Transmission difference weighted directed graph construction method and device of electric power system

Abstract

The invention discloses a transmission difference weighted directed graph construction method and device of a power system. The method comprises the following steps: acquiring system structure parameters of a power system, the system structure parameters comprising a generator inertia constant and a branch admittance matrix; according to the branch admittance matrix, obtaining the number of branches connected with each generator node of the power system and branch admittance between the nodes; distributing the inertia constants of the generators to the connected branches based on the admittance of the branches connected with the nodes of the generators, and obtaining system parameter data of the power system; based on the system parameter data, calculating a system transmission coefficient of the power system and constructing a system transmission coefficient matrix; performing normalization processing on the system transmission coefficient matrix to obtain a normalized transmission difference matrix; and constructing a transmission difference weighted directed graph of the power system according to the normalized transmission difference matrix.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and more specifically, to a method and device for constructing a transmission difference weighted directed graph of a power system. Background Art

[0002] At present, with the interconnection of regional power grids, large-scale development and utilization of new energy, and the goals of "carbon peak, carbon neutrality" and "building a power system dominated by new energy", on the one hand, the scale of the system is constantly expanding, and on the other hand, conventional synchronous power sources in the system are gradually being replaced by non-synchronous power sources such as wind and light, which reduces the system inertia level and increases the unevenness of inertia distribution. As a result, the spatial differences in the system's ability to resist disturbances increase, bringing challenges to the stable operation of the system. Therefore, how to accurately evaluate the spatial distribution of system inertia and its ability to resist disturbances has become a technical problem that needs to be solved urgently. Summary of the invention

[0003] In view of the deficiencies in the prior art, the present invention provides a method and device for constructing a transmission difference weighted directed graph of an electric power system.

[0004] According to one aspect of the present invention, a method for constructing a transmission difference weighted directed graph of a power system is provided, comprising:

[0005] Obtaining system structural parameters of the power system, wherein the system structural parameters include: generator inertia constant and branch admittance matrix;

[0006] According to the branch admittance matrix, the number of branches connected to each generator node of the power system and the branch admittance between nodes are obtained;

[0007] Based on the admittance of the branches connected to the generator nodes, the inertia constants of the generators are distributed to the connected branches to obtain the system parameter data of the power system;

[0008] Based on the system parameter data, the system transmission coefficient of the power system is calculated and the system transmission coefficient matrix is ​​constructed;

[0009] Normalizing the system transmission coefficient matrix to obtain a normalized transmission difference matrix;

[0010] According to the normalized transmission difference matrix, a transmission difference weighted directed graph of the power system is constructed.

[0011] Optionally, the distribution principle for distributing the generator inertia constant to the connected branches based on the admittance of the branches connected to the generator nodes is:

[0012]

[0013] Where M ij For the generator G i , Gj On line l ij The sum of the inertia constants acting on the line, that is, the total generator inertia constant allocated on the line is the sum of the generators allocated on both sides of the branch; B ij is the element in the i-th row and j-th column of the branch admittance B; M i is the inertia constant of the ith generator; M j is the inertia constant of the jth generator; n is the number of branches connected to each generator node.

[0014] Optionally, based on the system parameter data, a system transmission coefficient of the power system is calculated and a system transmission coefficient matrix is ​​constructed, including:

[0015] Based on the system parameter data, the inertia reference value and susceptance reference value of the power system are calculated, and the continuum branch inertia constant and susceptance per unit value are calculated according to the inertia reference value and susceptance reference value;

[0016] According to the inertia constant of the continuum branch and the per-unit value of susceptance, the system transmission coefficient is calculated and the system transmission coefficient matrix is ​​constructed.

[0017] Optionally, the continuum branch inertia constant k ij And the per unit value of susceptance h ij The calculation formula is:

[0018]

[0019] Where M ij For the generator G i , G j On line l ij The sum of the inertia constants acting on the 0 is the inertia reference value; B 0 B is the reference value of susceptance; ij is the element in the i-th row and j-th column of the branch admittance B.

[0020] Optionally, the system transmission coefficient T ij The calculation formula is:

[0021]

[0022] Where n is the number of connected branches of node j, k≠i means the number of branches participating in The calculated value is the branch connected to node j except branch l ij Other branches outside jk ;

[0023] The transmission coefficient set {T ij}, and construct the transmission coefficient matrix according to the node numbers i, j and the transmission direction between nodes: T = (T ij ) n×n .

