G3-PLC communication characteristic-based power distribution network area physical topology identification method

Abstract

The invention is suitable for the technical field of intelligent power grids, and relates to a G3-PLC communication characteristic-based power distribution network area physical topology identification method, which comprises the following steps of: S10, constructing a power distribution network area physical topological graph model; s20, determining an edge weight in the physical topological graph model of the distribution network area; s30, improving and constraining a minimum spanning tree (MST) based on a Prim algorithm of G3-PLC communication characteristics, and improving a Prim algorithm flow; and S40, identifying the physical topological structure of the power distribution network area. The method is simple in process and convenient to operate, on the basis of not adding extra hardware equipment and any manual operation, the weighted graph is constructed through G3-PLC communication data, the minimum spanning tree (MST) is generated through the Prim algorithm, the physical topological structure of the power distribution network area is recognized, and the recognition accuracy is high.

Description

Technical Field

[0001] The present invention belongs to the technical field of smart grids, and in particular to a method for identifying the physical topology of a distribution network area based on G3-PLC communication characteristics. Background Art

[0002] The physical topology of a distribution network refers to the physical connection and hierarchical relationships between various devices in the distribution network (such as transformers, switches, lines, smart meters, etc.). Accurately identifying the physical topology of the distribution network is very important for the stable operation of the power system.

[0003] Traditional distribution network physical topology identification is mainly based on the following methods: manual inspection: recording equipment connection relationships through manual inspection, which is suitable for small-scale distribution networks, but it is inefficient and prone to errors; drawing comparison: using design drawings or historical data for comparison, but the drawings may be outdated or inaccurate; characteristic current injection method: by installing characteristic current injection devices at each branch and end of the distribution network, the characteristic current is injected into the distribution network, and then the characteristic current is sent in turn through each device to identify the various branches and levels of the distribution network. Although this method can accurately identify the physical topology of the distribution network, it requires the installation of corresponding characteristic current injection devices on the existing distribution network. It does not have the characteristics of intelligence, dynamic adjustment, and dynamic identification, and is not feasible for engineering implementation. The patent with announcement number CN118801381B provides a method, device and terminal for identifying substation topology of low-frequency characteristic current, including: in response to the identification of the substation topology, sending low-frequency characteristic current signals to each phase of the multi-phase line in the substation topology in a time-sharing manner, and recording the first information of sending the low-frequency characteristic current signals; determining the target sending devices downstream of each concentrator according to the files of the downstream sending devices in the concentrator; calling the receiving events of the target sending devices downstream of each concentrator for the low-frequency characteristic current signals, wherein the receiving events include the second information of the low-frequency characteristic current signals recorded by the target sending devices; when the calling tests are completed for each concentrator, the first information and the second information are used for multi-level topology classification according to the principle of similarity to obtain the substation topology identification results. This patent topology identification method also adopts the characteristic current injection method, and has the same disadvantages as the prior art.

[0004] Therefore, how to provide a method for identifying the physical topology of a distribution network area that is easy to operate, does not require additional hardware equipment, and has high recognition accuracy is an urgent problem to be solved by personnel in this technical field. Summary of the invention

[0005] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a method for identifying the physical topology of a distribution network substation based on G3-PLC communication characteristics, so as to solve the problems of cumbersome operation of identifying the physical topology of the substation in the prior art, the need to add additional equipment, and relatively low identification accuracy.

[0006] To solve the above technical problems, the present invention adopts the following technical solutions:

[0007] The present invention provides a method for identifying the physical topology of a distribution network substation based on G3-PLC communication characteristics, including the following steps:

[0008] S10. Construct a physical topology map model of the distribution network substation;

[0009] S20. Determine the edge weights in the physical topology map model of the distribution network substation;

[0010] S30. Improve the Prim algorithm based on G3-PLC communication characteristics and the constrained minimum spanning tree MST, and improve the Prim algorithm process;

[0011] S40. Identify the physical topology structure of the distribution network substation.

[0012] Further, in the step S10, the physical topology map model of the distribution network substation includes: a node set V, an edge set E, and edge weights , the node set V includes transformers, intelligent electricity meters with G3-PLC communication modules, and branch boxes, the edge set E includes all possible candidate edges for physical connections, and the edge weights The smaller the weight, the higher the possibility of physical connection.

[0013] Further, in the step S20, the edge weights The calculation formula is as follows: ;

[0014] Where , is the G3-PLC signal attenuation, , is the G3-PLC transmission power, , is the signal strength from node i to j; , is the G3-PLC signal delay distance, , is the propagation delay of the signal from node i to j; , is the minimum routing hop count of G3-PLC communication, , , are the minimum routing hop counts of nodes i and j to the transformer root node; LQI is the signal quality of the G3-PCL communication node.

[0015] Further, the calculation formula for the signal quality LQI of each node of G3-PLC is as follows:

[0016] LQI = (SNR + 10) × 255 / (53.75 + 10) = (SNR + 10) × 4;

[0017] Where SNR is the signal - to - noise ratio of node i.

