Power distribution network voltage disturbance source positioning method and device, medium and program product

Abstract

The invention discloses a power distribution network voltage disturbance source positioning method and device, a medium and a program product, and belongs to the field of positioning, and the method comprises the steps: obtaining the network topology and line impedance parameters of a power distribution network and real-time voltage monitoring data, constructing an equivalent impedance matrix and an electrical distance matrix, recognizing a voltage disturbance event, and extracting a response time difference. And combining the electrical distance matrix and the disturbance propagation speed to construct an error function so as to determine a preliminary disturbance source node, and verifying whether the preliminary disturbance source node is an actual disturbance source through a parameter identification method. If verification is passed, the deviation between the theoretical disturbance arrival time and the actual disturbance arrival time is calculated, the positioning error is evaluated, and finally a high-precision disturbance source positioning result is obtained, and the problem that the voltage disturbance source of the power distribution network cannot be accurately and efficiently positioned in the prior art is effectively solved.

Description

Technical Field

[0001] This invention relates to the field of positioning, and in particular to a method, device, medium, and program product for locating voltage disturbance sources in power distribution networks. Background Technology

[0002] In the operation of modern power distribution networks, with the rapid popularization and integration of distributed energy sources such as photovoltaics and wind power, and the continuous growth of diversified loads such as electric heavy trucks and variable frequency air conditioners, the frequency and complexity of voltage disturbance events have significantly increased. The output of distributed energy sources is highly volatile due to the influence of the natural environment, which can easily lead to phased increases or decreases in the voltage of the distribution area. At the same time, sudden changes in load, line switch operations, and fault switching operations can also cause transient or continuous voltage disturbances. These problems not only affect the normal operation of end-user electrical equipment, but also pose potential risks to the safe and stable operation of the power distribution network. In severe cases, they may trigger cascading failures, threatening the continuity and reliability of power supply.

[0003] Existing methods for locating voltage disturbance sources in distribution networks have numerous limitations, making it difficult to meet the precise location requirements under complex operating conditions. Some methods rely on synchronous phasor measurement equipment, which requires extremely high clock synchronization accuracy and incurs high deployment and maintenance costs, hindering large-scale application. Other methods rely solely on voltage amplitude or phase difference analysis, neglecting the non-uniformity of distribution network parameters and becoming susceptible to variations in line impedance and topological complexity, leading to significant location errors. Still other methods are based on power flow inversion techniques, heavily reliant on the accuracy of network parameters and load models, and often fail in practical applications due to parameter uncertainties, data noise, and incomplete data. Furthermore, traditional location methods generally lack effective secondary verification mechanisms, making it difficult to quantitatively verify preliminary location results, leading to false alarms or missed detections, and failing to provide a reliable basis for subsequent power quality management. These shortcomings prevent existing technologies from accurately and efficiently locating voltage disturbance sources in distribution networks. Summary of the Invention

[0004] This invention provides a method, device, medium, and program product for locating voltage disturbance sources in power distribution networks, in order to solve the problem that existing technologies cannot accurately and efficiently locate voltage disturbance sources in power distribution networks.

[0005] Firstly, this application provides a method for locating voltage disturbance sources in a distribution network, including: Obtain network topology parameters, line impedance parameters, and real-time voltage monitoring data of each node in the power distribution network; Based on the network topology parameters and line impedance parameters, an equivalent impedance matrix between each node of the distribution network is constructed, and the electrical distance matrix between each node is calculated based on the equivalent impedance matrix. Based on the real-time voltage monitoring data, voltage disturbance events in the distribution network are identified, and the response time difference of each first node triggering the voltage disturbance is extracted; wherein, each first node is a node that meets the preset voltage disturbance judgment conditions; Based on the response time difference and the preset disturbance propagation speed, combined with the electrical distance matrix, a disturbance propagation path error function is constructed, and the initial disturbance source node is determined by minimizing the error function; Based on the electrical distance matrix and the preset disturbance propagation speed, the preliminary disturbance source node is verified by a preset parameter identification method to determine whether the preliminary disturbance source node is the actual disturbance source. If the initial disturbance source node is the actual disturbance source, calculate the deviation between the theoretical disturbance arrival time and the actual disturbance arrival time of each first node, evaluate the positioning error of the initial disturbance source node based on the deviation, and obtain the positioning result of the actual disturbance source.

[0006] This application first constructs an equivalent impedance matrix and an electrical distance matrix by acquiring network topology parameters and line impedance parameters of the distribution network and combining them with real-time voltage monitoring data of each node. This provides a precise network model foundation for disturbance source location. This basic model accurately reflects the electrical relationships between nodes, solving the location error problem caused by inaccurate network parameters in existing technologies. Based on this, voltage disturbance events are identified using real-time voltage monitoring data, and the response time difference is extracted. A disturbance propagation path error function is constructed by combining the electrical distance matrix and a preset disturbance propagation speed. The initial disturbance source node is determined by minimizing the error function. This process utilizes the temporal characteristics of disturbance propagation, avoiding the inaccurate location problem caused by relying solely on voltage amplitude or phase difference in traditional methods. Furthermore, the initial disturbance source node is verified using a parameter identification method to ensure its authenticity. This verification step compensates for the lack of a secondary verification mechanism in existing technologies, effectively reducing the risk of false alarms and missed detections. Finally, the location error is evaluated by calculating the deviation between the theoretical and actual disturbance arrival times, resulting in an accurate disturbance source location. This process not only improves the positioning accuracy, but also enhances the robustness and adaptability of the method. This application effectively solves the problem that existing technologies cannot accurately and efficiently locate voltage disturbance sources in distribution networks.