[0024] Optionally, normalizing the system transmission coefficient matrix to obtain a normalized transmission difference matrix includes:

[0025] The comprehensive index of topological structure symmetry and parameter uniformity between system nodes is defined as the transmission difference coefficient ΔT, where

[0026] ΔT ij =T ij -T ji

[0027] Where, T ij For electromechanical wave node i through branch l ij Transmission coefficient when propagating to node j; T ji is the transmission coefficient of electromechanical waves when propagating in the reverse direction;

[0028] According to the transmission difference coefficient ΔT, the transmission difference coefficient matrix ΔT is constructed as:

[0029] ΔT=(ΔT ij ) n×n =TT'

[0030] In the formula, T=(T ij ) n×n is the system transmission coefficient matrix;

[0031] The transmission difference coefficient matrix ΔT is normalized to obtain the normalized transmission difference coefficient matrix ΔT N ,in,

[0032]

[0033] Where |ΔT| max is the maximum value of the transmission difference coefficient ΔT.

[0034] According to another aspect of the present invention, there is provided a device for constructing a transmission difference weighted directed graph of a power system, comprising:

[0035] A first acquisition module is used to acquire system structure parameters of the power system, wherein the system structure parameters include: generator inertia constant and branch admittance matrix;

[0036] The second acquisition module is used to obtain the number of branches connected to each generator node of the power system and the branch admittance between the nodes according to the branch admittance matrix;

[0037] A third acquisition module is used to distribute the generator inertia constant to the connected branches based on the admittance of the branches connected to the generator nodes, and acquire system parameter data of the power system;

[0038] A calculation module, used for calculating a system transmission coefficient of the power system and constructing a system transmission coefficient matrix based on system parameter data;

[0039] A fourth acquisition module is used to normalize the system transmission coefficient matrix to obtain a normalized transmission difference matrix;

[0040] A construction module is used to construct a transmission difference weighted directed graph of the power system according to the normalized transmission difference matrix.

[0041] According to another aspect of the present invention, a computer-readable storage medium is provided, wherein the storage medium stores a computer program, and the computer program is used to execute the method described in any one of the above aspects of the present invention.

[0042] According to another aspect of the present invention, an electronic device is provided, comprising: a processor; a memory for storing instructions executable by the processor; the processor is configured to read the executable instructions from the memory and execute the instructions to implement the method described in any one of the above aspects of the present invention.

[0043] Therefore, the inertia distribution evaluation index based on the electromechanical wave transmission coefficient proposed in the present invention can comprehensively reflect the relative strength relationship between the system's regional topological structure, the spatial distribution of inertia and the line susceptance, and evaluate the system's inertia spatial distribution degree and disturbance resistance capability, which is of great significance for optimizing the system's inertia distribution, improving the frequency dynamic response characteristics of the inertia weak links, and enhancing the system's stable operation capability. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0045] Figure 1 It is a flow chart of a method for constructing a transmission difference weighted directed graph of a power system provided by an exemplary embodiment of the present invention;

[0046] Figure 2 is a structural diagram of an 8×8 mesh system provided by an exemplary embodiment of the present invention;

[0047] Figure 3 is a transmission difference weighted directed graph of an 8×8 mesh system provided by an exemplary embodiment of the present invention;

[0048] Figure 4 is a diagram of system inertia variation provided by an exemplary embodiment of the present invention;

[0049] Figure 5 is a transmission difference weighted directed graph of a system inertia variation graph provided by an exemplary embodiment of the present invention;

[0050] Figure 6is a branch susceptance variation diagram provided by an exemplary embodiment of the present invention;

[0051] Figure 7 is a transmission difference weighted directed graph of a branch susceptance variation graph provided by an exemplary embodiment of the present invention;

[0052] Figure 8 It is a structural schematic diagram of a transmission difference weighted directed graph construction device for a power system provided by an exemplary embodiment of the present invention;

[0053] Fig. 9 This is a structure of an electronic device provided by an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0054] Below, the exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments of the present invention, and it should be understood that the present invention is not limited to the exemplary embodiments described here.

[0055] It should be noted that the relative arrangement of components and steps, the numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

[0056] Those skilled in the art can understand that the terms "first" and "second" in the embodiments of the present invention are only used to distinguish different steps, devices or modules, etc., and neither represent any specific technical meaning nor indicate the necessary logical order between them.

