A distribution network grounding construction process resistance standard automatic determination method

Abstract

The application provides a network grounding construction process resistance standard automatic determination method, comprising: deploying moisture content sensing sheet and depth position code disc in the grounding construction resistance determination system, collecting initial measurement, retest reading, sampling position label and construction date of grounding resistance and moisture content, forming original data set; verifying the preset effective drainage area boundary according to the sampling position label, identifying the soil layer part where the sampling point is located, obtaining the effective sampling sub-group; triggering seasonal check according to the wet resistance contradiction label, reading the last rainfall interval and freeze-thaw state in the seasonal working condition record corresponding to the construction date, calibrating the resistance standard determination caliber, forming the seasonal evaluation conclusion; excluding the sampling records outside the drainage area with surface layer humidification misjudgment conclusion, collecting the grounding resistance and moisture content paired reading bound by the sampling position label in the effective drainage area, and generating the determination data set.

Description

Technical Field

[0001] This invention relates to the field of information technology, and in particular to an automatic method for determining whether the resistance of a distribution network grounding system meets the required standards during construction. Background Technology

[0002] Grounding construction in power system distribution networks is a fundamental step in ensuring the safe operation of the power grid. The core function of grounding devices is to rapidly discharge current into the earth during faults or lightning strikes, thereby protecting equipment and personnel. The magnitude of grounding resistance directly determines the current dissipation effect and is a key indicator for evaluating construction quality. In practical engineering, the conductivity of soil is greatly affected by soil moisture.

[0003] When assessing the current dissipation capacity of grounding devices at many construction sites, soil moisture levels are often considered, especially in the initial assessment stage in complex geological environments or when precise measurement conditions are lacking. Construction workers tend to predict the trend of grounding resistance changes based on the surface soil moisture content. However, this assessment method based on surface environmental characteristics has serious technical flaws. Soil moisture distribution in the natural environment is often uneven, especially in areas with frequent climate changes, where the moisture content of the surface soil and deep soil often differs significantly. For example, after a short period of heavy rainfall, the surface soil rapidly absorbs moisture and becomes wet, significantly improving its conductivity. This can easily create the illusion for construction workers that the grounding environment has been greatly improved.

[0004] However, in reality, water infiltration into the ground requires a considerable amount of time and specific geological conditions. The deep soil where the grounding device is located, as well as the surrounding medium, may still be dry. This significant inconsistency between the surface and deep environments means that changes in surface moisture cannot accurately reflect the actual current dissipation resistance of the deep grounding device, leading to serious misjudgments of construction quality. Furthermore, the relationship between soil moisture content and grounding resistance is affected by the sampling location. If the sampling point is not within the effective current dissipation area of ​​the grounding device, changes in surface soil moisture cannot accurately reflect the actual state of the soil around the grounding device. This misjudgment caused by locational bias has become a problem that urgently needs to be addressed.

[0005] For example, during construction in the rainy season, the surface soil becomes wet due to rainfall, which may lead construction workers to believe that the grounding resistance will decrease. However, in reality, the deeper soil on the sidewalls of the grounding device is unaffected, and its resistance value may still be high. This difference between the surface and deep layers directly leads to deviations in the compliance determination. Therefore, accurately identifying whether the sampling location is within the effective current dissipation area during construction and dynamically adjusting the resistance compliance judgment criteria based on location differences has become a key issue in improving the accuracy of construction quality assessment. Summary of the Invention

[0006] This invention provides an automatic method for determining whether the resistance meets standards during the construction of a power distribution network grounding system. The method includes:

[0007] Deploy moisture content sensing elements and depth positioning encoders to collect initial and re-measurement readings of grounding resistance and moisture content, sampling location labels, and construction dates to form raw data sets;

[0008] Based on the sampling location labels, the boundary of the preset effective runoff zone is verified, the soil layer where the sampling point is located is identified, and the effective sampling subgroup is obtained;

[0009] Analyze the moisture content readings and grounding resistance readings in the effective sampling subgroups, extract the initial and remeasured increase of moisture content in the backfill surface, the grounding resistance reading of the undisturbed soil on the sidewall, and the initial and remeasured difference in grounding resistance to form a moisture resistance contradiction label;

[0010] Based on the moisture resistance contradiction label triggering the seasonal verification, the last rainfall interval and freeze-thaw status are read from the seasonal working condition record corresponding to the construction date, the resistance compliance judgment calibrated, and a seasonal assessment conclusion is formed.

[0011] By analyzing the difference between the initial and retest values ​​of the moisture content and grounding resistance in the sampling records corresponding to the contradictory moisture resistance labels, we obtained the water-affected traces of the surface backfill soil and the unwetted traces of the original soil on the side wall, thus confirming the conclusion that the surface moisture increase was a misjudgment.

[0012] Sampling records outside the diffusion zone that contain false conclusions about surface humidification are screened out. The grounding resistance and moisture content readings bound to the sampling location tags within the effective diffusion zone are collected to generate a judgment data set.

[0013] Input the judgment data group into the effective current-dissipating area grounding resistance acceptance rules, select the compliance threshold according to the seasonal assessment conclusion, verify whether the grounding resistance readings of each sampling point meet the construction acceptance limit, and output the resistance compliance conclusion of the distribution network grounding construction process.

[0014] Preferably, the deployment of the moisture content sensing element and depth positioning code disk collects initial and re-measurement readings of grounding resistance and moisture content, sampling location labels, and construction dates to form a raw data set, including:

[0015] The moisture content sensing chip acquires the moisture content readings of the backfill soil and the original soil, and the depth position code disk records the depth position of the sampling point, thus obtaining the initial grounding resistance reading and the initial moisture content reading with the sampling position label.

[0016] For the sampling points corresponding to the initial measurement readings, re-measurements are carried out. The initial measurement readings, re-measurement readings, sampling location labels, and construction dates are bound to each sampling point to form an original data set.

[0017] Preferably, the step of verifying the preset effective runoff zone boundary based on the sampling location label, identifying the soil layer location of the sampling point, and obtaining an effective sampling subgroup includes:

[0018] Parse the sampling location labels in the original data set, and extract the soil layer location identifier and depth scale value from the sampling location labels;

[0019] Retrieve the pre-calibrated boundary of the effective runoff zone. The boundary of the effective runoff zone is referenced to the grounding electrode, and it covers the area of ​​the original soil and backfill soil on the side wall in the radial direction, and the depth range from the bottom of the grounding electrode to the ground surface in the longitudinal direction. Compare the soil layer location marker with the depth scale value to the boundary of the effective runoff zone.

[0020] If the soil layer location marker and the depth scale value fall within the boundary of the effective runoff zone, the sampling point is determined to be within the runoff zone. The effective sampling subgroup is obtained by maintaining the pairing relationship between the grounding resistance reading and the moisture content reading of the sampling point within the runoff zone.

