal item. If there are still corrected values higher than the grounding resistance threshold, input the estimated value of the soil resistivity into the grounding resistance prediction formula for all risk time points according to its reference value, and do not adjust other influence items to obtain the corrected value of the grounding resistance for all risk time points. If the corrected values are all less than the grounding resistance threshold, the estimated value of the soil resistivity is the abnormal item. If there are still corrected values higher than the grounding resistance threshold, the estimated values of the soil resistivity and the corrosion product resistivity are the abnormal items. The grounding resistance prediction formula is R = R1 + R2.

[0017] In some embodiments, perform the analysis of abnormal items according to the set priority order of influence item analysis to obtain the abnormal items, specifically:

[0018] Input the influence item with the highest priority into the grounding resistance prediction formula for the current and risk time points according to its reference value, and do not adjust other influence items to obtain the corrected value of the grounding resistance for the current and risk time points. If the corrected values are all less than the grounding resistance threshold, do not continue the analysis, and the influence item with the highest priority is the abnormal item;

[0019] If there are still correction values higher than the grounding resistance threshold, continue the analysis. Input the next priority influencing item and all the influencing items analyzed traversally into the grounding resistance prediction formula at the current and risk time points according to their respective set values, without adjusting other influencing items, to obtain the grounding resistance correction values at the current and risk time points. If the correction values are all less than the grounding resistance threshold, the current priority and all the influencing items analyzed traversally are abnormal items;

[0020] If there are still correction values higher than the grounding resistance threshold, repeat the above idea of continuing the analysis to obtain abnormal items.

[0021] In some embodiments, the present invention further includes:

[0022] Confirm the abnormal items that need to be adjusted, and adjust the influencing items according to the reference values, specifically: preset a measurement error range for each influencing item. If there are no less than two obtained abnormal items, judge whether the difference range between the abnormal item and its reference value is within the deviation range. If it exceeds, take the abnormal item as an adjustment item. If none of the abnormal items exceed the deviation range, take all the abnormal items with a non-zero difference from the reference value as adjustment items.

[0023] In some embodiments, the present invention further includes:

[0024] Calculate the priority index of the influencing item according to the sensitivity of the influencing item to the grounding resistance R and the adjustment convenience of the influencing item: Where X i is the i-th influencing item, S i is the adjustment convenience of the i-th influencing item, and the value range is between 0 and 1, which is selected by mapping according to the preset storage mapping table, represents the input sensitivity of the i-th influencing item to the resistance R, is to normalize the derivative, k1 and k2 are compensation coefficients, and the value range is between 0 and 1, and the sum of k1 and k2 is 1;

[0025] Obtain the priority index of all influencing items at the first risk time point, and set the analysis priority of the influencing items in order according to the level of the priority index.

[0026] In some embodiments, the soil resistivity estimation model is:

[0027]

[0028] Among them, ρ0 is the reference resistivity (at temperature T0 and humidity H0), α is the temperature coefficient (usually negative, and the resistivity decreases with the increase of temperature), β is the humidity index (the resistivity decreases with the increase of humidity), Hsoil is the current soil humidity, and Tsoil is the current soil temperature.

[0029] In some embodiments, the corrosion product resistivity estimation model is as follows:

[0030]

[0031] where ρ z is the resistivity of the corrosion product at the reference temperature T Z and the reference humidity H Z , α Z and β Z are the coefficients of the influence of temperature and humidity on the resistivity respectively, obtained by fitting experimental data. Generally, α < 0 and β < 0. T is the actual temperature and H is the actual humidity.

[0032] In some embodiments, the formula for the soil spreading resistance R1 is specifically:

[0033]

[0034] where ρ soil is the soil resistivity, L is the burial depth of the grounding nail, d is the diameter of the grounding nail, and θ is the inclination angle of the grounding nail.

[0035] In some embodiments, the formula for the corrosion product resistance R2 is specifically: where ρ corr is the resistivity of the corrosion product, θ is the inclination angle of the grounding nail, r 0 is the initial radius of the grounding nail, r c is the effective radius of the remaining metal part after corrosion, and the parameter χ can be determined by experiments and is usually between 0 and 1.