[0057] It should also be understood that, in the embodiments of the present invention, “plurality” may refer to two or more than two, and “at least one” may refer to one, two or more than two.

[0058] It should also be understood that any component, data or structure mentioned in the embodiments of the present invention can generally be understood as one or more, unless explicitly limited or otherwise indicated in the context.

[0059] In addition, the term "and / or" in the present invention is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present invention generally indicates that the associated objects before and after are in an "or" relationship.

[0060] It should also be understood that the description of the various embodiments of the present invention focuses on the differences between the various embodiments, and the same or similar aspects thereof can be referenced to each other, and for the sake of brevity, they will not be described one by one.

[0061] At the same time, it should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship.

[0062] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0063] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0064] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0065] Embodiments of the present invention can be applied to electronic devices such as terminal devices, computer systems, servers, etc., which can operate with many other general or special computing system environments or configurations. Examples of well-known terminal devices, computing systems, environments and / or configurations suitable for use with electronic devices such as terminal devices, computer systems, servers, etc. include, but are not limited to: personal computer systems, server computer systems, thin clients, thick clients, handheld or laptop devices, microprocessor-based systems, set-top boxes, programmable consumer electronics, network personal computers, small computer systems, large computer systems, and distributed cloud computing technology environments including any of the above systems, etc.

[0066] Electronic devices such as terminal devices, computer systems, servers, etc. can be described in the general context of computer system executable instructions (such as program modules) executed by computer systems. Generally, program modules can include routines, programs, object programs, components, logic, data structures, etc., which perform specific tasks or implement specific abstract data types. Computer systems / servers can be implemented in a distributed cloud computing environment, where tasks are performed by remote processing devices linked through a communication network. In a distributed cloud computing environment, program modules can be located on local or remote computing system storage media including storage devices.

[0067] Exemplary Methods

[0068] Figure 1 FIG. 1 is a flow chart of a method for constructing a transmission difference weighted directed graph of a power system provided by an exemplary embodiment of the present invention. This embodiment can be applied to electronic devices, such as Figure 1 As shown, the transmission difference weighted directed graph construction method 100 of the power system includes the following steps:

[0069] Step 101, obtaining system structure parameters of the power system, wherein the system structure parameters include: generator inertia constant and branch admittance matrix;

[0070] Step 102, obtaining the number of branches connected to each generator node of the power system and the branch admittance between nodes according to the branch admittance matrix;

[0071] Step 103, allocating the generator inertia constant to the connected branches based on the admittance of the branches connected to the generator nodes, and acquiring system parameter data of the power system;

[0072] Step 104, based on the system parameter data, calculating the system transmission coefficient of the power system and constructing a system transmission coefficient matrix;

[0073] Step 105, normalizing the system transmission coefficient matrix to obtain a normalized transmission difference matrix;

[0074] Step 106: construct a transmission difference weighted directed graph of the power system according to the normalized transmission difference matrix.

[0075] Specifically, the total inertia index of the system from the perspective of the center of inertia (COI) of the traditional synchronous machine system cannot accurately measure the differences in the spatiotemporal distribution of inertia and the spatiotemporal dynamic differences in frequency in large-scale power systems. The present invention proposes an inertia distribution evaluation index and calculation method based on the electromechanical wave transmission coefficient. First, the relationship function between the transmission coefficient and the system topology, inertia distribution and line admittance is constructed based on the electromechanical wave theory; secondly, the discrete model of the power system is processed continuously to establish a transmission difference coefficient index and a transmission difference coefficient matrix that reflect the degree of connection and difference between the generator nodes, and describe the spatial distribution level of inertia of the system; finally, the transmission difference coefficient index is visualized with the help of a weighted directed graph, so as to understand the spatial distribution information of the system inertia contained in the matrix. The method comprises the following steps:

[0076] (1) Obtain system structure parameters:

[0077] This method is an offline calculation method. First, the system structure parameters need to be obtained, including the system branch admittance B, the generator inertia constant M, and the branch admittance matrix Y;

[0078] (2) Continuous processing of system model:

[0079] The continuous processing of the power system mainly involves the continuous processing of the generator inertia constant.