[0021] Preferably, the analysis of the moisture content readings and grounding resistance readings in the effective sampling subgroups, extracting the initial and remeasured increase in moisture content of the backfill surface layer, the grounding resistance reading of the undisturbed soil on the sidewall, and the initial and remeasured difference in grounding resistance, forms a moisture resistance discrepancy label, including:

[0022] The initial and retest readings of the backfill surface moisture content and the grounding resistance of the original soil on the sidewall are extracted from the effective sampling subgroup according to the soil layer location. The initial and retest increases of the backfill surface moisture content and the initial and retest differences of the grounding resistance are obtained by subtracting the initial and retest values ​​from the retest values.

[0023] If the increase in the initial and remeasured moisture content of the backfill surface exceeds a preset wetting threshold, the reading of the grounding resistance of the original soil on the sidewall exceeds a preset impedance threshold, and the difference between the initial and remeasured grounding resistance is lower than a preset change threshold, the wet resistance contradiction label is attached to the sampling location label.

[0024] Preferably, the seasonal verification triggered based on the wet resistance contradiction label involves reading the last rainfall interval and freeze-thaw status from the seasonal working condition record corresponding to the construction date, calibrating the resistance compliance judgment calibrator, and forming a seasonal assessment conclusion, including:

[0025] A seasonal verification request is triggered for the sampling location tag with the wet resistance contradiction tag, and the target record entries in the same area and time period in the preset seasonal working condition record are matched according to the construction date.

[0026] The last rainfall interval and the freeze-thaw status are read from the target record entry. The last rainfall interval is the time from the construction date to the last rainfall event. The freeze-thaw status is an indicator of the freezing period, thawing period, or normal temperature period in which the construction date is located.

[0027] If the interval between the last rainfalls is less than the preset infiltration duration threshold, the resistance standard is adjusted upward by a preset range; if the freeze-thaw state is in the freezing or thawing period, the resistance standard is adjusted downward by a preset range, and the data is attached to the sampling location label to form the seasonal assessment conclusion.

[0028] Preferably, the step of analyzing the difference between the initial and retested moisture content and grounding resistance of the sampling records corresponding to the contradictory moisture resistance labels to obtain water-affected traces in the surface backfill soil and unwetted traces in the undisturbed soil on the sidewalls, and confirming the misjudgment of surface moisture increase, includes:

[0029] For the sampling records with the aforementioned contradictory moisture resistance tags, the initial and subsequent measurements of the increase in the moisture content of the backfill surface layer and the initial and subsequent measurements of the grounding resistance of the undisturbed soil on the sidewall are extracted. If the initial and subsequent measurements of the increase in the moisture content of the backfill surface layer are higher than a preset wetting threshold, it is determined that there are traces of water absorption in the surface backfill soil. If the absolute value of the initial and subsequent measurements of the grounding resistance of the undisturbed soil on the sidewall is lower than a preset change threshold, it is determined that there are traces of unwetting in the undisturbed soil on the sidewall. If both traces of water absorption in the surface backfill soil and traces of unwetting in the undisturbed soil on the sidewall exist simultaneously, the conclusion of the surface wetting error is confirmed in the sampling records.

[0030] Preferably, the step of filtering out sampling records outside the diffused flow area that contain false conclusions about surface humidification, and collecting the grounding resistance and moisture content paired readings within the effective diffused flow area using sampling location tags to generate a judgment data set, includes:

[0031] Sampling records that are outside the effective flow diffusion zone and carry the false judgment of surface humidification in the original data set are filtered out to obtain the remaining sampling record set; sampling records that are within the effective flow diffusion zone are taken out from the remaining sampling record set, and the grounding resistance reading and moisture content reading in each sampling record are bound as a pair according to the sampling location label and collected to generate the judgment data set.

[0032] Preferably, the step of inputting the judgment data set into the effective current-dissipating area grounding resistance acceptance rules, selecting the compliance threshold according to the seasonal assessment conclusion, verifying whether the grounding resistance readings of each sampling point meet the construction acceptance limits, and outputting the resistance compliance conclusion of the distribution network grounding construction process includes:

[0033] For sampling locations that carry the seasonal assessment conclusion, the compliance threshold is selected according to the calibrated judgment standard; for sampling locations that do not carry the seasonal assessment conclusion, the compliance threshold is selected according to the original resistance compliance judgment standard.

[0034] Using the aforementioned compliance threshold as the construction acceptance limit, the grounding resistance readings under the labels of each sampling location are compared with the aforementioned construction acceptance limit. If all sampling points meet the standard, the conclusion that the resistance meets the standard is output; if there are sampling points that do not meet the standard, the conclusion that the resistance does not meet the standard is output.

[0035] The technical solutions provided by the embodiments of the present invention may include the following beneficial effects:

[0036] This invention discloses an automatic method for determining the resistance compliance during distribution network grounding construction. It addresses the contradiction between surface backfill soil humidification and the lack of moisture in the original sidewall soil during distribution network grounding construction, as well as the operational scenario where seasonal environmental changes can easily lead to misjudgments of resistance compliance. This invention uses a moisture content sensing chip and a depth positioning code disk to collect initial and retest data. It extracts the moisture content increase and resistance difference to form a moisture resistance contradiction label, which triggers seasonal verification by reading rainfall intervals and freeze-thaw conditions to calibrate the judgment criteria. Simultaneously, based on this label, it confirms the misjudgment conclusion due to surface humidification, filters out erroneous sampling records, and collects paired readings within the effective current dissipation zone to generate a judgment data set. Finally, it verifies the resistance reading using a compliance threshold selected according to the seasonal assessment conclusion. This invention effectively eliminates the interference of local surface humidification and seasonal operating conditions on grounding resistance measurement, significantly improving the accuracy and reliability of construction acceptance judgment. Attached Figure Description

[0037] Figure 1 This is a flowchart of an automatic method for determining whether the resistance of a distribution network grounding construction process meets the standards, according to the present invention.

[0038] Figure 2 This is a schematic diagram of an automatic method for determining whether the resistance of a distribution network grounding construction process meets the standards, according to the present invention.

[0039] Figure 3 This is another schematic diagram of an automatic method for determining whether the resistance meets the standard during the construction process of a power distribution network grounding, according to the present invention. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and thoroughly described below with reference to the accompanying drawings. The described embodiments are merely some embodiments of the present invention.

[0041] like Figures 1-3 This embodiment of an automatic method for determining whether the resistance meets the standard during the construction process of a distribution network grounding system may specifically include:

[0042] Step S101: Deploy a moisture content sensing chip and a depth position code disk in the grounding construction resistance determination system to collect the initial and re-measurement readings of grounding resistance and moisture content, sampling position labels and construction dates to form a raw data set.

