Grounding resistance online monitoring method and system, storage medium and electronic equipment

Abstract

The invention provides a grounding resistance online monitoring method and system, a storage medium and electronic equipment, and relates to the technical field of grounding resistance monitoring. According to the technical scheme provided by the invention, the geological type of the transformer substation and the reference resistance threshold curve corresponding to the geological type are acquired, the second grounding resistance value is calculated by combining the first grounding resistance value of the branch node in the grounding network, and the comprehensive resistance correction amount is determined based on the soil characteristic parameters; personalized adjustment of the reference resistance threshold curve is realized, and a target resistance threshold curve suitable for a specific transformer substation is obtained. The actually measured third grounding resistance value is compared with the corresponding threshold value of the final resistance threshold value curve, the abnormal state of the grounding network can be accurately identified, the problems of false alarm and missing alarm caused by a fixed threshold value are avoided, and the accuracy of online monitoring of the grounding resistance is improved.

Description

Technical Field

[0001] This application relates to the field of grounding resistance monitoring technology, specifically to an online grounding resistance monitoring method, system, storage medium, and electronic device. Background Technology

[0002] Grounding resistance is a key indicator of the performance of a grounding system, characterizing the ability of a grounding electrode or grounding network to discharge current to the earth. In power systems, reliable grounding is crucial for the safe operation of equipment and the safety of personnel. Grounding resistance is dynamically affected by various factors such as soil resistivity, ambient temperature, and soil moisture; therefore, real-time online monitoring of grounding resistance is necessary to ensure the grounding system is always in good working order.

[0003] Existing grounding resistance monitoring schemes mainly employ a fixed threshold method, comparing the measured grounding resistance value with a pre-set fixed threshold to determine if the grounding system is abnormal. However, in practical applications at railway substations, this monitoring method has significant shortcomings. Different electrical environments along railway lines can interfere with grounding resistance measurements, causing periodic fluctuations in the measured values. Fixed thresholds cannot adapt to these dynamic changes, easily leading to false alarms or missed alarms, thus reducing the accuracy of online grounding resistance monitoring. Summary of the Invention

[0004] This application provides a method, system, storage medium, and electronic device for online monitoring of grounding resistance, which can improve the accuracy of online monitoring of grounding resistance.

[0005] In a first aspect, this application provides a method for online monitoring of grounding resistance, the method comprising: Geological information of multiple substations along the railway line is obtained, the geological type of each substation is determined, and the reference resistance threshold curves corresponding to the geological type under different power consumption environments are obtained. At the start time of the different power consumption environments, the first grounding resistance value of each branch node in the grounding network of the substation is collected, and the second grounding resistance value of the grounding network is calculated based on each of the first grounding resistance values. Obtain soil characteristic parameters of the coverage area of ​​each branch node, and determine the comprehensive resistance correction amount of the soil characteristic parameters to the second grounding resistance value; The reference resistance threshold curve is adjusted based on the second grounding resistance value and the comprehensive resistance correction amount to obtain the target resistance threshold curve; Based on the operating schedules of the different power consumption environments, the curve portion of the target resistance threshold curve corresponding to the time period is denoised to obtain the final resistance threshold curve. The third grounding resistance value of the grounding network is acquired in real time. When the third grounding resistance value exceeds the corresponding threshold of the final resistance threshold curve, an alarm message is generated.

[0006] By adopting the above technical solution, the geological type of the substation and its corresponding reference resistance threshold curve are obtained. Combined with the second grounding resistance value calculated from the first grounding resistance value of the branch nodes in the grounding network, and the comprehensive resistance correction amount determined based on soil characteristic parameters, personalized adjustments to the reference resistance threshold curve are achieved, resulting in a target resistance threshold curve suitable for a specific substation. Furthermore, noise reduction processing of the target resistance threshold curve based on train timetables effectively eliminates the interference of different power consumption environments on grounding resistance measurement. The resulting final resistance threshold curve accurately reflects the normal operating status of the grounding network at different times. During real-time monitoring, comparing the measured third grounding resistance value with the corresponding threshold of the final resistance threshold curve accurately identifies abnormal states of the grounding network, avoiding false alarms and missed alarms caused by fixed thresholds, and improving the accuracy of online grounding resistance monitoring.

[0007] Optionally, the step of acquiring geological information of multiple substations along the railway line, determining the geological type of each substation, and acquiring the reference resistance threshold curve of the geological type under different power consumption environments includes: Geological information of multiple substations along the railway line is obtained, and the geological information is matched with preset standard geological types to determine the geological type of each substation. Obtain the historical resistance threshold curve corresponding to the geological type from the geological type database; The reference curve segment that corresponds to the same historical period in different power consumption environments is extracted from the historical reference resistance threshold curve, and the reference curve segment is determined as the reference resistance threshold curve.

[0008] Optionally, calculating the second grounding resistance value of the grounding network based on each of the first grounding resistance values ​​includes: Obtain the topology information of the grounding network, and construct a spatial structure model of the grounding network based on the topology information; The equivalent coverage space of each initial node is determined according to the spatial structure model, and the initial nodes whose equivalent coverage space is within the preset coverage space threshold are determined as branch nodes. The second grounding resistance value of the grounding network is calculated based on the circuit structure relationship between each of the first grounding resistance values ​​and each of the branch nodes.

[0009] Optionally, calculating the second grounding resistance value of the grounding network based on the circuit structure relationship between each of the first grounding resistance values ​​and each of the branch nodes includes: Based on the circuit structure relationship between each branch node, determine the discharge path from the main branch to the terminal branch in the grounding network; The total resistance of each discharge path is obtained by summing the series resistances of the first resistances of several branch nodes on each discharge path. Select the target discharge path with the smallest total resistance from all the discharge paths, and determine the total resistance of the target discharge path as the second grounding resistance value of the grounding network.

[0010] Optionally, the soil characteristic parameters include soil temperature parameters and soil moisture parameters. The step of obtaining the soil characteristic parameters of the coverage area of ​​each branch node and determining the comprehensive resistance correction amount of the soil characteristic parameters to the second grounding resistance value includes: The soil temperature parameter and the soil moisture parameter are compared with the preset benchmark soil temperature parameter and benchmark soil moisture parameter of the geological type, respectively, to obtain the soil temperature deviation value and the soil moisture deviation value. Query the temperature influence factor corresponding to the soil temperature deviation value and the humidity influence factor corresponding to the soil moisture deviation value from the resistance influence factor library respectively; Based on the temperature influence factor and the humidity influence factor, calculate the initial resistance correction amount of the soil characteristic parameters for each of the first grounding resistance values; Based on the circuit structure relationship, the initial resistance correction values ​​are integrated and calculated to obtain the comprehensive resistance correction value acting on the second grounding resistance value.