[0080] First, based on the admittance matrix Y, the number of connected branches n of each generator node and the inter-node branch admittance B are obtained;

[0081] Secondly, the generator inertia constant is distributed to its connected branches based on the susceptance of the branches connected to the generator node. The specific distribution principle is as follows:

[0082]

[0083] Where M ij For the generator G i , G j On line l ij The sum of the inertia constants acting on the line, that is, the total generator inertia constant allocated on the line is the sum of the generators allocated on both sides of the branch.

[0084] (3) Determine the system parameter calculation benchmark value and per unit value:

[0085] Determine the system inertia and susceptance reference values ​​M according to the specific system parameters and calculation requirements. 0 , B 0 , calculate the inertia constant and per-unit susceptance value k of the continuum branch according to the following formula: ij 、h ij ;

[0086]

[0087] (4) Calculate the per-unit wave impedance of each branch under the continuum model

[0088]

[0089] In the formula, Z c0 is the branch wave impedance reference value calculated based on the parameter reference value, is the per-unit value of the branch wave impedance.

[0090] (5) Calculate the system transmission coefficient and construct the system transmission coefficient matrix T:

[0091] Calculate the branch l in sequence ij When it is the incident wave branch, the transmission coefficient when the disturbance propagates from node i to node j is T ij , the calculation formula is:

[0092]

[0093] Where n is the number of connected branches of node j, k≠i means the number of branches participating in The calculated value is the branch connected to node j except branch l ij Other branches outside jk .

[0094] The transmission coefficient set {T ij}, and construct the following transmission coefficient matrix based on the node numbers i, j and the transmission direction between nodes:

[0095] T=(T ij ) n×n (6)

[0096] (6) Normalized transmission difference matrix ΔT N :

[0097] The transmission difference coefficient ΔT is defined as a comprehensive indicator reflecting the symmetry of the topological structure and the uniformity of parameters between system nodes:

[0098] ΔT ij =T ij -T ji (7)

[0099] Where, T ij For electromechanical wave node i through branch l ij Transmission coefficient when propagating to node j, similarly T ji is the transmission coefficient of the electromechanical wave when propagating in the reverse direction.

[0100] The transmission difference coefficient matrix ΔT is constructed as:

[0101] ΔT=(ΔT ij ) n×n =TT' (8)

[0102] Where T=(T ij ) n×n is the system transmission coefficient matrix.

[0103] The matrix ΔT is normalized as follows to obtain the normalized transmission difference coefficient matrix:

[0104]

[0105] (7) Construction of transmission difference weighted directed graph:

[0106] Construct the normalized transmission difference matrix ΔT N The corresponding weighted directed graph G = (V, E), where V is the vertex set of the graph G, corresponding to the set of system generators, that is, corresponding to the normalized transmission difference matrix ΔT N Row (or column) number; E is the directed edge set of graph G, corresponding to the transmission difference set between generator nodes in the system, that is, the normalized transmission difference matrix ΔT N elements.

[0107] Based on the definition of the weighted directed graph G above, we can know that the adjacency matrix A(E) of the weighted directed graph G is

[0108] A(E) = ΔT N (10)

[0109] Based on the adjacency matrix A(E), the drawing of the weighted directed graph G can be realized through computer programming.

[0110] In one embodiment of the present application, an ideal 8×8 grid system is taken as an example to illustrate the evaluation effect of an inertia distribution evaluation index based on the electromechanical wave transmission coefficient. In the ideal grid system, each node is connected to a generator, and the inertia, line length, and unit length susceptance of each generator are equal. The line resistance and parallel capacitance are ignored. The system topology is as follows: Figure 2 The system structure parameters are shown in Table 1.

[0111] Table 1 System structure parameters

[0112]

[0113] (1) Obtain system structure parameters:

[0114] Obtain the system structural parameters of the example described in this article, including the system branch admittance B = 5pu, the generator inertia constant H = [5 5…5] 1×64 And the branch admittance matrix

[0115]

[0116] (2) Continuous processing of system model:

[0117] a. Calculate the number of branches connected to each generator node n = [2 3 3…2] 1×64 ;

[0118] b. The generator inertia is distributed to the branch, with branch l 2,10 For example:

[0119]

[0120] Similarly, the inertia allocated to other branches can be calculated:

[0121]

[0122] (3) Determine the system parameter calculation benchmark value and per unit value:

[0123] Take the reference value M 0 =5s, B 0 =5pu. Then the inertia constant of the continuum branch and the per-unit value of susceptance k can be calculated. ij 、h ij :

[0124]

[0125] (4) Calculate the per-unit wave impedance of each branch

[0126]

[0127] In the formula, Does not exist to indicate branch l ij .