[0018] Furthermore, the normalization coefficients are as follows: ; ; ; .

[0019] Furthermore, , where , , , .

[0020] Furthermore, the specific steps of step S30 are as follows:

[0021] S301. Initialization: Select the transformer node r as the root, add it to the tree node set , the edge set , initialize the priority queue Q, store all the edges connected to the node r, and sort them in ascending order;

[0022] S302. Iterative expansion: Take out the edge with the smallest weight from Q, where , , if , then add v to T, the edge add it to the edge set , add the new adjacent edges of v to Q;

[0023] S303. Termination condition: All nodes are added to T, generating the tree .

[0024] Furthermore, in step S40, the physical topology structure satisfies radial acyclic, hierarchical consistency, voltage drop constraint, and power constraint.

[0025] Compared with the prior art, the physical topology identification method for the distribution network sub - station area based on G3 - PLC communication characteristics provided by the present invention has at least the following beneficial effects:

[0026] Traditional methods for identifying the physical topology of distribution networks are cumbersome to operate and have low accuracy, requiring the installation of corresponding characteristic current injection devices in existing distribution networks. The process of the present invention is simple and convenient to operate. Without adding additional hardware devices and any manual operations, a weighted graph is constructed through G3-PLC communication data (RSSI, time delay, optimal routing hop count), and a minimum spanning tree (MST) is generated through the Prim algorithm to identify the physical topology structure of the distribution network area, meeting the constraints of radial, loop-free, and hierarchical, with high identification accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the solution of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0028] Figure 1 It is a flowchart of the method for identifying the physical topology of a distribution network area based on G3-PLC communication characteristics provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. The preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0031] The present invention provides a method for identifying the physical topology of a distribution network area based on G3-PLC communication characteristics, which is applied to the identification process of the physical topology structure (physical connection relationship and hierarchical relationship) of each device (transformer, switch, line, smart electricity meter) in the distribution network. The method for identifying the physical topology of the distribution network area includes the following steps:

[0032] S10. Construct a physical topology graph model of the distribution network area;

[0033] S20. Determine the edge weights in the physical topology graph model of the distribution network area;

[0034] S30. Improve the Prim algorithm and constrain the minimum spanning tree MST based on G3-PLC communication characteristics, and improve the Prim algorithm process;

[0035] S40. Identify the physical topology structure of the distribution network substation area.

[0036] The process of the present invention is simple and convenient to operate. Without adding additional hardware devices and any manual operations, a weighted graph is constructed through G3-PLC communication data, and a minimum spanning tree (MST) is generated through the Prim algorithm to identify the physical topology structure of the distribution network substation area, with high identification accuracy.

[0037] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0038] The present invention provides a method for identifying the physical topology of a distribution network substation area based on G3-PLC communication characteristics, which is applied to the identification process of the physical topology structure (physical connection relationship and hierarchical relationship) of various devices (transformers, switches, lines, smart electricity meters) in the distribution network, such as Figure 1 As shown, in this embodiment, the method for identifying the physical topology of the distribution network substation area includes the following steps:

[0039] S10. Construct a physical topology graph model of the distribution network substation area.

[0040] Specifically, in this embodiment, the physical topology graph model of the distribution network substation area includes:

[0041] Node set V: Devices such as transformers (root node r), smart electricity meters with G3-PLC communication modules, and branch boxes, a total of N nodes.

[0042] Edge set E: All possible candidate edges for physical connections.

[0043] Edge weight : The weight synthesizes G3-PLC communication characteristics, and the smaller the value, the higher the possibility of physical connection.

[0044] S20. Determine the edge weights in the physical topology graph model of the distribution network substation area.

[0045] Specifically, in this embodiment, the edge weight The calculation formula is as follows: ;

[0046] Where , is the G3-PLC signal attenuation, , is the G3-PLC transmit power (dBm), , is the signal strength from node i to j; ( ), is the G3-PLC signal delay distance, is the propagation delay of the signal from node i to j; , is the minimum number of routing hops for G3-PLC communication, 、 are the minimum number of routing hops from nodes i and j to the transformer root node; LQI is the signal quality of the G3-PCL communication node.

[0047] Furthermore, in this embodiment, the calculation formula for the signal quality LQI of each node in G3-PLC is as follows:

[0048] LQI = (SNR + 10) × 255 / (53.75 + 10) = (SNR + 10) × 4;

[0049] where SNR is the signal-to-noise ratio of node i.

[0050] Furthermore, in this embodiment, the normalization coefficients are as follows: ; ; ; .

[0051] Furthermore, in this embodiment, , where , , , .

[0052] S30. Improve the Prim algorithm and the constrained minimum spanning tree MST based on the G3-PLC communication characteristics, and improve the Prim algorithm process.

[0053] Specifically, in this embodiment, the specific steps of step S30 are as follows:

[0054] S301. Initialization:

[0055] Select the transformer node r as the root and add it to the tree node set , and the edge set .

