Method and device for correcting static security domain coefficient of electric power system in N-1 fault scene

Abstract

The invention discloses an N-1 fault scene electric power system static safety domain coefficient correction method and device, and the method comprises the steps: carrying out the calculation according to the network parameters of an electric power system, and obtaining a static safety domain coefficient of the electric power system in a fault-free scene; using a static security domain coefficient of the power system in a fault-free scene to represent a power flow transfer degree caused by a set N-1 fault; calculating to obtain the correction of the static security domain coefficient of the power system in the fault-free scene by the power flow transfer caused by the set N-1 fault; and according to the obtained correction amount of the static security domain coefficient of the power system in the fault-free scene, calculating to obtain the static security domain coefficient of the power system in the set N-1 fault scene. Based on the static security domain coefficient in the fault-free scene, the correction method of the security domain coefficient in the fault scene is provided, and the rapid generation of the static security domain coefficient of the electric power system in the N-1 fault scene is realized.

Description

Technical Field

[0001] The present invention relates to the field of power system safety technology, and in particular to a method and device for correcting a static safety domain coefficient of a power system under N-1 fault scenarios. Background Art

[0002] In the field of power system safety, traditional static safety analysis and calculation are based on the point-by-point method, that is, the power flow calculation must be re-performed for each different system operation mode. The safety domain is a method of analyzing the safety of the power system from the perspective of the domain. The static safety domain defined in the power injection space of the power system node is a set of operating points that meet the thermal stability constraints of the power system, and for a specified power system network topology, its safety domain in the node injection power space is uniquely determined. The thermal stability safety constraint mainly considers whether the system exceeds its thermal stability limit in normal operation or in the expected accident state. The overload index of the transmission line is expressed by the maximum current carrying capacity of the line.

[0003] At present, the existing technology can solve the safety domain coefficient under a specific network topology based on the DC power flow equation. However, for the actual power grid, the online application of the safety domain requires that the safety domain coefficient can be solved and stored offline. At present, it is difficult to store and call the safety domain coefficient of high-dimensional and multi-fault scenarios.

[0004] Therefore, how to quickly obtain the static safety domain coefficient of the power system for the N-1 fault scenario has become an urgent problem to be solved. Summary of the invention

[0005] To this end, the present invention provides a method and device for correcting the static safety domain coefficient of an electric power system in an N-1 fault scenario. The method is based on the static safety domain coefficient in a fault-free scenario, proposes a method for correcting the safety domain coefficient in a fault scenario, and realizes the rapid generation of the static safety domain coefficient of the electric power system in the N-1 fault scenario.

[0006] In order to achieve the above object, the present invention provides the following technical solution: a method for correcting the static safety region coefficient of an electric power system in an N-1 fault scenario, comprising:

[0007] According to the network parameters of the power system, the static safety domain coefficient of the power system in a fault-free scenario is calculated;

[0008] Using the static safety domain coefficient of the power system in a no-fault scenario, the degree of power flow transfer caused by the set N-1 fault is expressed; and obtaining by calculation a correction amount of the power flow transfer caused by the set N-1 fault to the static safety domain coefficient of the power system in a no-fault scenario;

[0009] According to the obtained correction amount of the static safety region coefficient of the power system in the no-fault scenario, the static safety region coefficient of the power system in the set N-1 fault scenario is calculated.

[0010] As a preferred solution for the correction method of the static safety domain coefficient of the power system in an N-1 fault scenario, the expression of the static safety domain coefficient of the power system in a fault-free scenario is:

[0011]

[0012] Where P i is the active power output of system node i; P i min and P i max are the lower and upper limits of active output of system node i respectively; is the safety region coefficient of the power injection into node i by the power flow constraint of branch l; L is the set of branches, L = {1, 2, ..., M}; is the maximum active power value that branch l can bear; B is the set of nodes outside the balancing node, B = {1, 2, ..., N}.