[0128] (5) Calculate the transmission coefficient and construct the system transmission coefficient matrix T:

[0129] Branch l 2,10 Taking the incident wave branch as an example, calculate the transmission coefficient T when the disturbance propagates from node 2 to node 10 2,10 :

[0130]

[0131] Similarly, the transmission coefficients are calculated in turn and the transmission coefficient matrix T is constructed

[0132]

[0133] (6) Normalized transmission difference matrix ΔT N :

[0134]

[0135] Where T=(T ij ) n×n is the system transmission coefficient matrix.

[0136] The matrix ΔT is normalized as follows to obtain the normalized transmission difference coefficient matrix matrix

[0137]

[0138] (7) Construction of transmission difference weighted directed graph

[0139] Let the adjacency matrix A(E) of the weighted directed graph G be

[0140]

[0141] Based on the adjacency matrix A(E), the weighted directed graph G is drawn by computer programming. The drawn transmission difference weighted directed graph G is as follows: Figure 3 shown.

[0142] When the system structural parameters change, this calculation method can still calculate its corresponding transmission difference coefficient matrix and construct its transmission difference weighted directed graph G. Figure 4 and Figure 5 The topological structure diagram after adding the nine-node inertia (28-30, 36-38, 44-46) and its corresponding transmission difference weighted directed graph G; Figure 6 and Figure 7The topological structure diagram after increasing the branch susceptance in the middle area and its corresponding transmission difference weighted directed graph G.

[0143] (8) Analysis of the evaluation effect of transmission difference coefficient matrix and transmission difference weighted directed graph inertia distribution

[0144] 1. When the system inertia is evenly distributed:

[0145] The transmission difference weighted directed graph G is as follows Figure 3 As shown, the nodes in the figure correspond to the system generator nodes; the directions of the directed line segments between the nodes correspond to the positive inter-node directions corresponding to the transmission difference coefficients in the transmission difference matrix, and the weights of the directed branches are the modulus values ​​of the transmission difference coefficients.

[0146] There are no directed branches between some nodes in the figure, indicating that the transmission coefficients between these generator nodes and their adjacent generator nodes in the system are equal, that is, the system topology and parameters are symmetrical and uniform; there are weighted directed branches between some nodes in the figure, indicating that for the two generator nodes on both sides of the same branch, the transmission coefficient is larger when the electromechanical disturbance propagates along the directed branch direction, and the edge weights in the figure reflect the degree of difference in the transmission coefficient. Taking nodes 4 and 12 in the figure as an example, the direction of the directed branch between nodes is from node 12 to 4, indicating that the transmission coefficient is larger when the disturbance propagates along this direction; the weights of the directed branches between nodes 4 and 12 and between nodes 12 and 20 are 0.10787 and 0.0098188 respectively, indicating that the transmission difference is smaller when the disturbance propagates between nodes 12 and 20, and the system topology and parameters are more uniform compared to nodes 4 and 12.

[0147] 2. When the system inertia distribution changes:

[0148] The transmission difference weighted directed graph G is as follows Figure 5 shown.

[0149] When the system inertia distribution changes, the corresponding weighted directed graph changes accordingly. Figure 5 It can be seen that the transmission difference coefficient index inside the nine-node area (28-30, 36-38, 44-46) with increased inertia is relatively small, 0.0898-0.0989, and the transmission difference coefficient between the connected areas is as high as 0.67-0.79, forming an obvious high-value boundary, reflecting the difference boundary of the system inertia distribution. B. The directions of the directed branches representing the transmission difference coefficient at the high-value boundary are all from the nine-node area with increased inertia to the connected external area, indicating that the transmission coefficient is larger when the electromechanical disturbance propagates from the nine-node area with increased inertia to the external area, and the electromechanical disturbance in the central area is easier to propagate outward.

[0150] 3. When the system line susceptance distribution changes:

[0151] The transmission difference weighted directed graph G is as follows Figure 7 shown.