[0011] Optionally, the step of denoising the curve portion of the target resistance threshold curve for the corresponding time period based on the operating schedule of the different power consumption environments to obtain the final resistance threshold curve includes: According to the operating timetable, the target resistance threshold curve is divided into train operating periods and train non-operating periods; For the curved portion of the train's running segment, wavelet transform decomposition is used to obtain high-frequency noise and low-frequency baseline, and the periodic fluctuation characteristics caused by train operation are extracted. An adaptive filter is constructed based on the periodic fluctuation characteristics to filter the curved portion of the train's running segment. The filtered curve portion is then spliced ​​with the curve portion during the train's non-operational period to obtain the final resistance threshold curve.

[0012] Optionally, the real-time acquisition of the third grounding resistance value of the grounding network, and the generation of alarm information when the third grounding resistance value exceeds the corresponding threshold of the final resistance threshold curve, including: The third grounding resistance value of the grounding network is obtained in real time, and the curve value at the same moment as the third grounding resistance value is obtained from the final resistance threshold curve according to the system timestamp. The curve values ​​are processed using a cubic exponential smoothing algorithm to obtain the corresponding threshold at the corresponding time. The smoothing coefficient of the cubic exponential smoothing algorithm is determined by minimizing the mean square error. The third grounding resistance value is compared with the corresponding threshold. When the third grounding resistance value exceeds the corresponding threshold, an alarm message is generated.

[0013] Secondly, this application provides an online grounding resistance monitoring system, the system comprising: An initialization module is used to acquire geological information of multiple substations along the railway line, determine the geological type of each substation, and acquire the reference resistance threshold curves corresponding to the geological type in different power consumption environments. The calculation module is used to collect the first grounding resistance value of each branch node in the grounding network of the substation at the start time of the different power consumption environments, and calculate the second grounding resistance value of the grounding network based on each first grounding resistance value; The correction module is used to obtain soil characteristic parameters of the coverage area of ​​each branch node and determine the comprehensive resistance correction amount of the soil characteristic parameters to the second grounding resistance value. The adjustment module is used to adjust the reference resistance threshold curve according to the second grounding resistance value and the comprehensive resistance correction amount to obtain the target resistance threshold curve; The processing module is used to perform noise reduction processing on the curve portion of the target resistance threshold curve corresponding to the time period according to the operating time schedule of the different power consumption environments, so as to obtain the final resistance threshold curve. The monitoring module is used to acquire the third grounding resistance value of the grounding network in real time, and generate an alarm message when the third grounding resistance value exceeds the corresponding threshold of the final resistance threshold curve.

[0014] Thirdly, this application provides a computer storage medium storing a plurality of instructions adapted for loading by a processor and executing any of the methods described above.

[0015] Fourthly, this application provides an electronic device including a processor, a memory, and a transceiver, wherein the memory is used to store instructions, the transceiver is used to communicate with other devices, and the processor is used to execute the instructions stored in the memory to cause the electronic device to perform any of the methods described above.

[0016] In summary, the beneficial effects of the technical solution of this application include: By acquiring the geological type of the substation and its corresponding reference resistance threshold curve, combining the second grounding resistance value calculated from the first grounding resistance value of the branch nodes in the grounding network, and the comprehensive resistance correction amount determined based on soil characteristic parameters, personalized adjustments to the reference resistance threshold curve are achieved, resulting in a target resistance threshold curve suitable for a specific substation. Furthermore, noise reduction processing of the target resistance threshold curve based on train timetables effectively eliminates the interference of traction return current generated by train operation on grounding resistance measurement. The resulting final resistance threshold curve accurately reflects the normal operating status of the grounding network at different times. During real-time monitoring, comparing the measured third grounding resistance value with the corresponding threshold of the final resistance threshold curve accurately identifies abnormal states of the grounding network, avoiding false alarms and missed alarms caused by fixed thresholds, and improving the accuracy of online grounding resistance monitoring. Attached Figure Description

[0017] Figure 1 This is a schematic flowchart of an online grounding resistance monitoring method according to an embodiment of this application; Figure 2 This is a schematic diagram of the structure of an online grounding resistance monitoring system according to an embodiment of this application; Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0018] Explanation of reference numerals in the attached drawings: 300, electronic device; 301, processor; 302, communication bus; 303, user interface; 304, network interface; 305, memory. Detailed Implementation

[0019] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0020] In the description of the embodiments of this application, words such as "illustrative," "for example," or "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "illustrative," "for example," or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design solutions. Rather, the use of words such as "illustrative," "for example," or "for example" is intended to present the relevant concepts in a specific manner.

[0021] In the description of the embodiments of this application, the term "multiple" means two or more. For example, multiple systems means two or more systems, and multiple screen terminals means two or more screen terminals. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. The terms "comprising," "including," "having," and variations thereof all mean "including but not limited to," unless otherwise specifically emphasized.

[0022] Please see Figure 1 This is a flowchart illustrating an online grounding resistance monitoring method provided in this application. This method can be implemented using a computer program, a microcontroller, or run on a grounding resistance online monitoring system based on the von Neumann architecture. The computer program can be integrated into the application or run as a standalone utility application. The specific steps of the online grounding resistance monitoring method are described in detail below.

[0023] S101: Obtain geological information of multiple substations along the railway line, determine the geological type of each substation, and obtain the reference resistance threshold curves corresponding to the geological type under different power consumption environments. Among them, "railway line" refers to the geographical area traversed by the railway line; "substation" refers to the power facilities that convert and distribute electrical energy according to voltage levels; "geological information" represents the geological characteristics that affect grounding resistance, including key parameters such as soil resistivity, soil composition, soil particle size, soil salinity, and groundwater level; "geological type" refers to the category classified according to the geological characteristics that affect grounding resistance, such as high-resistivity sandy soil, low-resistivity clay, and saline-alkali soil; "different power environment" is used to represent the different electrical loads and interference states of the railway power system due to train operation, mainly divided into train operating periods and non-operating periods; "reference resistance threshold curve" refers to the reference curve of grounding resistance changing over time for a specific geological type under standard conditions.

[0024] This step is performed during the system initialization phase to acquire historical data as a monitoring reference standard. Specifically, it first acquires geological information for each substation along the railway line, matches this information with the system's preset standard geological types, and determines which preset geological type each substation belongs to. Then, based on the determined geological type, it retrieves the corresponding resistance threshold curve from the historical database. Finally, from the retrieved historical curves, it extracts historical time periods that match the duration of different current power consumption environments as the benchmark resistance threshold curve. This curve reflects the normal variation range of grounding resistance under this type of geological condition.

[0025] Optionally, this can be achieved through direct database matching: First, key parameters (such as soil resistivity and water content) in the acquired geological information are compared with preset geological type standards in the database; second, a similarity calculation method is used to find the preset geological type with the highest parameter matching degree; finally, the historical monitoring data corresponding to this geological type is directly called to obtain the corresponding baseline resistivity threshold curve. The entire process mainly relies on the existing classification standards and historical data in the database.