[0007] Furthermore, based on the network topology parameters and line impedance parameters, an equivalent impedance matrix is ​​constructed between each node of the distribution network, and the electrical distance matrix between each node is calculated based on the equivalent impedance matrix, specifically as follows: Construct a node model that includes transformers, loads, and photovoltaic access points in the distribution network; Based on the network topology parameters and line impedance parameters, and combined with the node model, calculate the self-impedance of each node and the mutual impedance between any two nodes. Arrange all self-impedances and mutual impedances according to the node number to obtain the equivalent impedance matrix between nodes of the distribution network; Based on the resistance and reactance values ​​corresponding to each element in the equivalent impedance matrix, the electrical distance between any two nodes is calculated. Arrange the electrical distances between all nodes according to their node numbers to obtain the electrical distance matrix between nodes in the distribution network.

[0008] This application constructs a model including key nodes in the distribution network such as transformers, loads, and photovoltaic access points. Based on network topology parameters and line impedance parameters, it calculates the self-impedance and mutual impedance of each node, ultimately forming an equivalent impedance matrix. This process accurately reflects the electrical connections between nodes in the distribution network, providing an accurate network foundation model for subsequent disturbance source location. Furthermore, the electrical distances between nodes are calculated using the resistance and reactance values ​​in the equivalent impedance matrix, forming an electrical distance matrix. The establishment of the electrical distance matrix makes the analysis of disturbance propagation paths more consistent with actual physical processes, effectively overcoming the location error problem caused by neglecting the non-uniformity of network parameters in traditional methods. Through this electrical distance calculation based on an accurate network model, this application can more accurately identify the location of disturbance sources, improving the accuracy and reliability of location, and providing strong technical support for power quality management and operation and maintenance decisions in the distribution network.

[0009] Furthermore, the step of identifying voltage disturbance events in the distribution network based on the real-time voltage monitoring data and extracting the response time difference of each first node triggering the voltage disturbance specifically involves: Real-time voltage monitoring data of each node is collected through a preset voltage sampling device. The real-time voltage monitoring data of each node is compared with the preset voltage disturbance judgment conditions. If the real-time voltage monitoring data of any node meets the voltage disturbance judgment conditions, it is determined that a voltage disturbance event has occurred in the distribution network, and the voltage disturbance trigger time of each first node that meets the voltage disturbance judgment conditions is obtained. Using the initially acquired voltage disturbance trigger time as the reference time, calculate the differences between the voltage disturbance trigger time of each remaining node in each first node and the reference time, and use each difference as the response time difference of each first node triggering the voltage disturbance.

[0010] This application uses a pre-set voltage sampling device to collect voltage data from each node of the distribution network in real time and compares it with pre-set voltage disturbance judgment conditions. When the voltage data of any node meets the disturbance judgment conditions, a voltage disturbance event is determined to have occurred, and the disturbance trigger time of that node is recorded as a reference time. The difference between the disturbance trigger times of other nodes and the reference time is further calculated to obtain the response time difference. This process can accurately capture the occurrence time and propagation sequence of voltage disturbances, providing crucial time information for subsequent disturbance source localization. Through this method, the present invention effectively solves the problem of inaccurate localization caused by the lack of precise time information in traditional methods, while improving the detection sensitivity and response speed of disturbance events. This lays the foundation for achieving high-precision disturbance source localization and significantly improves the efficiency and reliability of power quality monitoring and management in the distribution network.

[0011] Furthermore, based on the response time difference and the preset disturbance propagation speed, combined with the electrical distance matrix, a disturbance propagation path error function is constructed, and the initial disturbance source node is determined by minimizing the error function, specifically as follows: The response time difference of each first node is compared with the preset maximum response time threshold, and nodes whose response time difference is less than the maximum response time threshold are selected to obtain the first candidate node set. Extract the initial voltage jump amplitude at the voltage disturbance trigger time of each first node, compare the initial voltage jump amplitude with a preset initial voltage jump threshold, and filter out nodes whose initial voltage jump amplitude is greater than the initial voltage jump threshold to obtain a second candidate node set; Obtain the intersection of the first candidate node set and the second candidate node set to obtain the candidate disturbance source node set; Based on each candidate node in the candidate disturbance source node set, extract each electrical distance from each candidate node to each first node from the electrical distance matrix; Based on the electrical distances mentioned above, and in conjunction with the preset disturbance propagation speed, the theoretical response time of each candidate node is calculated. The theoretical response time is compared with the difference between the actual response time of each candidate node to construct a disturbance propagation path error function; wherein, the error function is used to characterize the degree of deviation between the theoretical response time and the actual response time difference; Based on the disturbance propagation path error function, calculate the error function value of each candidate node in the candidate disturbance source node set, and select the candidate node with the smallest error function value as the initial disturbance source node.

[0012] This application forms a candidate disturbance source node set by screening nodes with response time differences less than a preset threshold and nodes with initial voltage jump amplitudes greater than a preset threshold. This screening process effectively narrows down the possible range of disturbance sources, eliminating nodes with excessively long response times or insignificant voltage changes, thereby improving the accuracy of location. Furthermore, by combining the electrical distance matrix and a preset disturbance propagation velocity, the theoretical response time of each candidate node is calculated and compared with the actual response time difference to construct a disturbance propagation path error function. By minimizing the error function to determine the initial disturbance source nodes, this process fully utilizes the physical laws of disturbance propagation and actual monitoring data, ensuring the scientific rigor and reliability of disturbance source location. Compared with traditional methods, this invention, by introducing an error function to optimize the location process, effectively solves the location error problem caused by network parameter uncertainties and data noise in existing technologies, significantly improving the accuracy and robustness of disturbance source location, and providing more precise technical support for power quality management in distribution networks.