[0152] When the system branch susceptance changes, the directed graph changes accordingly. Figure 7 It can be seen that the transmission difference coefficient index within the region composed of the middle 16 nodes is relatively small, ranging from 0.007 to 0.196 (some 0.498), and the transmission difference coefficient between the connected regions is as high as 0.67 to 0.81, forming an obvious high-value boundary, reflecting the difference boundary of the system branch susceptance and the difference boundary of the inertia distribution density caused by the electrical distance under the same node inertia. B. The directions of the directed branches representing the transmission difference coefficient at the high-value boundary are all from the middle region to the connected external region, indicating that the transmission coefficient is larger when the electromechanical disturbance propagates from the middle region to the external region, and the electromechanical disturbance in the central region is easier to propagate outward.

[0153] Therefore, the inertia distribution evaluation index based on the electromechanical wave transmission coefficient proposed in the present invention can comprehensively reflect the relative strength relationship between the system's regional topological structure, the spatial distribution of inertia and the line susceptance, and evaluate the system's inertia spatial distribution degree and disturbance resistance capability, which is of great significance for optimizing the system's inertia distribution, improving the frequency dynamic response characteristics of the inertia weak links, and enhancing the system's stable operation capability.

[0154] Exemplary Devices

[0155] Figure 8 FIG. 1 is a schematic diagram of a structure of a transmission difference weighted directed graph construction device for a power system provided by an exemplary embodiment of the present invention. Figure 8 As shown, the device 800 includes:

[0156] A first acquisition module 810 is used to acquire system structure parameters of the power system, wherein the system structure parameters include: generator inertia constant and branch admittance matrix;

[0157] The second acquisition module 820 is used to acquire the number of branches connected to each generator node of the power system and the branch admittance between the nodes according to the branch admittance matrix;

[0158] A third acquisition module 830 is used to allocate the generator inertia constant to the connected branches based on the admittance of the branches connected to the generator nodes, and acquire system parameter data of the power system;

[0159] A calculation module 840, for calculating a system transmission coefficient of the power system and constructing a system transmission coefficient matrix based on the system parameter data;

[0160] A fourth acquisition module 850 is used to normalize the system transmission coefficient matrix to obtain a normalized transmission difference matrix;

[0161] The construction module 860 is used to construct a transmission difference weighted directed graph of the power system according to the normalized transmission difference matrix.

[0162] Optionally, the distribution principle for distributing the generator inertia constant to the connected branches based on the admittance of the branches connected to the generator nodes is:

[0163]

[0164] Where M ij For the generator G i , G j On line l ij The sum of the inertia constants acting on the line, that is, the total generator inertia constant allocated on the line is the sum of the generators allocated on both sides of the branch; B ij is the element in the i-th row and j-th column of the branch admittance B; M i is the inertia constant of the ith generator; M j is the inertia constant of the jth generator; n is the number of branches connected to each generator node.

[0165] Optionally, the calculation module 840 includes:

[0166] The first calculation submodule is used to calculate the inertia reference value and the susceptance reference value of the power system based on the system parameter data, and calculate the continuum branch inertia constant and the susceptance per unit value according to the inertia reference value and the susceptance reference value;

[0167] The second calculation submodule is used to calculate the system transmission coefficient and construct the system transmission coefficient matrix according to the inertia constant of the continuum branch and the per-unit value of the susceptance.

[0168] Optionally, the continuum branch inertia constant k ij And the per unit value of susceptance h ij The calculation formula is:

[0169]

[0170] Where M ij For the generator G i , G j On line l ij The sum of the inertia constants acting on the 0 is the inertia reference value; B 0 B is the reference value of susceptance; ij is the element in the i-th row and j-th column of the branch admittance B.

[0171] Optionally, the system transmission coefficient T ij The calculation formula is:

[0172]

[0173] Where n is the number of connected branches of node j, k≠i means participating The calculated value is the branch connected to node j except branch l ij Other branches outside jk ;

[0174] The transmission coefficient set {T ij}, and construct the transmission coefficient matrix according to the node numbers i, j and the transmission direction between nodes: T = (T ij ) n×n .

[0175] Optionally, the fourth acquisition module 850 includes:

[0176] A submodule is defined to define the comprehensive index of topological structure symmetry and parameter uniformity between system nodes as the transmission difference coefficient ΔT, where

[0177] ΔT ij =T ij -T ji

[0178] Where, T ij For electromechanical wave node i through branch l ij Transmission coefficient when propagating to node j; T ji is the transmission coefficient of electromechanical waves when propagating in the reverse direction;

[0179] The construction submodule is used to construct the transmission difference coefficient matrix ΔT according to the transmission difference coefficient ΔT:

[0180] ΔT=(ΔT ij ) n×n =TT'

[0181] In the formula, T=(T ij ) n×n is the system transmission coefficient matrix;

[0182] The processing submodule is used to normalize the transmission difference coefficient matrix ΔT to obtain the normalized transmission difference coefficient matrix ΔT N ,in,

[0183]

[0184] Where |ΔT| max is the maximum value of the transmission difference coefficient ΔT.

