A method for monitoring the state of a grounding resistor

Abstract

The application relates to a grounding resistance state monitoring method, and the technology comprises the following steps: acquiring grounding resistance continuous monitoring data, working condition information and collection state information of a target grounding object; dividing the continuous monitoring data according to the working condition information to obtain data segments with working condition parameters falling into the same preset range; screening the data segments according to the collection state information to obtain credible data segments satisfying preset credibility conditions; and establishing state memory anchor points based on historical credible data segments according to working conditions, wherein the state memory anchor points are used for representing the reference state of the grounding resistance under the corresponding working condition; compared with the prior art, the continuous monitoring data is divided according to working conditions in the application, and the credible data segments are screened in combination with the collection state, and then the state memory anchor points are established with the historical credible data under the same working condition, so that the comparison reference is limited to be carried out under comparable conditions, and the interference of working condition changes and sampling abnormalities on state judgment can be reduced.

Description

Technical Field

[0001] This invention relates to a method for monitoring the condition of a resistor, specifically a method for monitoring the condition of a grounding resistor. Background Technology

[0002] Grounding devices are fundamental safety units in power, communication, rail transit, industrial control, and lightning protection systems. Their grounding resistance directly affects fault current discharge capacity, equipment casing potential control, and personnel electric shock protection. In current engineering practice, grounding resistance is not a constant parameter but changes due to various factors such as soil moisture, corrosion and aging, loose connections, operating load, and on-site disturbances. In existing technologies, substandard grounding resistance in public distribution substations can easily lead to safety hazards such as residual current protection failure and electrified equipment casings. Furthermore, traditional manual measurement still suffers from problems such as requiring disconnection of grounding leads, high operational risks, large workload due to numerous and widespread measurement points, long detection cycles, and difficulty in timely reflecting changes in grounding status during operation. Therefore, in long-term operation scenarios, how to reliably identify true changes in the grounding status from continuous monitoring data has become a practical technical problem that needs to be solved in the field of grounding monitoring.

[0003] In recent years, technologies for online monitoring of grounding resistance have shifted from periodic offline measurements to online data acquisition and automatic calculation. For example, CN109765432B discloses a real-time monitoring system for the grounding resistance of a public distribution substation. This system uses a main controller, current sensors, voltage sensors, a controlled power frequency current generator, and a communication module to collect grounding current and residual grounding voltage. The system calculates the resistance using the formula R = residual grounding voltage / grounding current, and executes processing mechanisms such as uploading data, alarming, or cutting off the main circuit power supply within normal, alarm, and critical value ranges. Another example is CN116879635B, which discloses a monitoring scheme for shared grounding electrode scenarios. This scheme uses the neutral bus voltage values ​​and grounding electrode line current values ​​of the first and second converter stations, combined with the connection type and operating status, to select the appropriate resistance calculation formula to obtain the shared grounding electrode resistance. The former type of solution focuses on online data acquisition, threshold alarms, and linkage protection at the engineering site, while the latter type of solution focuses on the resistance calculation accuracy and operational adaptability under specific topological conditions. This indicates that the field has recognized that online monitoring of grounding resistance needs to be processed in combination with the operating status and on-site sampling conditions.

[0004] However, based on the publicly available technical content of the prior art, existing solutions mainly focus on how to measure the current resistance value or how to respond according to a threshold. The state discrimination chain under continuous monitoring conditions is not sufficiently disclosed. Especially when the target grounding object experiences different operating conditions, fluctuations in acquisition quality, on-site interference, or transient disturbances, the resistance shift occurring within the same time period may originate from actual degradation or may be caused solely by acquisition distortion, interference factors, or operating condition-induced factors. If judgment is made directly based on the current calculated value or static threshold, transient shifts are easily mistaken for degradation, or slow degradation is submerged in operating condition fluctuations, leading to false alarms, missed alarms, or even contamination of the baseline state by abnormal data. Compared to the aforementioned existing technologies, there is still a need in this field for a state monitoring method for continuous monitoring data: it should not only be able to segment the data according to the operating conditions and perform reliable screening in combination with the collection status, but also be able to establish a continuously evolving state benchmark under the same operating conditions, perform a counter-evidence review on the deviation first, and then confirm whether the state is advancing through supplementary sampling under the same operating conditions, thereby distinguishing the two technical levels of measured resistance value and determination of degradation, and improving the reliability of grounding resistance state monitoring results. Summary of the Invention

[0005] The purpose of this invention is to provide a method for monitoring the state of grounding resistance, thereby addressing some of the drawbacks and shortcomings pointed out in the background art.

[0006] The technical solutions adopted by the present invention to solve the above-mentioned technical problems include: Acquire continuous monitoring data of the grounding resistance, operating conditions, and acquisition status of the target grounding object; The continuous monitoring data is segmented according to the operating condition information to obtain data segments whose operating condition parameters fall within the same preset range; the data segments are then filtered according to the acquisition status information to obtain reliable data segments that meet preset reliability conditions. State memory anchors are established based on historical reliable data segments according to operating conditions. The state memory anchors are used to characterize the reference state of grounding resistance under the corresponding operating conditions. The newly acquired reliable data segments are compared with the state memory anchors corresponding to the current operating conditions. When the comparison difference exceeds the preset offset threshold, it is determined that an offset has occurred and the offset direction is determined. The occurrence of offsets is subject to a priority review of evidence to distinguish between non-degrading offsets and degrading offsets; for the degrading offsets, supplementary sampling under the same operating condition is triggered, and state advancement is performed based on the supplementary sampling results to update the state memory anchor point corresponding to the current operating condition; the state monitoring results of the target grounding object are output.

[0007] Furthermore, establishing the state memory anchor point includes: setting an effective anchor point and an isolation anchor point for the same operating condition; when a newly acquired trusted data segment deviates from the effective anchor point corresponding to the current operating condition, the trusted data segment is written to the isolation anchor point, and the effective anchor point is not updated; when the deviation is determined to be a non-degenerate deviation by prioritizing evidence of contradiction and meets the preset stability condition, or meets the preset migration condition after supplementary sampling under the same operating condition, the effective anchor point is updated with the isolation anchor point.