[0036] The beneficial effects of the present invention are as follows:

[0037] On the basis of realizing real-time monitoring, the present invention can also estimate the change of the grounding resistance in a certain number of future days, so as to identify risks in advance and take measures against risks in advance, improving the safety, stability and reliability of the grounding system. The grounding resistance prediction formula adopted by the present invention takes into account both the corrosion product resistance and the soil spreading resistance, and combines the influence of environmental factors, the inclination angle of the grounding nail and the corrosion condition of the grounding nail on the grounding resistance, improving the accuracy of grounding resistance prediction;

[0038] If there is an abnormality in the predicted change of the grounding resistance, it is possible to analyze the cause of the grounding resistance abnormality. During the analysis, according to the comparison result of the actual value of the grounding resistance and the grounding resistance threshold, different strategies for analyzing the cause of the abnormality are adopted, which helps to improve the analysis efficiency;

[0039] According to the sensitivity of the influencing items to the grounding resistance R and the convenience of adjusting the influencing items, the analysis priority of the influencing items is set, so that the influencing items that mainly contribute to the increase of the grounding resistance and are relatively convenient to adjust can be quickly found. Brief Description of the Drawings

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0041] Figure 1 It is a flowchart of the intelligent grounding wire grounding resistance monitoring method provided by an embodiment of the present invention; Detailed Embodiments

[0042] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0043] Please refer to Figure 1 , an embodiment of the present invention provides an intelligent grounding wire grounding resistance monitoring method, including the following steps:

[0044] S1. Call the weather forecast API to obtain the hourly air temperature and air humidity for the next preset number of days;

[0045] The present invention can monitor and obtain the grounding resistance value in real time. The specific implementation method can be voltage division to measure the resistance. A voltage dividing resistor (with a known resistance value), a grounding nail inserted into the soil, and the soil and the probe form a circuit. Apply a power supply to this circuit, and according to the voltage division formula, calculate and obtain the resistance value of the circuit formed by the grounding nail inserted into the soil, the soil, and the probe, that is, obtain the grounding resistance value.

[0046] On the basis of real-time monitoring, the present invention can also perform grounding resistance prediction. It can be to regularly initiate the grounding resistance prediction for the next preset number of days, or to initiate the prediction process according to the received prediction instruction.

[0047] When starting the grounding resistance prediction process, first call the weather forecast API to obtain the hourly air temperature and air humidity for the next preset number of days. Currently, there are many weather APIs that support providing the hourly temperature and humidity forecast data for the next few days, and any one can be selected for use.

[0048] S2. Convert the air temperature and air humidity into predicted values of soil temperature and soil humidity at a certain hour on a certain day in the future.

[0049] The present invention uses a deep Q-learning model for soil temperature and humidity prediction. This model is based on a weighted combination of long short-term memory (LSTM), gated recurrent unit (GRU), and bi-directional long short-term memory (Bi-LSTM) as basic models to form a DQN-L-G-B combined prediction model. This model can effectively complete the accurate prediction of soil moisture and temperature based on the near-surface air temperature and humidity of the soil.

[0050] Input the hourly air temperature and air humidity for a preset number of days into the deep Q-learning model to obtain predicted values of soil temperature and soil humidity at a certain hour on a certain day in the future.

[0051] S3. Input the predicted values of soil temperature and soil humidity into a soil resistivity estimation model and a corrosion product resistivity estimation model respectively to obtain the estimated values of soil resistivity and corrosion product resistivity at all hourly points for each day in the future preset number of days.

[0052] In the embodiment of the present invention, the soil resistivity and the corrosion product resistivity are estimated based on the predicted values of soil temperature and soil humidity. The soil resistivity estimation model is:

[0053]

[0054] where ρ 0 is the reference resistivity (at temperature T0 and humidity H0), α is the temperature coefficient (usually negative, resistivity decreases with increasing temperature), β is the humidity index (resistivity decreases with increasing humidity), H soil is the current soil humidity, and T soil is the current soil temperature.