[0043] Moisture content sensing elements and depth positioning codes are deployed at the grounding construction site. The moisture content sensing elements acquire moisture content readings of the backfill and undisturbed soil, while the depth positioning codes record the depth position of the sampling points, resulting in initial grounding resistance and initial moisture content readings labeled with the sampling location. Re-measurements are then performed at each sampling point corresponding to the initial measurement readings to obtain re-measured grounding resistance and moisture content readings. The initial measurement readings, re-measured readings, sampling location labels, and construction dates are linked line by line for each sampling point, forming a raw data set.

[0044] In the implementation scenario of determining the grounding resistance of a distribution network, a moisture content sensing element is a thin, sheet-like sensing element that detects soil moisture based on changes in dielectric constant. It infers the percentage of water in a unit volume of soil by calculating the capacitance between its two electrodes, outputting the moisture content reading as a percentage. In one embodiment, the moisture content sensing element is attached to both the backfill area and the undisturbed soil area of ​​the grounding electrode pit, forming parallel acquisition channels for the two types of soil layers. A depth position encoder is installed on the side of the probe. As the probe is pushed downwards, the encoder rotates and outputs the corresponding depth scale value. This scale value is then paired with the markings of soil layers such as backfill, undisturbed soil, and the bottom of the grounding electrode to obtain a sampling location label. Preferably, the sampling location label uses a character combination of "soil layer location + depth scale" to distinguish the affiliation of different sampling points.

[0045] Specifically, the initial reading of the grounding resistance is read simultaneously by a clamp meter connected to the grounding electrode at the same time as the moisture content sensing element completes the moisture collection, so that the moisture content reading and the resistance reading are aligned in time.

[0046] In one embodiment, after the initial measurement is completed, a second measurement is performed at the same location after a preset time interval to obtain the moisture content remeasurement reading and the grounding resistance remeasurement reading. The two readings together reflect the state change of the same sampling point within the interval period.

[0047] It should be noted that the construction date is written into the construction record at the start of the initial measurement and is bound to the initial measurement reading, remeasurement reading, and sampling location label one by one according to the sampling point to form the original data group. The original data group is saved with the sampling point as the smallest unit for subsequent flow area verification and compliance determination.

[0048] Step S102: Verify the preset effective runoff zone boundary based on the sampling location label, identify the soil layer where the sampling point is located, and obtain the effective sampling subgroup.

[0049] The sampling location labels in the original data set are analyzed, and soil layer identification and depth scale values ​​are extracted from these labels. The pre-defined effective runoff zone boundary is retrieved. This boundary, with the grounding electrode as a reference, radially encompasses the undisturbed soil and backfill soil of the sidewall, and longitudinally encompasses the depth range from the bottom of the grounding electrode to the ground surface. The soil layer identification and depth scale values ​​are compared to the effective runoff zone boundary. If the soil layer identification and depth scale values ​​fall within the effective runoff zone boundary, the sampling point is determined to be within the runoff zone. Based on the pairing relationship between the grounding resistance reading and moisture content reading retained for sampling points within the runoff zone, an effective sampling subgroup is obtained.

[0050] Sampling location labels are characterized identifiers used to describe the spatial location of each sampling. In one implementation, the sampling location label uses a composite string format of "soil layer location identifier + depth scale value". For example, "HT-035" represents a sampling point with a depth scale of 35 cm in the backfill soil area, and "YZ-080" represents a sampling point with a depth scale of 80 cm in the undisturbed soil area on the sidewall. Each record in the original data set carries the sampling location label. During parsing, the string is split according to a preset delimiter to obtain independent soil layer location identifiers and depth scale values.

[0051] Specifically, the soil layer location markers correspond to three types of media areas: backfill soil, original sidewall soil, and bottom contact soil of the grounding electrode. The depth scale value records the vertical distance of the sampling point relative to the ground surface. Together, they determine the spatial coordinates of the sampling point in the grounding electrode pit.

[0052] It should be noted that the effective current dissipation zone boundary is the geometric interface of the soil area where the current density decays to a preset level during the fault current discharge process of the grounding device. At the distribution network grounding construction site, this boundary is defined as follows: with the vertical axis of the grounding electrode as a reference, it radially covers a certain distance extending outward from the outer wall of the grounding electrode, and longitudinally covers a certain depth extending from the top to the bottom of the grounding electrode.

[0053] In one embodiment, the radial range is taken as a multiple of the grounding electrode radius, the lower longitudinal edge extends downward from the bottom of the grounding electrode, and the upper edge connects with the top layer of backfill soil. The boundary of the effective current dissipation zone is pre-calibrated in the form of a closed curved surface and stored in a boundary library for retrieval. The boundary library is indexed by the grounding electrode specification and the electrode pit depth, and the corresponding boundary geometric parameters are retrieved when different specifications of grounding devices are used. Preferably, in a scenario where horizontal and vertical grounding electrodes are mixed, the boundary of the effective current dissipation zone is formed by splicing a strip-shaped area of ​​the horizontal segment and a columnar area of ​​the vertical segment. The boundary is recorded in the form of a piecewise function, and during analysis, the corresponding boundary segment is selected according to the grounding electrode segment where the sampling point is located.

[0054] In one possible implementation, the process of comparing the soil layer location marker with the depth scale value to the boundary of the effective runoff zone is specifically manifested as follows: since the soil layer location marker itself represents the lateral region belonging of the sampling point, the lateral boundary segment into which the sampling point should fall is first located based on the soil layer location marker, and then the longitudinal interval defined by the depth scale value is checked based on whether it is within the segment, thereby completing the internal and external determination.

[0055] For example, in the sampling point marked as sidewall 080, the transverse area of ​​the undisturbed soil of the sidewall is checked to see if the depth of 80 cm of this point is within the longitudinal range defined by the undisturbed soil of the sidewall. If it falls into the range, it is recorded as within the flow zone; otherwise, it is recorded as outside the flow zone.

[0056] Understandably, for sampling points whose verification results fall outside the boundary, the grounding resistance and moisture content readings of such sampling points are still retained in the original data set, but are not included in the effective sampling subgroup. Instead, they are saved separately as sampling records outside the diffusion zone, serving as input for subsequent misjudgment identification. The effective sampling subgroup is organized with sampling points as the smallest unit. Each unit retains the pairing relationship between grounding resistance readings, moisture content readings, sampling location labels, and construction dates. Initial and retest readings are respectively attached to the corresponding sampling points, allowing the readings of the backfill area and the undisturbed soil area of ​​the sidewall to be compared in the same spatial coordinates, thereby accurately reflecting the true diffusion state of the medium around the grounding device.