[0013] Furthermore, the step of verifying the preliminary disturbance source node based on the electrical distance matrix and a preset disturbance propagation speed using a preset parameter identification method to determine whether the preliminary disturbance source node is an actual disturbance source specifically involves: Based on the initial disturbance source node, the electrical distance from the initial disturbance source node to each first node is extracted from the electrical distance matrix; Based on the preset disturbance propagation speed, the initial theoretical disturbance arrival time of the disturbance signal from the initial disturbance source node to each first node is calculated. The initial actual disturbance arrival time of each first node is extracted from the real-time voltage monitoring data; wherein, the initial actual disturbance arrival time is the time when each first node first meets the voltage disturbance judgment condition; The rank correlation coefficient is calculated by comparing the difference between the initial actual arrival times of any two nodes with the difference between the initial theoretical arrival times of the disturbance. If the rank correlation coefficient meets the preset judgment threshold, the preliminary disturbance source node is determined to be the actual disturbance source.

[0014] This application extracts the electrical distance from the initial disturbance source node to each monitoring node and calculates the initial theoretical disturbance arrival time by combining it with a preset disturbance propagation speed. Simultaneously, it obtains the actual disturbance arrival time of each node from real-time monitoring data. By comparing the difference between the theoretical and actual disturbance arrival times, a rank correlation coefficient is calculated to verify the authenticity of the initial disturbance source node. This verification process not only considers the physical laws of disturbance propagation but also introduces statistical methods (rank correlation coefficient) to quantify the consistency between theoretical and actual data. Compared with traditional methods, this approach effectively avoids misjudgments caused by uncertainties in a single parameter or model, significantly improving the reliability and accuracy of disturbance source location. Through this dual verification mechanism, this application can accurately determine the disturbance source even under complex operating conditions, providing a more reliable decision-making basis for power quality management in distribution networks.

[0015] Furthermore, if the initial disturbance source node is the actual disturbance source, the deviation between the theoretical disturbance arrival time and the actual disturbance arrival time of each first node is calculated. Based on the deviation, the positioning error of the initial disturbance source node is evaluated to obtain the positioning result of the actual disturbance source, specifically as follows: If the initial disturbance source node is determined to be the actual disturbance source, the theoretical disturbance arrival time of each first node is recalculated based on the initial disturbance source node, combined with the electrical distance from the initial disturbance source node to each first node in the electrical distance matrix and the preset disturbance propagation speed. The actual arrival time of each first node is extracted from the real-time voltage monitoring data. The difference between the theoretical arrival time of each first node and the actual arrival time of the disturbance is calculated to obtain the disturbance time deviation of each first node. The disturbance time deviations of all first nodes are statistically analyzed, and the arithmetic mean of all disturbance time deviations is calculated as the average positioning error. The deviation with the largest absolute value is selected from all the deviations at all disturbance times as the maximum positioning error; The average positioning error and the maximum positioning error are used as the positioning error evaluation results. Combined with the location information of the actual disturbance source node, the positioning result of the actual disturbance source is obtained.

[0016] After determining that the preliminary disturbance source node is the actual disturbance source, this application recalculates the theoretical disturbance arrival time of each monitoring node and compares it with the actual disturbance arrival time to calculate the disturbance time deviation of each node. Furthermore, the arithmetic mean of all deviations is calculated as the average positioning error, and the deviation with the largest absolute value is selected as the maximum positioning error. This error assessment method not only quantifies the positioning accuracy but also comprehensively reflects the reliability and stability of the positioning results through the dual indicators of average error and maximum error. Compared with traditional methods, this invention provides a more scientific quantitative basis for disturbance source positioning through precise error assessment, effectively avoiding misjudgments caused by excessive positioning errors, and significantly improving the accuracy and reliability of power distribution network voltage disturbance source positioning.

[0017] Secondly, this application provides a distribution network voltage disturbance source location device. The distribution network voltage disturbance source location device includes: The acquisition module is used to acquire network topology parameters, line impedance parameters, and real-time voltage monitoring data of each node in the distribution network. The construction module is used to construct the equivalent impedance matrix between each node of the distribution network based on the network topology parameters and line impedance parameters, and to calculate the electrical distance matrix between each node based on the equivalent impedance matrix. The extraction module is used to identify voltage disturbance events in the distribution network based on the real-time voltage monitoring data and extract the response time difference of each first node that triggers the voltage disturbance; wherein, each first node is a node that meets the preset voltage disturbance judgment conditions; The determination module is used to construct a disturbance propagation path error function based on the response time difference and a preset disturbance propagation speed, combined with the electrical distance matrix, and to determine the initial disturbance source node by minimizing the error function; The judgment module is used to verify the preliminary disturbance source node based on the electrical distance matrix and the preset disturbance propagation speed, and to determine whether the preliminary disturbance source node is the actual disturbance source. The positioning module is used to calculate the deviation between the theoretical arrival time of the disturbance and the actual arrival time of each first node if the preliminary disturbance source node is the actual disturbance source, evaluate the positioning error of the preliminary disturbance source node based on the deviation, and obtain the positioning result of the actual disturbance source.

[0018] This application's distribution network voltage disturbance source location device collects network topology parameters, line impedance parameters, and real-time voltage monitoring data through an acquisition module, providing comprehensive foundational data for subsequent analysis. The construction module uses these parameters to construct an equivalent impedance matrix and an electrical distance matrix, accurately characterizing the electrical characteristics of the distribution network and laying the foundation for disturbance propagation analysis. The extraction module identifies voltage disturbance events and extracts response time differences from monitoring data, providing crucial time information for disturbance source location. The determination module combines the electrical distance matrix and disturbance propagation velocity to construct an error function, determining the initial disturbance source node by minimizing the error function, thus improving the initial location accuracy. The judgment module further verifies the authenticity of the initial disturbance source node, ensuring the reliability of the location results through parameter identification methods. Finally, the location module evaluates the location error and outputs a high-precision disturbance source location result. This device, through the collaborative work of its modules, solves the location error problems caused by incomplete data, inaccurate models, and lack of verification mechanisms in traditional methods, achieving high-precision and high-reliability disturbance source location under complex operating conditions.

[0019] Thirdly, this application provides a computer-readable storage medium comprising a stored computer program, wherein, when the computer program is executed, it controls the device containing the computer-readable storage medium to perform the power distribution network voltage disturbance source localization method as described above. Its beneficial effects are the same as those of the power distribution network voltage disturbance source localization method provided in the first aspect of this application.