[0026] S102: At the start time of different power consumption environments, collect the first grounding resistance value of each branch node in the grounding network of the substation, and calculate the second grounding resistance value of the grounding network based on each first grounding resistance value; Among them, the grounding network refers to the grounding protection system of the substation used to discharge fault current; the branch node refers to the important connection point in the grounding network, including the main node and the terminal node; the first grounding resistance value represents the actual grounding resistance value measured at each branch node; the second grounding resistance value refers to the equivalent resistance value of the entire grounding network calculated by combining the first grounding resistance value of each branch node with the topology of the grounding network.

[0027] This step begins at the start of each different power consumption environment to obtain the initial state of the grounding network. Specifically, at the start of each power consumption environment, the system first identifies all branch nodes in the grounding network and measures the grounding resistance value of each branch node using professional grounding resistance testing equipment to obtain the first grounding resistance value. Then, based on the topology of the grounding network, each discharge path from the main branch to the terminal branch is determined. Next, the sum of the series resistance values ​​on each discharge path is calculated, and the path with the lowest total resistance is selected from all discharge paths. The total resistance value of this path is taken as the second grounding resistance value of the entire grounding network. This second grounding resistance value reflects the actual discharge capacity of the grounding network.

[0028] Optionally, this can be achieved through multi-point synchronous measurement: First, test equipment is simultaneously deployed at each branch node of the grounding network, and measurements are performed using a synchronous triggering method; second, the grounding resistance of each node is measured using the potential drop method, while simultaneously recording the environmental parameters during the measurement; finally, based on the topology of the grounding network, the equivalent resistance of each branch is calculated level by level using the parallel-series equivalent calculation method, ultimately obtaining the second grounding resistance value of the entire network. This method can reduce mutual interference and improve measurement accuracy.

[0029] Alternatively, this can be achieved through zoned measurement: First, the grounding network is divided into multiple measurement zones according to function and structure, with each zone containing several branch nodes; second, the resistance of each branch node in each zone is measured sequentially, using the three-electrode or four-electrode method to obtain accurate grounding resistance values; finally, based on network theory, an equivalent circuit model is established, and combined with the measurement results of each zone, the second grounding resistance value of the entire grounding network is calculated. This method is easy to operate and can reduce workload.

[0030] S103: Obtain the soil characteristic parameters of the coverage area of ​​each branch node, and determine the comprehensive resistance correction amount of the soil characteristic parameters to the second grounding resistance value; Among them, the coverage area of ​​the branch node represents the soil range affected by each branch node; the soil characteristic parameters refer to the key soil indicators that affect the grounding resistance, mainly including soil temperature parameters and soil moisture parameters; the soil temperature parameter represents the actual temperature value of the soil; the soil moisture parameter represents the water content of the soil; the comprehensive resistance correction amount refers to the correction value calculated based on the soil characteristic parameters and used to adjust the second grounding resistance value.

[0031] This step is performed after obtaining the second grounding resistance value and is used to consider the influence of soil environmental factors on the grounding resistance. Specifically, firstly, the soil temperature and humidity parameters within the coverage area of ​​each branch node are obtained. These parameters are compared with the baseline soil temperature and humidity parameters for this geological type to obtain temperature and humidity deviation values. Then, the temperature and humidity influence factors corresponding to these deviation values ​​are searched from a pre-established resistance influence factor library. Next, the initial resistance correction amount for each branch node is calculated based on these influence factors. Finally, according to the circuit structure of the grounding network, the initial resistance correction amounts of all branch nodes are integrated to obtain the comprehensive resistance correction amount acting on the entire grounding network.

[0032] S104: Adjust the reference resistance threshold curve according to the second grounding resistance value and the comprehensive resistance correction amount to obtain the target resistance threshold curve; The target resistance threshold curve refers to the resistance threshold curve that is adjusted for actual environmental factors and is suitable for the current monitoring scenario.

[0033] This step is performed after obtaining the comprehensive resistance correction value, and is used to combine historical data with the actual situation. Specifically, firstly, the second grounding resistance value is calculated with the comprehensive resistance correction value to obtain a corrected resistance value that reflects the current actual situation. Then, based on the ratio between the corrected resistance value and the initial value of the reference resistance threshold curve, an adjustment coefficient is calculated. Next, this adjustment coefficient is applied to all data points of the reference resistance threshold curve, adjusting the entire curve proportionally. Finally, the adjusted curve is used as the target resistance threshold curve, which retains the variation pattern of historical data while reflecting the current on-site situation.

[0034] Optionally, this can be achieved through linear mapping: First, calculate the ratio of the corrected resistance value to the initial value of the reference curve, and use this ratio as the basic adjustment coefficient. Second, considering the potential differences in resistance variation characteristics at different times, divide the duration of different power consumption environments into multiple time periods, and set a weighting coefficient for each time period. Finally, multiply the basic adjustment coefficient by the weighting coefficients of each time period to obtain the piecewise adjustment coefficient, and use this to perform piecewise linear adjustment on the reference curve to generate the target resistance threshold curve. This method can reflect the variation characteristics at different times.

[0035] S105: Based on the operating schedule of different power consumption environments, perform noise reduction processing on the curve portion of the target resistance threshold curve corresponding to the time period to obtain the final resistance threshold curve. Among them, the timetable for different power consumption environments refers to the schedule for recording the actual running and stopping times of the train; the final resistance threshold curve represents the standard curve obtained after noise reduction processing and used for actual monitoring.

[0036] This step, performed after obtaining the target resistance threshold curve, is used to eliminate the interference caused by train operation. Specifically, firstly, based on the train timetable, the target resistance threshold curve is divided into running and non-running segments. Then, wavelet transform decomposition is performed on the curve portion during the running segment to separate high-frequency noise components and low-frequency baseline components, and the periodic fluctuation characteristics caused by train operation are extracted. Next, based on the extracted periodic fluctuation characteristics, an adaptive filter is constructed to filter the curve during the running segment. Finally, the processed curve during the running segment is smoothly connected to the curve during the non-running segment to obtain the final resistance threshold curve.

[0037] S106: Real-time acquisition of the third grounding resistance value of the grounding network. When the third grounding resistance value exceeds the corresponding threshold of the final resistance threshold curve, an alarm message is generated.

[0038] Among them, the third grounding resistance value represents the grounding network resistance value measured in real time, and the alarm information represents the warning data generated by the system when an abnormal situation is detected.

[0039] This step continues after the threshold curve processing is completed, enabling real-time monitoring and early warning of grounding resistance. Specifically, the system first continuously collects the real-time resistance value of the grounding network, i.e., the third grounding resistance value, and records the measurement time. Then, based on the measurement time, the threshold value for the corresponding time is obtained from the final resistance threshold curve. Finally, the measured third grounding resistance value is compared with the corresponding threshold value. When the third grounding resistance value exceeds the threshold range, the system automatically generates an alarm message.

