Partition-based meshed transmission and distribution network optimization method and system

Abstract

The present invention relates to the field of power grid zoning control, and provides a method and system for optimizing a meshed transmission and distribution network based on zoning, including: S1: obtaining a mesh network topology of the power grid, setting the number of regions to be divided, and determining a common transmission line set in the mesh network topology; S2: determining a boundary bus set in the mesh network topology through the common transmission line set, partitioning the mesh network topology through the boundary bus set and the number of regions, and obtaining multiple regions; S3: constructing an optimization framework through each of the regions, the common transmission line set, and the boundary bus set; S4: regulating and optimizing the power grid through the optimization framework. The present invention can improve the robustness of the power grid, and establishes a new optimization framework based on the regional division of the mesh power grid network topology, which is suitable for problems such as flow control, voltage control, and fault handling.

Description

Technical Field

[0001] The present invention relates to the field of power grid zoning control, and in particular to a zoning-based meshed transmission and distribution grid optimization method and system. Background Art

[0002] The widespread integration of new energy sources has increased the scale of the power grid, but also brought more uncertainty. Geographical location and energy distribution have forced operators or power utilities to invest more money in controlling the stability and safety of electricity. In order to improve the reliability of the power grid and reduce operating costs, researchers have proposed the concept of zoning control.

[0003] The traditional partition control concept and framework are mainly aimed at radial distribution network systems, whose network topology is simple and easy to control, and the zones are connected by a single transmission line. In reality, radial network topology is mostly non-important areas with single power supply. For important distribution areas with multi-circuit power supply, the power transmission network topology is generally ring or mesh. For the transmission system, in order to improve the reliability of the transmission network and rationally use energy, its network topology is mostly mesh. The complexity of its transmission line and bus connection is much higher than that of the traditional radial network. In terms of optimization framework, there is only one common transmission line connecting the radial network zones after partitioning. The optimization framework established based on this is relatively simple, but its scope of application is relatively small. It is basically not applicable to the actual power grid network topology, especially the transmission network with high voltage level and large transmission capacity. Once there is a problem with the regional connection line, it will affect the safe operation of the entire power grid, and it is not conducive to timely troubleshooting, which may cause serious economic losses.

[0004] The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are prior art. Summary of the invention

[0005] In order to solve the technical problems existing in the prior art such as narrow application scope, poor robustness, and wide impact range of common transmission line failure, the present invention provides a partition-based meshed transmission and distribution network optimization method, comprising:

[0006] S1: obtaining a mesh network topology diagram of the power grid, setting the number of regions to be divided, and determining a set of common transmission lines in the mesh network topology diagram;

[0007] S2: determining a boundary bus set in the mesh network topology map by using the common transmission line set, and partitioning the mesh network topology map by using the boundary bus set and the number of regions to obtain a plurality of regions;

[0008] S3: constructing an optimization framework through each of the regions, the common transmission line set and the boundary bus set;

[0009] S4: Optimizing and regulating the power grid through the optimization framework.

[0010] Preferably, step S1 specifically comprises:

[0011] S11: setting the number of regions to be divided to k;

[0012] S12: Acquire all transmission lines in the mesh network topology diagram;

[0013] S13: Obtain the transmission capacity of each transmission line;

[0014] S14: selecting the first 3k or 4k transmission lines with the largest transmission capacity as common transmission lines;

[0015] S15: The set of all common transmission lines is taken as the common transmission line set.

[0016] Preferably, step S2 specifically comprises:

[0017] S21: Acquire all buses in the mesh network topology diagram;

[0018] S22: In the common transmission line set, the busbars at both ends of each common transmission line are taken as boundary busbars, and the set of all boundary busbars is taken as the boundary busbar set;

[0019] S23: According to the number of regions, the mesh network topology diagram is cut along each boundary bus to obtain a plurality of regions, each of which needs to have at least one power regulation unit.