[0008] Furthermore, for the offset, acquisition distortion counter-evidence flags, co-interference counter-evidence flags, and operating condition induced counter-evidence flags are generated respectively, and judged in sequence according to preset rejection priority; when any counter-evidence flag is valid during the judgment process, a rejection lock flag is set for the offset, and the degradation offset judgment and state advancement are terminated; when all counter-evidence flags are invalid, the offset is judged as a degradation offset, and the same operating condition supplementary sampling is triggered.

[0009] Furthermore, the supplementary sampling under the same working condition includes: after the target grounding object re-enters the working condition corresponding to the offset, collecting boundary verification segments and stability verification segments respectively; when the boundary verification segments and the stability verification segments maintain the same offset direction relative to the state memory anchor point corresponding to the current working condition, state advancement is performed; otherwise, the current round of state advancement is terminated.

[0010] Furthermore, an offset direction identifier is attached to the trusted data segment corresponding to the offset, and trusted data segments with the same offset direction relative to the effective anchor point are written into the same isolation anchor point; when the offset direction of the newly acquired trusted data segment is inconsistent with the offset direction of the data segment already written in the isolation anchor point, the isolation anchor point is reconstructed.

[0011] Furthermore, after updating the effective anchor point with the isolation anchor point, a freeze period is set for the updated effective anchor point; during the freeze period, even if the newly acquired trusted data fragment is offset relative to the updated effective anchor point, it is still only written to the corresponding isolation anchor point, and the effective anchor point is not triggered to be updated again.

[0012] Furthermore, the acquisition distortion counter-evidence flag, the co-interference counter-evidence flag, and the operating condition induced counter-evidence flag are constructed into an irreversible priority chain; when the preceding counter-evidence flag is established, the judgment result of the following counter-evidence flag is blocked, and the subsequent counter-evidence flag is prohibited from changing the judgment conclusion corresponding to the preceding counter-evidence flag.

[0013] Furthermore, the rejection lock flag is associated with the current operating condition corresponding to the offset and the offset direction; during the effective period of the rejection lock flag, for subsequent offsets that enter the current operating condition and have the same offset direction, the degradation offset determination and state advancement are directly terminated until the operating condition change or offset direction reversal is detected and the rejection lock flag is released.

[0014] Furthermore, a transition constraint segment is extracted between the boundary verification segment and the stability verification segment; when the transition constraint segment does not flip in the opposite direction to the offset direction relative to the state memory anchor point corresponding to the current working condition, the state advancement is executed; otherwise, the current round of state advancement is determined to be a working condition switching disturbance and terminated.

[0015] Furthermore, the transition constraint segment is divided into multiple continuous sub-segments, and the offset direction of each continuous sub-segment relative to the state memory anchor point corresponding to the current working condition is determined. When the direction changes alternately between adjacent continuous sub-segments, an oscillation flag is generated, and the current state advancement is determined to be a working condition switching disturbance and terminated. When the offset directions of the multiple continuous sub-segments are all consistent with the offset direction, the state advancement is executed.

[0016] Compared with existing technologies, the present invention first segments the continuous monitoring data according to the working conditions, and then filters out reliable data segments based on the acquisition status. Then, it establishes a status memory anchor point with historical reliable data under the same working conditions. This allows the comparison benchmark to be limited to comparable conditions, which helps to reduce the interference of working condition changes and sampling anomalies on status judgment.

[0017] This invention employs a counter-evidence priority review mechanism for offsets, and only triggers supplementary sampling and state advancement under the same operating conditions after an offset is identified as degenerative. This distinguishes between offsets caused by acquisition distortion, interference factors, and operating conditions, and genuine degenerative offsets, thereby reducing misjudgments and reference drift. Furthermore, through the settings of effective anchor points, isolation anchor points, veto locks, and freeze periods, state updates can be made gradual and constrained, making it more suitable for continuous tracking of the degradation process of grounded objects in long-term online monitoring scenarios. Attached Figure Description

[0018] Figure 1 This is a flowchart of the grounding resistance state determination and state progression process of the present invention.

[0019] Figure 2 This is a flowchart illustrating the collaborative establishment and updating of the state memory anchor point dual anchor point in this invention.

[0020] Figure 3 This is a flowchart illustrating the priority review and rejection process for counter-evidence regarding the degenerative shift of this invention.

[0021] Figure 4 This is a flowchart of the supplementary sampling and state progression determination process for the same working conditions in this invention. Detailed Implementation

[0022] Combined with appendix Figure 1 As shown, in a specific implementation, the following steps are first taken: acquiring continuous monitoring data of the grounding resistance of the target grounding object, operating condition information, and acquisition status information. The continuous monitoring data characterizes the resistance change of the target grounding object over a continuous time axis. The operating condition information characterizes the operating environment and conditions of the target grounding object. The acquisition status information characterizes the validity and completeness of the current monitoring data during the acquisition process. Operating condition information may include load status, equipment operating mode, ambient humidity, ambient temperature, soil condition, electrical disturbance intensity, or other data that can affect grounding resistance performance. Acquisition status information may include the continuity of acquisition time, sensor online status, signal stability, communication quality, and anomaly reporting information. Simultaneously acquiring these three types of information provides fundamental data support for subsequently distinguishing differences in operating conditions, identifying the source of anomalies, and determining the authenticity of status changes.

[0023] After obtaining the raw data, the continuous monitoring data of grounding resistance is segmented according to the operating condition information to obtain data segments whose operating condition parameters fall within the same preset range. In other words, continuous monitoring data generated under the same or similar operating conditions are divided into similar segments to avoid comparison distortion caused by mixing different operating conditions. The preset range can be set according to a single operating condition parameter or a combination of multiple operating condition parameters, thus ensuring that the operating conditions within the same data segment remain basically consistent. After segmentation, the data segments are then filtered according to the acquisition status information, removing data segments with missing acquisitions, sensor anomalies, signal jumps, communication interruptions, or significant distortions, retaining reliable data segments that meet preset reliability conditions. This step ensures higher consistency and reliability of the data subsequently used for status judgment, reducing misjudgments from the source.