[0185] Exemplary Electronic Devices

[0186] Fig. 9 This is a structure of an electronic device provided by an exemplary embodiment of the present invention. Fig. 9As shown, the electronic device 90 includes one or more processors 91 and a memory 92 .

[0187] The processor 91 may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions.

[0188] The memory 92 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory (cache), etc. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 91 may run the program instructions to implement the methods of the software programs of the various embodiments of the present invention described above and / or other desired functions. In one example, the electronic device may also include: an input device 93 and an output device 94, which are interconnected via a bus system and / or other forms of connection mechanisms (not shown).

[0189] In addition, the input device 93 may also include, for example, a keyboard, a mouse, and the like.

[0190] The output device 94 can output various information to the outside, and can include, for example, a display, a speaker, a printer, a communication network and a remote output device connected thereto.

[0191] Of course, to simplify, Fig. 9 Only some of the components related to the present invention in the electronic device are shown, and components such as a bus, an input / output interface, etc. are omitted. In addition, the electronic device may further include any other appropriate components according to specific application conditions.

[0192] Exemplary computer program products and computer-readable storage media

[0193] In addition to the above-mentioned methods and devices, an embodiment of the present invention may also be a computer program product, which includes computer program instructions, which, when executed by a processor, enable the processor to execute the steps of the method according to various embodiments of the present invention described in the above-mentioned "Exemplary Method" section of this specification.

[0194] The computer program product may be written in any combination of one or more programming languages ​​to write program code for performing the operations of the embodiments of the present invention, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0195] In addition, an embodiment of the present invention may also be a computer-readable storage medium having computer program instructions stored thereon, which, when executed by a processor, enable the processor to execute the steps of the method according to various embodiments of the present invention described in the above “Exemplary Method” section of this specification.

[0196] The computer readable storage medium can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can include, for example, but is not limited to, a system, system or device of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination of the above. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0197] The basic principle of the present invention is described above in conjunction with specific embodiments. However, it should be pointed out that the advantages, strengths, effects, etc. mentioned in the present invention are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. must be possessed by each embodiment of the present invention. In addition, the specific details disclosed above are only for the purpose of illustration and facilitation of understanding, rather than limitation, and the above details do not limit the present invention to being implemented by adopting the above specific details.

[0198] Each embodiment in this specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the system embodiment, since it basically corresponds to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0199] The block diagrams of the devices, systems, equipment, and systems involved in the present invention are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagram. As will be appreciated by those skilled in the art, these devices, systems, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The word "such as" used here refers to the phrase "such as but not limited to", and can be used interchangeably with it.

[0200] The method and system of the present invention may be implemented in many ways. For example, the method and system of the present invention may be implemented by software, hardware, firmware or any combination of software, hardware, firmware. The above order of steps for the method is only for illustration, and the steps of the method of the present invention are not limited to the order specifically described above, unless otherwise specifically stated. In addition, in some embodiments, the present invention may also be implemented as a program recorded in a recording medium, which includes machine-readable instructions for implementing the method according to the present invention. Thus, the present invention also covers a recording medium storing a program for executing the method according to the present invention.

[0201] It should also be noted that in the system, device and method of the present invention, each component or each step can be decomposed and / or recombined. These decompositions and / or recombinations should be regarded as equivalent schemes of the present invention. The above description of the disclosed aspects is provided to enable any technician in the field to make or use the present invention. Various modifications to these aspects are very obvious to those skilled in the art, and the general principles defined here can be applied to other aspects without departing from the scope of the present invention. Therefore, the present invention is not intended to be limited to the aspects shown here, but in accordance with the widest range consistent with the principles and novel features disclosed here.