[0020] Preferably, step S3 specifically comprises:

[0021] S31: The area containing both the boundary bus and the public transmission line is regarded as the public area, and the rest of the area is regarded as the non-public area;

[0022] S32: The formula of the optimization framework is:

[0023]

[0024] stΦ(X CHANGE )=0,

[0025] Ω(X CHANGE )≤0,

[0026] Ψ(X0)=0,

[0027]

[0028] Among them, X CHANGrepresents the adjustable part in the mesh network topology, specifically the physical quantity in the adjustable device in the public area, the public transmission line set and the boundary bus set; X0 represents the non-adjustable part in the mesh network topology, specifically the physical quantity in the non-public area; φ(X CHANGE ) represents the optimization objective function of the public area, φ(X0) represents the optimization objective function of the non-public area, Φ(X CHANGE )=0 is the equality constraint of the common area; Ω(X CHANGE )≤0 is the inequality constraint of the public region; Ψ(X0)=0 is the equality constraint of the non-public region; is the inequality constraint for the non-common region.

[0029] A partition-based meshed transmission and distribution network optimization system, comprising:

[0030] A common transmission line set acquisition module, used to acquire a mesh network topology diagram of the power grid, set the number of areas to be divided, and determine a common transmission line set in the mesh network topology diagram;

[0031] A region partitioning module, used to determine a boundary bus set in the mesh network topology map through the common transmission line set, and partition the mesh network topology map through the boundary bus set and the number of regions to obtain a plurality of regions;

[0032] An optimization framework building module, used for building an optimization framework through each of the regions, the common transmission line set and the boundary bus set;

[0033] The regulation module is used to regulate and optimize the power grid through the optimization framework.

[0034] The present invention has the following beneficial effects:

[0035] 1. Selecting transmission lines with large transmission capacity as public transmission lines improves the robustness of the power grid system;

[0036] 2. A new optimization framework is established based on the mesh network topology partitioning of the power grid. The research focus of this optimization framework is on the boundary bus set and the public transmission line set, which reduces the complexity of the optimization problem. The proposed framework is relatively universal and suitable for problems such as power flow control, voltage control, and fault handling. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a flow chart of a method according to an embodiment of the present invention;

[0038] Figure 2 It is the mesh network topology diagram of IEEE-24 node system;

[0039] Figure 3 A schematic diagram of the partitioning of a mesh network topology diagram;

[0040] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0041] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0042] Reference Figure 1 The present invention provides a partition-based mesh transmission and distribution network optimization method, focusing on the partition of the mesh transmission and distribution network. Compared with the traditional radial network topology partition, the mesh network topology partition is more in line with the actual power grid topology structure, and a partition method for connecting multiple transmission lines between regions is proposed. Since the transmission line with large transmission capacity has a higher safety level, the transmission line with large transmission capacity is selected as the public transmission line, thereby improving the robustness of the system;

[0043] A new optimization framework is established based on the mesh network topology partition of the power grid. The research focus of this optimization framework is the boundary bus set and the public transmission line set, which reduces the complexity of the optimization problem. The proposed framework is relatively universal and is applicable to problems such as power flow control, voltage control, and fault handling.

[0044] Specifically include:

[0045] S1: obtaining a mesh network topology diagram of the power grid, setting the number of regions to be divided, and determining a set of common transmission lines in the mesh network topology diagram;

[0046] S2: determining a boundary bus set in the mesh network topology map by using the common transmission line set, and partitioning the mesh network topology map by using the boundary bus set and the number of regions to obtain a plurality of regions;

[0047] S3: constructing an optimization framework through each of the regions, the common transmission line set and the boundary bus set;

[0048] S4: Optimizing and regulating the power grid through the optimization framework.

[0049] In this embodiment, step S1 is specifically as follows:

[0050] S11: setting the number of regions to be divided to k;

[0051] S12: Acquire all transmission lines in the mesh network topology diagram;

[0052] S13: Obtain the transmission capacity of each transmission line;

[0053] S14: selecting the first 3k or 4k transmission lines with the largest transmission capacity as common transmission lines;

[0054] S15: The set of all common transmission lines is taken as the common transmission line set.