[0055] The corrosion product resistivity estimation model is:

[0056]

[0057] where ρ z is the corrosion product resistivity at the reference temperature T Z and the reference humidity H Z , α Z and β ZThey are the coefficients of the influence of temperature and humidity on resistivity, respectively, obtained by fitting experimental data.

[0058] Generally, α < 0, β < 0, T is the actual temperature, and H is the actual humidity.

[0059] S4. Obtain the current inclination angle of the grounding nail, the insertion depth of the grounding nail into the soil, and the diameter of the grounding nail. Input the estimated value of soil resistivity, the inclination angle of the grounding nail, the insertion depth of the grounding nail into the soil, and the diameter of the grounding nail into the model of the soil spreading resistance R1 to obtain the estimated values of the soil spreading resistance at all whole points of each day within the preset number of days.

[0060] It can be to obtain the inclination angle of the grounding nail through a gyroscope and measure the insertion depth of the grounding nail with a rangefinder. The diameter of the grounding nail is a pre-stored parameter. The soil spreading resistance of the present invention not only considers the influence of temperature and humidity on the grounding resistance, but also considers the influence of the inclination angle of the grounding nail on the grounding resistance, improving the accuracy of grounding resistance prediction.

[0061] The formula for the soil spreading resistance R1 is specifically:

[0062]

[0063] Among them, ρ soil is the soil resistivity, L is the burial depth of the grounding nail, d is the diameter of the grounding nail, and θ is the inclination angle of the grounding nail.

[0064] S5. Obtain the effective radius of the remaining metal part of the grounding nail after corrosion and the initial radius of the grounding nail. Input the effective radius, the initial radius, and the estimated value of the resistivity of the corrosion product into the model of the corrosion product resistance R2 to obtain the estimated values of the corrosion product resistance at all whole points of each day within the preset number of days.

[0065] Specific implementation can be to measure the effective radius of the grounding nail using an ultrasonic thickness gauge. Through the corrosion product resistance R2 in the embodiment of the present invention, the part of the corrosion product resistance that increases the grounding resistance after the grounding nail is corroded can be obtained.

[0066] The formula for the corrosion product resistance R2 is specifically:

[0067] Among them, ρ corr is the resistivity of the corrosion product, θ is the inclination angle of the grounding nail, r 0 is the initial radius of the grounding nail, and r c is the effective radius of the remaining metal part after corrosion.

[0068] S6. Add the estimated value of the corrosion product resistance and the estimated value of the soil spreading resistance as the estimated value of the grounding resistance to obtain the estimated values of the grounding resistance at all whole points within the preset number of days.

[0069] On the basis of realizing real-time monitoring, the present invention can also estimate the change of the grounding resistance in a certain number of days in the future, so as to identify risks in advance, take measures against risks in advance, and improve the safety, stability and reliability of the grounding system. The grounding resistance estimation formula in the embodiment of the present invention takes into account both the resistance of the corrosion product and the soil current dissipation resistance, and combines the influence of environmental factors, the inclination angle of the grounding nail and the corrosion condition of the grounding nail on the grounding resistance, so as to improve the accuracy of grounding resistance estimation.

[0070] During the use of the present invention, the grounding resistance formula can be periodically fine-tuned by comparing the actual value of the grounding resistance obtained through real-time monitoring with the estimated value calculated by the grounding resistance formula, so that the estimated value is closer to the actual value.

[0071] In some embodiments, the present invention further includes:

[0072] S7. Compare the estimated value of the grounding resistance with the grounding resistance threshold. If it is greater than the threshold, mark this time point as an abnormal time point;

[0073] S8. Obtain the actual value of the current grounding resistance, analyze the cause of the grounding resistance abnormality, and obtain the abnormal item. The actual value of the grounding resistance is the resistance value of the conductive line part formed by the series connection of the grounding nail inserted into the soil, the soil and the probe.

[0074] In order to ensure the safety of the grounding system, the size of the grounding resistance should be controlled within a certain safe value range. Set a grounding resistance threshold. If the estimated value of the grounding resistance at a certain time point is higher than the threshold, it is regarded as a risk, and the corresponding time point is an abnormal time point.