[0057] Step S103: Analyze the moisture content readings and grounding resistance readings in the effective sampling subgroups, extract the initial and remeasured increase of the moisture content of the backfill surface, the grounding resistance reading of the undisturbed soil on the side wall, and the initial and remeasured difference of the grounding resistance, and form a wet resistance contradiction label.

[0058] From the effective sampling subgroup, extract the initial and remeasured readings of the backfill surface moisture content and the initial and remeasured readings of the undisturbed grounding resistance of the sidewall soil according to the soil layer location. Subtract the initial measurement value from the remeasured value to obtain the initial and remeasured increase in backfill surface moisture content and the initial and remeasured difference in grounding resistance, respectively. Use the remeasured value from the initial and remeasured readings of the undisturbed grounding resistance of the sidewall soil as the undisturbed grounding resistance reading. If the initial and remeasured increase in backfill surface moisture content exceeds a preset wetting threshold, the undisturbed grounding resistance reading exceeds a preset impedance threshold, and the initial and remeasured difference in grounding resistance is lower than a preset change threshold, attach a wet-resistance contradiction tag to the sampling location label.

[0059] Specifically, the initial and subsequent measurements of the backfill surface moisture content increase, the difference between the grounding resistance reading of the undisturbed soil on the sidewall and the initial and subsequent measurements of the grounding resistance constitute the criteria for determining the wet resistance contradiction. At the distribution network grounding construction site, the backfill surface is located in the upper area of ​​the backfill soil in the grounding electrode pit, close to the ground surface, and is most directly affected by external moisture such as rainfall and watering; the undisturbed soil on the sidewall is located in the undisturbed soil layer around the grounding electrode pit wall, and is the main medium for current discharge from the grounding device. The difference in the state of these two types of areas is precisely the carrier of the wet resistance contradiction. In one embodiment, after extraction from the effective sampling subgroup according to the soil layer location identification, the initial and subsequent measurements of the backfill surface moisture content and the initial and subsequent measurements of the grounding resistance of the undisturbed soil on the sidewall are obtained. Each reading includes two fields: an initial measurement item and a subsequent measurement item. The initial measurement item is the reading collected immediately after the grounding construction is completed, and the subsequent measurement item is the reading collected again after a preset interval. The initial and subsequent measurements of the backfill surface moisture content were subtracted from the initial measurement values ​​for both types of readings to obtain the initial and subsequent increases in the backfill surface moisture content and the initial and subsequent differences in the grounding resistance. The initial and subsequent increases in the backfill surface moisture content reflect the change in surface soil moisture over the interval period; a positive value indicates an increase in moisture, and a negative value indicates a decrease in moisture. The initial and subsequent differences in the grounding resistance reflect the fluctuation in the current dissipation resistance of the grounding device over the interval period.

[0060] It should be noted that the retested value in the initial retested reading of the original soil grounding resistance of the sidewall is used as the reading of the original soil grounding resistance of the sidewall because the retested value is closer to the current dissipation state and can characterize the true impedance level of the deep soil around the sidewall of the grounding device.

[0061] It is understandable that the values ​​of the preset wetting threshold, preset impedance threshold, and preset change threshold are determined based on engineering experience in judging the grounding construction resistance.

[0062] In one embodiment, the preset wetting threshold is 5 percentage points, meaning that if the moisture content of the retested soil increases by more than 5 percentage points compared with the initial test, it is considered that the surface is significantly wet; the preset impedance threshold is 0.9 times the construction acceptance limit of the grounding device of this specification, meaning that the reading of the grounding resistance of the original soil on the side wall has approached or exceeded the acceptance limit; the preset change threshold is 5% of the initial test reading, meaning that the grounding resistance has not decreased significantly within the interval period.

[0063] In one possible implementation, the logical combination of the three conditions is an AND relationship. That is, a moisture-resistance contradiction label is attached to the sampling location only if the initial and subsequent measurements of the backfill surface moisture content increase exceed a preset wetting threshold, the reading of the undisturbed soil grounding resistance of the sidewall exceeds a preset impedance threshold, and the initial and subsequent measurements of the grounding resistance difference are lower than a preset change threshold. If any one of the three conditions is not met, the location will not be included in the contradiction candidate list.

[0064] For example, at a sampling point labeled "HT-020" for backfill surface layer, the initial moisture content was 12%, and the retested moisture content was 22%, with an increase of 10 percentage points between the initial and retested values, exceeding the preset moisture threshold. In the same area, at a sampling point labeled "YZ-090" for undisturbed soil on the side wall, the retested grounding resistance was a relatively high value close to the acceptance limit, exceeding the preset impedance threshold. Moreover, the difference between the initial and retested values ​​was only 2% of the initial value, which was lower than the preset change threshold. Therefore, a moisture resistance contradiction label was attached to the "HT-020" sampling point label.

[0065] Preferably, the wet resistance contradiction label is stored in key-value pair format, where the key is the sampling location label and the value includes four fields: contradiction status code, initial and retested increase in backfill surface moisture content, grounding resistance reading of the original soil on the side wall, and initial and retested difference in grounding resistance. This facilitates the retrieval of the corresponding sampling record by label for further analysis in the subsequent seasonal verification process.

[0066] Understandably, the presence of the contradictory wet resistance label indicates that the sampling location exhibits an inconsistent situation where surface moisture rises while the deep diffusion state has not improved synchronously. This is a typical example that is prone to misjudgment in the grounding construction quality assessment and requires further verification in subsequent stages.

[0067] Step S104: Based on the wet resistance contradiction label, trigger seasonal verification, read the last rainfall interval and freeze-thaw status from the seasonal working condition record corresponding to the construction date, calibrate the resistance compliance judgment calibrator, and form a seasonal assessment conclusion.

[0068] A seasonal verification request is triggered for the sampling location tag bearing the wet resistance contradiction tag. The system matches the target record entry in the same region and time period from the preset seasonal working condition records according to the construction date. The last rainfall interval and freeze-thaw status are read from the target record entry. The last rainfall interval is the time elapsed since the last rainfall event, and the freeze-thaw status indicates whether the construction date falls within the freezing, thawing, or normal temperature period. Using the original resistance compliance criterion as the calibration starting point, if the last rainfall interval is less than a preset infiltration duration threshold, the resistance compliance criterion is increased by a preset margin; if the freeze-thaw status is in the freezing or thawing period, the resistance compliance criterion is decreased by a preset margin. The calibrated criterion is then attached to the sampling location tag corresponding to the wet resistance contradiction tag, forming a seasonal assessment conclusion.

[0069] Specifically, in determining the grounding construction resistance, the "wet surface, dry deep layer" situation revealed by the wet resistance contradiction label is only a spatial inconsistency, and the impact of this inconsistency varies under different seasonal conditions. In one implementation, a seasonal verification request is triggered for the sampling location label bearing the wet resistance contradiction label. This request, with the sampling location label and construction date as input parameters, is submitted to the seasonal condition query interface to initiate subsequent reading actions.