[0055] refer to Figure 2 In the specific implementation, taking the IEEE-24 node system as an example, the number of regions is set to 3, and the first 9 transmission lines with the largest transmission capacity are used as public transmission lines. The obtained public transmission line set is:

[0056] LINE={L 15-21 ,L 16-14 ,L 16-19 ,L 17-22 ,L 18-21 ,L 3-24 ,L 9-11 ,L 10-11 ,L 10-12}

[0057] Among them, L n-m Represents a transmission line, and n and m are the bus numbers.

[0058] In this embodiment, step S2 is specifically as follows:

[0059] S21: Acquire all buses in the mesh network topology diagram;

[0060] S22: In the common transmission line set, the busbars at both ends of each common transmission line are taken as boundary busbars, and the set of all boundary busbars is taken as the boundary busbar set;

[0061] S23: According to the number of regions, the mesh network topology diagram is cut along each boundary bus to obtain a plurality of regions, each of which needs to have at least one power regulation unit.

[0062] refer to Figure 3 , the obtained boundary bus set is:

[0063] BUS={N3,N9,N 10 ,N 11 ,N 12 ,N 14 ,N 15 ,N 16 ,N 17 ,N 18 ,N 19 ,N 21 ,N 22 ,N 24}

[0064] Among them, N n represents the bus, n is the bus number;

[0065] Divide the mesh network topology into three areas, A, B and C, according to the boundary bus;

[0066] The boundary generatrix contained in region A is

[0067] BUS A =:{N 15 ,N 16 ,N 17 ,N 18 ,N 24}

[0068] BUS B =:{N 11 ,N 12 ,N 14 ,N 19 ,N 21 ,N 22}

[0069] BUS C =:{N3,N9,N 10}

[0070] In this embodiment, step S3 is specifically as follows:

[0071] S31: The area containing both the boundary bus and the public transmission line is regarded as the public area, and the rest of the area is regarded as the non-public area;

[0072] S32: The formula of the optimization framework is:

[0073]

[0074] stΦ(X CHANGE )=0,

[0075] Ω(X CHANGE )≤0,

[0076] Ψ(X0)=0,

[0077]

[0078] Among them, X CHANG represents the adjustable part in the mesh network topology, specifically the physical quantity in the adjustable device in the public area, the public transmission line set and the boundary bus set; X0 represents the non-adjustable part in the mesh network topology, specifically the physical quantity in the non-public area; φ(X CHANGE ) represents the optimization objective function of the public area, φ(X0) represents the optimization objective function of the non-public area, Φ(X CHANGE )=0 is the equality constraint of the common area; Ω(X CHANGE )≤0 is the inequality constraint of the public region; Ψ(X0)=0 is the equality constraint of the non-public region; is the inequality constraint for the non-public region;

[0079] In the specific implementation, minφ(X CHANGE )+φ(X0) together constitute the constraint function, which covers all conditions for power grid flow balance, safe operation, and operation of adjustable devices;

[0080] The optimization framework realizes the optimization and safe operation of the entire network system by exchanging information between regions through common transmission lines via boundary buses. For different problems arising in the power grid, it only needs to give a precise optimization objective function and concretize the constraints, and the power grid can be adjusted through the optimization framework to solve various problems arising in the power grid.

[0081] The present invention provides a partition-based meshed transmission and distribution network optimization system, comprising:

[0082] A common transmission line set acquisition module, used to acquire a mesh network topology diagram of the power grid, set the number of areas to be divided, and determine a common transmission line set in the mesh network topology diagram;

[0083] A region partitioning module, used to determine a boundary bus set in the mesh network topology map through the common transmission line set, and partition the mesh network topology map through the boundary bus set and the number of regions to obtain a plurality of regions;

[0084] An optimization framework building module, used for building an optimization framework through each of the regions, the common transmission line set and the boundary bus set;

[0085] The regulation module is used to regulate and optimize the power grid through the optimization framework.

[0086] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0087] The serial numbers of the embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. In a unit claim that lists several means, several of these means may be embodied by the same hardware item. The use of the words first, second, and third, etc. does not indicate any order and these words may be interpreted as identifiers.