[0075] If there is an abnormal time point, analyze the cause of the grounding resistance abnormality to obtain the abnormal item. When analyzing, first obtain the actual value of the current grounding resistance, and adopt different abnormal cause analysis strategies according to the comparison result of the actual value of the grounding resistance and the grounding resistance threshold.

[0076] In some embodiments, the analysis of the cause of the grounding resistance abnormality specifically includes:

[0077] S71. Compare the actual value of the current grounding resistance with the grounding resistance threshold. If it is higher than the grounding resistance threshold, perform abnormal item analysis according to the set priority order of the influence item analysis, and obtain the abnormal item. The influence items include the estimated value of the soil resistivity, the estimated value of the corrosion product resistivity, the inclination angle of the grounding nail, the effective radius, and the depth of the grounding nail inserted into the soil, and a reference value is set for each influence item:

[0078] S72. If the actual value of the current grounding resistance is lower than the grounding resistance threshold, the estimated resistivity of the corrosion product is input into the grounding resistance prediction formula for all risk time points according to its reference value, and other influencing items are not adjusted to obtain the corrected values of the grounding resistance for all risk time points. If the corrected values are all less than the grounding resistance threshold, the estimated resistivity of the corrosion product is an abnormal item. If there are still corrected values higher than the grounding resistance threshold, the estimated soil resistivity is input into the grounding resistance prediction formula for all risk time points according to its reference value, and other influencing items are not adjusted to obtain the corrected values of the grounding resistance for all risk time points. If the corrected values are all less than the grounding resistance threshold, the estimated soil resistivity is an abnormal item. If there are still corrected values higher than the grounding resistance threshold, the estimated soil resistivity and the estimated resistivity of the corrosion product are abnormal items. The grounding resistance prediction formula is R = R1 + R2.

[0079] The specific steps for determining the analysis priority of influencing items are as follows:

[0080] According to the sensitivity of the influencing item to the grounding resistance R and the adjustment convenience of the influencing item, calculate the priority index of the influencing item: Where X i is the i-th influencing item, and S i is the adjustment convenience of the i-th influencing item, and its value range is between 0 and 1, which is selected by mapping according to the preset storage mapping table. represents the input sensitivity of the i-th influencing item to the resistance R. is to normalize the derivative, and k1 and k2 are compensation coefficients, and their value ranges are between 0 and 1, and the sum of k1 and k2 is 1;

[0081] Obtain the priority index of all influencing items at the first risk time point, and set the analysis priority of the influencing items in order according to the level of the priority index.

[0082] In some embodiments, according to the set order of the analysis priority of the influencing items, perform abnormal item analysis to obtain abnormal items. Specifically:

[0083] Input the influencing item with the highest priority into the grounding resistance prediction formula for the current and risk time points according to its reference value, and do not adjust other influencing items to obtain the corrected values of the grounding resistance for the current and risk time points. If the corrected values are all less than the grounding resistance threshold, do not continue the analysis, and the influencing item with the highest priority is the abnormal item;

[0084] If there are still correction values higher than the grounding resistance threshold, continue the analysis. Input the next priority influencing item and all the influencing items analyzed traversally into the grounding resistance prediction formula at the current and risk time points according to their respective set values, without adjusting other influencing items, to obtain the grounding resistance correction values at the current and risk time points. If the correction values are all less than the grounding resistance threshold, the current priority and all the influencing items analyzed traversally are abnormal items.

[0085] If there are still correction values higher than the grounding resistance threshold, repeat the above idea of continuing the analysis to obtain abnormal items.

[0086] If the actual value of the current grounding resistance is lower than the grounding resistance threshold, considering that the abnormal reason is mostly due to the change of environmental factors resulting in the increase of the grounding resistance, focus on analyzing whether the increase of the grounding resistance is caused by the increase of the resistivity of corrosion products or the increase of the soil resistivity. If the actual value of the current grounding resistance is also higher than the grounding resistance threshold, the abnormal item analysis will be carried out for all influencing items according to the set analysis priority. By confirming the abnormal items through the set analysis priority of the influencing items, the influencing items that mainly contribute to the increase of the grounding resistance and are relatively convenient to adjust can be quickly found.

