Line loss positioning method and device based on current phase identification

Abstract

The invention discloses a line loss positioning method and device based on current phase identification, and the method comprises the following steps: S1, collecting the electrical parameters of each node in a target area, and uploading the electrical parameters to a data processing device; s2, the data processing device calculates and obtains the current phase difference delta theta between the nodes, and constructs a current phase difference matrix; s3, the data processing device calculates the relevance among the nodes based on the current phase difference matrix, and determines the topological relation of the nodes in the transformer area according to the relevance; and S4, line loss positioning: when the transformer area line loss is abnormal, line loss calculation is carried out on each branch to determine the level of an abnormal branch and the level of an abnormal node, and finally the abnormal node in the level is positioned step by step, the line loss checking efficiency is remarkably improved through step-by-step positioning of the four levels, the relevance between the nodes is calculated by using the phase difference, and the line loss checking accuracy is improved. The topology accuracy is effectively improved, and the line loss positioning precision is improved.

Description

Technical Field

[0001] This invention relates to the field of power distribution information technology, and in particular to a method and apparatus for locating line losses based on current phase identification. Background Technology

[0002] Line loss refers to the energy loss in a power system caused by physical characteristics or management factors during transmission, distribution, and conversion. This loss is mainly manifested as the difference between the electrical energy output at the power supply end (e.g., transformer) and the electrical energy actually received at the user end. A distribution area typically contains a multi-level structure, from the transformer to the branch box, then to the meter box, and finally to the user end.

[0003] However, manually maintaining such multi-level topology relationships is prone to errors. Especially after power grid upgrades, topology updates often lag, leading to inaccuracies in line loss calculations. Traditional line loss analysis methods typically only calculate the overall line loss rate for a distribution area, making it difficult to accurately pinpoint anomalies at the branch line, meter box, or user level. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this invention is to provide a method and apparatus for locating line losses based on current phase identification.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A line loss location method based on current phase identification includes the following steps:

[0007] S1. Data Acquisition: Acquire electrical parameters of each node within the target area and upload the electrical parameters to the data processing device. The electrical parameters include current phase.

[0008] S2. Constructing the current phase difference matrix: The data processing device calculates the current phase difference Δθ between each node and constructs the current phase difference matrix;

[0009] S3. Constructing topology relationships: The data processing device calculates the correlation between each node based on the current phase difference matrix, and determines the topology relationship of each node in the transformer area according to its correlation. The topology relationship includes four levels in sequence: transformer area, branch, meter box, and user.

[0010] S4. Line loss location: When the line loss of the transformer area is abnormal, first calculate the line loss for each branch to determine the level of the abnormal branch and abnormal node, and finally locate the abnormal node within that level.

[0011] Furthermore, step S4 specifically includes the following steps:

[0012] S41. Branch-level location: First, calculate and obtain the line loss value of each branch, and then determine the specific abnormal branch based on the line loss value;

[0013] S42. Determine the level of the abnormal node based on the line loss value. If the line loss value belongs to the branch level of the abnormality, then the branch is determined to be an abnormal node, and the line loss location is completed. The following steps S43 and S44 are not performed. If the line loss value belongs to the meter box level of the abnormality, then step S43 is performed, and step S44 is not performed. If the line loss value belongs to the user level of the abnormality, then step S43 and S44 are performed in sequence.

[0014] S43, Box-level location: Determine the specific abnormal box under the abnormal branch;

[0015] S44. User-level location: Identify the specific abnormal user under the abnormal table box.

[0016] Furthermore, the electrical parameters mentioned in step S1 also include the user's power load curve data and the voltage of each node.

[0017] Furthermore, in step S3, the data processing device determines the correlation between the nodes by calculating the cosine similarity between them.

[0018] Furthermore, in step S41, the branches with abnormal line loss are identified by performing dynamic line loss calculations among the branches.

[0019] Furthermore, in step S43, the specific steps of meter box-level positioning include: calculating the voltage difference ΔU between each meter box and the voltage of the branch where it is located; if ΔU is greater than the rated voltage, then the meter box is determined to be an abnormal meter box.

[0020] Furthermore, in step S44, the specific steps of user-level positioning include: calculating the similarity between the real-time power load curve and the historical power load curve of each user; if the similarity is less than a predetermined value and the line loss rate increases synchronously, then the user is marked as a suspected user.