[0024] Furthermore, state memory anchors are established based on historical reliable data segments according to operating conditions. These state memory anchors characterize the reference state of grounding resistance under the corresponding operating condition. That is, different operating conditions correspond to different state memory anchors, each formed from long-term accumulated reliable data segments under that condition, reflecting the normal reference level of the target grounding object under that condition. State memory anchors can be composed of representative feature values ​​from historical reliable data segments, or multiple statistical features, as long as they can stably characterize the reference state of grounding resistance under that condition. When a newly acquired reliable data segment arrives, it is compared with the state memory anchor corresponding to the current operating condition to obtain the difference between the two. When the difference exceeds a preset offset threshold, it is determined that the current grounding resistance has shifted relative to the reference state under that operating condition, and the offset direction is determined based on the direction of change of the difference. The offset direction can be reflected as an increasing or decreasing trend relative to the state memory anchor. By comparing under the same operating condition, rather than directly comparing globally, the interference of operating condition changes on the grounding resistance judgment results can be effectively reduced.

[0025] After identifying an offset, it is not directly classified as a degradation of the target grounding object. Instead, a prioritization review of the counter-evidence is performed to distinguish between non-degradable and degradable offsets. This prioritization review means that the current offset is checked from the perspective of non-degradation causes to determine whether it is caused by abnormal acquisition, external interference, short-term operating condition fluctuations, or other non-degradation factors. If the review confirms that the offset originates from a non-degradation factor, it is classified as a non-degradable offset, and no state update is triggered. If no counter-evidence sufficient to refute the degradation judgment is found, it is classified as a degradable offset. For degradable offsets, supplementary sampling under the same operating condition is triggered. That is, after the target grounding object re-enters the operating condition corresponding to the current offset, new reliable data segments are collected to verify whether the offset has the characteristics of recurrence and persistence. If the supplementary sampling results show that the offset remains consistent under the same operating condition, state advancement is performed to update the state memory anchor point corresponding to the current operating condition, so that the updated state memory anchor point reflects the latest true state of the target grounding object. If the supplementary sampling results fail to prove the stable existence of the offset again, the original state memory anchor point remains unchanged.

[0026] Combined with appendix Figure 2As shown in the specific implementation, the establishment and updating of state memory anchors adopts a dual-anchor collaborative mechanism. Under the same operating condition, effective anchors and isolation anchors are set separately. The effective anchor is used to represent the baseline state that has been confirmed to be effective under the current operating condition, while the isolation anchor is used to carry the data set that is still in the observation, verification, or migration stage. Based on historical reliable data fragments, the initial effective anchors under the corresponding operating condition are formed first to serve as the reference basis for subsequent state comparisons. When a newly acquired reliable data fragment deviates from the effective anchor corresponding to the current operating condition, the effective anchor is not directly updated with the reliable data fragment. Instead, the reliable data fragment is written to the corresponding isolation anchor, so that the data after the deviation first enters the isolation observation state. By setting the effective anchor and the isolation anchor separately, the confirmed stable baseline state and the deviation state to be verified can be isolated from each other, avoiding short-term anomalies, occasional disturbances, or unconfirmed changes from directly overwriting the original baseline state, thereby improving the robustness and update accuracy of state monitoring. When an offset is determined to be a non-degradable offset through prioritization of counter-evidence and meets the preset stability conditions, it indicates that although the offset does not represent a degradative behavior of the target grounding object, it has already formed a stable new performance state under the current operating conditions. At this point, the data characteristics carried in the isolation anchor point can be migrated to the formal reference. Alternatively, when the offset meets the preset migration conditions after supplementary sampling under the same operating conditions, it indicates that the offset has been repeatedly verified under the same operating conditions and has persistence. In this case, the effective anchor point is also updated with the isolation anchor point, so that the state memory anchor point under the current operating conditions completes the controlled state advancement.

[0027] Furthermore, to improve the consistency and discriminability of data within isolation anchors, an offset direction identifier is added to the trusted data segments corresponding to the offset. The offset direction identifier indicates whether the trusted data segment offsets in an increasing or decreasing direction relative to the effective anchor. During the writing process of isolation anchors, only trusted data segments with the same offset direction relative to the effective anchor are written to the same isolation anchor to ensure that the data segments gathered in the same isolation anchor maintain a consistent trend of change. With this setting, the isolation anchor no longer simply stores offset data but is used to represent candidate states in a specific direction. When the offset direction of a newly acquired trusted data segment is inconsistent with the offset direction of the data segments already written to the isolation anchor, it indicates that the current offset trend conflicts with the observed candidate state trend, and the original isolation anchor is no longer suitable to continue carrying out the new offset process; therefore, the isolation anchor is rebuilt. Reconstruction can manifest as clearing the data segments already stored in the original isolation anchor, or re-establishing an isolation anchor using the newly acquired trusted data segment as a new isolation starting point.

[0028] After updating the effective anchor point with an isolation anchor point, a freeze period is set for the updated effective anchor point. The freeze period is limited to a preset time range or a preset sampling period immediately after the state transition, temporarily preventing newly occurring offsets from immediately pushing for another update of the effective anchor point. During the freeze period, even if a newly acquired trusted data segment offsets again relative to the updated effective anchor point, the trusted data segment is only written to the corresponding isolation anchor point, without triggering another update of the effective anchor point. In other words, new offsets are allowed to continue to be monitored and recorded during the freeze period, but continuous jumps in the baseline state are not permitted. This effectively avoids frequent migrations of the effective anchor point in the early stages of the transition between old and new states due to short-term fluctuations, boundary disturbances, or transitional instability, preventing the state memory anchor point from swinging back and forth and being repeatedly overwritten. After the freeze period ends, the process of normal offset identification, priority review of counter-evidence, and supplementary sampling verification is followed to determine whether to perform the next round of updates for the effective anchor point corresponding to the current operating condition.