[0040] Optionally, this can be achieved through dynamic threshold comparison: First, collect the third grounding resistance values ​​at multiple times; second, analyze these resistance values ​​and calculate their changing trends; finally, compare the analysis results with the threshold, and generate different levels of alarm information based on the degree of exceedance when the values ​​exceed the preset range. This method can reduce the false alarm rate.

[0041] Based on the above embodiments, as an optional implementation method, the method of determining the geological type of the substation and obtaining the reference resistance threshold curve of the geological type under different power consumption environments in step S101 specifically includes steps S201-S203.

[0042] S201: Obtain geological information of multiple substations along the railway line, match the geological information with preset standard geological types, and determine the geological type of each substation; Among them, the preset standard geological type refers to the typical geological classification with established grounding resistance characteristic relationships, and each type corresponds to a specific grounding resistance variation law. The geological type of the substation represents the standard geological category obtained through matching, which can be used to determine the grounding resistance reference curve of the substation.

[0043] In practice, the standard geological type of a substation is determined by analyzing the geological characteristics affecting grounding resistance. First, a specialized geological survey is conducted around the substation's grounding grid, focusing on measuring soil resistivity distribution and collecting soil samples to determine water content and ionic properties. Second, the measured geological parameters are normalized according to their impact on grounding resistance, constructing a geological feature vector. Then, the similarity between this feature vector and the feature vector of a preset standard geological type is calculated, and the best-matching type is selected as the geological type of the substation. This establishes a correspondence between the substation's grounding device and the grounding resistance variation pattern under specific geological conditions. For example, if a substation has a measured soil resistivity of 100 Ω·m and a water content of 20%, it is determined to be of the "low resistivity clay" type through feature matching, which exhibits specific grounding resistance variation characteristics.

[0044] S202: Obtain the historical resistance threshold curve corresponding to the geological type from the geological type database; In this scheme, the geological type database is a historical dataset of grounding resistance archived by geological type, storing long-term operational data of substation grounding devices under various geological conditions. The historical resistance threshold curve represents the normal grounding resistance variation range of the grounding device under a specific geological type within a complete annual cycle, including resistance fluctuation characteristics caused by factors such as seasonal changes and weather effects.

[0045] This step extracts the standard grounding resistance variation pattern for the target geological type from historical data. First, based on the geological type determined in S201, historical grounding resistance monitoring data for all substations of that type are retrieved from the database. Second, statistical analysis is performed on the historical data for the same geological type, calculating the mean and standard deviation of resistance at each time point. Then, based on the statistical results, upper and lower thresholds for resistance variation are constructed, forming a historical resistance threshold curve for that geological type. This curve reflects the resistance variation pattern of the grounding device under specific geological conditions, providing a basis for subsequently determining the baseline curve. For example, for the "low resistivity clay" type, its historical resistance threshold curve shows a stable seasonal variation pattern: lower and more stable resistance values ​​in summer, and higher and more volatile resistance values ​​in winter.

[0046] S203: Extract a reference curve segment from the historical reference resistance threshold curve that corresponds to the same historical period under different power consumption environments, and determine the reference curve segment as the reference resistance threshold curve.

[0047] The baseline curve segment is the most representative monitoring interval extracted from historical data, and it is required to match the actual operating cycle in terms of time span and operating characteristics. The baseline resistance threshold curve is the final criterion used for real-time monitoring, reflecting the normal grounding resistance variation pattern under specific geological conditions and operating cycles.

[0048] This step combines historical experience with actual operational needs. First, the specific time range and characteristic periods of different current power consumption environments are determined. Second, the historical period most similar to the current operating cycle is found in the historical resistance threshold curve, with a focus on influencing factors such as seasonal characteristics and weather conditions. Then, the curve segment corresponding to this period is extracted and mapped onto the current operating cycle to form a reference resistance threshold curve. The resulting reference curve includes the influence characteristics of geological conditions and matches the actual operating cycle, providing an accurate reference standard for real-time monitoring of grounding devices. For example, if the operating cycle of a substation is 7 days, then 7 days of data under similar weather conditions in the same season are selected from the historical curves as the reference curve.

[0049] Based on the above embodiments, as an optional implementation method, the method of determining the second grounding resistance value of the grounding network according to each first grounding resistance value can be specifically implemented through the following steps S301-S303.

[0050] S301: Obtain the topology information of the grounding network and construct a spatial structure model of the grounding network based on the topology information; The topology information refers to a complete description of the spatial relationships and electrical connections of grounding electrodes and connecting conductors in the grounding network, including the coordinates, burial depth, and specifications of each grounding electrode, as well as the physical parameters such as the direction, length, and cross-section of the connecting conductors. The spatial structure model is a three-dimensional digital model built based on the topology information, which accurately expresses the geometric configuration and electrical connection relationships of the grounding network through mathematical methods.

[0051] This step establishes a digital representation of the grounding network. First, the spatial coordinates (x, y, z) of the grounding electrodes are obtained using measuring equipment such as a total station and GPS, and the spatial arrangement parameters of the connecting conductors are measured. Second, the grounding electrodes are represented as nodes, and the connecting conductors are represented as edges, constructing a network topology based on graph theory. Then, each node is assigned specific physical attribute parameters, including grounding electrode type, size, material, and other information. Finally, a complete three-dimensional digital model is built based on the attributes of the nodes and edges, containing all the geometric and electrical characteristics of the grounding network.

[0052] S302: Determine the equivalent coverage space of each initial node based on the spatial structure model, and determine the initial nodes whose equivalent coverage space is within the preset coverage space threshold as branch nodes; The equivalent coverage space refers to the effective grounding range of a grounding electrode node, determined by the physical parameters of the grounding electrode and soil characteristics. The preset coverage space threshold is the spatial volume standard for determining whether a node is suitable as a measurement point. A branch node refers to a grounding electrode node that meets the measurement conditions.

[0053] This step involves analyzing node characteristics to select suitable measurement points. For each initial node, its equivalent coverage space is calculated based on its location and parameters in the spatial structure model. The calculation considers the physical dimensions of the grounding electrode, its burial depth, and the electrical characteristics of the surrounding soil, expressing the grounding range using an equivalent volume. By comparing the calculated equivalent coverage space with a preset threshold, it is determined which nodes are suitable as independent measurement points. Nodes that meet the coverage space requirements are identified as branch nodes, which will be used for subsequent resistance measurements.

[0054] S303: Calculate the second grounding resistance value of the grounding network based on the circuit structure relationship between each first grounding resistance value and each branch node.

[0055] The first grounding resistance value represents the measured independent grounding resistance of the branch node. The circuit structure relationship refers to the parallel network formed between nodes through connecting conductors. The second grounding resistance value is the equivalent resistance of the entire grounding network.

[0056] This step completes the calculation of the overall resistance of the grounding network. First, independent grounding resistance measurements are performed at all identified branch nodes to obtain the initial grounding resistance value for each node. Then, the electrical connections between these nodes formed by connecting conductors are analyzed to establish a complete equivalent circuit model. The calculation considers both the grounding resistance values ​​of each branch node and the resistance of the connecting conductors. Finally, using the equivalent calculation principle of parallel circuits, the overall equivalent resistance of the entire grounding network, i.e., the second grounding resistance value, is obtained.

