Modeling method and system for radial distribution network topological structure

Abstract

The invention discloses a modeling method and system for a radial power distribution network topological structure, and the method comprises the steps: constructing a topological matrix on the basis of nodes, and describing a radial topological network structure; searching columns with all elements being 0 in the topological matrix to obtain power supply nodes, and searching rows with all elements being 0 in the topological matrix to obtain terminal nodes; and continuously multiplying a certain row in the topological matrix by the topological matrix to obtain a connection relationship between a node represented by the certain row and other power flow downlink nodes, and continuously multiplying a certain column in the topological matrix by the topological matrix to obtain a connection relationship between a node represented by the certain column and other power flow upstream nodes. The topological structure, the line impedance and the load of the power distribution network are divided into three parts for independent modeling, and the digitization of the power distribution network is realized in cooperation with a related matrix algorithm.

Description

Technical Field

[0001] The present invention belongs to the technical field of power distribution and utilization, and in particular relates to a modeling method and system for a radial power distribution network topology structure. Background Art

[0002] With the rapid development of distribution networks, the precise operation and maintenance of distribution networks has received more and more attention. Traditional low-voltage management, line and substation transformation and other operation and maintenance work are mainly based on the experience of operation and maintenance personnel. The economic efficiency and effect of management and transformation cannot be accurately evaluated, which directly affects the efficient and precise operation and maintenance of distribution networks. Realizing the digitization of distribution networks through modeling is an important way to achieve precise operation and maintenance of distribution networks.

[0003] In the modeling methods of traditional node impedance (admittance) matrix, topology structure modeling and impedance (admittance) modeling are carried out simultaneously. The modeling process is complicated and the modeling efficiency is low. It requires a lot of energy and time from personnel, and the manual workload is large, making it difficult to promote and apply on a large scale. Summary of the invention

[0004] The present invention provides a radial distribution network topology modeling method and system, which are used to solve the technical problems of simultaneous topology modeling and impedance modeling, complex modeling process and low modeling efficiency.

[0005] In a first aspect, the present invention provides a method for modeling a radial distribution network topology structure, comprising: Based on the nodes, a topology matrix is ​​constructed to describe the radial topology network structure, wherein the matrix element 1 in the topology matrix represents the electrical connection relationship between the head and tail nodes containing the flow direction information, and the matrix element 0 in the topology matrix represents that there is no direct electrical connection relationship between the two nodes or the flow direction is in the reverse direction; Find the columns whose elements in the topology matrix are all 0 to obtain the power supply nodes, and find the rows whose elements in the topology matrix are all 0 to obtain the terminal nodes; A row in the topology matrix is ​​continuously multiplied with the topology matrix to obtain the connection relationship between the node represented by the row and other downstream nodes of the flow, and a column in the topology matrix is ​​continuously multiplied with the topology matrix to obtain the connection relationship between the node represented by the column and other upstream nodes of the flow.

[0006] In a second aspect, the present invention provides a modeling system for a radial distribution network topology structure, comprising: A construction module is configured to construct a topology matrix based on the nodes to describe the radial topology network structure, wherein a matrix element 1 in the topology matrix represents an electrical connection relationship between the head and tail nodes containing the flow direction information, and a matrix element 0 in the topology matrix represents that there is no direct electrical connection relationship between the two nodes or the flow direction is in the reverse direction; A search module is configured to search for columns in the topology matrix whose elements are all 0 to obtain power supply nodes, and to search for rows in the topology matrix whose elements are all 0 to obtain terminal nodes; The output module is configured to continuously multiply a row in the topology matrix with the topology matrix to obtain the connection relationship between the node represented by the row and other downstream nodes of the flow, and to continuously multiply a column in the topology matrix with the topology matrix to obtain the connection relationship between the node represented by the column and other upstream nodes of the flow.

[0007] According to a third aspect, an electronic device is provided, comprising: at least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can perform the steps of the method for modeling a radial distribution network topology structure according to any embodiment of the present invention.