[0020] Fourthly, this application provides a computer program product, comprising: a computer program that, when executed by a processor, implements the distribution network voltage disturbance source location method described in the first aspect. Attached Figure Description

[0021] Figure 1 : A schematic flowchart of an embodiment of the distribution network voltage disturbance source location method provided in this application; Figure 2 : A schematic diagram of an embodiment of the distribution network voltage disturbance source locating device provided in this application. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1 Please refer to Figure 1In order to solve the problem that existing technologies cannot accurately and efficiently locate voltage disturbance sources in distribution networks, this invention provides a method for locating voltage disturbance sources in distribution networks, including steps S01-S06.

[0024] S01: Obtain network topology parameters, line impedance parameters, and real-time voltage monitoring data of each node in the distribution network.

[0025] In a preferred embodiment of this invention, the acquisition of network topology parameters, line impedance parameters, and real-time voltage monitoring data of each node of the distribution network specifically includes: When locating voltage disturbance sources in a distribution network, the first step is to comprehensively collect and integrate basic data, including network topology parameters, line impedance parameters, and real-time voltage monitoring data for each node. Network topology parameters are obtained through distribution network dispatch automation systems or geographic information systems, covering the distribution location of all nodes, the connections between nodes, line branching, and the installation locations and connection methods of key components such as transformers and switching equipment, clearly presenting the overall structure and component layout of the distribution network. Line impedance parameters are obtained through actual line parameter measurements or by consulting equipment manufacturer technical data, including the resistance and reactance values ​​of each section of the distribution network. These parameters directly reflect the line's resistance characteristics to power transmission and energy loss patterns. Meanwhile, voltage sampling devices are deployed at each monitoring node of the distribution network. These devices continuously collect voltage data from each node according to a preset sampling frequency to form real-time voltage monitoring data. The preset sampling frequency is determined based on the minimum duration of the disturbance signal. The collected data not only includes voltage amplitude information but also records the timestamp of the corresponding voltage data collection, ensuring that the time characteristics of voltage changes at each node can be accurately traced during subsequent analysis. This provides complete and accurate basic data support for subsequent voltage disturbance event identification, response time difference extraction, and disturbance source location calculation.

[0026] S02: Based on the network topology parameters and line impedance parameters, construct the equivalent impedance matrix between each node of the distribution network, and calculate the electrical distance matrix between each node based on the equivalent impedance matrix.

[0027] In a preferred embodiment of this invention, the step of constructing an equivalent impedance matrix between nodes of the distribution network based on the network topology parameters and line impedance parameters, and calculating the electrical distance matrix between nodes based on the equivalent impedance matrix, specifically involves: After obtaining the network topology parameters and line impedance parameters of the distribution network, the equivalent impedance matrix between each node of the distribution network is first constructed based on these basic parameters. Specifically, the number, number, and connection relationship between all nodes in the distribution network are first determined according to the network topology parameters. At the same time, the corresponding node models are constructed in combination with the characteristics of components such as transformers, loads, and photovoltaic access points, clearly defining the electrical connection mode and equivalent parameters of each component in the distribution network. Subsequently, based on the line impedance parameters, the self-impedance of each node and the mutual impedance between any two different nodes are solved by the electrical equivalent calculation method. The self-impedance represents the equivalent electrical impedance characteristic of a single node itself, and the mutual impedance represents the equivalent electrical coupling characteristic formed between two nodes through lines and components. The self-impedance of all nodes is arranged in order of node number on the diagonal of the matrix, and the mutual impedance between any two nodes is arranged in order of corresponding node number on the off-diagonal of the matrix, thus forming a complete equivalent impedance matrix between each node of the distribution network. More specifically, assuming there are 𝑁 nodes in the distribution network (including transformers, loads, photovoltaic access points, etc.), calculate the equivalent impedance matrix between the nodes based on the network topology and parameters. Its expression is as follows: In the formula, diagonal elements For nodes i Self-impedance; off-diagonal elements This is the equivalent impedance (i.e., mutual impedance) between node i and node j. For resistance value, This represents the reactance value.

[0028] Calculate the electrical distance matrix based on the equivalent impedance matrix. The calculation formula is as follows: In the formula, element Represents a node i arrive j The electrical distance is calculated using the following formula: .

[0029] The electrical distance between the two nodes corresponding to the element is obtained. This electrical distance can accurately reflect the propagation characteristics and equivalent transmission distance of the disturbance signal between the two nodes. According to the node number arrangement rules of the equivalent impedance matrix, the calculated electrical distances between all nodes are filled into the corresponding positions in sequence to finally form the electrical distance matrix between each node of the distribution network, which provides core electrical characteristic parameters to support the subsequent disturbance propagation path analysis and disturbance source location calculation.

[0030] S03: Identify voltage disturbance events in the distribution network based on the real-time voltage monitoring data, and extract the response time difference of each first node that triggers the voltage disturbance; wherein, each first node is a node that meets the preset voltage disturbance judgment conditions.

[0031] In a preferred embodiment of this invention, the step of identifying voltage disturbance events in the distribution network based on the real-time voltage monitoring data and extracting the response time difference of each first node triggering the voltage disturbance specifically involves: After acquiring real-time voltage monitoring data from each node of the distribution network, these continuously collected voltage data are analyzed and processed in real time to identify voltage disturbance events in the distribution network. Specifically, the real-time voltage data of each node is dynamically compared with preset normal voltage operating ranges and disturbance judgment criteria. The preset normal voltage operating range is determined based on distribution network design specifications, and the disturbance judgment criteria are set with reference to national power quality standards. When the voltage data of any node exceeds the normal operating range, or when changes that conform to disturbance characteristics, such as sudden changes in voltage amplitude or phase abnormalities, occur, it can be determined that a voltage disturbance event has occurred in the distribution network. At the same time, all nodes that meet the above disturbance judgment criteria and detect voltage disturbance characteristics are defined as first nodes, and the specific time when the voltage disturbance characteristics first appear at each first node is recorded synchronously by a voltage sampling device. This time is the trigger time for each first node to trigger a voltage disturbance.