[0029] Combined with appendix Figure 3 As shown, in a specific implementation, when a newly acquired reliable data segment deviates from the effective anchor point corresponding to the current operating condition, the deviation is not immediately identified as a degradation of the target grounding object. Instead, a prioritization review of the deviation is performed. This prioritization review is used to investigate the causes of the deviation step-by-step, starting from non-degradation sources. Specifically, a data acquisition distortion deviation flag, a common disturbance deviation flag, and an operating condition-induced deviation flag are generated for each deviation, and they are judged sequentially according to a preset rejection priority. The data acquisition distortion deviation flag indicates whether the current deviation is caused by sensor anomalies, missing sampling, communication fluctuations, signal jumps, or data distortion. The common disturbance deviation flag indicates whether the current deviation is caused by an external common disturbance source, which may include synchronous interference in the grounding network, sudden changes in the electromagnetic environment, simultaneous switching of associated equipment, or other factors that are not related to changes in the target grounding object itself. The operating condition-induced deviation flag indicates whether the current deviation is induced by changes in the operating condition boundary, transitional disturbances in the operating condition, or short-term drift of operating condition parameters. By sequentially judging the aforementioned counter-evidence flags, offset sources unrelated to the degradation of the target grounding object can be prioritized for elimination. When any counter-evidence flag is valid during the judgment process, the current offset is considered to have a clear non-degradational interpretation path. At this time, a rejection lock flag is set for the offset, and the degradation offset judgment and state advancement are terminated, thereby preventing non-true degradation offsets from entering the subsequent state transition process. When all counter-evidence flags are invalid, it means that no counter-evidence sufficient to negate the degradation judgment has been found for the current offset. In this case, the offset is judged as a degradation offset, and supplementary sampling under the same operating conditions is triggered to re-verify the degradation offset under the same operating conditions.

[0030] Furthermore, to ensure a stable logical order and clear veto power in the disproving process, the acquisition distortion disproving flag, the co-interference disproving flag, and the condition-induced disproving flag are constructed into an irreversible priority chain. In this priority chain, the judgment conclusion of a preceding disproving flag takes precedence over that of a subsequent disproving flag. When a preceding disproving flag is valid, the judgment result of a subsequent disproving flag is blocked, and subsequent disproving flags are prohibited from altering the judgment conclusion corresponding to a preceding disproving flag. In other words, once a higher-priority review stage has confirmed that the current offset is due to acquisition distortion or other preceding non-degradation factors, subsequent review stages, even if they detect other phenomena, cannot overturn the already established preceding veto conclusion. This irreversible priority chain structure avoids repeated interpretations or cross-judgments of the same offset across multiple disproving channels, reduces judgment oscillations, and improves the consistency and repeatability of the degradation identification process. Preferably, the rejection priority can be set such that evidence of data collection distortion takes precedence over evidence of co-interference, and evidence of co-interference takes precedence over evidence of working condition-induced distortion, so that the factors that most directly affect the authenticity of the data are reviewed first, thereby ensuring that the judgment of degradation bias is based on credible data.

[0031] Building upon the above, the rejection lock flag is associated with the current operating condition and offset direction corresponding to the offset. In other words, the rejection lock flag does not exist in isolation but is bound to a specific operating condition and a specific offset direction within that condition. With this setting, during the validity period of the rejection lock flag, for subsequent offsets that re-enter the current operating condition with the same offset direction, the degradation offset determination and state advancement can be directly terminated without repeating the complete degradation identification process. This avoids the system repeatedly consuming computational resources on the same type of rejected offset pattern and reduces repeated misjudgments caused by recurring homogeneous disturbances. The rejection lock flag is not permanently valid but is released when a change in operating condition or a reversal of offset direction is detected. A change in operating condition refers to the target grounding object entering a different operating condition range than the one currently locked. A reversal of offset direction refers to the subsequent trusted data segment changing in the opposite direction to the original locked offset direction relative to the effective anchor point. If any of the above situations occur, it indicates that the conditions on which the original veto lock depended have changed. The system will regain its normal ability to determine the new offset and will re-execute the evidence-of-contrast priority review, degradation identification and state advancement process.

[0032] Combined with appendix Figure 4As shown, in a specific implementation, for cases determined to be degenerate offsets after priority review of counter-evidence, the state memory anchor point corresponding to the current operating condition is not immediately updated. Instead, supplementary sampling under the same operating condition is performed to confirm whether the offset has the characteristics of recurrence and persistence. Supplementary sampling under the same operating condition includes collecting boundary verification segments and stability verification segments after the target grounding object re-enters the operating condition corresponding to the offset. The boundary verification segment is used to characterize the initial response state of the target grounding object immediately after entering the corresponding operating condition, and the stability verification segment is used to characterize the stable response state of the target grounding object after maintaining the operating condition for a period of time. By acquiring the above two verification segments simultaneously, the persistence of the offset at the operating condition entry boundary and the stable operating condition phase can be examined separately. When both the boundary verification segment and the stability verification segment maintain the same offset direction relative to the state memory anchor point corresponding to the current operating condition, it indicates that the offset does not only appear briefly at the moment of operating condition entry, nor does it only appear sporadically in a local phase, but has a continuous and consistent trend of change under the same operating condition. At this time, state advancement is performed. If either the boundary verification segment or the stability verification segment fails to maintain the same offset direction as the original offset, it indicates that the offset lacks sufficient consistency and continuity and cannot be used as the basis for state transition. Therefore, the current round of state advancement is terminated to keep the state memory anchor point corresponding to the current working condition unchanged.

[0033] Furthermore, to avoid misjudging short-term disturbances generated by the target grounding object during condition switching as stable degradation, a transition constraint segment is extracted between the boundary verification segment and the stability verification segment. The transition constraint segment characterizes the intermediate evolution of the target grounding object from entering the corresponding condition to reaching a stable condition. By analyzing the trajectory of this transition phase, it can be determined whether the aforementioned offset maintains a consistent direction throughout the entire condition transition process. When the transition constraint segment does not exhibit a directional flip opposite to the offset direction relative to the state memory anchor point corresponding to the current condition, it indicates that the offset has not undergone a reverse change throughout the entire boundary entry, transition evolution, and stability maintenance process, proving that this round of offset has good continuity and consistency; therefore, state advancement is executed. If a directional flip opposite to the offset direction is detected in the transition constraint segment relative to the state memory anchor point corresponding to the current condition, it indicates that the current offset has a significant unstable process during the condition transition phase. This offset is more likely to originate from disturbances caused by condition switching rather than a continuous change in the actual state of the target grounding object; therefore, this round of state advancement is judged as a condition switching disturbance and terminated.

