Power system overload safety boundary calculation method and system based on feasible space, storage medium and equipment

Abstract

The invention discloses an electric power system overload safety boundary calculation method and system based on a feasible space, a storage medium and equipment, and the method comprises the steps: obtaining the power flow distribution and power flow transfer ratio under an expected fault based on the rapid scanning of the expected fault; identifying a strong correlation branch based on the power flow transfer ratio, and generating a power system overload safety initial boundary based on the combination constraint of the strong correlation branch power flow; a feasible space of the power system is described by considering an equipment adjustable space constraint, a power balance constraint of the power system and an overload safety initial boundary constraint of the power system, and an overload safety effective boundary of the power system is further identified based on linear optimization. According to the method, accurate identification and efficient calculation of the overload safety boundary of the power system can be realized, and a decision basis is provided for day-ahead, intra-day, real-time and other multi-time scale scheduling plans and real-time control.

Description

Technical Field

[0001] The present invention relates to the technical field of power system safety and stability analysis, and in particular to a method, system, storage medium and device for calculating an overload safety boundary of a power system based on a feasible space. Background Art

[0002] The safety and stability boundary of the power system is the premise and basis for multi-time scale scheduling and real-time control, and its accuracy is directly related to the safety and economy of the power system. The overload safety boundary of the power system is an important part of the safety and stability boundary of the power system, including the base state overload safety boundary and the overload safety boundary under expected faults.

[0003] Due to the large scale of the monitored branch set (M) and the expected fault set (N) (for regional power grids, the scale is greater than 10,000), the scale of the overload safety boundary of the power system with potential risks (M+M*N) is huge. Taking all of them into consideration will seriously restrict the convergence and solution efficiency of scheduling plans and real-time control decisions. At present, the iterative solution idea of ​​"decision-making + verification" is generally adopted. First, some key boundary (key section) constraints are considered, and then the boundary constraints with risks are added round by round according to the verification results. The convergence has been improved, but the iteration efficiency still needs to be improved.

[0004] The existing key boundary (key section) identification methods mainly include two categories: one is the offline method, in which the operator recognizes the characteristics of the power grid through historical operation analysis, selects the key sections based on operation experience and natural geographical information, and may miss the key sections; the other is the online method, which is based on real-time operation mode analysis and selects the key sections according to the load rate of components under expected faults. This type of method is essentially an open-loop prediction, and its reliability is difficult to guarantee. In addition, some methods use the positional relationship of boundary constraints in a two-dimensional plane to filter redundant boundaries, but they are only applicable to a small number of boundaries that are mutually fault branches and transfer branches.

[0005] With a high proportion of new energy sources connected to the power grid, the operation mode of the new power system is complex and changeable, with obvious strong uncertainty characteristics. The flow of key sections changes dramatically and reverses frequently during the day. Multi-section and multi-mode interaction coupling makes it increasingly difficult to characterize the system boundary, and existing methods are difficult to deal with effectively. Generally, the shorter the prediction period, the higher the prediction accuracy. At time scales such as day-ahead and day-intraday, the prediction accuracy of new energy and load is higher, and the transaction and maintenance plans are basically determined. The uncertainty factors are greatly reduced. The feasible space of the system can be characterized at a certain confidence level, and the effective boundary of the system can be accurately and efficiently identified based on the feasible space of the system, thereby improving the safety and economy of the scheduling plan and real-time control of the new power system at multiple time scales such as day-ahead, day-intraday, and real-time. Summary of the invention

[0006] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0007] In view of the above existing problems, the present invention is proposed.

[0008] Therefore, the present invention provides a method, system, storage medium and device for calculating the overload safety boundary of an electric power system based on feasible space to solve the problems of insufficient reliability, practicality and timeliness of existing boundary identification and calculation methods.

[0009] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0010] In a first aspect, the present invention provides a method for calculating an overload safety boundary of a power system based on a feasible space, comprising:

[0011] Perform expected fault scans based on the preset power system operation mode to obtain the power grid flow distribution and the flow transfer ratio of the monitored branch under the expected fault;

[0012] Based on the power flow transfer ratio, strongly correlated branches are identified, and based on the combined constraints of the strongly correlated branch power flows, the initial boundary of power system overload safety is generated;

[0013] Considering the equipment adjustable space constraints, power system power balance constraints and power system overload safety initial boundary constraints, the effective boundary of power system overload safety is identified through linear optimization calculation.