[0021] Furthermore, in step S43, the similarity between the electricity load curve in real time and in history is calculated using a dynamic time warping algorithm.

[0022] A line loss location device is provided for implementing the line loss location method based on current phase recognition described above. The device includes: several electricity meters for detecting the electrical parameters of the user-level nodes; several three-phase rail meters for detecting the electrical parameters of other nodes outside the user, and connected to the electricity meters to collect their electrical parameters; a concentrator connected to the three-phase rail meters for uploading the electrical parameters to a data processing device; and the data processing device connected to the concentrator, receiving the electrical parameters uploaded by the concentrator, constructing a current phase difference matrix and topological relationships, and performing line loss location.

[0023] Furthermore, the three-phase rail meter is equipped with a time synchronization device, which can periodically upload electrical parameters to the concentrator.

[0024] The beneficial effects of this invention are:

[0025] 1. This invention proposes a line loss location method based on current phase recognition, comprising the following steps: S1. Collecting electrical parameters of each node in the target transformer area and uploading the electrical parameters to a data processing device; S2. The data processing device calculates the current phase difference Δθ between each node and constructs a current phase difference matrix; S3. The data processing device calculates the correlation between each node based on the current phase difference matrix and determines the topological relationship of each node in the transformer area based on its correlation; S4. Line loss location: when the line loss in the transformer area is abnormal, the line loss is first calculated for each branch to determine the level of the abnormal branch and abnormal node, and finally the abnormal node is located level by level. This method improves the efficiency of line loss investigation through four levels of step-by-step location, and the correlation between nodes calculated by using phase difference can effectively increase the accuracy of topology and improve the accuracy of line loss location.

[0026] 2. The present invention proposes a line loss location method based on current phase identification. Step S4 specifically includes the following steps: S41, branch-level location: first calculate the line loss value of each branch, and then determine the specific abnormal branch based on the line loss value;

[0027] S42. Determine the level of the abnormal node based on the line loss value. If the line loss value belongs to the branch level of the abnormality, then the branch is determined to be the abnormal node, and the line loss location is completed. If the line loss value belongs to the meter box level of the abnormality, then proceed to step S43 to determine the meter box with the abnormality as the abnormal node. If the line loss value belongs to the user level of the abnormality, then proceed to steps S43 and S44 in sequence. After finding the abnormal meter box, perform the calculation again to determine the specific abnormal user and determine the user as a suspect user.

[0028] 3. The line loss location method based on current phase recognition proposed in this invention, in the specific steps of step S43, calculates the similarity between the power load curve in real time and in history through the dynamic time warping algorithm, thereby improving the accuracy of line loss location. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a flowchart of a line loss location method based on current phase recognition according to the present invention. Detailed Implementation

[0031] Example 1

[0032] The following is combined with Figure 1 The present invention will be described in detail below.

[0033] A line loss location method based on current phase identification, such as Figure 1 As shown, it includes the following steps:

[0034] S1. Data Acquisition: Acquire electrical parameters of each node within the target area and upload the electrical parameters to the data processing device. The electrical parameters include current phase.

[0035] S2. Constructing the current phase difference matrix: The data processing device calculates the current phase difference Δθ between each node and constructs the current phase difference matrix;

[0036] S3. Constructing Topology Relationships: The data processing device calculates the correlation between each node based on the current phase difference matrix, and determines the topology relationship of each node in the transformer area based on its correlation. The topology relationship includes four levels in sequence: transformer area, branch, meter box, and user.

[0037] S4. Line loss location: When the line loss in the transformer area is abnormal, first calculate the line loss for each branch to determine the level of the abnormal branch and abnormal node, and finally locate the abnormal node within that level.

[0038] Specifically, the data processing device constructs a matrix of the phase differences of the A / B / C three-phase currents of all nodes within the transformer area using a topological clustering algorithm. For example:

[0039]

[0040] The method employs a four-level hierarchical approach to improve the efficiency of line loss investigation. By utilizing phase difference calculations to determine the correlation between nodes, it effectively increases the accuracy of topology analysis and enhances the precision of line loss location. Specifically, transformer boxes manage line losses for the entire distribution area, corresponding to the distribution area level; branch boxes manage losses for branch lines, corresponding to the branch level; meter boxes manage line losses between meter and user meters, corresponding to the user level; and user boxes manage line losses at the user level.