[0013] As a preferred solution of a method for correcting the static safety domain coefficient of an electric power system in an N-1 fault scenario, in the process of using the static safety domain coefficient of the electric power system in a fault-free scenario to express the degree of power flow transfer caused by setting the N-1 fault, the static safety domain coefficient of the electric power system in a fault-free scenario is used to express the disconnection power flow transfer distribution factor of branch k to branch l; the expression of the disconnection power flow transfer distribution factor of branch k to branch l is:

[0014]

[0015] Where PTDF m,n,l is the power transfer distribution factor of the node pair (m, n) on branch l expressed by the safety region boundary coefficient; PTDF m,n,k is the power transfer distribution factor of the node pair (m, n) on branch k expressed by the safety region boundary coefficient; The safety region coefficient of the power injected into node m by the power flow constraint of branch l; The safety region coefficient of the power injected into node n by the power flow constraint of branch l; The safety region coefficient of the power injected into node m by the power flow constraint of branch k; is the safety region coefficient of the power injected into node n by the power flow constraint of branch k.

[0016] As a preferred solution of the method for correcting the static safety domain coefficient of the power system in an N-1 fault scenario, in the process of obtaining the correction amount of the static safety domain coefficient of the power system in a fault-free scenario caused by the power flow transfer caused by the set N-1 fault by calculation, the correction amount is expressed by the relationship between the power flow of branch l and the injected power of node i under the set N-1 fault; the relationship between the power flow of branch l and the injected power of node i is expressed as follows:

[0017]

[0018] Where P l br is the flow of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch k.

[0019] As a preferred solution of a method for correcting a static safety domain coefficient of a power system in an N-1 fault scenario, the static safety domain coefficient expression of the power system in the set N-1 fault scenario is:

[0020]

[0021] In the formula, It is the static safety domain coefficient of the power system under the set N-1 fault scenario.

[0022] The present invention also provides a device for correcting static safety domain coefficients of an electric power system in an N-1 fault scenario, based on the above method for correcting static safety domain coefficients of an electric power system in an N-1 fault scenario, comprising:

[0023] A fault-free static safety domain coefficient acquisition module is used to calculate and obtain the static safety domain coefficient of the power system in a fault-free scenario according to the network parameters of the power system;

[0024] A module for obtaining a correction amount of a non-fault static safety domain coefficient is used to use the static safety domain coefficient of the power system in a non-fault scenario to indicate the degree of power flow transfer caused by a set N-1 fault; and to obtain a correction amount of the static safety domain coefficient of the power system in a non-fault scenario caused by the power flow transfer caused by the set N-1 fault by calculation;

[0025] The N-1 fault static safety domain coefficient acquisition module is used to calculate the static safety domain coefficient of the power system under the set N-1 fault scenario based on the correction amount of the static safety domain coefficient of the power system under the fault-free scenario.

[0026] As a preferred solution of a static safety domain coefficient correction device for an N-1 fault scenario power system, in the fault-free static safety domain coefficient acquisition module, the expression of the static safety domain coefficient of the power system in a fault-free scenario is:

[0027]

[0028] Where P i is the active power output of system node i; P i min and P i max分 are the lower and upper limits of active output of system node i; is the safety region coefficient of the power injection into node i by the power flow constraint of branch l; L is the set of branches, L = {1, 2, ..., M}; is the maximum active power value that branch l can bear; B is the set of nodes outside the balancing node, B = {1, 2, ..., N}.

[0029] As a preferred solution of a static safety domain coefficient correction device for an N-1 fault scenario power system, in the fault-free static safety domain coefficient correction amount acquisition module, in the process of using the static safety domain coefficient of the power system in a fault-free scenario to represent the degree of power flow transfer caused by setting the N-1 fault, the static safety domain coefficient of the power system in a fault-free scenario represents the disconnection power flow transfer distribution factor of branch k to branch l; the expression of the disconnection power flow transfer distribution factor of branch k to branch l is:

[0030]

[0031] Where PTDF m,n,l is the power transfer distribution factor of the node pair (m, n) on branch l expressed by the safety region boundary coefficient; PTDF m,n,k is the power transfer distribution factor of the node pair (m, n) on branch k expressed by the safety region boundary coefficient; The safety region coefficient of the power injected into node m by the power flow constraint of branch l; The safety region coefficient of the power injected into node n by the power flow constraint of branch l; The safety region coefficient of the power injected into node m by the power flow constraint of branch k; is the safety region coefficient of the power injected into node n by the power flow constraint of branch k.