[0088] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A partition-based meshed transmission and distribution network optimization method, characterized in that: include: S1: obtaining a mesh network topology diagram of the power grid, setting the number of regions to be divided, and determining a set of common transmission lines in the mesh network topology diagram; S2: determining a boundary bus set in the mesh network topology map by using the common transmission line set, and partitioning the mesh network topology map by using the boundary bus set and the number of regions to obtain a plurality of regions; S3: constructing an optimization framework through each of the regions, the common transmission line set and the boundary bus set; S4: Optimizing the power grid through the optimization framework; Step S2 is specifically as follows: S21: Acquire all buses in the mesh network topology diagram; S22: In the common transmission line set, the busbars at both ends of each common transmission line are taken as boundary busbars, and the set of all boundary busbars is taken as the boundary busbar set; S23: cutting the mesh network topology diagram along each boundary bus according to the number of regions to obtain multiple regions, each region requiring at least one power regulation unit; Step S3 is specifically as follows: S31: The area containing both the boundary bus and the public transmission line is regarded as the public area, and the rest of the area is regarded as the non-public area; S32: The formula of the optimization framework is: s.t.Φ(X CHANGE )=0, Oh(X CHANGE )≤0, Ψ(X0)=0, (X0)≤0. Among them, X CHANG represents the adjustable part in the mesh network topology, specifically the physical quantity in the adjustable device in the public area, the public transmission line set and the boundary bus set; X0 represents the non-adjustable part in the mesh network topology, specifically the physical quantity in the non-public area; φ(X CHANGE ) represents the optimization objective function of the common area, represents the optimization objective function of the non-public area, Φ(X CHANGE )=0 is the equality constraint of the common area; Ω(X CHANGE )≤0 is the inequality constraint of the public region; Ψ(X0)=0 is the equality constraint of the non-public region; (X0)≤0 is the inequality constraint of the non-public region.

2. The method for optimizing a meshed transmission and distribution network based on partitioning according to claim 1, characterized in that: Step S1 is specifically as follows: S11: setting the number of regions to be divided to k; S12: Acquire all transmission lines in the mesh network topology diagram; S13: Obtain the transmission capacity of each transmission line; S14: selecting the first 3k or 4k transmission lines with the largest transmission capacity as common transmission lines; S15: The set of all common transmission lines is taken as the common transmission line set.

3. A partition-based meshed transmission and distribution network optimization system, characterized in that: include: A common transmission line set acquisition module, used to acquire a mesh network topology diagram of the power grid, set the number of areas to be divided, and determine a common transmission line set in the mesh network topology diagram; A region partitioning module, used to determine a boundary bus set in the mesh network topology map through the common transmission line set, and partition the mesh network topology map through the boundary bus set and the number of regions to obtain a plurality of regions; An optimization framework building module, used for building an optimization framework through each of the regions, the common transmission line set and the boundary bus set; A regulation module, used for regulating and optimizing the power grid through the optimization framework; The specific workflow of the area division module is as follows: S21: Acquire all buses in the mesh network topology diagram; S22: In the common transmission line set, the busbars at both ends of each common transmission line are taken as boundary busbars, and the set of all boundary busbars is taken as the boundary busbar set; S23: cutting the mesh network topology diagram along each boundary bus according to the number of regions to obtain multiple regions, each region requiring at least one power regulation unit; The workflow of optimizing the framework building modules is as follows: S31: The area containing both the boundary bus and the public transmission line is regarded as the public area, and the rest of the area is regarded as the non-public area; S32: The formula of the optimization framework is: s.t.Φ(X CHANGE )=0, Oh(X CHANGE )≤0, Ψ(X0)=0, (X0)≤0. Among them, X CHANG represents the adjustable part in the mesh network topology, specifically the physical quantity in the adjustable device in the public area, the public transmission line set and the boundary bus set; X0 represents the non-adjustable part in the mesh network topology, specifically the physical quantity in the non-public area; φ(X CHANGE ) represents the optimization objective function of the common area, represents the optimization objective function of the non-public area, Φ(X CHANGE )=0 is the equality constraint of the common area; Ω(X CHANGE )≤0 is the inequality constraint of the public region; Ψ(X0)=0 is the equality constraint of the non-public region; (X0)≤0 is the inequality constraint of the non-public region.

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