[0057] Based on the above embodiments, as an optional implementation method, the method of calculating the second grounding resistance value of the grounding network in step S303 can be specifically implemented through the following steps S3031-S3033.

[0058] S3031: Determine the discharge path from the main branch to the end branch in the grounding network based on the circuit structure relationship between each branch node; The circuit structure relationship refers to the conductor connection relationship between branch nodes in a grounding network, manifested in the connection sequence and direction of the conductors. Main branches are the primary paths for current discharge in a grounding network, typically consisting of conductors with large cross-sectional areas and critical nodes. Terminal branches are branch conductors extending outwards from the grounding network. The discharge path is the complete conductive path of current flowing from the main branches to the terminal branches.

[0059] This step analyzes the actual flow path of the grounding current. Based on the conductor connection structure of the grounding network, a complete network topology is established using graph theory. Starting from the main branch, the network is traced outwards level by level along the conductor connections to identify all possible current discharge paths. During the tracing process, the sequence of branch nodes and conductor connections traversed by each path are recorded. This tracing method ensures that all discharge paths from the main branch to the end are identified, providing complete path information for subsequent resistance calculations.

[0060] S3032: Calculate the sum of the series resistance values ​​of the first resistance values ​​of several branch nodes on each discharge path to obtain the total resistance of each discharge path. The first resistance value is the independent grounding resistance value measured at each branch node. The sum of the series resistance values ​​represents the cumulative value of the resistances of all nodes in the discharge path. The total resistance of the path is the equivalent resistance of a complete discharge path.

[0061] This step calculates the total resistance of each discharge path. For each identified discharge path, the first resistance value of all branch nodes on that path is extracted. These resistance values ​​are then added sequentially according to the current flow direction, along with the resistance values ​​of the connecting conductors. The calculation follows the rules of series circuits, where the total resistance equals the algebraic sum of all resistances along the path. The resulting total resistance reflects the overall conductivity of the discharge path.

[0062] S3033: Select the target discharge path with the smallest total resistance from all discharge paths, and determine the total resistance of the target discharge path as the second grounding resistance value of the grounding network.

[0063] The target discharge path is the current discharge path with the lowest total resistance, representing the path through which grounding current flows most easily. The second grounding resistance value is the equivalent grounding resistance of the entire grounding network, expressed using the resistance value of the optimal discharge path.

[0064] This step determines the equivalent resistance of the grounding network. The total resistance values ​​of all discharge paths are compared, and the path with the lowest value is identified. The reason for choosing the lowest resistance value is that current always tends to flow along the path of least resistance; therefore, the resistance of this path best represents the grounding performance of the entire network. The total resistance value of this path is directly determined as the second grounding resistance value of the grounding network, reflecting the equivalent grounding resistance of the grounding network under actual operating conditions.

[0065] Based on the above embodiments, as an optional implementation method, the method of determining the comprehensive resistance correction amount of the soil characteristic parameters to the second grounding resistance value based on steps S301-S303 can be specifically implemented through the following steps S401-S404.

[0066] S401: Compare the soil temperature parameters and soil moisture parameters with the preset benchmark soil temperature parameters and benchmark soil moisture parameters for the geological type, respectively, to obtain the soil temperature deviation value and soil moisture deviation value. Soil temperature and soil moisture parameters are the currently measured soil environmental parameters. Reference soil temperature and reference soil moisture parameters are the standard parameter values ​​corresponding to the determination of the reference resistance threshold curve for this geological type. Soil temperature deviation and soil moisture deviation values ​​indicate the degree of difference between the current parameters and the reference parameters.

[0067] This step determines the changes in the soil environment through parameter comparison. First, measured values ​​of current soil temperature (T) and humidity (H) are obtained from the soil monitoring system. Simultaneously, the corresponding baseline temperature (T0) and baseline humidity (H0) are retrieved from the geological type database. Then, the temperature deviation ΔT = T - T0 and the humidity deviation ΔH = H - H0 are calculated respectively. These deviation values ​​directly reflect the degree of change in the current soil environment relative to the baseline state.

[0068] S402: Query the temperature influence factor corresponding to the soil temperature deviation value and the humidity influence factor corresponding to the soil moisture deviation value from the resistance influence factor library respectively; The resistance influence factor library is a dataset storing the relationship between changes in different environmental parameters and grounding resistance. The temperature influence factor and humidity influence factor represent the proportion of grounding resistance change caused by a unit change in temperature and a unit change in humidity, respectively.

[0069] This step establishes a quantitative relationship between environmental changes and resistance changes. First, based on the temperature and humidity deviation values ​​obtained in S401, the corresponding influencing factors are retrieved from the resistance influencing factor database. The retrieval of influencing factors employs a piecewise linear interpolation method to ensure accurate influencing factor values ​​are obtained regardless of the parameter deviation range.

[0070] S403: Calculate the initial resistance correction of each first grounding resistance value based on the temperature and humidity influence factors; The initial resistance correction refers to the resistance change of a single grounding electrode node due to environmental influences, reflecting the degree of influence of environmental parameter changes on local grounding resistance.

[0071] This step calculates the resistance correction value caused by environmental changes. For each first grounding resistance value, the resistance correction amounts caused by temperature and humidity changes are calculated separately. The temperature correction amount equals the first grounding resistance value multiplied by the temperature influence factor and then by the temperature deviation value; the humidity correction amount equals the first grounding resistance value multiplied by the humidity influence factor and then by the humidity deviation value. The two correction amounts are then added together to obtain the initial resistance correction amount for that node. This correction amount represents the combined impact of environmental changes on the grounding resistance of a single node.

[0072] S404: Based on the circuit structure, the initial resistance corrections are integrated and calculated to obtain the comprehensive resistance correction applied to the second grounding resistance value.

[0073] The circuit structure represents the electrical connection method of each node in the grounding network. The comprehensive resistance correction is the correction value applied to the equivalent resistance of the entire grounding network.

[0074] This step converts the correction amount of a single node into the correction amount of the entire network. Based on the parallel structure characteristics of the grounding network, a weighted summation method is used to integrate the initial resistance correction amounts of each node. The calculation considers the weight of each node in the parallel network; the weight value is determined by the node's first grounding resistance value, with nodes having larger weights for smaller resistance values. The comprehensive resistance correction amount obtained through weighted calculation reflects the degree of impact of environmental changes on the entire grounding network.

[0075] Based on the above embodiments, as an optional implementation method, the method of obtaining the final resistance threshold curve in step S105 can be specifically achieved through the following steps S501-S504.