[0032] As a preferred solution of a static safety domain coefficient correction device for an N-1 fault scenario power system, in the fault-free static safety domain coefficient correction amount acquisition module, in the process of obtaining the correction amount of the static safety domain coefficient of the power system in a fault-free scenario by calculating the power flow transfer caused by the set N-1 fault, the correction amount is expressed by the relationship between the power flow of branch l and the injected power of node i under the set N-1 fault; the relationship between the power flow of branch l and the injected power of node i is expressed as follows:

[0033]

[0034] Where P l br is the flow of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch k.

[0035] As a preferred solution of a static safety domain coefficient correction device for an N-1 fault scenario power system, in the N-1 fault static safety domain coefficient acquisition module, the static safety domain coefficient expression of the power system under the set N-1 fault scenario is:

[0036]

[0037] In the formula, It is the static safety domain coefficient of the power system under the set N-1 fault scenario.

[0038] The present invention has the following advantages: according to the network parameters of the power system, the static safety domain coefficient of the power system in a fault-free scenario is calculated; the static safety domain coefficient of the power system in a fault-free scenario is used to indicate the degree of power flow transfer caused by the set N-1 fault; the correction amount of the power flow transfer caused by the set N-1 fault to the static safety domain coefficient of the power system in a fault-free scenario is obtained by calculation; according to the correction amount of the static safety domain coefficient of the power system in a fault-free scenario, the static safety domain coefficient of the power system in the set N-1 fault scenario is calculated. Based on the static safety domain coefficient in a fault-free scenario, the present invention proposes a correction method for the safety domain coefficient in a fault scenario, and realizes the rapid generation of the static safety domain coefficient of the power system in the N-1 fault scenario. Based on the parameters of the safety domain constraint equation obtained in the fault-free base state, the power flow transfer factor is determined by the safety domain coefficient. Based on the safety domain coefficient obtained in the base state, the safety domain coefficient of the system under the corresponding N-1 fault is calculated under different line states, and the thermal stability safety domain constraint is obtained, so as to realize the rapid calculation of the thermal stability safety domain under the N-1 fault. The safety domain coefficients and constraints obtained under different faults can also be used as a reference for N-1 fault scanning to obtain the vulnerable links of the system, providing an effective reference for further determining the safety and stability of the system and avoiding cascading failures. The present invention starts from the rapid generation of the static safety domain coefficient of the power system in the N-1 fault scenario, and looks for the vulnerable links of the power system to ensure the safe and reliable operation of the power system; the present invention uses the safety domain coefficient of the fault-free scenario to generate the static safety domain coefficient of the power system in the N-1 fault scenario. It only needs to store a set of original data to generate the static safety domain coefficients of all required fault scenarios, which can effectively avoid the storage and call problems of the safety domain coefficients of high-dimensional and multi-fault scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0040] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantial technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0041] Figure 1A schematic flow chart of a method for correcting a static safety domain coefficient of an electric power system in an N-1 fault scenario provided in Embodiment 1 of the present invention;

[0042] Figure 2 A schematic diagram of an IEEE 24-node system and a schematic diagram of a fault location in a possible embodiment provided in Embodiment 1 of the present invention;

[0043] Figure 3 This is a schematic diagram of the architecture of a static safety domain coefficient correction device for an N-1 fault scenario power system provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0044] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. 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.

[0045] Example 1

[0046] See also Figure 1 Embodiment 1 of the present invention provides a method for correcting a static safety domain coefficient of an electric power system in an N-1 fault scenario, comprising the following steps:

[0047] S1. According to the network parameters of the power system, the static safety domain coefficient of the power system in a fault-free scenario is calculated;

[0048] S2. Using the static safety domain coefficient of the power system in a no-fault scenario, the degree of power flow transfer caused by the set N-1 fault is expressed; and the correction amount of the power flow transfer caused by the set N-1 fault to the static safety domain coefficient of the power system in a no-fault scenario is obtained by calculation;

[0049] S3. According to the obtained correction amount of the static safety region coefficient of the power system in the no-fault scenario, the static safety region coefficient of the power system in the set N-1 fault scenario is calculated.