[0070] It should be noted that the preset seasonal working condition records are a collection of working condition data entries pre-compiled by region, month, or solar term. Each entry contains at least four fields: region identifier, time period identifier, last rainfall interval, and freeze-thaw status. The entry collection forms a two-dimensional index by region and time period. During matching, the specific time period within the year is mapped according to the construction date, and the target record entry for the same time period in the same region is retrieved according to the region to which the construction site belongs. The last rainfall interval is measured in hours or days, recording the difference in time between the construction date and the start and end time of the last rainfall event. For example, if the construction date is the afternoon of the 15th of a certain month, and the last rainfall event ended on the morning of the 14th, the last rainfall interval is approximately 30 hours. The freeze-thaw status is characterized by three categories: freezing period, thawing period, and normal temperature period, representing the climate stage at which the construction date is located.

[0071] In one embodiment, the freezing period corresponds to the time when the surface temperature of the construction site area is below 0 degrees Celsius both day and night; the thawing period corresponds to the transition period when the daytime temperature rises above 0 degrees Celsius but the nighttime temperature remains below 0 degrees Celsius; and the normal temperature period corresponds to the time when the daytime and nighttime temperatures are consistently above 0 degrees Celsius. The freeze-thaw state is pre-defined in the seasonal operating condition records and does not require immediate determination during the calibration phase. The calibration starting point is based on the original resistance compliance criterion, which is derived from the limit value of the corresponding grounding device specification in the grounding engineering acceptance code, typically expressed in ohms, and serves as the initial criterion for whether the resistance reading meets the standard.

[0072] In one possible implementation, if the interval between the last rainfalls is less than a preset infiltration time threshold, it means that the last rainfall was relatively close to the construction time, and the surface moisture has not yet fully infiltrated into the deep medium. The diffusion conditions of the soil around the sidewall of the grounding device are overestimated by the surface wet state. In this case, the resistance compliance judgment caliber is increased by a preset range, making the judgment limit more stringent. The preset infiltration time threshold is given according to the geological type of the construction site. The value is longer in clay areas, such as 48 to 72 hours; and shorter in sandy areas, such as 12 to 24 hours. The preset range can be 5% to 15% of the original caliber. If the freeze-thaw state is in the freezing or thawing period, it means that there are ice crystals or ice-water coexisting phases in the deep soil. The conductivity of the medium is non-steady, and the grounding resistance reading is significantly affected by the phase fluctuation. In this case, the resistance compliance judgment caliber is decreased by a preset range, making the judgment limit more lenient and avoiding misjudging the short-term high grounding resistance during the freeze-thaw period as non-compliant.

[0073] In one embodiment, the reduction in the freezing period is greater than that in the thawing period, for example, the freezing period is reduced by 15% while the thawing period is reduced by 8%.

[0074] It is understandable that the upward adjustment triggered by the last rainfall interval and the downward adjustment triggered by the freeze-thaw state are not mutually exclusive. If both conditions are met at the same time, the adjustment is first made upward according to the last rainfall interval, and then downward according to the freeze-thaw state. The superimposed caliber is used as the calibrated judgment caliber.

[0075] For example, if the construction date of a grounding electrode pit in a distribution network is December 10th of a certain year, and the area is located in the northern permafrost zone, and the last rainfall interval is 120 hours and the freeze-thaw state is in the freezing period, then the last rainfall interval exceeds the preset infiltration time threshold, and no upward adjustment action is triggered; if the freeze-thaw state is in the freezing period, a downward adjustment action is triggered, and the original resistance compliance judgment calibrator is reduced by 15%, resulting in a calibrated judgment calibrator. Preferably, the seasonal assessment conclusion is stored in the form of a record entry, with fields including the sampling location label corresponding to the wet resistance contradiction label, the original resistance compliance judgment calibrator, the calibrated judgment calibrator, the last rainfall interval, and the freeze-thaw state, which are attached to the sampling location label for subsequent acceptance calibrator retrieval. The existence of this seasonal assessment conclusion allows the grounding construction resistance compliance judgment to dynamically adjust the limit calibrator according to climatic conditions, providing an executable criterion under the climatic conditions while retaining the contradiction status record.

[0076] Step S105: By analyzing the difference between the initial and retest values ​​of the moisture content and grounding resistance in the sampling records corresponding to the wet resistance contradiction label, the water-affected traces of the surface backfill soil and the unwetted traces of the original soil on the side wall are obtained, and the conclusion of misjudgment of surface humidification is confirmed by the water-affected traces of the surface backfill soil and the unwetted traces of the original soil on the side wall.

[0077] For the sampling records with the aforementioned contradictory moisture resistance tags, extract the initial and remeasured increase in the moisture content of the backfill surface layer and the initial and remeasured difference in the grounding resistance of the undisturbed soil on the sidewall. If the initial and remeasured increase in the moisture content of the backfill surface layer is higher than a preset wetting threshold, the backfill surface layer is recorded as having water damage. If the absolute value of the initial and remeasured difference in the grounding resistance of the undisturbed soil on the sidewall is lower than a preset change threshold, and the reading of the grounding resistance of the undisturbed soil on the sidewall is higher than a preset impedance threshold, the undisturbed soil on the sidewall is recorded as having no wetting. If both the water damage to the backfill surface layer and the no wetting of the undisturbed soil on the sidewall are established simultaneously, confirm the misjudgment of surface wetting in the sampling record and write the misjudgment of surface wetting into the judgment field of the sampling location tag.

[0078] Specifically, misjudgment of surface humidification is a common source of deviation in grounding construction resistance determination. This is caused by construction personnel or automated judgment processes mistakenly extrapolating the surface soil's moisture state to deeper media, leading to an overly optimistic estimate of the grounding device's current dissipation conditions. The moisture-resistance contradiction label identifies sampling locations with this risk of deviation. Further verification at these sampling locations using the coexistence of two types of traces is needed to confirm whether the deviation actually exists. For sampling records bearing the moisture-resistance contradiction label, three characteristic values ​​are extracted: the initial and remeasured increase in backfill surface moisture content, the initial and remeasured difference in grounding resistance of the undisturbed sidewall soil, and the initial measurement reading of the grounding resistance of the undisturbed sidewall soil. The extracted initial measurement reading of the grounding resistance of the undisturbed sidewall soil is denoted as R and used to calculate the preset change threshold T. The calculation formula is T = R × 0.05, where T is the preset change threshold and R is the initial measurement reading of the grounding resistance of the undisturbed sidewall soil.