[0202] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present invention to the forms disclosed herein. Although a number of example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A method for constructing a transmission difference weighted directed graph of a power system, characterized in that: include: Acquiring system structural parameters of the power system, wherein the system structural parameters include: generator inertia constant and branch admittance matrix; According to the branch admittance matrix, the number of branches connected to each generator node of the power system and the branch admittance between nodes are obtained; Based on the admittance of the branch connected to the generator node, the generator inertia constant is distributed to the connected branch to obtain system parameter data of the power system; Based on the system parameter data, calculating the system transmission coefficient of the power system and constructing a system transmission coefficient matrix; Normalizing the system transmission coefficient matrix to obtain a normalized transmission difference matrix; A transmission difference weighted directed graph of the power system is constructed according to the normalized transmission difference matrix.

2. The method according to claim 1, characterized in that The distribution principle for distributing the generator inertia constant to the connected branches based on the admittance of the branches connected to the generator nodes is: Where M ij For the generator G i , G j On line l ij The sum of the inertia constants acting on the line, that is, the total generator inertia constant allocated on the line is the sum of the generators allocated on both sides of the branch; B ij is the element in the i-th row and j-th column of the branch admittance B; M i is the inertia constant of the ith generator; M j is the inertia constant of the jth generator; n is the number of branches connected to each generator node.

3. The method according to claim 1, characterized in that Based on the system parameter data, calculating the system transmission coefficient of the power system and constructing a system transmission coefficient matrix, including: Based on the system parameter data, calculating the inertia reference value and the susceptance reference value of the power system, and calculating the continuum branch inertia constant and the susceptance per unit value according to the inertia reference value and the susceptance reference value; According to the inertia constant of the continuum branch and the per-unit value of susceptance, the system transmission coefficient is calculated and the system transmission coefficient matrix is ​​constructed.

4. The method according to claim 3, characterized in that The inertia constant k of the continuum branch ij and the per-unit value of the susceptance h ij The calculation formula is: Where M ij For the generator G i , G j On line l ij The sum of the inertia constants acting on the upper surface; M0 is the inertia reference value; B0 is the susceptance reference value; B ij is the element in the i-th row and j-th column of the branch admittance B.

5. The method according to claim 4, characterized in that The system transmission coefficient T ij The calculation formula is: Where n is the number of connected branches of node j, k≠i means the number of branches participating in The calculated value is the branch connected to node j except branch l ij Other branches outside jk ; The transmission coefficient set {T ij }, the transmission coefficient matrix is ​​constructed according to the node numbers i, j and the transmission direction between nodes: T = (T ij ) n×n .

6. The method according to claim 1, characterized in that Normalizing the system transmission coefficient matrix to obtain a normalized transmission difference matrix includes: The comprehensive index of topological structure symmetry and parameter uniformity between system nodes is defined as the transmission difference coefficient ΔT, where ΔT ij =T ij -T ji Where, T ij For electromechanical wave node i through branch l ij Transmission coefficient when propagating to node j; T ji is the transmission coefficient of electromechanical waves when propagating in the reverse direction; According to the transmission difference coefficient ΔT, the transmission difference coefficient matrix ΔT is constructed as: ΔT=(ΔT ij ) n×n =T-T' In the formula, T=(T ij ) n×n is the system transmission coefficient matrix; The transmission difference coefficient matrix ΔT is normalized to obtain a normalized transmission difference coefficient matrix ΔT N ,in, Where |ΔT| max is the maximum value of the transmission difference coefficient ΔT.

7. A transmission difference weighted directed graph construction device for a power system, characterized in that: include: A first acquisition module is used to acquire system structure parameters of the power system, wherein the system structure parameters include: generator inertia constant and branch admittance matrix; A second acquisition module is used to acquire the number of branches connected to each generator node of the power system and the branch admittance between nodes according to the branch admittance matrix; A third acquisition module is used to distribute the generator inertia constant to the connected branches based on the admittance of the branches connected to the generator nodes, and acquire system parameter data of the power system; A calculation module, used for calculating the system transmission coefficient of the power system and constructing a system transmission coefficient matrix based on the system parameter data; A fourth acquisition module is used to normalize the system transmission coefficient matrix to obtain a normalized transmission difference matrix; A construction module is used to construct a transmission difference weighted directed graph of the power system according to the normalized transmission difference matrix.

8. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, and the computer program is used to execute the method according to any one of claims 1 to 6.

9. An electronic device, characterized in that: The electronic device comprises: processor; a memory for storing instructions executable by the processor; The processor is used to read the executable instructions from the memory and execute the instructions to implement the method described in any one of claims 1 to 6.

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