[0050] In this embodiment, in step S1, a static safety domain coefficient of the power system in a no-fault scenario is calculated based on the network parameters of the power system;

[0051] Specifically, for a given power system, it is assumed that it contains N+1 nodes and M branches. The nodes are numbered from 0 to N, node 0 is a balance node, and the set of nodes other than the balance node is B = {1, 2, ..., N}; the branches are numbered from 1 to M, and the set of branches is L, L = {1, 2, ..., M}. In the absence of faults, the static safety domain of the power system is defined on the node active injection space, as shown in formula (1):

[0052]

[0053] Where P i is the active power output of system node i; P i min and P i max are the lower and upper limits of active output of system node i respectively; is the safety region coefficient of the power injection into node i by the power flow constraint of branch l; L is the set of branches, L = {1, 2, ..., M}; is the maximum active power value that branch l can withstand.

[0054] For branch l, its power flow is shown in formula (2):

[0055]

[0056] In the formula, It represents the safety region coefficient of the power injected into node i by the power flow constraint of branch l.

[0057] For branch k, its power flow is shown in formula (3):

[0058]

[0059] In the formula, It represents the safety region coefficient of the power injection into node i due to the power flow constraint of branch k.

[0060] In this embodiment, in step S2, the static safety domain coefficient of the power system in a fault-free scenario is used to represent the degree of power flow transfer caused by the set N-1 fault; the correction amount of the static safety domain coefficient of the power system in a fault-free scenario caused by the power flow transfer caused by the set N-1 fault is obtained by calculation.

[0061] Specifically, let the nodes at both ends of branch k be (m, n) respectively. When branch k is disconnected, focus on the static safety domain coefficient of branch l. According to the definition of power transfer factor, the safety domain coefficient of node i actually represents the power transfer factor between node i and the system balance node. Therefore, the power transfer factor can be represented by the safety domain coefficient.

[0062]

[0063] Where PTDF m,n,l is the power transfer distribution factor of the node pair (m, n) on branch l expressed by the safety region boundary coefficient; PTDF m,n,k is the power transfer distribution factor of the node pair (m, n) on branch k expressed by the safety region boundary coefficient; The safety region coefficient of the power injected into node m by the power flow constraint of branch l; The safety region coefficient of the power injected into node n by the power flow constraint of branch l; The safety region coefficient of the power injected into node m by the power flow constraint of branch k; is the safety region coefficient of the power injected into node n by the power flow constraint of branch k.

[0064] Formulas (4) and (5) are the power flow transfer distribution factors of node pair (m, n) for branch l and branch k expressed by the safety region boundary coefficients respectively.

[0065]

[0066] Formula (6) is the disconnection distribution factor of branch k to branch l expressed by the safety region boundary coefficient, that is, the degree of power flow transfer caused by setting N-1 fault.

[0067] Combining equations (2), (3) and (6), the relationship between the power flow of line l and the node injection power under the N-1 fault of line k can be derived, that is, the correction amount of the power flow transfer caused by the assumption of N-1 fault to the static safety region coefficient of the power system in the fault-free scenario, and its expression is shown in equation (7):

[0068]

[0069] Where P l br is the flow of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch k.

[0070] In this embodiment, in step S3, the static safety region coefficient of the power system in the set N-1 fault scenario is calculated based on the correction amount of the static safety region coefficient of the power system in the no-fault scenario.

[0071] Specifically, according to the definition of power system power flow safety region, under the condition of line k fault, the safety region coefficient of line l power flow constraint on node i is as shown in formula (8):

[0072]

[0073] In the formula, It is the static safety domain coefficient of the power system under the set N-1 fault scenario.

[0074] In a possible embodiment, a specific example is provided as follows:

[0075] like Figure 2 The figure shows the IEEE 24-node system and the schematic fault location;

[0076] The steps to obtain the static safety domain coefficient of the IEEE 24-node system in a fault scenario are as follows:

[0077] T1. For a given power system, let it contain N+1 nodes and M branches. The nodes are numbered from 0 to N, node 0 is a balance node, and the set of nodes other than the balance node is B = {1, 2, ..., N}; the branches are numbered from 1 to M, and the set of branches is L, L = {1, 2, ..., M}. In the absence of faults, the static safety domain of the power system is defined on the node active injection space, as shown in formula (1):

[0078]

[0079] Where P i is the active power output of system node i; P i min and P i max are the lower and upper limits of active output of system node i respectively; is the safety region coefficient of the power injection into node i by the power flow constraint of branch l; L is the set of branches, L = {1, 2, ..., M}; is the maximum active power value that branch l can withstand.