[0008] In a fourth aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, wherein when the program instructions are executed by a processor, the processor executes the steps of the method for modeling a radial distribution network topology structure of any embodiment of the present invention.

[0009] The modeling method and system of the radial distribution network topology structure of the present application are based on the characteristics of the radial distribution network, and realize the digital modeling of the radial distribution network by constructing a topological matrix, an impedance vector and a load vector; based on the model, relevant algorithms are constructed to realize digital calculation of the radial network. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0011] Figure 1 A flow chart of a method for modeling a radial power distribution network topology structure provided by an embodiment of the present invention; Figure 2 A distribution network topology diagram of a specific embodiment is provided for an embodiment of the present invention; Figure 3 A structural block diagram of a modeling system for a radial power distribution network topology structure provided by an embodiment of the present invention; Figure 4 It is a schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0012] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0013] See also Figure 1 , which shows a flow chart of a modeling method for a radial distribution network topology structure of the present application.

[0014] like Figure 1 As shown, the modeling method of the radial distribution network topology structure specifically includes the following steps: Step S101, based on the nodes, construct a topology matrix to describe the radial topology network structure, wherein the matrix element 1 in the topology matrix represents the electrical connection relationship between the head and tail nodes containing the flow direction information, and the matrix element 0 in the topology matrix represents that there is no direct electrical connection relationship between the two nodes or the flow direction is in the reverse direction.

[0015] In a specific embodiment, after constructing a topological matrix based on nodes to describe the radial topological network structure, a vector table is constructed based on nodes to describe the impedance of each section of the line, and each vector element is the complex impedance value R+jX of each section of the line; a vector table is constructed based on nodes to describe the load of each node, and each vector element is the complex power P+jQ of each node.

[0016] In another specific embodiment, after constructing a topological matrix based on nodes to describe a radial topological network structure, the number of matrix elements in each column of the topological matrix whose sum is 0 is obtained; it is determined whether the number is greater than a preset threshold; if it is not greater than the preset threshold, the radial topological network structure does not contain isolated nodes or isolated line segments; if it is greater than the preset threshold, the radial topological network structure contains isolated nodes or isolated line segments.

[0017] Step S102, searching for columns whose elements are all 0 in the topology matrix to obtain power supply nodes, and searching for rows whose elements are all 0 in the topology matrix to obtain terminal nodes.

[0018] Step S103: continuously multiply a row in the topology matrix with the topology matrix to obtain the connection relationship between the node represented by the row and other downstream nodes of the flow, and continuously multiply a column in the topology matrix with the topology matrix to obtain the connection relationship between the node represented by the column and other upstream nodes of the flow.

[0019] In summary, the method of the present application, based on the characteristics of the radial distribution network, realizes the digital modeling of the radial distribution network by constructing a topological matrix, an impedance vector and a load vector; based on the model, a relevant algorithm is constructed to realize the digital calculation of the radial network.

[0020] In a specific implementation, the modeling method of the radial distribution network topology structure specifically includes: 1. Topological structure modeling; (1) Distribution network information collection: Collect information related to the topology of the radial distribution network, including node connection relationships, parameters of each line segment, and load parameters.

[0021] (2) Topological structure modeling: according to Figure 2 The simple distribution network topology structure is formed as shown in Table 1, which contains n rows and n columns, where the horizontal row numbers represent the first node i of a line section, and the vertical column numbers represent the last node j of a line section. The number "1" in the matrix represents the electrical connection relationship between the first and last nodes containing the flow direction information. For example, T(2,3)=1 means that there is a direct electrical connection relationship between nodes 2 and 3, and the flow direction is from node 2 to node 3; the number "0" in the matrix means that there is no direct electrical connection relationship between the two nodes or the flow direction is in the reverse direction, such as T(3,4)=0 means that there is no direct connection relationship between nodes 3 and 4, and T(3,2)=0 means that the flow direction between nodes 2 and 3 is from node 3 to node 2.