[0034] To further improve the accuracy of identifying disturbances during the transition phase, the transition constraint segment is divided into multiple continuous sub-segments, and the offset direction of each continuous sub-segment relative to the state memory anchor point corresponding to the current operating condition is determined. These continuous sub-segments can be arranged sequentially in chronological order and together constitute a complete transition process from the boundary verification segment to the stable verification segment. By determining the offset direction segment by segment, the changing trend of the offset during the transition process can be observed in more detail. When alternating changes in direction occur between adjacent continuous sub-segments, it indicates that there is an alternating fluctuation in positive and negative directions during the transition process. At this time, an oscillation flag is generated, and the current round of state advancement is determined to be a condition switching disturbance and terminated. The oscillation flag is used to characterize that the offset does not have a unidirectional continuous evolution characteristic during the transition phase, but rather fluctuates back and forth due to the influence of the switching boundary or short-term disturbances. Conversely, when the offset directions of multiple continuous sub-segments are all consistent with the offset direction, it indicates that the offset direction remains unified during the transition process, without back-and-forth flipping or local reverse disturbances. This further proves that the offset has repeatability and stability under the same operating condition, and therefore state advancement is executed.

[0035] Example 1: In this embodiment, the target grounding object is the monitored grounding point in the substation grounding network. The monitoring system continuously collects grounding resistance monitoring data, operating condition information, and acquisition status information, and performs status monitoring in the controller. The operating condition information is used to characterize the operating background related to changes in grounding resistance, and includes at least one or more of the following: load range, ambient temperature range, soil moisture range, or equipment operation phase. The acquisition status information is used to characterize whether the acquisition process meets the reliability conditions, and includes at least one or more of the following: sensor online status, sampling clock synchronization status, signal integrity status, and communication integrity status. The controller first divides the continuous monitoring data into data segments falling within the same preset operating condition range based on the operating condition information, and then removes data segments corresponding to out-of-synchronization, missing samples, sudden jumps, and saturation based on the acquisition status information to obtain reliable data segments for subsequent anchor point establishment and status determination.

[0036] Because continuous monitoring data is directly affected by instantaneous disturbances, sampling discreteness, and short-term fluctuations, directly comparing single-point sampled values ​​with historical benchmarks can easily misidentify transient noise as state changes. This embodiment first compresses reliable data segments under the same operating condition into segment-representative resistance values, and then compares these segment-representative resistance values ​​with anchor points. This transforms the comparison object from a single sampling point into a segment-level statistic, thereby reducing the impact of occasional sampling fluctuations on the judgment results. (In operating condition category...) Under the conditions, the first A reliable data segment represents a resistance value defined as follows: In the formula, Indicates working conditions Next The representative resistance value of a reliable data segment, which is the segment's representative resistance value used for comparison with the anchor point; This indicates the first [number] data segment within the trusted data segment. The measured grounding resistance values ​​at each sampling point are obtained from continuous grounding resistance monitoring data. Indicates the sampling point number within the segment; Indicates the first The number of valid sampling points within a reliable data segment is derived from the number of remaining sampling points after filtering the acquisition status information. Indicates the first The reliability weight of each sampling point is derived from the acquisition status information corresponding to that sampling point, and can be preset according to the degree of time synchronization, signal integrity, and sampling stability. After adopting this formula, a data segment under the same operating condition is compressed into a single segment representing the resistance value, and subsequent anchor point comparison, offset direction identification, and migration criteria all use the resistance value represented by this segment as input.

[0037] Under the same operating condition, the controller sets an effective anchor point and an isolation anchor point. The effective anchor point characterizes the current baseline state accepted by the system, serving as a comparison benchmark for real-time judgment. The isolation anchor point is used to temporarily store reliable data segments that deviate from the effective anchor point, so as to observe whether the deviation is persistent and unidirectional later. For each operating condition... The system maintains a unique effective anchor point. With the current effective isolation anchor points .in, The initial value can be determined by the centralized statistical results of the resistance values ​​represented by historical reliable data segments under this operating condition. The initial stage is empty. When the newly acquired reliable data fragment belongs to the operating condition... At that time, the system first uses this segment to represent the resistance value and... In comparison, the isolation anchor is only written after an offset is confirmed, and no changes are made at this point. .

[0038] To determine whether a new segment deviates from the current baseline state and to provide a unified criterion for subsequent isolation writes and migration updates, this embodiment employs a joint expression for offset and migration determination. In the formula, Indicates working conditions Next The offset of a trusted data segment relative to the currently active anchor point is determined by the resistance value represented by the segment. With effective anchor value The difference; Indicates working conditions The currently active state memory anchor value; Indicates the offset direction; For a sign function, when Output positive offset when Output reverse offset when Output zero offset; This indicates the number of consecutively written to the same isolation anchor point. A trusted data segment number; This indicates the number of trusted data segments that have been written consecutively within the same isolation anchor point and have the same offset direction. Indicates working conditions The migration amplitude threshold below; Indicates working conditions The minimum number of stable holding times threshold is used. The first two parts of the formula are used to calculate the offset and determine the offset direction, and the last part is used to determine whether the same-direction offset in the isolation anchor point has reached the migration condition. The logic of this formula is that the segment representative resistance value reflects the single segment state, the offset reflects its distance relative to the reference, the average offset amplitude of continuous same-direction offset segments reflects whether the offset is continuous, and the segment number threshold reflects whether the offset has reached the degree of stable holding. When both are satisfied, it means that the offset has the basis to transition from the temporary state to the new reference state.

[0039] when When the absolute value exceeds the preset offset threshold, the system determines that the first... A reliable data segment relative to the operating condition The effective anchor point has shifted, and This offset direction identifier is appended to the trusted data segment. If the current operating condition... If no isolation anchor point has been established, then establish an isolation anchor point starting with this segment and record the corresponding offset direction. If the current operating condition... An isolation anchor point already exists, and the new fragment's If the offset direction is consistent with that already recorded in the isolation anchor, then the fragment is written to the same isolation anchor to accumulate evidence of offset in the same direction. If the new fragment's... If the offset direction is inconsistent with that recorded in the isolation anchor point, it is determined that the offset trend represented by the original isolation anchor point has been destroyed. The system reconstructs the isolation anchor point and uses the new segment as the first segment of the new isolation anchor point. Through this processing method, the isolation anchor point only retains data segments that are continuously offset in the same direction relative to the effective anchor point under the same operating condition, which can prevent alternating fluctuations in positive and negative directions from participating in the migration judgment.