[0080] For branch l, its power flow is shown in formula (2):

[0081]

[0082] In the formula, It represents the safety region coefficient of the power injected into node i by the power flow constraint of branch l.

[0083] For branch k, its power flow is shown in formula (3):

[0084]

[0085] In the formula, It represents the safety region coefficient of the power injection into node i due to the power flow constraint of branch k.

[0086] T2. Assume that the nodes at both ends of branch k are (m, n) respectively. When branch k is disconnected, pay attention to the static safety domain coefficient of branch l. According to the definition of power transfer factor, the safety domain coefficient of node i actually represents the power transfer factor between node i and the system balance node. Therefore, the power transfer factor can be represented by the safety domain coefficient.

[0087]

[0088] Where PTDF m,n,l is the power transfer distribution factor of the node pair (m, n) on branch l expressed by the safety region boundary coefficient; PTDF m,n,k is the power transfer distribution factor of the node pair (m, n) on branch k expressed by the safety region boundary coefficient; The safety region coefficient of the power injected into node m by the power flow constraint of branch l; The safety region coefficient of the power injected into node n by the power flow constraint of branch l; The safety region coefficient of the power injected into node m by the power flow constraint of branch k; is the safety region coefficient of the power injected into node n by the power flow constraint of branch k.

[0089] Formulas (4) and (5) are the power flow transfer distribution factors of node pair (m, n) for branch l and branch k expressed by the safety region boundary coefficients respectively.

[0090]

[0091] Formula (6) is the disconnection distribution factor of branch k to branch l expressed by the safety region boundary coefficient, that is, the degree of power flow transfer caused by setting N-1 fault.

[0092] For the IEEE 24-bus system in the figure, the thermal stability safety boundary constraint of line 1-2 is as shown in formula (7):

[0093]

[0094] The thermal stability safety boundary constraint of line 1-3 is shown in formula (8):

[0095]

[0096] Combining equations (2), (3) and (6), the relationship between the power flow of line l and the node injection power under the N-1 fault of line k can be derived, that is, the correction amount of the power flow transfer caused by the assumption of N-1 fault to the static safety region coefficient of the power system in the fault-free scenario, and its expression is shown in equation (9):

[0097]

[0098] Where P l br is the flow of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch k.

[0099] T3. According to the definition of power system power flow safety region, under the condition of line k fault, the safety region coefficient of line l power flow constraint on node i is as shown in formula (10):

[0100]

[0101] In the formula, It is the static safety domain coefficient of the power system under the set N-1 fault scenario.

[0102]

[0103] For the IEEE 24-node system in the figure, when line 1-3 fails, the thermal stability safety boundary constraint of line 1-2 in the N-1 scenario is shown in formula (11).

[0104] In summary, the present invention calculates and obtains the static safety domain coefficient of the power system in a fault-free scenario based on the network parameters of the power system; uses the static safety domain coefficient of the power system in a fault-free scenario to indicate the degree of power flow transfer caused by the set N-1 fault; obtains the correction amount of the static safety domain coefficient of the power system in a fault-free scenario by the power flow transfer caused by the set N-1 fault by calculation; and calculates and obtains the static safety domain coefficient of the power system in the set N-1 fault scenario based on the correction amount of the static safety domain coefficient of the power system in the fault-free scenario. Based on the static safety domain coefficient in a fault-free scenario, the present invention proposes a correction method for the safety domain coefficient in a fault scenario to realize the rapid generation of the static safety domain coefficient of the power system in the N-1 fault scenario. Based on the parameters of the safety domain constraint equation obtained in the fault-free base state, the power flow transfer factor is determined by the safety domain coefficient. Based on the safety domain coefficient obtained in the base state, the safety domain coefficient of the system corresponding to the N-1 fault is calculated under different line conditions to obtain the thermal stability safety domain constraint, thereby realizing the rapid calculation of the thermal stability safety domain under the N-1 fault. The safety domain coefficients and constraints obtained under different faults can also be used as a reference for N-1 fault scanning to obtain the vulnerable links of the system, providing an effective reference for further determining the safety and stability of the system and avoiding cascading failures. The present invention starts from the rapid generation of the static safety domain coefficient of the power system in the N-1 fault scenario, and looks for the vulnerable links of the power system to ensure the safe and reliable operation of the power system; the present invention uses the safety domain coefficient of the fault-free scenario to generate the static safety domain coefficient of the power system in the N-1 fault scenario. It only needs to store a set of original data to generate the static safety domain coefficients of all required fault scenarios, which can effectively avoid the storage and call problems of the safety domain coefficients of high-dimensional and multi-fault scenarios.