[0076] S501: Based on the operating timetable, the target resistance threshold curve is divided into the train operating period and the train non-operating period; A train timetable refers to the detailed schedule of railway train operations, including the specific travel time of each train. Train operating periods are the time intervals during which trains pass by, and the grounding resistance fluctuates due to train activity. Train non-operating periods are the time intervals during which no trains pass by, and the grounding resistance is relatively stable. The target resistance threshold curve is the original grounding resistance variation curve to be processed.

[0077] This step divides the resistance curve into time periods. First, the timetable data is read to extract the running time information for each train, establishing a complete train running time series. Then, all train running segments are marked on the time axis of the target resistance threshold curve, and intervals outside these segments are designated as non-running segments. Time period division uses minute-accurate time stamps to ensure clear boundaries between running and non-running segments.

[0078] S502: For the curved portion of the train running section, wavelet transform decomposition is used to obtain high-frequency noise and low-frequency baseline, and the periodic fluctuation characteristics caused by train operation are extracted. High-frequency noise refers to the rapid resistance fluctuations generated during train operation. The low-frequency baseline represents the basic trend of resistance change. Periodic fluctuation characteristics indicate the regular resistance changes caused by train operation. Wavelet transform is a time-frequency analysis method that can effectively separate different frequency components of a signal.

[0079] This step extracts features through signal processing. For the curve during train operation, a suitable wavelet basis function, such as the Daubechies wavelet, is first selected to decompose the curve into multiple scales. The decomposition process divides the signal into components of different frequency bands. High-frequency components correspond to the rapid fluctuations caused by train operation, while low-frequency components correspond to the basic changing trend of resistance. By analyzing the energy distribution and temporal characteristics of these components, periodic fluctuation patterns are identified.

[0080] S503: An adaptive filter is constructed based on the periodic fluctuation characteristics to filter the curved part of the train running segment; An adaptive filter is a filter that can automatically adjust its parameters based on the characteristics of a signal. Filtering is the process of removing unwanted signal components and retaining the useful signal.

[0081] This step optimizes the resistance curve. Based on the periodic fluctuation characteristics extracted by S502, the structure and parameters of an adaptive filter are designed. The core of the filter is a set of weight coefficients that change with the signal characteristics; these coefficients are continuously updated using the minimum mean square error criterion. The filtering process preserves the main periodic changes reflecting the impact of train operation while suppressing random fluctuations and interference components. The processed curve retains the characteristics of the train operation's influence, but noise is significantly reduced.

[0082] S504: The filtered curve portion is spliced ​​with the curve portion during the non-operational period of the train to obtain the final resistance threshold curve.

[0083] The final resistance threshold curve is a complete standard curve for grounding resistance monitoring, including the optimized operating segment curve and the original non-operating segment curve.

[0084] This step completes the overall construction of the curve. The filtered running segment curve is then stitched together with the unprocessed non-running segment curve in its original time sequence. A smooth transition is applied at the stitching point to ensure the continuity of the curve. The time axis correspondence is maintained during stitching to ensure that the final curve accurately reflects the resistance change characteristics of different time periods. The resulting resistance threshold curve retains the characteristic changes of the train running segment while maintaining the original characteristics of the non-running segment.

[0085] Based on the above embodiments, as an optional implementation method, the method of generating alarm information in step S106 can be specifically implemented through the following steps S601-S603.

[0086] S601: Real-time acquisition of the third grounding resistance value of the grounding network, and acquisition of the curve value at the same moment as the third grounding resistance value from the final resistance threshold curve according to the system timestamp; The third grounding resistance value is the grounding resistance value obtained from real-time measurement of the grounding network. The system timestamp is a marker indicating the time of data acquisition. The final resistance threshold curve is a processed standard threshold curve. The curve value is the resistance value corresponding to a specific moment on the threshold curve.

[0087] This step enables real-time data acquisition and comparison. Resistance data of the grounding network is continuously collected using a grounding resistance measuring device, with each data acquisition accompanied by a precise timestamp. This timestamp is mapped to the time axis of the final resistance threshold curve, and the curve value corresponding to that moment is extracted. The data acquisition frequency is typically set to once per minute to ensure continuous monitoring. The timestamp mapping uses an exact matching method; if a timestamp does not correspond to a sampling point on the curve, the curve value at that moment is calculated through linear interpolation.

[0088] S602: Apply the triple exponential smoothing algorithm to the curve values ​​to obtain the corresponding threshold at the corresponding time. The smoothing coefficient of the triple exponential smoothing algorithm is determined by minimizing the mean square error. Triple exponential smoothing is a time series forecasting method capable of handling trending and seasonal data. The smoothing coefficient is a parameter controlling the degree of smoothing. Mean squared error (MSE) is a measure of the difference between predicted and actual values. The corresponding threshold is a standard judgment value obtained after smoothing.

[0089] This step dynamically optimizes the threshold. The obtained curve value sequence is processed using a cubic exponential smoothing algorithm. The algorithm consists of three equations: a level value equation, a trend equation, and a seasonality equation, each with a corresponding smoothing coefficient. Through iterative calculation, these coefficients are continuously adjusted until the mean square error between the predicted and actual values ​​is minimized. The final smoothing coefficients are used to calculate the corresponding threshold at the current time.

[0090] S603: Compare the third grounding resistance value with the corresponding threshold. When the third grounding resistance value exceeds the corresponding threshold, an alarm message is generated.

[0091] Alarm messages are warnings issued when grounding resistance is abnormal, and include key information such as the time of the abnormality and the abnormal value. The corresponding threshold is the standard value for judging whether the grounding resistance is abnormal.

[0092] This step performs anomaly monitoring and alarm. The real-time measured value of the third grounding resistance is compared with a smoothed corresponding threshold. When the third grounding resistance value exceeds the corresponding threshold, it indicates an abnormality in the grounding network. At this point, an alarm message is generated containing information such as the time, location, and severity of the anomaly.

[0093] The following are system embodiments of this application, which can be used to execute the method embodiments of this application. For details not disclosed in the system embodiments of this application, please refer to the method embodiments of the application.

[0094] Please see Figure 2 This illustration shows a schematic diagram of an online grounding resistance monitoring system provided in an exemplary embodiment of this application. The system can be implemented entirely or partially through software, hardware, or a combination of both. The online grounding resistance monitoring system includes: The initialization module is used to acquire geological information of multiple substations along the railway line, determine the geological type of each substation, and acquire the reference resistance threshold curves corresponding to the geological type under different power consumption environments. The calculation module is used to collect the first grounding resistance value of each branch node in the grounding network of the substation at the start time of different power consumption environments, and calculate the second grounding resistance value of the grounding network based on each first grounding resistance value; The correction module is used to obtain the soil characteristic parameters of the coverage area of ​​each branch node and determine the comprehensive resistance correction amount of the soil characteristic parameters to the second grounding resistance value. The adjustment module is used to adjust the reference resistance threshold curve according to the second grounding resistance value and the comprehensive resistance correction amount to obtain the target resistance threshold curve. The processing module is used to denoise the curve portion of the target resistance threshold curve for the corresponding time period according to the operating schedule of different power consumption environments, so as to obtain the final resistance threshold curve. The monitoring module is used to acquire the third grounding resistance value of the grounding network in real time. When the third grounding resistance value exceeds the corresponding threshold of the final resistance threshold curve, an alarm message is generated.