[0040] The anchor value of an isolation anchor point can be progressively aggregated from the resistance values ​​represented by trusted data segments already written to that anchor point. This update process does not affect the external judgment function of the active anchor point. After each new segment is written to the isolation anchor point, the controller updates the value based on the number of consecutive same-direction offset segments within that anchor point. And the average offset of these segments relative to the effective anchor point, to determine whether the aforementioned migration conditions are met. When Not yet reached Or the average offset amplitude has not yet reached At this time, the system maintains the effective anchor point unchanged and continues to observe subsequent data segments under the same operating conditions. This processing ensures that a single abnormal sampling or short-term drift only stays in the isolation layer and does not directly rewrite the baseline state, thereby improving the anti-interference capability of state memory.

[0041] When the same-direction offset segments within the isolation anchor point continue to accumulate and meet the stability or migration conditions, the system updates the operating condition with the current isolation anchor point. The effective anchor point. The stability condition can be achieved by continuously offsetting segments in the same direction to reach the minimum number of hold-ups. To characterize this, the migration condition can be defined as the average offset amplitude of consecutive unidirectional offset segments reaching a threshold. This is used to characterize the state. When both work together, it indicates that the new state has demonstrated sufficient persistence and amplitude consistency relative to the historical baseline, meeting the conditions for entering the new baseline state. After the update is completed, the effective anchor point before the update becomes invalid, and the updated anchor point becomes the new one. Participate in subsequent working conditions Real-time comparison and judgment.

[0042] After the effective anchor point is updated, the system will update the anchor point. Set a freeze period. The freeze period starts when the effective anchor point update is completed, and its duration can be preset according to the operating condition type. During the freeze period, even if the newly acquired trusted data fragment is relative to the updated... If an offset occurs again, the system will still only write the fragment to the corresponding isolation anchor point in the offset direction, without triggering any further actions. The system updates again. This mechanism is used to suppress short-term oscillations after anchor point updates, sampling recovery fluctuations, and frequent back-and-forth updates caused by residual disturbances within the operating condition, ensuring that the newly effective anchor point remains stable for a period of observation. After the freeze period expires, the system resumes the normal migration judgment process and re-executes isolation accumulation and migration judgment for subsequent offsets.

[0043] For ease of explanation, this embodiment presents a set of numerical processes. Under operating conditions... Below, the initial effective anchor point for The three newly acquired reliable data fragments represent resistance values ​​as follows: , and Based on the aforementioned offset expression, the offsets of the three segments are as follows: , and The offset directions are all positive. If this operating condition is set... , If all three conditions are met—the number of consecutive times they are held in the same direction and the average offset amplitude—the system updates the effective anchor point based on this, using the isolated anchor point. The updated new... The aggregated result representing the resistance value of the segment within the isolated anchor point can be taken, for example... Then it enters a freeze period. If a segment appears during the freeze period, it represents a resistance value of For trusted data fragments, the system only writes them to the corresponding isolated anchor point, instead of immediately changing the effective anchor point. Update to a higher value to avoid continuously rewriting the baseline state in a short period of time.

[0044] Example 2: In this embodiment, the target grounding object is the grounding grid or independent grounding electrode in the power system. The monitoring device continuously acquires grounding resistance monitoring data, operating condition information, and acquisition status information, and performs status monitoring within the control unit. The operating condition information characterizes the operating background of the grounding object, including at least one of the following: load range, ambient temperature range, soil moisture range, and equipment operation stage. The acquisition status information characterizes whether the current sampling process meets the reliability conditions, including at least one of the following: sensor online status, clock synchronization status, signal integrity status, and communication integrity status. The control unit first divides the continuous monitoring data into data segments whose operating condition parameters fall within the same preset range based on the operating condition information, and then removes data segments corresponding to missing samples, sudden jumps, saturation, and timing anomalies based on the acquisition status information to obtain reliable data segments. The newly acquired reliable data segments are then compared with the state memory anchor point corresponding to the current operating condition to form the current offset and its offset direction.

[0045] The state memory anchor point is used to characterize the reference state of the grounding resistance under the current operating conditions, denoted as . .in, This indicates the current operating condition category, used to distinguish monitoring environments under different load, temperature, or humidity ranges. After extracting the representative resistance value from the newly acquired reliable data segment, the representative resistance value of the segment to be judged is formed, denoted as... Superscript symbol This indicates that the initial offset segment that triggered this round of review is not the zero point in time. The control unit will... With anchor point The offset is obtained through comparison, and its direction is determined by its sign. The offset direction is used for subsequent priority review of counter-evidence, rejection locking, supplementary sampling under the same working condition, and state progression determination. At this point, the system completes the transformation from continuous sampled values ​​to determineable offset events, making the subsequent judgment objects uniformly the segment-level offsets corresponding to the working condition, rather than single-point fluctuations.

[0046] For offsets, the system first performs a priority review of counter-evidence before deciding whether to proceed to the degradation offset judgment. The priority review of counter-evidence generates at least three counter-evidence flags: acquisition distortion counter-evidence flag, common disturbance counter-evidence flag, and operating condition-induced counter-evidence flag. The acquisition distortion counter-evidence flag indicates whether the current offset originates from sensor mismatch, timing misalignment, message loss, or signal distortion. The common disturbance counter-evidence flag indicates whether the current offset occurs synchronously with an external common disturbance source, including common electromagnetic interference, disturbance on the same bus, or transient environmental changes in the same area. The operating condition-induced counter-evidence flag indicates whether the offset is induced by the operating condition switching boundary itself. The three types of counter-evidence flags are judged sequentially according to a preset rejection priority and constructed into an irreversible priority chain. In this embodiment, the priority chain can be set so that acquisition distortion counter-evidence takes precedence over common disturbance counter-evidence, and common disturbance counter-evidence takes precedence over operating condition-induced counter-evidence. When a higher-priority counter-evidence is established, subsequent counter-evidence results are masked, and subsequent counter-evidence conclusions are prohibited from changing previous counter-evidence conclusions.

[0047] When any counter-evidence flag is valid, the control unit sets a rejection lock flag for the current offset and terminates the current round of degenerate offset determination and state progression. The rejection lock flag is related to the current operating condition. And the current offset direction is associated with the storage. During the lock's effective period, subsequent entry into the same operating condition will not be possible. Furthermore, for offset events whose offset direction is consistent with the locked direction, there is no need to repeat the degenerate offset judgment; the state progression can be directly terminated. Through this processing, the system treats offsets in the same working condition and direction that have been rejected by previous reviews as the same type of event, thereby reducing the burden of repeated reviews. The rejection lock flag is released when a change in working condition or a reversal of offset direction is detected. This is because a change in working condition means that the comparison scenario has changed, and a reversal of direction means that the physical orientation of the current offset event has changed, and continuing to use the original lock conclusion would lose its basis.