[0087] In some embodiments, the present invention further includes: confirming the abnormal items that need to be adjusted, and adjusting the influencing items according to the reference value. Specifically: preset a measurement error range for each influencing item. If there are no less than two obtained abnormal items, judge whether the difference range between the abnormal item and its reference value is within the deviation range. If it exceeds, take the abnormal item as the adjustment item. If none of the abnormal items exceed the deviation range, take all the abnormal items with a non-zero difference from the reference value as the adjustment items.

[0088] The above has introduced in detail a method for monitoring the grounding resistance of an intelligent grounding wire provided by the present invention. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and modifications can still be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0089] Each embodiment in this application is described in a progressive manner. The same or similar parts among the embodiments can be referred to each other, and the key points of each embodiment are to illustrate the differences from other embodiments. In particular, for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment.

Claims

1. A method for monitoring grounding resistance of an intelligent grounding wire, characterized in that: The steps include: Call the weather forecast API to obtain the air temperature and humidity at the hour of the preset days in the future; Convert the air temperature and air humidity into an estimated soil temperature and soil humidity corresponding to a certain hour on a certain day in the future; Inputting the estimated soil temperature and the estimated soil moisture into a soil resistivity estimation model and a corrosion product resistivity estimation model respectively, to obtain estimated soil resistivity and corrosion product resistivity at all hourly points of each day in the future preset days; The current grounding nail inclination angle, the grounding nail insertion depth, and the grounding nail diameter are obtained, and the soil resistivity estimation value, the grounding nail inclination angle, the grounding nail insertion depth, and the grounding nail diameter are input into the soil stray resistance R1 model to obtain the estimated soil stray resistance values ​​at all hourly points of each day in the preset days. Obtain the effective radius of the remaining metal part after the current grounding nail is corroded and the initial radius of the grounding nail, input the effective radius, the initial radius, and the estimated value of the corrosion product resistivity into the model of the corrosion product resistance R2, and obtain the estimated value of the corrosion product resistance at all hour points of each day in the preset number of days; The estimated value of the corrosion product resistance and the estimated value of the soil scattered resistance are added as the estimated value of the grounding resistance, and the estimated value of the grounding resistance at all hourly points on the preset days is obtained.

2. The intelligent grounding wire grounding resistance monitoring method according to claim 1 is characterized in that: Also includes: Compare the estimated ground resistance value with the ground resistance threshold, and if the value is greater than the threshold, mark the time point as an abnormal time point; The actual value of the current grounding resistance is obtained, the cause of the abnormal grounding resistance is analyzed, and the abnormal item is obtained. The actual value of the grounding resistance is the resistance value of the conductive line formed in series by the grounding nail inserted into the soil, the soil and the probe.

3. The intelligent grounding wire grounding resistance monitoring method according to claim 2 is characterized in that: The analysis of the cause of abnormal ground resistance specifically includes: Compare the current actual grounding resistance value with the grounding resistance threshold. If it is higher than the grounding resistance threshold, perform abnormal item analysis according to the set priority order of the impact item analysis to obtain the abnormal items. The impact items include the estimated soil resistivity, the estimated corrosion product resistivity, the grounding nail inclination angle, the effective radius, and the depth of the grounding nail inserted into the soil. Set a benchmark value for each impact item: If the current actual value of grounding resistance is lower than the grounding resistance threshold, the estimated value of corrosion product resistivity is input into the grounding resistance estimation formula for all risk time points according to its benchmark value, and other influencing items are not adjusted to obtain the corrected value of grounding resistance for all risk time points. If the corrected values ​​are all less than the grounding resistance threshold, the estimated value of corrosion product resistivity is an abnormal item. If there are still corrected values ​​higher than the grounding resistance threshold, the estimated value of soil resistivity is input into the grounding resistance estimation formula for all risk time points according to its benchmark value, and other influencing items are not adjusted to obtain the corrected value of grounding resistance for all risk time points. If the corrected values ​​are all less than the grounding resistance threshold, the estimated value of soil resistivity is an abnormal item. If there are still corrected values ​​higher than the grounding resistance threshold, the estimated value of soil resistivity and the estimated value of corrosion product resistivity are abnormal items. The grounding resistance estimation formula is R=R1+R2.