[0095] Based on the above embodiments, as an optional embodiment, the initialization module is also used to acquire geological information of multiple substations along the railway line, match the geological information with preset standard geological types, and determine the geological type of each substation; acquire the historical resistance threshold curve corresponding to the geological type from the geological type database; and extract the reference curve segment with the same historical period as different power consumption environments from the historical reference resistance threshold curve, and determine the reference curve segment as the reference resistance threshold curve.

[0096] Based on the above embodiments, as an optional embodiment, the calculation module is further used to obtain the topology information of the grounding network, construct a spatial structure model of the grounding network based on the topology information, determine the equivalent coverage space of each initial node based on the spatial structure model, and determine the initial nodes whose equivalent coverage space is within a preset coverage space threshold as branch nodes; calculate the second grounding resistance value of the grounding network based on the circuit structure relationship between each first grounding resistance value and each branch node.

[0097] Based on the above embodiments, as an optional embodiment, the calculation module is further configured to determine the discharge path from the main branch to the terminal branch in the grounding network according to the circuit structure relationship between each branch node; calculate the sum of the series resistance values ​​of the first resistance values ​​of several branch nodes on each discharge path to obtain the total resistance of each discharge path; select the target discharge path with the smallest total resistance from all discharge paths, and determine the total resistance of the target discharge path as the second grounding resistance value of the grounding network.

[0098] Based on the above embodiments, as an optional embodiment, the correction module is further configured to compare the soil temperature parameters and soil moisture parameters with the preset benchmark soil temperature parameters and benchmark soil moisture parameters for the geological type, respectively, to obtain soil temperature deviation values ​​and soil moisture deviation values; query the temperature influence factor corresponding to the soil temperature deviation value and the humidity influence factor corresponding to the soil moisture deviation value from the resistance influence factor library, respectively; calculate the initial resistance correction amount of the soil characteristic parameters for each first grounding resistance value based on the temperature influence factor and the humidity influence factor; and integrate and calculate the initial resistance correction amounts according to the circuit structure relationship to obtain the comprehensive resistance correction amount acting on the second grounding resistance value.

[0099] Based on the above embodiments, as an optional embodiment, the processing module is further configured to divide the target resistance threshold curve into train running periods and train non-running periods according to the operating timetable; for the curve portion during the train running period, wavelet transform decomposition is used to obtain high-frequency noise and low-frequency baseline, and periodic fluctuation features caused by train operation are extracted; an adaptive filter is constructed based on the periodic fluctuation features to filter the curve portion during the train running period; and the filtered curve portion is spliced ​​with the curve portion during the train non-running period to obtain the final resistance threshold curve.

[0100] Based on the above embodiments, as an optional embodiment, the monitoring module is also used to acquire the third grounding resistance value of the grounding network in real time, and to obtain the curve value at the same moment as the third grounding resistance value from the final resistance threshold curve according to the system timestamp; to process the curve value using a cubic exponential smoothing algorithm to obtain the corresponding threshold at the corresponding moment, wherein the smoothing coefficient of the cubic exponential smoothing algorithm is determined by minimizing the mean square error; to compare the third grounding resistance value with the corresponding threshold, and to generate an alarm message when the third grounding resistance value exceeds the corresponding threshold.

[0101] This application also provides a computer-readable storage medium storing instructions that, when executed, perform the steps of any of the methods described above.

[0102] In one exemplary embodiment, the aforementioned computer-readable storage medium may include, but is not limited to, various media capable of storing computer programs, such as a USB flash drive, read-only memory (ROM), random access memory (RAM), portable hard disk, magnetic disk, or optical disk.

[0103] This application also discloses an electronic device. For example... Figure 3 As shown, Figure 3 This is a schematic diagram of the structure of an electronic device disclosed in an embodiment of this application. The electronic device 300 may include: at least one processor 301, at least one communication bus 302, a user interface 303, at least one network interface 304, and a memory 305.

[0104] The communication bus 302 is used to enable communication between these components.

[0105] The user interface 303 may include a display screen, and optionally, the user interface 303 may also include a standard wired interface or a wireless interface.

[0106] The network interface 304 may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface).

[0107] The processor 301 may include one or more processing cores. The processor 301 connects to various parts of the electronic device (such as a server) using various interfaces and lines, and performs various server functions and processes data by running or executing instructions, programs, code sets, or instruction sets stored in memory 305, and by calling data stored in memory 305. Optionally, the processor 301 may be implemented using at least one hardware form of Digital Signal Processing (DSP), Field-Programmable Gate Array (FPGA), or Programmable Logic Array (PLA). The processor 301 may integrate one or a combination of several of the following: Central Processing Unit (CPU), Graphics Processing Unit (GPU), and modem. The CPU primarily handles the operating system, user interface, and applications; the GPU is responsible for rendering and drawing the content required for display; and the modem handles wireless communication. It is understood that the modem may also not be integrated into the processor 301 and may be implemented as a separate chip.

[0108] The memory 305 may include random access memory (RAM) or read-only memory. Optionally, the memory 305 may include a non-transitory computer-readable storage medium. The memory 305 may be used to store instructions, programs, code, code sets, or instruction sets. The memory 305 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for at least one function (such as touch function, sound playback function, image playback function, etc.), instructions for implementing the above-described method embodiments, etc.; the data storage area may store data involved in the above-described method embodiments, etc. Optionally, the memory 305 may also be at least one storage device located remotely from the aforementioned processor 301. (Refer to...) Figure 3 The memory 305, which serves as a computer storage medium, may include an operating system, a network communication module, a user interface module, and an application program for an online monitoring method of a power transformer.

[0109] exist Figure 3In the illustrated electronic device 300, the user interface 303 is mainly used to provide an input interface for the user and to acquire user input data; while the processor 301 can be used to call an application program for an online monitoring method of a power transformer stored in the memory 305. When executed by one or more processors 301, the electronic device 300 performs one or more of the methods described in the above embodiments. It should be noted that, for the foregoing method embodiments, for the sake of simplicity, they are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, because according to this application, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also understand that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0110] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0111] In the various embodiments provided in this application, it should be understood that the disclosed apparatus or system can be implemented in other ways. For example, the apparatus or system embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some service interface; the indirect coupling or communication connection between apparatuses or units may be electrical or other forms.

[0112] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0113] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0114] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage device (CMD). Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned memory includes various media capable of storing program code, such as USB flash drives, portable hard drives, magnetic disks, or optical disks.

[0115] The above description is merely an exemplary embodiment of this disclosure and should not be construed as limiting the scope of this disclosure. Any equivalent changes and modifications made in accordance with the teachings of this disclosure shall still fall within the scope of this disclosure. Other embodiments of this disclosure will be readily apparent to those skilled in the art upon consideration of the disclosure herein.