[0032] After recording the trigger times of all first nodes, the earliest trigger time is selected as the baseline time. Then, the time difference between the trigger time of each of the remaining first nodes and this baseline time is calculated. These calculated time differences represent the response time differences of each first node to the voltage disturbance. This process accurately reveals the timing differences in the responses of different first nodes to the same voltage disturbance event, providing precise and reliable timing data support for subsequent disturbance source localization analysis based on timing characteristics.

[0033] Specifically, at each first node i Deploy voltage sampling devices to collect data in real time. When any first node satisfies the preset disturbance judgment condition. If a voltage disturbance occurs, that moment is considered the disturbance trigger moment and recorded as such. For all first nodes, record the moment when the disturbance first exceeds the threshold, i.e., satisfy... time And calculate the response time difference. .

[0034] S04: Based on the response time difference and the preset disturbance propagation speed, combined with the electrical distance matrix, a disturbance propagation path error function is constructed, and the initial disturbance source node is determined by minimizing the error function.

[0035] In a preferred embodiment of this invention, the step of constructing a disturbance propagation path error function based on the response time difference and a preset disturbance propagation speed, combined with the electrical distance matrix, and determining the initial disturbance source node by minimizing the error function, specifically involves: After obtaining the response time difference of each first node and the electrical distance matrix between nodes in the distribution network, a preliminary analysis of the location of the disturbance source node is conducted in conjunction with the preset disturbance propagation speed. The preset disturbance propagation speed is determined based on the electrical transmission characteristics of the distribution network lines and can objectively reflect the propagation pattern of the disturbance signal in the distribution network lines.

[0036] First, candidate nodes are screened based on the response time difference of each first node. Nodes with response time differences within a preset range are included in the candidate disturbance source node set. Simultaneously, the screening is further optimized by considering the voltage jump characteristics when each node triggers a voltage disturbance, ensuring the relevance and effectiveness of the candidate node set. Then, for each candidate node in the candidate disturbance source node set, the electrical distance from the candidate node to each first node is extracted from the electrical distance matrix. Combined with a preset disturbance propagation speed, the theoretical response time of the disturbance signal propagating to each first node when the candidate node acts as a disturbance source is calculated.

[0037] Based on the difference between the theoretical response time and the actual response time, a disturbance propagation path error function is constructed. This function quantifies the deviation between the theoretical propagation path and the actual disturbance propagation path when a candidate node is used as a disturbance source. A pre-defined optimization algorithm is used to solve this error function, calculating the error function value for each candidate node in the candidate disturbance source node set. Finally, the candidate node with the smallest error function value is selected as the initial disturbance source node. This process, through comparison and optimization of theoretical calculations and actual data, can accurately identify the candidate node that best matches the actual disturbance propagation characteristics, providing a reliable foundation for the subsequent accurate verification and localization of the disturbance source.

[0038] More specifically, the steps for determining the initial disturbance source node in this application are as follows: (1) For each candidate source node k Construct the error function By minimizing Identify the initial disturbance source nodes m .

[0039] (2) Preset maximum response time threshold All response time differences Less than The node is included in the candidate source node set. : The preset maximum response time threshold is calculated based on the maximum power supply radius of the distribution network and the disturbance propagation speed. (3) Preset initial voltage jump threshold For nodes i Initial voltage jump amplitude Perform minimum threshold filtering, retaining nodes with sufficiently large changes in the candidate source node set. : The initial voltage jump amplitude is obtained by extracting the sudden change difference in voltage amplitude from the voltage data before and after the disturbance triggering time recorded by the voltage sampling device.

[0040] (4) Obtain the set of candidate source nodes and The intersection of these nodes will be used as the final candidate source node set. : (5) Calculate the error function of the final candidate source node set. The calculation formula is as follows: In the formula, k These are candidate disturbance source nodes. In response to time zone differences, Let be the electrical distance from node 𝑘 to node 𝑖. The average propagation speed of disturbance signals (voltage changes) in the distribution network is usually determined based on experience or simulation calibration of line characteristics.

[0041] (6) Selecting the error function The node with the minimum mean error m As the initial source node of the disturbance.

[0042] S05: Based on the electrical distance matrix and the preset disturbance propagation speed, the preliminary disturbance source node is verified by a preset parameter identification method to determine whether the preliminary disturbance source node is the actual disturbance source.

[0043] In a preferred embodiment of this invention, the step of verifying the preliminary disturbance source node based on the electrical distance matrix and a preset disturbance propagation speed using a preset parameter identification method, and determining whether the preliminary disturbance source node is an actual disturbance source, specifically involves: After identifying the initial disturbance source node, based on the constructed electrical distance matrix and the preset disturbance propagation speed, the validity of the initial disturbance source node is verified using a preset parameter identification method to accurately determine whether it is the actual disturbance source. Specifically, taking the initial disturbance source node as a benchmark, the electrical distance data from this node to each first node is extracted from the electrical distance matrix. Combined with the preset disturbance propagation speed, the theoretical disturbance arrival delay of the disturbance signal from the initial disturbance source node to each first node is calculated. This delay can reflect the propagation timing characteristics of the disturbance signal at the theoretical level.

[0044] Subsequently, the actual arrival time of the voltage disturbance first appearing at each first node is extracted from the real-time voltage monitoring data to ensure that the actual time-series data of each first node is accurate and traceable. For any pair of first nodes, the difference between the actual arrival time of the disturbance and the difference between the theoretical arrival time of the disturbance are calculated, and the sign consistency of these two differences is compared, i.e., the cases where the two differences are both positive, both negative, or both zero. The number of node pairs with consistent signs and the number of node pairs with inconsistent signs are counted.