4. The intelligent grounding wire grounding resistance monitoring method according to claim 3 is characterized in that: According to the set priority order of impact item analysis, abnormal item analysis is performed to obtain abnormal items, specifically: The highest priority influencing item is input into the ground resistance estimation formula at the current and risk time points according to its benchmark value. Other influencing items are not adjusted to obtain the ground resistance correction value at the current and risk time points. If the correction value is less than the ground resistance threshold, the analysis is discontinued and the highest priority influencing item is regarded as an abnormal item. If there are still correction values ​​higher than the grounding resistance threshold, continue the analysis, input the next priority influencing item and all the influencing items that have been traversed and analyzed into the grounding resistance estimation formula at the current and risk time points according to their respective set values, and do not adjust other influencing items to obtain the grounding resistance correction value at the current and risk time points. If the correction values ​​are all less than the grounding resistance threshold, the current priority and all the influencing items that have been traversed and analyzed are abnormal items; If there is still a correction value higher than the ground resistance threshold, repeat the above analysis to obtain the abnormal item.

5. The intelligent grounding wire grounding resistance monitoring method according to any one of claims 2 to 4, characterized in that: Also includes: Confirm the abnormal items that need to be adjusted, and adjust the influencing items according to the benchmark values. Specifically, preset a measurement error range for each influencing item. If there are no less than two abnormal items, determine whether the difference between the abnormal item and its benchmark value is within the deviation range. If it exceeds, the abnormal item will be used as an adjustment item. If all abnormal items do not exceed the deviation range, all abnormal items whose difference with the benchmark value is not 0 will be used as adjustment items.

6. The method for monitoring grounding resistance of an intelligent grounding wire according to claim 3, characterized in that: Also includes: According to the sensitivity of the influencing item to the grounding resistance R and the convenience of adjusting the influencing item, the priority index of the influencing item is calculated: Where X i is the i-th influencing term, S i is the adjustment convenience of the i-th influencing item, with a value range between 0 and 1, and is selected according to the mapping table stored in the preset. It represents the input sensitivity of the i-th influencing item to the resistor R, The derivative is normalized, k1 and k2 are compensation coefficients, ranging from 0 to 1, and the sum of k1 and k2 is 1; Obtain the priority index of all influencing items at the first risk time point, and set the analysis priority of the influencing items in order of priority index.

7. The intelligent grounding wire grounding resistance monitoring method according to claim 1 is characterized in that: The soil resistivity estimation model is: Where ρ0 is the reference resistivity (at temperature T0 and humidity H0), α is the temperature coefficient (usually negative, with increasing temperature causing resistivity to decrease), β is the humidity index (increasing humidity reduces resistivity), Hsoil is the current soil moisture, and Tsoil is the current soil temperature.

8. The method for monitoring grounding resistance of an intelligent grounding wire according to claim 1, characterized in that: The corrosion product resistivity estimation model is: Among them, ρ z At the reference temperature T Z and reference humidity H Z The resistivity of the corrosion products under Z and β Z They are the coefficients of the influence of temperature and humidity on resistivity, which are obtained by fitting experimental data. Generally, α<0, β<0, T is the actual temperature, and H is the actual humidity.

9. The method for monitoring grounding resistance of an intelligent grounding wire according to claim 1, characterized in that: The specific formula of soil stray resistance R1 is: Among them, ρ soil is the soil resistivity, L is the buried depth of the grounding nail, d is the diameter of the grounding nail, and θ is the inclination angle of the grounding nail.

10. The method for monitoring grounding resistance of an intelligent grounding wire according to claim 1, characterized in that: The specific formula for the corrosion product resistance R2 is: Among them, ρ corr is the resistivity of the corrosion product, θ is the inclination angle of the grounding nail, r0 is the initial radius of the grounding nail, and r c is the effective radius of the remaining metal part after corrosion. The parameter χ can be determined experimentally and is usually between 0 and 1.

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