[0079] For example, when R is 100 ohms, T = 5 ohms. That is, if |retest value - initial test value| < 5 ohms, it is considered that the difference between the initial and retest grounding resistance is lower than the preset change threshold. The three characteristic values ​​have been paired and bound to the sampling location label and sampling point in the previous step. The extraction action is directly retrieved through key value retrieval and does not participate in the reading acquisition again.

[0080] It should be noted that water-received marks on the surface backfill soil are physical traces indicating that the upper part of the backfill soil in the grounding electrode pit has clearly received external moisture input. At power distribution network grounding construction sites, common sources of these marks include rapid moisture absorption by the surface soil after short-term heavy rainfall, a short-term spike in surface moisture content after dust suppression spraying, and water filling the gaps between particles in the upper part of the backfill soil after surface runoff enters the pit. In one embodiment, the determination of water-received marks on the surface backfill soil is based on the positional relationship between the initial and subsequent increases in the surface moisture content and a preset wetting threshold. The preset wetting threshold is pre-calibrated according to the backfill soil texture; a smaller wetting threshold is used for cohesive backfill soil, such as 3 to 5 percentage points; and a larger wetting threshold is used for sandy backfill soil, such as 5 to 8 percentage points. If the increase in the initial and subsequent measurements of the backfill surface moisture content is higher than the preset wetting threshold, then the water-affected trace of the backfill soil is recorded and attached to the trace field of the sampling location label in the form of a binary marker. If the increase in the initial and subsequent measurements of the backfill surface moisture content is not higher than the preset wetting threshold, then the water-affected trace of the backfill soil is recorded as invalid, and subsequent processes will not confirm the erroneous humidification judgment for this sampling location. Based on the above determination of the water-affected trace, the deep medium around the grounding electrode sidewall is further determined to determine whether it is synchronously wetted. Specifically, the unwetting trace of the undisturbed soil on the sidewall is a physical trace describing that the undisturbed soil layer around the grounding electrode sidewall is not wetted by water and the diffusion state is not synchronously improved. The determination of this trace relies on the coexistence of two conditions: first, the absolute value of the difference between the initial and subsequent measurements of the grounding resistance of the undisturbed soil on the sidewall is lower than the preset change threshold, meaning that the grounding resistance has not decreased significantly during the interval between the initial and subsequent measurements; second, the reading of the grounding resistance of the undisturbed soil on the sidewall is higher than the preset impedance threshold, meaning that the current value of the grounding resistance is still at a relatively high level. When both conditions are met, the mark of unwetted soil on the side wall is established.

[0081] In one embodiment, the preset change threshold is set as 5% of the initial resistance reading as the lower limit, meaning that if the difference between the remeasured grounding resistance value and the initial measurement value does not exceed 5%, it is considered that no significant decrease has occurred; the preset impedance threshold is set as 0.9 times the construction acceptance limit of the grounding device of this specification, meaning that if the grounding resistance is close to the upper limit of acceptance, it is considered too high. Both conditions use the positional relationship between the reading and the threshold as the criterion, without involving secondary transformation of the reading itself.

[0082] It is understandable that if both the water-receiving marks on the surface backfill soil and the unwetted marks on the undisturbed sidewall soil are present simultaneously, it means that the sampling location exhibits two opposing trends: "increasing surface moisture" and "unimproved deep runoff conditions." This conforms to the typical pattern of misjudgment of surface moisture increase, and the conclusion of misjudgment of surface moisture increase is confirmed for this sampling record. If either of the two types of marks is not present, the conclusion of misjudgment of surface moisture increase is not confirmed, and only the moisture resistance contradiction label is retained for this sampling location, moving to other analysis paths. Preferably, the conclusion of misjudgment of surface moisture increase is written into the analysis field of the sampling location label. The analysis field is an extended storage bit under the sampling location label, and the field content includes at least four items: misjudgment conclusion marker, initial and remeasured increase in backfill surface moisture content, grounding resistance reading of undisturbed sidewall soil, and initial and remeasured difference in grounding resistance of undisturbed sidewall soil. These serve as the input basis for the subsequent screening of sampling records outside the runoff area.

[0083] It should be noted that the method of confirming the misjudgment of surface humidification by the coexistence of the two types of traces makes the misjudgment path of inferring the improvement of deep diffusion based solely on surface humidity explicitly identified in the distribution network grounding construction resistance determination process, thus preventing such sampling locations from entering the subsequent acceptance verification stage with criteria that deviate from reality.

[0084] Step S106: Screen out sampling records outside the diffused flow area that contain false conclusions of surface humidification, and collect the grounding resistance and moisture content paired readings bound to the sampling location tags in the effective diffused flow area to generate a judgment data group.

[0085] An initial dataset, consisting of grounding resistance readings, moisture content readings, sampling location labels, and the status of the diffusion zone, is obtained and compiled from previous field measurements and is considered the raw data set. Sampling records outside the effective diffusion zone that carry the false conclusion of surface humidification are removed from this raw data set, resulting in a remaining set of sampling records. Sampling records within the effective diffusion zone are then extracted from this remaining set. The grounding resistance reading and moisture content reading in each sampling record are paired according to the sampling location labels and aggregated to generate a judgment data set.

[0086] Specifically, the judgment field and sampling location label of each sampling record are retrieved in the original data group. The sampling location label contains information on the soil layer location of the geological structure where the sampling point is located and the depth value from the ground surface. If the judgment field contains the surface humidification misjudgment conclusion marker and the soil layer location and depth value recorded in the sampling location label fall outside the effective runoff area, the sampling record is removed from the original data group, and the remaining sampling records constitute the remaining sampling record set.

[0087] It should be noted that the remaining sampling record set retains both the sampling records that are outside the effective flow diffusion zone but have not been attached to the surface humidification misjudgment conclusion and all the sampling records that are inside the effective flow diffusion zone. The former is retained as supplementary supporting material, and the latter is used as the sampling range for the judgment data group.

[0088] Preferably, the remaining sampling record set is filtered according to the soil layer location field of the sampling location label, and only sampling records within the effective runoff zone are retrieved. For each retrieved sampling record, the grounding resistance reading and moisture content reading are used as fields and attached to the sampling location label to form a pair. All pairs are collected in the same container with the sampling location label as the key and the grounding resistance reading and moisture content reading as the value, which is the judgment data set. The judgment data set retains the pairing relationship between the initial measurement and the remeasurement readings, as input for subsequent acceptance limit verification.

[0089] Step S107: Input the judgment data group into the effective current-dissipating area grounding resistance acceptance rules, select the compliance threshold according to the seasonal assessment conclusion, verify whether the grounding resistance readings of each sampling point meet the construction acceptance limit, and output the resistance compliance conclusion of the distribution network grounding construction process by judging whether the resistance meets the standard.