[0022] , (3) Line information modeling: From the radial network structure, we know that any node of the radial network has only one power source node. Define line j as the line segment between node j and its power source node, and the impedance of line j is Zj=Rj+jXj. As shown in the line impedance matrix table: , (4) Load information modeling: Define load j as the load Pj+jQj directly powered by node j, excluding the load powered by node j through other line segments. The directly powered loads of each node in the network are aggregated into an overall load to form a node load matrix table: , The node load matrix table can be used to easily obtain other forms of load data expressions, such as node active power and power factor matrix tables: , 2. Power node search; Since the power node has obvious characteristics in the topological matrix, that is, the elements of the column in the topological matrix where the power node is located are all 0, and there must be 1 in the elements of other columns, the column where the power node is located can be determined by calculating the sum of all column elements of the node matrix to be 0, that is, determining the sum of the elements of each column y. The expression is: , In the formula, is the value of the element in the i-th row and y-th column of the node topology matrix, and n is the number of rows in the node topology matrix; There is only one power node in a radial topology.

[0023] 3. Terminal node search; Since the terminal node has obvious characteristics in the topological matrix, that is, the elements of the row in the topological matrix where the terminal node is located are all 0, and there must be 1 in the elements of other rows, the row where the terminal node is located can be determined by calculating the sum of all row elements of the node matrix to be 0, that is, determining the sum of the elements of each row x. The expression is: , In the formula, is the value of the element in the xth row and jth column of the node topology matrix; There may be multiple terminal nodes in a hub-and-spoke topology.

[0024] 4. Push down the node relationship; A row i of the topological matrix represents the forward connection relationship between node i and all other nodes, and a column j represents the reverse connection relationship between node j and all its nodes. When the sum of the multiplication of the corresponding elements of a row i and a column j of the matrix is ​​1, it means that there is an intermediate node k between nodes i and j, satisfying T(i, k) = T(k, j) = 1, that is, there is an indirect forward connection relationship between nodes i and j. Based on this principle, the push-down nodes and upstream nodes of a node can be found.

[0025] Define the 4th row of the matrix as vector T4, T(4,1)=1 and T(4,5)=1, indicating that the directly pushed-down nodes of the 4th row are nodes 1 and 5; multiply the 4th row of the matrix by the original matrix, and get the values ​​of elements 2, 6, and 8 to be 1, indicating that node 4 is positively connected to nodes 2, 6, and 8 through nodes 1 and 5, that is, nodes 2, 6, and 8 are the secondary load nodes of node 4, and the expression is: , When the calculation result is further multiplied by the original matrix, the values ​​of elements 3 and 7 are "1", that is, nodes 3 and 7 are load nodes of nodes 2, 6 or 8, that is, the third-level load nodes of node 4. The expression is: , Repeat the above steps until all elements of the obtained array are 0, that is, there is no subsequent load node.

[0026] 5. Node relationship tracing Multiplying the original matrix by the third column yields element 5 with a value of 1, indicating that node 3 is reversely connected to node 5 through node 2, i.e., node 5 is the secondary power node of node 3. The expression is: , When the original matrix is ​​multiplied by the calculated result, the value of element 4 is 1, indicating that node 3 is reversely connected to node 4 through node 2 and node 5, that is, node 4 is the third-level power node of node 3. The expression is: , Repeat the above steps until all elements of the obtained array are 0, that is, there is no previous power node.

[0027] 6. Isolated node verification; In the process of topological modeling, there may be data errors and other problems that cause a node in the topological matrix to be an isolated node. It is necessary to verify and locate the isolated node through a specific method to correct the topological matrix. For a radial topological matrix model, if it contains isolated nodes or isolated segments that are not connected topologically, it must contain two or more power nodes, that is, the number of elements in each column y that sum to 0 is determined. If there are more than 1, it means that the model contains isolated nodes or isolated segments.

[0028] 7. Ring network verification method In the process of topology modeling, there may be data errors and other problems that cause the topology matrix to be a ring network structure. It is necessary to verify and locate the ring network nodes through specific methods to correct the topology matrix. For a radial topology matrix model, such as when it contains a topology ring network, there must be a node containing two power nodes, and the sum of a column in the matrix is ​​greater than 1, that is: .