[0105] It should be noted that the method of the embodiment of the present disclosure can be performed by a single device, such as a computer or a server. The method of the present embodiment can also be applied in a distributed scenario and completed by multiple devices cooperating with each other. In the case of such a distributed scenario, one of the multiple devices can only perform one or more steps in the method of the embodiment of the present disclosure, and the multiple devices will interact with each other to complete the described method.

[0106] It should be noted that the above describes some embodiments of the present disclosure. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the above embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0107] Example 2

[0108] See also Figure 3 Embodiment 2 of the present invention further provides a device for correcting static safety domain coefficient of a power system in an N-1 fault scenario, comprising:

[0109] The no-fault static safety domain coefficient acquisition module 001 is used to calculate and obtain the static safety domain coefficient of the power system in a no-fault scenario according to the network parameters of the power system;

[0110] The no-fault static safety domain coefficient correction value acquisition module 002 is used to use the static safety domain coefficient of the power system in a no-fault scenario to indicate the degree of power flow transfer caused by the set N-1 fault; and obtain the correction value of the static safety domain coefficient of the power system in a no-fault scenario by the power flow transfer caused by the set N-1 fault through calculation;

[0111] The N-1 fault static safety domain coefficient acquisition module 003 is used to calculate the static safety domain coefficient of the power system in the set N-1 fault scenario according to the correction amount of the static safety domain coefficient of the power system in the no-fault scenario.

[0112] In this embodiment, in the non-fault static safety domain coefficient acquisition module 001, the expression of the static safety domain coefficient of the power system in a non-fault scenario is:

[0113]

[0114] Where P i is the active power output of system node i; P i min and P i max are the lower and upper limits of active output of system node i respectively; is the safety region coefficient of the power injection into node i by the power flow constraint of branch l; L is the set of branches, L = {1, 2, ..., M}; is the maximum active power value that branch l can bear; B is the set of nodes outside the balancing node, B = {1, 2, ..., N}.

[0115] In this embodiment, in the fault-free static safety domain coefficient correction amount acquisition module 002, in the process of using the static safety domain coefficient of the power system in the fault-free scenario to represent the degree of power flow transfer caused by the setting N-1 fault, the static safety domain coefficient of the power system in the fault-free scenario represents the disconnection power flow transfer distribution factor of branch k to branch l; the expression of the disconnection power flow transfer distribution factor of branch k to branch l is:

[0116]

[0117] Where PTDFm,n,l is the power transfer distribution factor of the node pair (m, n) on branch l expressed by the safety region boundary coefficient; PTDF m,n,k is the power transfer distribution factor of the node pair (m, n) on branch k expressed by the safety region boundary coefficient; The safety region coefficient of the power injected into node m by the power flow constraint of branch l; The safety region coefficient of the power injected into node n by the power flow constraint of branch l; The safety region coefficient of the power injected into node m by the power flow constraint of branch k; is the safety region coefficient of the power injected into node n by the power flow constraint of branch k.

[0118] In this embodiment, in the fault-free static safety domain coefficient correction amount acquisition module 002, in the process of obtaining the correction amount of the static safety domain coefficient of the power system in the fault-free scenario caused by the power flow transfer caused by the set N-1 fault by calculation, the correction amount is represented by the relationship between the power flow of branch l and the injected power of node i under the set N-1 fault; the relationship between the power flow of branch l and the injected power of node i is expressed as follows:

[0119]

[0120] Where P l br is the flow of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch k.

[0121] In this embodiment, in the N-1 fault static safety domain coefficient acquisition module 003, the static safety domain coefficient expression of the power system under the set N-1 fault scenario is:

[0122]

[0123] In the formula, It is the static safety domain coefficient of the power system under the set N-1 fault scenario.