[0090] The judgment data set is input into the pre-established effective current-dissipating area grounding resistance acceptance rules. For sampling locations with the seasonal assessment conclusion attached, a compliance threshold is selected according to the calibrated judgment calibrator. For sampling locations without the seasonal assessment conclusion attached, a compliance threshold is selected according to the original resistance compliance judgment calibrator. Using the compliance threshold as the construction acceptance limit, the grounding resistance readings under the labels of each sampling location in the judgment data set are compared with the construction acceptance limit to obtain the compliance status mark of each sampling point. If the compliance status marks of all sampling points in the judgment data set are compliant, a resistance compliance conclusion is output; if there are non-compliant sampling points, a resistance non-compliant conclusion is output, which serves as the resistance compliance conclusion for the distribution network grounding construction process.

[0091] Specifically, the effective current-dissipating zone grounding resistance acceptance rules are a set of rules pre-compiled according to grounding engineering specifications and stored in the grounding construction resistance judgment process. Using grounding device specifications and soil layer location as indexes, it records the upper limit values ​​of grounding resistance corresponding to various sampling locations. The judgment data group serves as input, and the acceptance rules are queried using the sampling location label as the key, retrieving the upper limit value entry that matches the specification and soil layer location of that sampling location. In one embodiment, the acceptance rules are organized internally by a threshold table. Each row of the threshold table contains five fields: grounding device specification code, soil layer location identifier, upper limit value under the original resistance compliance judgment caliber, upper limit value under the upward adjustment level, and upper limit value under the downward adjustment level. The table lookup operation locates the specific row using the sampling location label as the index, and then selects the upper limit value of the corresponding column as the compliance threshold according to the judgment caliber. For example, if the input specification code is type 1 and the soil layer location identifier is surface layer, the corresponding row is matched using a hash lookup algorithm. If the judgment caliber is original resistance, the value of 10.5 ohms in the third column of that row is output as the compliance threshold.

[0092] It should be noted that there are two types of sampling locations in the judgment data group. The first type is sampling locations that have been triggered by the moisture-resistance contradiction tag and completed the seasonal verification. The moisture-resistance contradiction tag is an abnormal identifier automatically generated by the system when the relative humidity of the soil at the sampling location is greater than 80% and the initial measured value of the grounding resistance is greater than 10 ohms. This tag is used to identify the abnormal state of high humidity and high resistance and trigger the subsequent seasonal verification process. This type of sampling location carries the seasonal assessment conclusion, which stores the calibrated judgment calibrator, such as the specific calibrator marking of adjusting up or down by one level. The second type is sampling locations that have not triggered the seasonal verification. This type of sampling location does not carry the seasonal assessment conclusion, and the original resistance compliance judgment calibrator is used as the basis for value selection. For sampling locations carrying the seasonal assessment conclusion, the compliance threshold is selected according to the calibrated judgment calibrator.

[0093] For example, if the seasonal assessment conclusion for a sampling location indicates a one-level reduction in calibration, the value of the "lower level" field in the row containing the sampling location label in the threshold table is read as the compliance threshold. For sampling locations without the aforementioned seasonal assessment conclusion, the compliance threshold is selected according to the original resistance compliance determination calibrator; that is, the value of the "original calibrator" field in the row containing the sampling location label in the threshold table is read as the compliance threshold. Using this compliance threshold as the construction acceptance limit, the grounding resistance readings under each sampling location label in the determination data group are compared with the construction acceptance limit.

[0094] Preferably, the retested items saved under the sampling location label are used as the grounding resistance readings for comparison, because the retested items are closer to the current dissipation state. If the retested items are missing, the initial test items are used as the grounding resistance readings for comparison.

[0095] Understandably, the comparison is based on the relationship between the grounding resistance reading and the construction acceptance limit. If the grounding resistance reading does not exceed the construction acceptance limit, the compliance status of the sampling point is marked as compliant; if the grounding resistance reading exceeds the construction acceptance limit, the compliance status of the sampling point is marked as non-compliant. The compliance status mark is attached to the corresponding sampling location label in binary form. Further, the compliance status marks of all sampling points in the judgment data group are summarized. If the compliance status marks of all sampling points in the judgment data group are compliant, the resistance compliance conclusion is output, meaning that the distribution network grounding construction meets the acceptance limit at the sampling locations covered by the judgment data group; if at least one sampling point in the judgment data group is marked as non-compliant, the resistance non-compliant conclusion is output, and a list of non-compliant sampling location labels is attached to this conclusion.

[0096] For example, the output conclusion on the compliance of the resistance during the distribution network grounding construction process is saved in the form of a record. The fields include readable fields such as construction date, grounding device specifications, number of sampling points in the judgment data group, number of compliant sampling points, number of non-compliant sampling points, list of non-compliant sampling location labels, and final conclusion identifier, which serve as the final output basis for the quality assessment of this distribution network grounding construction.

[0097] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not describe the various possible combinations separately. Furthermore, various different embodiments of the present invention can also be arbitrarily combined, as long as they do not violate the spirit of the present invention, and should also be regarded as the content disclosed by the present invention.

Claims

1. A method for automatically determining whether the resistance meets the standard during the construction process of a power distribution network grounding system, characterized in that, The method includes: Deploy moisture content sensing elements and depth positioning encoders to collect initial and re-measurement readings of grounding resistance and moisture content, sampling location labels, and construction dates to form raw data sets; Based on the sampling location labels, the boundary of the preset effective runoff zone is verified, the soil layer where the sampling point is located is identified, and the effective sampling subgroup is obtained; Analyze the moisture content readings and grounding resistance readings in the effective sampling subgroups, extract the initial and remeasured increase of moisture content in the backfill surface, the grounding resistance reading of the undisturbed soil on the sidewall, and the initial and remeasured difference in grounding resistance to form a moisture resistance contradiction label; Based on the moisture resistance contradiction label triggering the seasonal verification, the last rainfall interval and freeze-thaw status are read from the seasonal working condition record corresponding to the construction date, the resistance compliance judgment calibrated, and a seasonal assessment conclusion is formed. By analyzing the difference between the initial and retest values ​​of the moisture content and grounding resistance in the sampling records corresponding to the contradictory moisture resistance labels, we obtained the water-affected traces of the surface backfill soil and the unwetted traces of the original soil on the side wall, thus confirming the conclusion that the surface moisture increase was a misjudgment. Sampling records outside the diffusion zone that contain false conclusions about surface humidification are screened out. The grounding resistance and moisture content readings bound to the sampling location tags within the effective diffusion zone are collected to generate a judgment data set. Input the judgment data group into the effective current-dissipating area grounding resistance acceptance rules, select the compliance threshold according to the seasonal assessment conclusion, verify whether the grounding resistance readings of each sampling point meet the construction acceptance limit, and output the resistance compliance conclusion of the distribution network grounding construction process.