[0045] Based on the statistically obtained number of consistent and inconsistent node pairs, a rank correlation coefficient is calculated using a preset parameter identification method. This coefficient quantifies the degree of matching between the theoretical propagation timeline and the actual propagation timeline. The calculated rank correlation coefficient is compared with a preset judgment threshold. If the rank correlation coefficient meets the preset threshold requirement, it indicates that the theoretical propagation law corresponding to the initial disturbance source node is highly consistent with the actual disturbance propagation law, and the initial disturbance source node is determined to be the actual disturbance source. If the preset threshold is not met, it indicates that the initial disturbance source node does not match the actual disturbance propagation characteristics, and the disturbance source localization analysis needs to be carried out again. The process should return to step S04 to re-select the candidate disturbance source node set, or return to step S03 to re-extract the response time difference to ensure localization accuracy.

[0046] More specifically, the steps in this application for determining whether the preliminary disturbance source node is an actual disturbance source are as follows: (1) Calculate the disturbance source node based on electrical distance and disturbance propagation speed. m To each first node i initial theoretical perturbation arrival delay : In the formula, Represents a node m To the node i electrical distance, This represents the average propagation speed of the disturbance signal (voltage change) in the distribution network.

[0047] (2) Extract the moment when the disturbance of each first node first exceeds the threshold from the real-time voltage monitoring data. And count the number of consistent arrival times of the disturbance. For any two first nodes ,if and If the signs are the same, they are considered consistent node pairs; if the signs are opposite, they are considered inconsistent node pairs.

[0048] (3) Count the number of consistent node pairs (A) and inconsistent node pairs (B), and calculate the rank correlation coefficient. : (4) Preset judgment threshold .like Then the node is considered m If the timing of the disturbance propagation is highly consistent with the actual disturbance source, it is determined to be the actual disturbance source; otherwise, return to step S04 to re-select the set of candidate disturbance source nodes, or return to step S03 to re-extract the response time difference to ensure the accuracy of the location.

[0049] S06: If the preliminary disturbance source node is the actual disturbance source, calculate the deviation between the theoretical disturbance arrival time and the actual disturbance arrival time of each first node, evaluate the positioning error of the preliminary disturbance source node based on the deviation, and obtain the positioning result of the actual disturbance source.

[0050] In a preferred embodiment of this example, if the initial disturbance source node is the actual disturbance source, the deviation between the theoretical disturbance arrival time and the actual disturbance arrival time of each first node is calculated. Based on the deviation, the positioning error of the initial disturbance source node is evaluated to obtain the positioning result of the actual disturbance source. Specifically: After determining the actual disturbance source node m, this application calculates the values ​​of each node. i The difference between the theoretical arrival time and the actual arrival time of the disturbance : (2) Calculate the average arrival time error of all first nodes. : After identifying the initial disturbance source node as the actual disturbance source, further positioning error assessment is conducted to improve the reliability and accuracy of the disturbance source positioning results. Specifically, based on the actual disturbance source node, and combined with the electrical distances from the actual disturbance source node to each first node in the constructed electrical distance matrix, as well as the preset disturbance propagation speed, the theoretical disturbance arrival time of the disturbance signal propagating from the actual disturbance source node to each first node is recalculated accurately to ensure a high degree of matching between the theoretical time series data and the actual disturbance propagation scenario.

[0051] Meanwhile, the actual arrival time of the voltage disturbance characteristics first detected by each first node is extracted from the real-time voltage monitoring data. The time difference between the theoretical arrival time of the disturbance and the actual arrival time of the disturbance is calculated for each first node. This difference is the disturbance time deviation of each first node, which intuitively reflects the degree of deviation between the theoretical propagation time sequence and the actual propagation time sequence.

[0052] Based on the disturbance time deviation data of all first nodes, the positioning error is statistically analyzed and evaluated: the arithmetic mean of the absolute values ​​of all disturbance time deviations is calculated and used as the average positioning error to characterize the average accuracy level of the overall positioning results; the maximum value is selected from the absolute values ​​of all disturbance time deviations as the maximum positioning error, reflecting the most extreme deviation situation in the positioning results. The average positioning error and the maximum positioning error are combined as the positioning error evaluation result, and combined with the specific location information of the actual disturbance source node in the distribution network, a complete positioning result of the actual disturbance source is finally formed.

[0053] In summary, this application, by acquiring the network topology parameters and line impedance parameters of the distribution network and combining them with real-time voltage monitoring data of each node, first constructs an equivalent impedance matrix and an electrical distance matrix, providing an accurate network model foundation for disturbance source location. This basic model accurately reflects the electrical relationships between nodes, solving the location error problem caused by inaccurate network parameters in existing technologies. Based on this, voltage disturbance events are identified using real-time voltage monitoring data, and the response time difference is extracted. A disturbance propagation path error function is constructed by combining the electrical distance matrix and a preset disturbance propagation speed. The initial disturbance source node is determined by minimizing the error function. This process utilizes the temporal characteristics of disturbance propagation, avoiding the inaccurate location problem caused by relying solely on voltage amplitude or phase difference in traditional methods. Furthermore, the initial disturbance source node is verified using a parameter identification method to ensure its authenticity. This verification step compensates for the lack of a secondary verification mechanism in existing technologies, effectively reducing the risk of false alarms and missed detections. Finally, the location error is evaluated by calculating the deviation between the theoretical and actual disturbance arrival times, obtaining accurate disturbance source location results. This process not only improves the positioning accuracy, but also enhances the robustness and adaptability of the method. This application effectively solves the problem that existing technologies cannot accurately and efficiently locate voltage disturbance sources in distribution networks.

[0054] Example 2 Please refer to Figure 2 This is a distribution network voltage disturbance source location device provided in this embodiment. In this embodiment, the distribution network voltage disturbance source location device includes an acquisition module 10, a construction module 20, an extraction module 30, a determination module 40, a judgment module 50, and a location module 60.