[0056] Initialize the priority queue Q to store all the edges connected to the node r, and sort them in ascending order.

[0057] S302. Iterative expansion:

[0058] Loop: Take out the edge with the smallest weight from Q , where , .

[0059] Hierarchy check: If , then add v to T, and add the edge to the edge set .

[0060] Update the queue: Add the new adjacent edges of v to Q.

[0061] S303. Termination condition: All nodes are added to T, and a spanning tree is generated.

[0062] S40. Identify the physical topology of the distribution network substation area.

[0063] Further, in this embodiment, the constraint conditions are as follows:

[0064] Radial and acyclic: Since the distribution network topology is a tree structure, the generated is a tree structure, meeting .

[0065] Hierarchical consistency: The level number of the child node is the level of the parent node plus 1. The hop count of the child node ( ).

[0066] Voltage drop constraint: , ( ).

[0067] Power constraint: , if it violates the rule, remove the edge , and re-run the Prim algorithm to generate a subtree.

[0068] Compared with the prior art, the physical topology identification method of the distribution network substation area based on G3-PLC communication characteristics described in the above embodiment has a traditional physical topology identification method of the distribution network that is cumbersome to operate and has low accuracy, and requires the installation of corresponding characteristic current injection devices for the existing distribution network. The process of the present invention is simple and convenient to operate. Without adding additional hardware devices and any manual operations, a weighted graph is constructed through G3-PLC communication data (RSSI, delay, optimal routing hop count), and a minimum spanning tree (MST) is generated through the Prim algorithm to identify the physical topology of the distribution network substation area, meeting the radial, acyclic, and hierarchical constraints, and having high identification accuracy.

[0069] Obviously, the embodiments described above are only the preferred embodiments of the present invention, rather than all embodiments. The preferred embodiments of the present invention are given in the accompanying drawings, but they do not limit the patent scope of the present invention. The present invention can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosed content of the present invention more thorough and comprehensive. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing specific embodiments, or perform equivalent replacements for some of the technical features. Any equivalent structures directly or indirectly using the content of the specification and drawings of the present invention in other related technical fields are equally within the scope of the patent protection of the present invention.

Claims

1. A method for identifying the physical topology of a distribution network substation based on the communication characteristics of G3-PLC, characterized in that Including the following steps: S10. Constructing the physical topology graph model of the distribution network substation area; S20. Determining the edge weights in the physical topology graph model of the distribution network substation area; In the step S20, the edge weight is calculated according to the following formula: ； Among them , is the G3-PLC signal attenuation , is the G3-PLC transmit power , is the signal strength from node i to j , is the G3-PLC signal delay distance , is the propagation delay of the signal from node i to j , is the minimum routing hop count of G3-PLC communication 、 , are the minimum routing hop counts from nodes i and j to the transformer root node; LQI is the signal quality of the G3-PCL communication node S30. Improving the Prim algorithm based on the G3-PLC communication characteristics and the constrained minimum spanning tree MST, and improving the Prim algorithm process; S40. Identifying the physical topology structure of the distribution network substation area.

2. The method for identifying the physical topology of a distribution network substation area based on G3-PLC communication characteristics according to claim 1, wherein In the step S10, the physical topology diagram model of the distribution network substation area includes: a node set V, an edge set E, and edge weights , the node set V includes transformers, smart electricity meters with G3-PLC communication modules, and branch boxes, the edge set E includes all possible candidate edges for physical connections, and the edge weights The smaller the weight, the higher the possibility of physical connection.

3. The method for identifying the physical topology of a distribution network substation based on G3-PLC communication characteristics according to claim 1, wherein The calculation formula for the signal quality LQI of each node of G3-PLC is as follows: LQI = (SNR + 10) × 255 / (53.75 + 10) = (SNR + 10) × 4; where SNR is the signal-to-noise ratio of node i.

4. The method for identifying the physical topology of a distribution network substation based on G3-PLC communication characteristics according to claim 3, wherein The normalization coefficient is as follows: ； ； ； 。 5. The method for identifying the physical topology of a distribution network substation based on G3-PLC communication characteristics according to claim 4, wherein , where , , , .

6. The method for identifying the physical topology of a distribution network substation based on G3-PLC communication characteristics according to claim 1, wherein The specific steps of the said step S30 are as follows: S301. Initialization: Select the transformer node r as the root and add it to the tree node set , the edge set . Initialize the priority queue Q to store all the edges connected to the node r, and sort them in ascending order; S302. Iterative expansion: Take out the edge with the smallest weight from Q , where , , if , then add v to T, and add the edge to the edge set , and add the new adjacent edges of v to Q; S303. Termination condition: all nodes join T to generate a spanning tree .

7. The method for identifying the physical topology of a distribution network substation based on G3-PLC communication characteristics according to claim 1, wherein In the said step S40, the physical topology structure satisfies radial acyclicity, hierarchical consistency, voltage drop constraint, and power constraint.

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