[0041] Step S4 specifically includes the following steps:

[0042] S41. Branch-level location: First, calculate the line loss value of each branch, and then determine the specific abnormal branch based on the line loss value.

[0043] S42. Determine the level of the abnormal node based on the line loss value. If the line loss value belongs to the branch level of the abnormality, then the branch is determined to be an abnormal node, and the line loss location is completed. The following steps S43 and S44 are not performed. If the line loss value belongs to the meter box level of the abnormality, then the following step S43 is performed, but the following step S44 is not performed. If the line loss value belongs to the user level of the abnormality, then the following steps S43 and S44 are performed in sequence.

[0044] S43, Box-level location: Determine the specific abnormal box under the abnormal branch;

[0045] S44. User-level location: Identify the specific abnormal user under the abnormal table box.

[0046] In practical applications, abnormal nodes can appear at any node across the three levels: branch, meter box, and user. When abnormal line loss occurs at nodes at different levels, the detected line loss value at the branch will differ. Therefore, the abnormal line loss value at the branch level can be used to determine which level of the topology the abnormal line loss occurred at. For example, the line loss value of an abnormal node at the branch level will be greater than that at the meter box level. Therefore, when line loss is detected in a transformer area, first determine which branch the abnormal node is on, and then determine the level of the abnormal node based on the line loss value of that branch. Finally, locate the specific node within that level according to the topology. An abnormal node can be single or multiple.

[0047] When an abnormal node appears at the branch level, proceed to step S41 to perform dynamic line loss calculation on each branch. Based on the line loss value, the branch with abnormal line loss can be identified as an abnormal node.

[0048] When an abnormal node appears at the meter box level, first perform step S41 to determine the branch with abnormal line loss, and then perform step S43 for the meter boxes under that branch to determine the specific meter box with abnormal line loss and identify it as an abnormal node (high loss meter box).

[0049] When an abnormal node appears at the user level, first proceed to step S41 to determine the branch with abnormal line loss, then proceed to step S43 under the branch to determine the box with abnormal line loss, and then proceed to step S44 under the box to determine the specific user with abnormal line loss and identify it as an abnormal node.

[0050] In this embodiment, the electrical parameters in step S1 also include the user's electricity load curve data and the voltage of each node. In step S3, the data processing device determines the correlation between nodes by calculating the cosine similarity between nodes.

[0051] Specifically, S represents the cosine similarity between two nodes, and its calculation formula is:

[0052]

[0053] In this embodiment, the similarity threshold is set to 0.95. If S(i, j) > 0.95, then nodes i and j are determined to belong to the same branch or the same meter box. After confirming the correlation between all nodes, the data processing device constructs a four-level topological relationship of "transformer → branch → meter box → user" using hierarchical clustering.

[0054] In step S41, branches with abnormal line loss are identified by performing dynamic line loss calculations between branches.

[0055] In step S43, the specific steps for meter box-level positioning include: calculating the voltage difference ΔU between each meter box and the voltage of its branch; if ΔU is greater than the rated voltage, the meter box is determined to be an abnormal meter box. Specifically, if ΔU > 5% (rated voltage), it is determined to be an abnormal meter box.

[0056] In this embodiment, step S43, the specific steps of user-level positioning, include: calculating the similarity between the real-time power load curve and the historical power load curve for each user; if the similarity is less than a predetermined value and the line loss rate increases synchronously, then the user is marked as a suspected user. Further, step S43 calculates the similarity between the real-time and historical power load curves using a dynamic time warping algorithm. In this embodiment, the predetermined value is 60%. If the similarity is <60% and the line loss rate increases synchronously, then the user is marked as a suspected user, and the system production work order dispatches inspection personnel to confirm whether the user is an abnormal node.

[0057] Example 2

[0058] A line loss location device is provided to implement the line loss location method based on current phase recognition described above. It includes: several electricity meters for detecting electrical parameters of user-level nodes; several three-phase rail meters for detecting electrical parameters of other nodes outside the user's network, and connected to the electricity meters to collect their electrical parameters; a concentrator connected to the three-phase rail meters for uploading the electrical parameters to a data processing device; and the data processing device connected to the concentrator, receiving the uploaded electrical parameters, constructing a current phase difference matrix and topological relationship, and performing line loss location. The three-phase rail meters are equipped with a time synchronization device that can synchronize the time of all nodes and periodically upload electrical parameters to the concentrator. In this embodiment, the time synchronization device is a clock that can synchronize with Beijing time in real time.