[0116] This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art that are not described in this disclosure.

Claims

1. A method for online monitoring of grounding resistance, characterized in that, The method includes: Geological information of multiple substations along the railway line is obtained, the geological type of each substation is determined, and the reference resistance threshold curves corresponding to the geological type under different power consumption environments are obtained. At the start time of the different power consumption environments, the first grounding resistance value of each branch node in the grounding network of the substation is collected, and the second grounding resistance value of the grounding network is calculated based on each of the first grounding resistance values. Obtain soil characteristic parameters of the coverage area of ​​each branch node, and determine the comprehensive resistance correction amount of the soil characteristic parameters to the second grounding resistance value; The reference resistance threshold curve is adjusted based on the second grounding resistance value and the comprehensive resistance correction amount to obtain the target resistance threshold curve; Based on the operating schedules of the different power consumption environments, the curve portion of the target resistance threshold curve corresponding to the time period is denoised to obtain the final resistance threshold curve. The third grounding resistance value of the grounding network is acquired in real time. When the third grounding resistance value exceeds the corresponding threshold of the final resistance threshold curve, an alarm message is generated.

2. The method according to claim 1, characterized in that, The process of acquiring geological information of multiple substations along the railway line, determining the geological type of each substation, and acquiring the reference resistance threshold curves of the geological type under different power consumption environments includes: Geological information of multiple substations along the railway line is obtained, and the geological information is matched with preset standard geological types to determine the geological type of each substation. Obtain the historical resistance threshold curve corresponding to the geological type from the geological type database; The reference curve segment that corresponds to the same historical period in different power consumption environments is extracted from the historical reference resistance threshold curve, and the reference curve segment is determined as the reference resistance threshold curve.

3. The method according to claim 1, characterized in that, The step of calculating the second grounding resistance value of the grounding network based on each of the first grounding resistance values ​​includes: Obtain the topology information of the grounding network, and construct a spatial structure model of the grounding network based on the topology information; The equivalent coverage space of each initial node is determined according to the spatial structure model, and the initial nodes whose equivalent coverage space is within the preset coverage space threshold are determined as branch nodes. The second grounding resistance value of the grounding network is calculated based on the circuit structure relationship between each of the first grounding resistance values ​​and each of the branch nodes.

4. The method according to claim 3, characterized in that, The step of calculating the second grounding resistance value of the grounding network based on the circuit structure relationship between each of the first grounding resistance values ​​and each of the branch nodes includes: Based on the circuit structure relationship between each branch node, determine the discharge path from the main branch to the terminal branch in the grounding network; The total resistance of each discharge path is obtained by summing the series resistances of the first resistances of several branch nodes on each discharge path. Select the target discharge path with the smallest total resistance from all the discharge paths, and determine the total resistance of the target discharge path as the second grounding resistance value of the grounding network.

5. The method according to claim 3, characterized in that, The soil characteristic parameters include soil temperature parameters and soil moisture parameters. The step of obtaining the soil characteristic parameters of the coverage area of ​​each branch node and determining the comprehensive resistance correction amount of the soil characteristic parameters to the second grounding resistance value includes: The soil temperature parameter and the soil moisture parameter are compared with the preset benchmark soil temperature parameter and benchmark soil moisture parameter of the geological type, respectively, to obtain the soil temperature deviation value and the soil moisture deviation value. Query the temperature influence factor corresponding to the soil temperature deviation value and the humidity influence factor corresponding to the soil moisture deviation value from the resistance influence factor library respectively; Based on the temperature influence factor and the humidity influence factor, calculate the initial resistance correction amount of the soil characteristic parameters for each of the first grounding resistance values; Based on the circuit structure relationship, the initial resistance correction values ​​are integrated and calculated to obtain the comprehensive resistance correction value acting on the second grounding resistance value.

6. The method according to claim 1, characterized in that, The step of denoising the corresponding time period portion of the target resistance threshold curve based on the operating schedule of the different power consumption environments to obtain the final resistance threshold curve includes: According to the operating timetable, the target resistance threshold curve is divided into train operating periods and train non-operating periods; For the curved portion of the train's running segment, wavelet transform decomposition is used to obtain high-frequency noise and low-frequency baseline, and the periodic fluctuation characteristics caused by train operation are extracted. An adaptive filter is constructed based on the periodic fluctuation characteristics to filter the curved portion of the train's running segment. The filtered curve portion is then spliced ​​with the curve portion during the train's non-operational period to obtain the final resistance threshold curve.

7. The method according to claim 1, characterized in that, The third grounding resistance value of the grounding network is acquired in real time. When the third grounding resistance value exceeds the corresponding threshold of the final resistance threshold curve, an alarm message is generated, including: The third grounding resistance value of the grounding network is obtained in real time, and the curve value at the same moment as the third grounding resistance value is obtained from the final resistance threshold curve according to the system timestamp. The curve values ​​are processed using a cubic exponential smoothing algorithm to obtain the corresponding threshold at the corresponding time. The smoothing coefficient of the cubic exponential smoothing algorithm is determined by minimizing the mean square error. The third grounding resistance value is compared with the corresponding threshold. When the third grounding resistance value exceeds the corresponding threshold, an alarm message is generated.

8. A grounding resistance online monitoring system, characterized in that, The system includes: An initialization module is used to acquire geological information of multiple substations along the railway line, determine the geological type of each substation, and acquire the reference resistance threshold curves corresponding to the geological type under different power consumption environments. The calculation module is used to collect the first grounding resistance value of each branch node in the grounding network of the substation at the start time of the different power consumption environments, and calculate the second grounding resistance value of the grounding network based on each first grounding resistance value; The correction module is used to obtain soil characteristic parameters of the coverage area of ​​each branch node and determine the comprehensive resistance correction amount of the soil characteristic parameters to the second grounding resistance value. The adjustment module is used to adjust the reference resistance threshold curve according to the second grounding resistance value and the comprehensive resistance correction amount to obtain the target resistance threshold curve; The processing module is used to perform noise reduction processing on the curve portion of the target resistance threshold curve corresponding to the time period according to the operating time schedule of the different power consumption environments, so as to obtain the final resistance threshold curve. The monitoring module is used to acquire the third grounding resistance value of the grounding network in real time, and generate an alarm message when the third grounding resistance value exceeds the corresponding threshold of the final resistance threshold curve.

9. A computer storage medium, characterized in that, The computer storage medium stores a plurality of instructions, which are adapted to be loaded by a processor and executed as described in any one of claims 1 to 7.

10. An electronic device, characterized in that, The device includes a processor, a memory, and a transceiver, wherein the memory is used to store instructions, the transceiver is used to communicate with other devices, and the processor is used to execute the instructions stored in the memory to cause the electronic device to perform the method as described in any one of claims 1 to 7.

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