2. The automatic method for determining whether the resistance meets the standard during the construction process of a power distribution network grounding, as described in claim 1, is characterized in that... The deployment of the moisture content sensing chip and depth positioning code disk collects initial and re-measurement readings of grounding resistance and moisture content, sampling location labels, and construction dates to form a raw data set, including: The moisture content sensing chip acquires the moisture content readings of the backfill soil and the original soil, and the depth position code disk records the depth position of the sampling point, thus obtaining the initial grounding resistance reading and the initial moisture content reading with the sampling position label. For the sampling points corresponding to the initial measurement readings, re-measurements are carried out. The initial measurement readings, re-measurement readings, sampling location labels, and construction dates are bound to each sampling point to form an original data set.

3. The automatic method for determining whether the resistance meets the standard during the construction process of a power distribution network grounding, as described in claim 1, is characterized in that... The process of verifying the preset effective runoff zone boundary based on the sampling location label, identifying the soil layer location of the sampling point, and obtaining an effective sampling subgroup includes: Parse the sampling location labels in the original data set, and extract the soil layer location identifier and depth scale value from the sampling location labels; Retrieve the pre-calibrated boundary of the effective runoff zone. The boundary of the effective runoff zone is referenced to the grounding electrode, and it covers the area of ​​the original soil and backfill soil on the side wall in the radial direction, and the depth range from the bottom of the grounding electrode to the ground surface in the longitudinal direction. Compare the soil layer location marker with the depth scale value to the boundary of the effective runoff zone. If the soil layer location marker and the depth scale value fall within the boundary of the effective runoff zone, the sampling point is determined to be within the runoff zone. The effective sampling subgroup is obtained by maintaining the pairing relationship between the grounding resistance reading and the moisture content reading of the sampling point within the runoff zone.

4. The automatic method for determining whether the resistance meets the standard during the construction process of a distribution network grounding, as described in claim 1, is characterized in that... The analysis of the moisture content readings and grounding resistance readings in the effective sampling subgroups extracts the initial and remeasured increase in moisture content of the backfill surface layer, the grounding resistance reading of the undisturbed soil on the sidewall, and the difference between the initial and remeasured grounding resistance, forming a moisture resistance discrepancy label, including: The initial and retest readings of the backfill surface moisture content and the grounding resistance of the original soil on the sidewall are extracted from the effective sampling subgroup according to the soil layer location. The initial and retest increases of the backfill surface moisture content and the initial and retest differences of the grounding resistance are obtained by subtracting the initial and retest values ​​from the retest values. If the increase in the initial and remeasured moisture content of the backfill surface exceeds a preset wetting threshold, the reading of the grounding resistance of the original soil on the sidewall exceeds a preset impedance threshold, and the difference between the initial and remeasured grounding resistance is lower than a preset change threshold, the wet resistance contradiction label is attached to the sampling location label.

5. The automatic method for determining whether the resistance meets the standard during the construction process of a distribution network grounding, as described in claim 1, is characterized in that... The seasonal verification is triggered based on the wet resistance contradiction label. The last rainfall interval and freeze-thaw status are read from the seasonal working condition record corresponding to the construction date. The resistance compliance judgment calibrated, and a seasonal assessment conclusion is formed, including: A seasonal verification request is triggered for the sampling location tag with the wet resistance contradiction tag, and the target record entries in the same area and time period in the preset seasonal working condition record are matched according to the construction date. The last rainfall interval and the freeze-thaw status are read from the target record entry. The last rainfall interval is the time from the construction date to the last rainfall event. The freeze-thaw status is an indicator of the freezing period, thawing period, or normal temperature period in which the construction date is located. If the interval between the last rainfalls is less than the preset infiltration duration threshold, the resistance standard is adjusted upward by a preset range; if the freeze-thaw state is in the freezing or thawing period, the resistance standard is adjusted downward by a preset range, and the data is attached to the sampling location label to form the seasonal assessment conclusion.

6. The automatic method for determining whether the resistance meets the standard during the construction process of a distribution network grounding, as described in claim 1, is characterized in that... The analysis of the moisture content and grounding resistance difference between the initial and remeasured values ​​of the sampling records corresponding to the contradictory moisture resistance labels yielded water marks on the surface backfill soil and unwetted marks on the undisturbed sidewall soil, confirming the misjudgment of surface moisture increase, including: For the sampling records with the aforementioned contradictory moisture resistance tags, the initial and subsequent measurements of the increase in the moisture content of the backfill surface layer and the initial and subsequent measurements of the grounding resistance of the undisturbed soil on the sidewall are extracted. If the initial and subsequent measurements of the increase in the moisture content of the backfill surface layer are higher than a preset wetting threshold, it is determined that there are traces of water absorption in the surface backfill soil. If the absolute value of the initial and subsequent measurements of the grounding resistance of the undisturbed soil on the sidewall is lower than a preset change threshold, it is determined that there are traces of unwetting in the undisturbed soil on the sidewall. If both traces of water absorption in the surface backfill soil and traces of unwetting in the undisturbed soil on the sidewall exist simultaneously, the conclusion of the surface wetting error is confirmed in the sampling records.

7. The automatic method for determining whether the resistance meets the standard during the construction process of a power distribution network grounding, as described in claim 1, is characterized in that... The process involves filtering out sampling records outside the diffused flow area that contain false conclusions about surface humidification, and then collecting paired readings of grounding resistance and moisture content within the effective diffused flow area, tagged with sampling location labels, to generate a judgment data set, including: Sampling records that are outside the effective flow diffusion zone and carry the false judgment of surface humidification in the original data set are filtered out to obtain the remaining sampling record set; sampling records that are within the effective flow diffusion zone are taken out from the remaining sampling record set, and the grounding resistance reading and moisture content reading in each sampling record are bound as a pair according to the sampling location label and collected to generate the judgment data set.

8. The automatic method for determining whether the resistance meets the standard during the construction process of a distribution network grounding, as described in claim 1, is characterized in that... The process involves inputting the judgment data set into the effective current-dissipating area grounding resistance acceptance rules, selecting the compliance threshold according to the seasonal assessment conclusion, verifying whether the grounding resistance readings at each sampling point meet the construction acceptance limits, and outputting the resistance compliance conclusion of the distribution network grounding construction process, including: For sampling locations that carry the seasonal assessment conclusion, the compliance threshold is selected according to the calibrated judgment standard; for sampling locations that do not carry the seasonal assessment conclusion, the compliance threshold is selected according to the original resistance compliance judgment standard. Using the aforementioned compliance threshold as the construction acceptance limit, the grounding resistance readings under the labels of each sampling location are compared with the aforementioned construction acceptance limit. If all sampling points meet the standard, the resistance is output as compliant; otherwise, if there are non-compliant sampling points, the resistance is output as non-compliant.

Images