[0048] When all counter-evidence flags are invalid, the control unit determines the current offset as a degenerate offset to be verified and triggers supplementary sampling under the same operating condition. Supplementary sampling does not extend the comparison outside the current operating condition; instead, it continues to collect data segments for verification after the target grounding object re-enters the same operating condition corresponding to the offset. Supplementary sampling includes at least a boundary verification segment, a stability verification segment, and a transition constraint segment between the two. The boundary verification segment observes whether the offset direction can continue the initial offset direction when the target object re-enters the vicinity of the boundary of the same operating condition. The stability verification segment observes whether the offset direction remains consistent after a short period of stabilization. The transition constraint segment constrains the continuous evolution process between the boundary verification segment and the stability verification segment, preventing the misinterpretation of intermediate flips or oscillations as stable degradation based solely on consistency at both ends.

[0049] To transform the relationship between the initial offset direction and the directions of each supplemented sample segment into a unified criterion, this embodiment adopts the following direction consistency expression. In the formula, Indicates the current operating condition The initial offset fragment relative to the state memory anchor point The offset is derived from the resistance value represented by the current trusted data segment. With anchor value The difference; Indicates the initial offset direction; For a sign function, when When the value is greater than zero, the output is positively offset. Output reverse offset when less than zero; This indicates that the boundary verification fragment is relative to the same anchor point. The offset direction originates from the boundary verification segment representing the resistance value and The comparison results; Indicates a stable verification fragment relative to The offset direction originates from the resistance value represented by the stable verification segment and... The comparison results; This indicates the first segment after the transition constraint segment is partitioned. A continuous sub-segment relative to The direction of offset; Indicates the number of consecutive sub-segments; This represents the total number of consecutive sub-segments obtained by dividing the transition constraint segment; This is an indicator function that takes the value when its internal condition is true. If not true, the value is taken as ; This indicates the degree to which the initial offset direction is maintained during the supplementary sampling under the same operating condition. The purpose of this formula is to uniformly convert the consistency of the boundary verification segment, the stable verification segment, and all continuous sub-segments with the initial offset into a single retention index. The logic behind this formula is that if the offset is a true degradation, its direction should remain consistent throughout the boundary position, stable position, and intermediate transition process after re-entering the same operating condition; if the offset originates from operating condition switching disturbances or acquisition distortion, the direction is unlikely to remain consistent throughout the entire process. The boundary verification segment and the stable verification segment participate in the calculation because the boundary segment reflects the continuity in the initial stage of entering the same operating condition, while the stable segment reflects the continuity after the operating condition stabilizes; the absence of either will render the degradation judgment incomplete. The transition constraint segment continues to participate in the calculation to incorporate the change process between the beginning and end into the constraints, avoiding the omission of mid-way reversal information. For this embodiment, This indicates that the boundary verification segment, the stable verification segment, and all consecutive sub-segments are aligned with the initial offset direction, constituting one of the necessary conditions for execution state advancement; when If this occurs, it indicates that at least one verification position or transition position is inconsistent with the initial direction, and the current state advancement should be terminated.

[0050] The retention rate determination alone is insufficient to identify the alternation of directions during the transition process. Therefore, this embodiment further introduces expressions for identifying direction reversal and oscillation. In the formula, This indicates the number of orientation flips between adjacent consecutive sub-segments within a transition constraint segment; and They represent the first The and the first A continuous sub-segment relative to the anchor point The offset direction; when two adjacent consecutive sub-segments have different directions, the indicator function takes the value of This indicates that a direction flip has occurred; Indicates working conditions The oscillation determination threshold is used to determine how many directional alternations are needed to generate an oscillation identifier. The purpose of this formula is to explicitly statistically identify the directional alternation behavior implicit in the transition constraint segment.

[0051] The derivation logic is that true degradation, after regression to the same operating condition, should maintain a continuous direction. Even if there are amplitude fluctuations during the transition process, there should be no repeated alternation of directions. If adjacent sub-segments within the transition interval experience multiple direction switches, it better matches the characteristics of operating condition switching disturbances or boundary oscillations. The introduction of continuous sub-segments is used to improve observation resolution and avoid compressing the entire transition interval into a single segment representing the resistance value, thus masking local flips. In this embodiment, when When this happens, the system generates an oscillation flag and terminates the current state progression as a condition switching disturbance; when and If the transition interval does not show a direction reversal and all verification segments are consistent with the initial offset direction, then state advancement can proceed.

[0052] Based on the above two criteria, the control unit makes a comprehensive judgment according to the following rules during the supplementary sampling phase under the same operating conditions. If either the boundary verification segment or the stability verification segment deviates from the initial offset direction, then... Less than The current state progression terminates. If the boundary verification segment and the stability verification segment are aligned with the initial offset direction, but the transition constraint segment contains consecutive sub-segments with the opposite initial offset direction, then... Also less than The current state progression terminates. If the transition constraint segment further exhibits directional alternation between adjacent consecutive sub-segments, then... Reaching or exceeding the threshold An oscillation flag is generated, and the current state advancement is determined to be a condition switching disturbance and terminated. The control unit only confirms the offset as an advanceable state and executes state advancement when the offset direction of the boundary verification segment, the stability verification segment, and each continuous sub-segment is consistent with the initial offset direction, and there is no direction reversal or direction alternation in the transition interval.

[0053] To illustrate the oscillation identification process, let the current operating condition be... Initial offset direction The direction is positive. Upon re-entering this condition, the boundary verification segment direction is positive, the stability verification segment direction is positive, and the transition constraint segment is divided into four continuous sub-segments with the direction sequence being positive, positive, negative, and positive. According to the aforementioned preservation expression, since the direction of the third continuous sub-segment is positive... Inconsistent Less than According to the direction reversal expression, direction changes occur between the second and third consecutive sub-segments, and between the third and fourth consecutive sub-segments. At least for .exist Pick In this case, the system generates an oscillation flag and terminates the state progression of that round as a condition switching disturbance. If all four consecutive sub-segments are in the positive direction, then... and The system then proceeds according to the status.