[0055] The acquisition module 10 is used to acquire the network topology parameters, line impedance parameters and real-time voltage monitoring data of each node of the distribution network. Module 20 is used to construct the equivalent impedance matrix between nodes of the distribution network based on the network topology parameters and line impedance parameters, and to calculate the electrical distance matrix between nodes based on the equivalent impedance matrix. Extraction module 30 is used to identify voltage disturbance events in the distribution network based on the real-time voltage monitoring data and extract the response time difference of each first node that triggers the voltage disturbance; wherein, each first node is a node that meets the preset voltage disturbance judgment conditions; The determination module 40 is used to construct a disturbance propagation path error function based on the response time difference and the preset disturbance propagation speed, combined with the electrical distance matrix, and to determine the initial disturbance source node by minimizing the error function; The judgment module 50 is used to verify the preliminary disturbance source node based on the electrical distance matrix and the preset disturbance propagation speed using a preset parameter identification method, and to determine whether the preliminary disturbance source node is an actual disturbance source. The positioning module 60 is used to calculate the deviation between the theoretical arrival time of each first node and the actual arrival time of the disturbance if the preliminary disturbance source node is the actual disturbance source, evaluate the positioning error of the preliminary disturbance source node based on the deviation, and obtain the positioning result of the actual disturbance source.

[0056] For ease of description and brevity, the embodiments of the present invention include all the implementation methods in the above embodiments of the method for locating voltage disturbance sources in power distribution networks, and will not be repeated here.

[0057] Example 3: This application provides a computer-readable storage medium, which includes a stored computer program, wherein the computer program, when running, controls the device where the computer-readable storage medium is located to execute the aforementioned method for locating voltage disturbance sources in a power distribution network. The method for locating voltage disturbance sources in a power distribution network, if implemented as a software functional unit and used as an independent product, can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0058] Example 4 This embodiment provides a computer program product, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements any one of the distribution network voltage disturbance source location methods as described in Embodiment 1.

[0059] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. A method for locating voltage disturbance sources in a power distribution network, characterized in that, include: Obtain network topology parameters, line impedance parameters, and real-time voltage monitoring data of each node in the power distribution network; Based on the network topology parameters and line impedance parameters, an equivalent impedance matrix between each node of the distribution network is constructed, and the electrical distance matrix between each node is calculated based on the equivalent impedance matrix. Based on the real-time voltage monitoring data, voltage disturbance events in the distribution network are identified, and the response time difference of each first node triggering the voltage disturbance is extracted; wherein, each first node is a node that meets the preset voltage disturbance judgment conditions; Based on the response time difference and the preset disturbance propagation speed, combined with the electrical distance matrix, a disturbance propagation path error function is constructed, and the initial disturbance source node is determined by minimizing the error function; Based on the electrical distance matrix and the preset disturbance propagation speed, the preliminary disturbance source node is verified by a preset parameter identification method to determine whether the preliminary disturbance source node is the actual disturbance source. If the initial disturbance source node is the actual disturbance source, calculate the deviation between the theoretical disturbance arrival time and the actual disturbance arrival time of each first node, evaluate the positioning error of the initial disturbance source node based on the deviation, and obtain the positioning result of the actual disturbance source.

2. The method for locating voltage disturbance sources in a power distribution network according to claim 1, characterized in that, Based on the network topology parameters and line impedance parameters, an equivalent impedance matrix is ​​constructed between each node of the distribution network. Based on this equivalent impedance matrix, the electrical distance matrix between each node is calculated. Specifically: Construct a node model that includes transformers, loads, and photovoltaic access points in the distribution network; Based on the network topology parameters and line impedance parameters, and combined with the node model, calculate the self-impedance of each node and the mutual impedance between any two nodes. Arrange all self-impedances and mutual impedances according to the node number to obtain the equivalent impedance matrix between nodes of the distribution network; Based on the resistance and reactance values ​​corresponding to each element in the equivalent impedance matrix, the electrical distance between any two nodes is calculated. Arrange the electrical distances between all nodes according to their node numbers to obtain the electrical distance matrix between nodes in the distribution network.

3. The method for locating voltage disturbance sources in a power distribution network according to claim 1, characterized in that, The step of identifying voltage disturbance events in the distribution network based on the real-time voltage monitoring data and extracting the response time difference of each first node triggering the voltage disturbance specifically involves: Real-time voltage monitoring data of each node is collected through a preset voltage sampling device. The real-time voltage monitoring data of each node is compared with the preset voltage disturbance judgment conditions. If the real-time voltage monitoring data of any node meets the voltage disturbance judgment conditions, it is determined that a voltage disturbance event has occurred in the distribution network, and the voltage disturbance trigger time of each first node that meets the voltage disturbance judgment conditions is obtained. Using the initially acquired voltage disturbance trigger time as the reference time, calculate the differences between the voltage disturbance trigger time of each remaining node in each first node and the reference time, and use each difference as the response time difference of each first node triggering the voltage disturbance.

4. The method for locating voltage disturbance sources in a power distribution network according to claim 1, characterized in that, Based on the response time difference and the preset disturbance propagation speed, combined with the electrical distance matrix, a disturbance propagation path error function is constructed, and the initial disturbance source node is determined by minimizing the error function. Specifically: The response time difference of each first node is compared with the preset maximum response time threshold, and nodes whose response time difference is less than the maximum response time threshold are selected to obtain the first candidate node set. Extract the initial voltage jump amplitude at the voltage disturbance trigger time of each first node, compare the initial voltage jump amplitude with a preset initial voltage jump threshold, and filter out nodes whose initial voltage jump amplitude is greater than the initial voltage jump threshold to obtain a second candidate node set; Obtain the intersection of the first candidate node set and the second candidate node set to obtain the candidate disturbance source node set; Based on each candidate node in the candidate disturbance source node set, extract each electrical distance from each candidate node to each first node from the electrical distance matrix; Based on the electrical distances mentioned above, and in conjunction with the preset disturbance propagation speed, the theoretical response time of each candidate node is calculated. The theoretical response time is compared with the difference between the actual response time of each candidate node to construct a disturbance propagation path error function; wherein, the error function is used to characterize the degree of deviation between the theoretical response time and the actual response time difference; Based on the disturbance propagation path error function, calculate the error function value of each candidate node in the candidate disturbance source node set, and select the candidate node with the smallest error function value as the initial disturbance source node.