[0124] It should be noted that the information interaction, execution process and other contents between the modules of the above-mentioned system are based on the same concept as the method embodiment in Example 1 of the present application, and the technical effects they bring are the same as those of the method embodiment of the present application. For specific contents, please refer to the description in the method embodiment shown above in the present application, and will not be repeated here.

[0125] Example 3

[0126] Embodiment 3 of the present invention provides a non-transitory computer-readable storage medium, in which a program code for a method for correcting a static safety domain coefficient of an electric power system under an N-1 fault scenario is stored. The program code includes instructions for executing embodiment 1 or any possible implementation thereof, a method for correcting a static safety domain coefficient of an electric power system under an N-1 fault scenario.

[0127] The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or a data center that includes one or more available media. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)).

[0128] Example 4

[0129] Embodiment 4 of the present invention provides an electronic device, including: a memory and a processor;

[0130] The processor and the memory communicate with each other via a bus; the memory stores program instructions that can be executed by the processor, and the processor calls the program instructions to execute a method for correcting the static safety domain coefficient of an electric power system in an N-1 fault scenario in accordance with Example 1 or any possible implementation thereof.

[0131] Specifically, the processor can be implemented by hardware or by software. When implemented by hardware, the processor can be a logic circuit, an integrated circuit, etc.; when implemented by software, the processor can be a general-purpose processor implemented by reading software codes stored in a memory. The memory can be integrated in the processor or can be located outside the processor and exist independently.

[0132] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable systems. The computer instructions can be stored in a computer-readable storage medium, or transmitted from a computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center.

[0133] Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general computing system, they can be concentrated on a single computing system, or distributed on a network composed of multiple computing systems, and optionally, they can be implemented by a program code executable by a computing system, so that they can be stored in a storage system and executed by the computing system, and in some cases, the steps shown or described can be executed in a different order than here, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

[0134] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A method for correcting static safety region coefficient of power system in N-1 fault scenario, characterized in that: include: According to the network parameters of the power system, the static safety domain coefficient of the power system in a fault-free scenario is calculated; The static safety region coefficient of the power system in a no-fault scenario is used to indicate the degree of power flow transfer caused by a set N-1 fault; Obtaining by calculation a correction amount of the static safety region coefficient of the power system in a no-fault scenario caused by the power flow transfer caused by the set N-1 fault; According to the obtained correction amount of the static safety region coefficient of the power system in the no-fault scenario, the static safety region coefficient of the power system in the set N-1 fault scenario is calculated.

2. According to the method for correcting the static safety region coefficient of an N-1 fault scenario power system in claim 1, it is characterized in that: The expression of the static safety domain coefficient of the power system in a fault-free scenario is: Where P i is the active power output of system node i; P i min and P i max are the lower and upper limits of active output of system node i respectively; is the safety region coefficient of the power injection into node i by the power flow constraint of branch l; L is the set of branches, L = {1, 2, ..., M}; is the maximum active power value that branch l can bear; B is the set of nodes outside the balancing node, B = {1, 2, ..., N}.

3. According to the method for correcting the static safety region coefficient of an N-1 fault scenario power system in claim 2, it is characterized in that: In the process of using the static safety domain coefficient of the power system in a no-fault scenario to express the degree of power flow transfer caused by setting N-1 faults, the static safety domain coefficient of the power system in a no-fault scenario is used to express the disconnection power flow transfer distribution factor of branch k to branch l; the expression of the disconnection power flow transfer distribution factor of branch k to branch l is: Where PTDF m,n,l is the power transfer distribution factor of the node pair (m, n) on branch l expressed by the safety region boundary coefficient; PTDF m,n,k is the power transfer distribution factor of the node pair (m, n) on branch k expressed by the safety region boundary coefficient; The safety region coefficient of the power injected into node m by the power flow constraint of branch l; The safety region coefficient of the power injected into node n by the power flow constraint of branch l; The safety region coefficient of the power injected into node m by the power flow constraint of branch k; is the safety region coefficient of the power injected into node n by the power flow constraint of branch k.