[0054] Through the above implementation methods, after detecting an offset, the system first performs a rebuttal-priority review before deciding whether to proceed to degenerative offset verification, reducing the risk of misjudging data acquisition distortion, interference events, and condition-induced fluctuations as degradation. Through an irreversible priority chain, once a higher-priority rejection conclusion is formed, it will not be overturned by subsequent conclusions, ensuring the unidirectional stability of the review results. By using a rejection lockout identifier, rejected offsets in the same direction under the same operating condition are included in lockout management, reducing redundant reviews. Through a combination of boundary verification segments, stability verification segments, and transition constraint segments, the initial state, steady-state maintenance, and intermediate transition process after re-entering the same operating condition are simultaneously included in the review. By alternating the direction of continuous sub-segments to identify oscillations, transitional oscillations are further avoided from being misjudged as stable degradation. Finally, the control unit outputs the status monitoring results of the target grounding object, which can be characterized as at least one of the following: rebuttal rejection, lockout termination, pending supplementary sampling, oscillation termination, or state progression completion, thereby improving the accuracy and engineering usability of grounding resistance status monitoring.

Claims

1. A method for monitoring the state of grounding resistance, characterized in that, include: Acquire continuous monitoring data of the grounding resistance, operating conditions, and acquisition status of the target grounding object; The continuous monitoring data is segmented according to the operating condition information to obtain data segments whose operating condition parameters fall within the same preset range; the data segments are then filtered according to the acquisition status information to obtain reliable data segments that meet preset reliability conditions. State memory anchors are established based on historical reliable data segments according to operating conditions. The state memory anchors are used to characterize the reference state of grounding resistance under the corresponding operating conditions. The newly acquired reliable data segments are compared with the state memory anchors corresponding to the current operating conditions. When the comparison difference exceeds the preset offset threshold, it is determined that an offset has occurred and the offset direction is determined. The occurrence of offsets is subject to priority review for evidence of dissent in order to distinguish between non-degenerate offsets and degenerate offsets; The degradation offset triggers supplementary sampling under the same operating condition, and state advancement is performed based on the supplementary sampling results to update the state memory anchor point corresponding to the current operating condition; Output the status monitoring results of the target grounded object.

2. The method for monitoring the state of grounding resistance according to claim 1, characterized in that, Establishing the state memory anchor point includes: setting an effective anchor point and an isolation anchor point for the same operating condition; when a newly acquired trusted data segment deviates from the effective anchor point corresponding to the current operating condition, the trusted data segment is written to the isolation anchor point, and the effective anchor point is not updated; when the deviation is determined to be a non-degenerate deviation by prioritizing evidence of contradiction and meets the preset stability condition, or meets the preset migration condition after supplementary sampling under the same operating condition, the effective anchor point is updated with the isolation anchor point.

3. The method for monitoring the state of grounding resistance according to claim 1, characterized in that, For the offset, a collection distortion counter-evidence flag, a common interference counter-evidence flag, and a working condition induced counter-evidence flag are generated respectively, and judged in sequence according to a preset rejection priority; when any counter-evidence flag is valid during the judgment process, a rejection lock flag is set for the offset, and the degradation offset judgment and state advancement are terminated; when all counter-evidence flags are invalid, the offset is judged as a degradation offset, and the same working condition supplementary sampling is triggered.

4. The method for monitoring the state of grounding resistance according to claim 1, characterized in that, The supplementary sampling under the same working condition includes: after the target grounding object re-enters the working condition corresponding to the offset, collecting boundary verification segments and stability verification segments respectively; when the boundary verification segments and stability verification segments maintain the same offset direction as the offset relative to the state memory anchor point corresponding to the current working condition, state advancement is performed; otherwise, the current round of state advancement is terminated.

5. The method for monitoring the state of grounding resistance according to claim 2, characterized in that, An offset direction identifier is attached to the trusted data segment corresponding to the offset, and trusted data segments with the same offset direction relative to the effective anchor point are written to the same isolation anchor point; When the offset direction of the newly acquired trusted data fragment is inconsistent with the offset direction of the data fragment already written in the isolation anchor point, the isolation anchor point is rebuilt.

6. The method for monitoring the state of grounding resistance according to claim 2, characterized in that, After updating the effective anchor point with the isolation anchor point, a freeze period is set for the updated effective anchor point; during the freeze period, even if the newly acquired trusted data fragment is offset relative to the updated effective anchor point, it is still only written to the corresponding isolation anchor point, and the effective anchor point is not updated again.

7. The method for monitoring the state of grounding resistance according to claim 3, characterized in that, The acquisition distortion counter-evidence flag, the co-interference counter-evidence flag, and the operating condition induced counter-evidence flag are constructed into an irreversible priority chain; when the preceding counter-evidence flag is established, the judgment result of the subsequent counter-evidence flag is blocked, and the subsequent counter-evidence flag is prohibited from changing the judgment conclusion corresponding to the preceding counter-evidence flag.

8. The method for monitoring the state of grounding resistance according to claim 3, characterized in that, Associate the rejection lock flag with the current operating condition corresponding to the offset and the offset direction; During the period when the rejection lock flag is valid, for subsequent offsets that enter the current working condition and have the same offset direction, the degradation offset determination and state advancement are directly terminated until a change in working condition or a reversal of offset direction is detected, at which point the rejection lock flag is released.

9. A method for monitoring the state of grounding resistance according to claim 4, characterized in that, Extract a transition constraint segment between the boundary verification segment and the stability verification segment; if the transition constraint segment does not flip in the opposite direction to the offset direction relative to the state memory anchor point corresponding to the current operating condition, execute the state advancement; otherwise, determine the current round of state advancement as an operating condition switching disturbance and terminate it.

10. A method for monitoring the state of grounding resistance according to claim 9, characterized in that, The transition constraint segment is divided into multiple continuous sub-segments, and the offset direction of each continuous sub-segment relative to the state memory anchor point corresponding to the current working condition is determined. When the direction changes alternately between adjacent continuous sub-segments, an oscillation flag is generated, and the current state advancement is determined to be a working condition switching disturbance and terminated. When the offset directions of the multiple continuous sub-segments are all consistent with the offset direction, the state advancement is executed.

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