[0059] Three-phase rail meters are installed on the transformer, branch box, and meter box sides to measure current phase, voltage, power, and other data at the nodes they operate on, and to collect load curve data from user meters. The three-phase rail meters also include a high-speed dual-mode communication module to facilitate the uploading of current phase data and collected user meter load curves and other electrical data. The concentrator is installed under the transformer in the distribution area, capable of collecting electrical data from all nodes within the entire distribution area and uploading the electrical data to a data processing device via a public network (such as 4G). The three-phase rail meters incorporate a Rogowski coil with an integrator, employing Rogowski coil sampling, which is simple to install and suitable for large-scale deployment.

[0060] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand and implement the present invention. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for locating line losses based on current phase recognition, characterized in that, Includes the following steps: S1. Data Acquisition: Acquire electrical parameters of each node within the target area and upload the electrical parameters to the data processing device. The electrical parameters include current phase. S2. Constructing the current phase difference matrix: The data processing device calculates the current phase difference Δθ between each node and constructs the current phase difference matrix; S3. Constructing topology relationships: The data processing device calculates the correlation between each node based on the current phase difference matrix, and determines the topology relationship of each node in the transformer area according to its correlation. The topology relationship includes four levels in sequence: transformer area, branch, meter box, and user. S4. Line loss location: When the line loss of the transformer area is abnormal, first calculate the line loss for each branch to determine the level of the abnormal branch and abnormal node, and finally locate the abnormal node within that level.

2. The line loss location method based on current phase identification as described in claim 1, characterized in that, Step S4 specifically includes the following steps: S41. Branch-level location: First, calculate and obtain the line loss value of each branch, and then determine the specific abnormal branch based on the line loss value; S42. Determine the level of the abnormal node based on the line loss value. If the line loss value belongs to the branch level of the abnormality, then determine the abnormal branch as the abnormal node, complete the line loss location, and do not perform the following steps S43 and S44. If the line loss value belongs to the meter box level of the abnormality, then perform the following step S43 and do not perform the following step S44. If the line loss value belongs to the user level of the abnormality, then perform the following steps S43 and S44 in sequence. S43, Box-level location: Determine the specific abnormal box under the abnormal branch; S44. User-level location: Identify the specific abnormal user under the abnormal table box.

3. The line loss location method based on current phase identification as described in claim 2, characterized in that, The electrical parameters mentioned in step S1 also include the user's power load curve data and the voltage of each node.

4. The line loss location method based on current phase identification as described in claim 3, characterized in that, In step S3, the data processing device determines the correlation between the nodes by calculating the cosine similarity between them.

5. A line loss location method based on current phase identification as described in claim 3 or 4, characterized in that, In step S41, the branches with abnormal line loss are identified by performing dynamic line loss calculations among the branches.

6. The line loss location method based on current phase identification as described in claim 5, characterized in that, In step S43, the specific steps of meter box level positioning include: calculating the voltage difference ΔU between each meter box and the voltage of the branch where it is located; if ΔU is greater than the rated voltage, then the meter box is determined to be an abnormal meter box.

7. The line loss location method based on current phase identification as described in claim 6, characterized in that, In step S44, the specific steps of user-level positioning include: calculating the similarity between the real-time power load curve and the historical power load curve of each user; if the similarity is less than a predetermined value and the line loss rate increases synchronously, then the user is marked as a suspected user.

8. The line loss location method based on current phase identification as described in claim 7, characterized in that, In step S43, the similarity between the real-time and historical electricity load curves is calculated using a dynamic time warping algorithm.

9. A line loss locating device, used to implement the line loss locating method based on current phase recognition as described in any one of claims 1-8, characterized in that, include: The system includes several electricity meters for detecting the electrical parameters of the user-level nodes; several three-phase rail meters for detecting the electrical parameters of other nodes besides the user, and signal-connected to the electricity meters to collect their electrical parameters; a concentrator signal-connected to the three-phase rail meters for uploading the electrical parameters to a data processing device; and the data processing device signal-connected to the concentrator, which, after receiving the electrical parameters uploaded by the concentrator, constructs a current phase difference matrix and topology relationship, and performs line loss location.

10. A line loss location device based on current phase recognition as described in claim 9, characterized in that, The three-phase rail meter is equipped with a time synchronization device, which can upload electrical parameters to the concentrator at regular intervals.

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