4. According to the method for correcting the static safety region coefficient of an N-1 fault scenario power system in claim 3, it is characterized in that: In the process of obtaining the correction amount of the static safety domain coefficient of the power system under the non-fault scenario caused by the power flow transfer caused by the set N-1 fault by calculation, the correction amount is represented by the relationship between the power flow of branch l and the injected power of node i under the set N-1 fault; the relationship between the power flow of branch l and the injected power of node i is expressed as follows: Where P l br is the flow of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch k.

5. According to the method for correcting the static safety region coefficient of an N-1 fault scenario power system of claim 4, it is characterized in that: The static safety domain coefficient expression of the power system under the above-mentioned N-1 fault scenario is: In the formula, It is the static safety domain coefficient of the power system under the set N-1 fault scenario.

6. A static safety region coefficient correction device for an N-1 fault scenario power system, using a static safety region coefficient correction method for an N-1 fault scenario power system according to any one of claims 1 to 5, characterized in that: include: A fault-free static safety domain coefficient acquisition module is used to calculate and obtain the static safety domain coefficient of the power system in a fault-free scenario according to the network parameters of the power system; A module for obtaining a correction amount of a static safety region coefficient without faults is used to use the static safety region coefficient of the power system in a non-fault scenario to indicate the degree of power flow transfer caused by a set N-1 fault; Obtaining by calculation a correction amount of the static safety region coefficient of the power system in a no-fault scenario caused by the power flow transfer caused by the set N-1 fault; The N-1 fault static safety domain coefficient acquisition module is used to calculate the static safety domain coefficient of the power system under the set N-1 fault scenario based on the correction amount of the static safety domain coefficient of the power system under the fault-free scenario.

7. The device for correcting static safety region coefficient of power system in N-1 fault scenario according to claim 6 is characterized in that: In the fault-free static safety domain coefficient acquisition module, the expression of the static safety domain coefficient of the power system in a fault-free scenario is: Where P i is the active power output of system node i; P i min and P i max are the lower and upper limits of active output of system node i respectively; is the safety region coefficient of the power injection into node i by the power flow constraint of branch l; L is the set of branches, L = {1, 2, ..., M}; is the maximum active power value that branch l can bear; B is the set of nodes outside the balancing node, B = {1, 2, ..., N}.

8. The static safety region coefficient correction device for an N-1 fault scenario power system according to claim 7, characterized in that: In the fault-free static safety domain coefficient correction amount acquisition module, in the process of using the static safety domain coefficient of the power system in a fault-free scenario to represent the degree of power flow transfer caused by setting N-1 faults, the disconnection power flow transfer distribution factor of branch k to branch l is represented by the static safety domain coefficient of the power system in a fault-free scenario; the expression of the disconnection power flow transfer distribution factor of branch k to branch l is: Where PTDF m,n,l is the power transfer distribution factor of the node pair (m, n) on branch l expressed by the safety region boundary coefficient; PTDF m,n,k is the power transfer distribution factor of the node pair (m, n) on branch k expressed by the safety region boundary coefficient; The safety region coefficient of the power injected into node m by the power flow constraint of branch l; The safety region coefficient of the power injected into node n by the power flow constraint of branch l; The safety region coefficient of the power injected into node m by the power flow constraint of branch k; is the safety region coefficient of the power injected into node n by the power flow constraint of branch k.

9. The device for correcting static safety region coefficient of power system in N-1 fault scenario according to claim 8, characterized in that: In the fault-free static safety domain coefficient correction amount acquisition module, in the process of obtaining the correction amount of the static safety domain coefficient of the power system in the fault-free scenario caused by the power flow transfer caused by the set N-1 fault by calculation, the correction amount is expressed by the relationship between the power flow of branch l and the injected power of node i under the set N-1 fault; the relationship between the power flow of branch l and the injected power of node i is expressed as: Where P l br is the flow of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch l; is the safety region coefficient of the power injected into node i by the power flow constraint of branch k.

10. The device for correcting static safety region coefficient of power system in N-1 fault scenario according to claim 9, characterized in that: In the N-1 fault static safety domain coefficient acquisition module, the static safety domain coefficient expression of the power system under the set N-1 fault scenario is: In the formula, It is the static safety domain coefficient of the power system under the set N-1 fault scenario.

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