5. The method for locating voltage disturbance sources in a power distribution network according to claim 1, characterized in that, The step of verifying the preliminary disturbance source node based on the electrical distance matrix and a preset disturbance propagation speed using a preset parameter identification method to determine whether the preliminary disturbance source node is the actual disturbance source is as follows: Based on the initial disturbance source node, the electrical distance from the initial disturbance source node to each first node is extracted from the electrical distance matrix; Based on the preset disturbance propagation speed, the initial theoretical disturbance arrival time of the disturbance signal from the initial disturbance source node to each first node is calculated. The initial actual disturbance arrival time of each first node is extracted from the real-time voltage monitoring data; wherein, the initial actual disturbance arrival time is the time when each first node first meets the voltage disturbance judgment condition; The rank correlation coefficient is calculated by comparing the difference between the initial actual arrival times of any two nodes with the difference between the initial theoretical arrival times of the disturbance. If the rank correlation coefficient meets the preset judgment threshold, the preliminary disturbance source node is determined to be the actual disturbance source.

6. The method for locating voltage disturbance sources in a power distribution network according to claim 1, characterized in that, If the initial disturbance source node is the actual disturbance source, the deviation between the theoretical disturbance arrival time and the actual disturbance arrival time of each first node is calculated. Based on the deviation, the positioning error of the initial disturbance source node is evaluated to obtain the positioning result of the actual disturbance source. Specifically: If the initial disturbance source node is determined to be the actual disturbance source, the theoretical disturbance arrival time of each first node is recalculated based on the initial disturbance source node, combined with the electrical distance from the initial disturbance source node to each first node in the electrical distance matrix and the preset disturbance propagation speed. The actual arrival time of each first node is extracted from the real-time voltage monitoring data. The difference between the theoretical arrival time of each first node and the actual arrival time of the disturbance is calculated to obtain the disturbance time deviation of each first node. The disturbance time deviations of all first nodes are statistically analyzed, and the arithmetic mean of all disturbance time deviations is calculated as the average positioning error. The deviation with the largest absolute value is selected from all the deviations at all disturbance times as the maximum positioning error; The average positioning error and the maximum positioning error are used as the positioning error evaluation results. Combined with the location information of the actual disturbance source node, the positioning result of the actual disturbance source is obtained.

7. A voltage disturbance source locating device for a power distribution network, characterized in that, include: The acquisition module is used to acquire network topology parameters, line impedance parameters, and real-time voltage monitoring data of each node in the distribution network. The construction module is used to construct the equivalent impedance matrix between each node of the distribution network based on the network topology parameters and line impedance parameters, and to calculate the electrical distance matrix between each node based on the equivalent impedance matrix. The extraction module is used to identify voltage disturbance events in the distribution network based on the real-time voltage monitoring data and extract the response time difference of each first node that triggers the voltage disturbance; wherein, each first node is a node that meets the preset voltage disturbance judgment conditions; The determination module is used to construct a disturbance propagation path error function based on the response time difference and a preset disturbance propagation speed, combined with the electrical distance matrix, and to determine the initial disturbance source node by minimizing the error function; The judgment module is used to verify the preliminary disturbance source node based on the electrical distance matrix and the preset disturbance propagation speed, and to determine whether the preliminary disturbance source node is the actual disturbance source. The positioning module is used to calculate the deviation between the theoretical arrival time of the disturbance and the actual arrival time of each first node if the preliminary disturbance source node is the actual disturbance source, evaluate the positioning error of the preliminary disturbance source node based on the deviation, and obtain the positioning result of the actual disturbance source.

8. The distribution network voltage disturbance source locating device according to claim 7, characterized in that, Based on the response time difference and the preset disturbance propagation speed, combined with the electrical distance matrix, a disturbance propagation path error function is constructed, and the initial disturbance source node is determined by minimizing the error function. Specifically: The response time difference of each first node is compared with the preset maximum response time threshold, and nodes whose response time difference is less than the maximum response time threshold are selected to obtain the first candidate node set. Extract the initial voltage jump amplitude at the voltage disturbance trigger time of each first node, compare the initial voltage jump amplitude with a preset initial voltage jump threshold, and filter out nodes whose initial voltage jump amplitude is greater than the initial voltage jump threshold to obtain a second candidate node set; Obtain the intersection of the first candidate node set and the second candidate node set to obtain the candidate disturbance source node set; Based on each candidate node in the candidate disturbance source node set, extract each electrical distance from each candidate node to each first node from the electrical distance matrix; Based on the electrical distances mentioned above, and in conjunction with the preset disturbance propagation speed, the theoretical response time of each candidate node is calculated. The theoretical response time is compared with the difference between the actual response time of each candidate node to construct a disturbance propagation path error function; wherein, the error function is used to characterize the degree of deviation between the theoretical response time and the actual response time difference; Based on the disturbance propagation path error function, calculate the error function value of each candidate node in the candidate disturbance source node set, and select the candidate node with the smallest error function value as the initial disturbance source node.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored computer program, wherein, when the computer program is executed, it controls the device containing the computer-readable storage medium to perform the distribution network voltage disturbance source location method as described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program or instructions, characterized in that, When the computer program or instructions are executed by the communication device, the distribution network voltage disturbance source location method as described in any one of claims 1 to 6 is implemented.

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