[0029] See also Figure 3 , which shows a structural block diagram of a modeling system for a radial distribution network topology structure of the present application.

[0030] like Figure 3 As shown, the modeling system 200 of the radial power distribution network topology structure includes a construction module 210 , a search module 220 and an output module 230 .

[0031] The construction module 210 is configured to construct a topology matrix based on the nodes to describe the radial topology network structure, wherein the matrix element 1 in the topology matrix represents the electrical connection relationship between the head and tail nodes containing the flow direction information, and the matrix element 0 in the topology matrix represents that there is no direct electrical connection relationship between the two nodes or the flow direction is in the reverse direction; A search module 220 is configured to search for columns in the topology matrix whose elements are all 0 to obtain power supply nodes, and to search for rows in the topology matrix whose elements are all 0 to obtain terminal nodes; The output module 230 is configured to continuously multiply a row in the topology matrix with the topology matrix to obtain the connection relationship between the node represented by the row and other downstream nodes of the flow, and to continuously multiply a column in the topology matrix with the topology matrix to obtain the connection relationship between the node represented by the column and other upstream nodes of the flow.

[0032] It should be understood that Figure 3 Modules and references documented in Figure 1 Therefore, the operations and features described above for the method and the corresponding technical effects are also applicable to Figure 3 The modules in it will not be described in detail here.

[0033] In some other embodiments, the embodiments of the present invention further provide a computer-readable storage medium having a computer program stored thereon, wherein when the program instructions are executed by a processor, the processor executes the modeling method of the radial distribution network topology structure in any of the above method embodiments; As an implementation mode, the computer-readable storage medium of the present invention stores computer-executable instructions, and the computer-executable instructions are configured as follows: Based on the nodes, a topology matrix is ​​constructed to describe the radial topology network structure, wherein the matrix element 1 in the topology matrix represents the electrical connection relationship between the head and tail nodes containing the flow direction information, and the matrix element 0 in the topology matrix represents that there is no direct electrical connection relationship between the two nodes or the flow direction is in the reverse direction; Find the columns whose elements in the topology matrix are all 0 to obtain the power supply nodes, and find the rows whose elements in the topology matrix are all 0 to obtain the terminal nodes; A row in the topology matrix is ​​continuously multiplied with the topology matrix to obtain the connection relationship between the node represented by the row and other downstream nodes of the flow, and a column in the topology matrix is ​​continuously multiplied with the topology matrix to obtain the connection relationship between the node represented by the column and other upstream nodes of the flow.

[0034] The computer-readable storage medium may include a program storage area and a data storage area, wherein the program storage area may store an operating system and application programs required for at least one function; the data storage area may store data created according to the use of the modeling system of the radial distribution network topology structure, etc. In addition, the computer-readable storage medium may include a high-speed random access memory, and may also include a memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the computer-readable storage medium may optionally include a memory remotely arranged relative to the processor, and these remote memories may be connected to the modeling system of the radial distribution network topology structure via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0035] Figure 4 is a schematic diagram of the structure of an electronic device provided by an embodiment of the present invention, such as Figure 4 As shown, the device includes: a processor 310 and a memory 320. The electronic device may also include: an input device 330 and an output device 340. The processor 310, the memory 320, the input device 330 and the output device 340 may be connected via a bus or other means. Figure 4 In the example, the connection through the bus is taken as an example. The memory 320 is the above-mentioned computer-readable storage medium. The processor 310 executes various functional applications and data processing of the server by running the non-volatile software programs, instructions and modules stored in the memory 320, that is, the modeling method of the radial distribution network topology structure of the above-mentioned method embodiment is realized. The input device 330 can receive input digital or character information, and generate key signal input related to user settings and function control of the modeling system of the radial distribution network topology structure. The output device 340 may include a display device such as a display screen.

[0036] The electronic device can execute the method provided by the embodiment of the present invention, and has the functional modules and beneficial effects corresponding to the execution method. For technical details not described in detail in this embodiment, please refer to the method provided by the embodiment of the present invention.

[0037] As an implementation mode, the electronic device is applied to a modeling system of a radial distribution network topology structure, and is used for a client, and includes: at least one processor; and a memory connected to the at least one processor in communication; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can: Based on the nodes, a topology matrix is ​​constructed to describe the radial topology network structure, wherein the matrix element 1 in the topology matrix represents the electrical connection relationship between the head and tail nodes containing the flow direction information, and the matrix element 0 in the topology matrix represents that there is no direct electrical connection relationship between the two nodes or the flow direction is in the reverse direction; Find the columns whose elements in the topology matrix are all 0 to obtain the power supply nodes, and find the rows whose elements in the topology matrix are all 0 to obtain the terminal nodes; A row in the topology matrix is ​​continuously multiplied with the topology matrix to obtain the connection relationship between the node represented by the row and other downstream nodes of the flow, and a column in the topology matrix is ​​continuously multiplied with the topology matrix to obtain the connection relationship between the node represented by the column and other upstream nodes of the flow.

[0038] Through the description of the above implementation modes, those skilled in the art can clearly understand that each implementation mode can be implemented by means of software plus a necessary general hardware platform, or of course by hardware. Based on such an understanding, the above technical solution can essentially or in other words be embodied in the form of a software product that contributes to the prior art. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods of each embodiment or some parts of the embodiment.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A modeling method for a radial distribution network topology structure, characterized in that: include: Based on the nodes, a topology matrix is ​​constructed to describe the radial topology network structure, wherein the matrix element 1 in the topology matrix represents the electrical connection relationship between the head and tail nodes containing the flow direction information, and the matrix element 0 in the topology matrix represents that there is no direct electrical connection relationship between the two nodes or the flow direction is in the reverse direction; Find the columns whose elements in the topology matrix are all 0 to obtain the power supply nodes, and find the rows whose elements in the topology matrix are all 0 to obtain the terminal nodes; A row in the topology matrix is ​​continuously multiplied with the topology matrix to obtain the connection relationship between the node represented by the row and other downstream nodes of the flow, and a column in the topology matrix is ​​continuously multiplied with the topology matrix to obtain the connection relationship between the node represented by the column and other upstream nodes of the flow.

2. The modeling method of a radial distribution network topology structure according to claim 1, characterized in that: After constructing a topology matrix based on the nodes to describe the radial topology network structure, the method further includes: Based on the nodes, a vector table is constructed to describe the impedance of each section of the line. Each vector element is the complex impedance value R+jX of each section of the line. Based on the nodes, a vector table is constructed to describe the load of each node, and each vector element is the complex power P+jQ of each node.

3. The modeling method of a radial distribution network topology structure according to claim 1, characterized in that: After constructing a topology matrix based on the nodes to describe the radial topology network structure, the method further includes: Obtain the number of matrix elements in each column of the topology matrix whose sum is 0; Determining whether the number is greater than a preset threshold; If it is not greater than the preset threshold, the radial topology network structure does not contain isolated nodes or isolated line segments; If it is greater than a preset threshold, the radial topology network structure contains isolated nodes or isolated line segments.

4. A modeling system for radial distribution network topology, characterized in that: include: A construction module is configured to construct a topology matrix based on the nodes to describe the radial topology network structure, wherein a matrix element 1 in the topology matrix represents an electrical connection relationship between the head and tail nodes containing the flow direction information, and a matrix element 0 in the topology matrix represents that there is no direct electrical connection relationship between the two nodes or the flow direction is in the reverse direction; A search module is configured to search for columns in the topology matrix whose elements are all 0 to obtain power supply nodes, and to search for rows in the topology matrix whose elements are all 0 to obtain terminal nodes; The output module is configured to continuously multiply a row in the topology matrix with the topology matrix to obtain the connection relationship between the node represented by the row and other downstream nodes of the flow, and to continuously multiply a column in the topology matrix with the topology matrix to obtain the connection relationship between the node represented by the column and other upstream nodes of the flow.

5. An electronic device, characterized in that: include: At least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the method described in any one of claims 1 to 3.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 3 is implemented.

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