[0014] As a preferred solution of the method for calculating the overload safety boundary of a power system based on feasible space described in the present invention, wherein:

[0015] The power system overload safety includes base state overload safety and overload safety under anticipated faults.

[0016] As a preferred solution of the method for calculating the overload safety boundary of a power system based on feasible space described in the present invention, wherein:

[0017] The power system overload safety includes base state overload safety and overload safety under anticipated faults.

[0018] As a preferred solution of the method for calculating the overload safety boundary of a power system based on feasible space described in the present invention, wherein:

[0019] The method of performing a predicted fault scan for a preset power system operation mode to obtain a power grid flow distribution and a flow transfer ratio of a monitoring branch under a predicted fault includes the following steps:

[0020] According to the preset power system operation mode, the factor table and sensitivity matrix of the base state network are obtained by calculating the base state power flow distribution;

[0021] According to the preset power system operation mode, the power flow distribution under the expected fault is calculated based on the factor table and sensitivity matrix of the base state network, the compensation method and sensitivity analysis method;

[0022] According to the preset power system operation mode, the power flow transfer ratio of the monitored branch is calculated based on the power flow distribution under the base state and the expected fault conditions;

[0023] The power flow transfer ratio of the monitoring branch is expressed as:

[0024]

[0025] Among them, K FT is the expected fault set, l k Open the branch for the expected fault k, L MT To monitor the branch set, Disconnect branch l for expected fault k k The power transfer ratio of the monitoring branch l is: To disconnect the branch k The ground state active power, P LN,l , They are the base state active power of monitored branch l and the active power under expected fault k respectively.

[0026] As a preferred solution of the method for calculating the overload safety boundary of a power system based on feasible space described in the present invention, wherein:

[0027] The method of identifying strongly correlated branches based on the power flow transfer ratio and generating the initial boundary of power system overload safety based on the combined constraints of the strongly correlated branch power flows comprises the following steps:

[0028] For each anticipated fault, the absolute value of the power flow transfer ratio is greater than the critical transfer ratio. The monitoring branch is taken as the main transfer branch, and the expected fault disconnection branch and its main transfer branch are taken as strongly related branches;

[0029] According to the adjusted power system operation mode, the active power of the main transfer branch under the expected fault is calculated based on the linear combination formula of the base state active power of the strongly correlated branches;

[0030] According to the adjusted power system operation mode, the initial safety boundary of overload under expected fault is generated based on the active power constraint under expected fault of the main transfer branch.

[0031] According to the adjusted power system operation mode, the initial overload safety boundary b under the base state is generated based on the base state active power constraint of the monitoring branch.l ;

[0032] The critical transfer ratio It is expressed as:

[0033]

[0034] The active power under the expected fault of the main transfer branch is expressed as:

[0035]

[0036] The initial boundary of overload safety under the expected fault It is expressed as:

[0037]

[0038] The overload safety initial boundary b in the base state l It is expressed as:

[0039]

[0040] The adjusted power system operation mode refers to the power system operation mode generated by adjusting the node injection of active and reactive power under the condition that the network topology of the preset power system operation mode remains unchanged;

[0041] in, is the main transfer branch set under the expected fault k; To disconnect the branch k The ground state active power, P′ LN,l , are the base state active power of monitoring branch l and the active power under expected fault k, P LN,MAX,l , P LN,MAX,FT,l are the base state active power limit and the active power limit under expected fault of monitoring branch l respectively. To disconnect the branch k The base state active power limit.

[0042] As a preferred solution of the method for calculating the overload safety boundary of a power system based on feasible space described in the present invention, wherein:

[0043] The method of considering the equipment adjustable space constraint, the power system power balance constraint, and the power system overload safety initial boundary constraint, and identifying the power system overload safety effective boundary through linear optimization calculation, comprises the following steps:

[0044] Optimize the calculation of the initial safety boundaries of each overload under both the expected fault and the base state;

[0045] Define the initial boundary of overload safety under expected faults The maximum and minimum values ​​of the two objective functions are considered, and the equipment adjustable space constraints, power system power balance constraints, and power system overload safety initial boundary constraints are considered. According to the optimization results, the effective boundary of overload safety under expected faults is identified;

[0046] Define the initial boundary b of overload safety in the base state l The two objective functions of maximum and minimum values ​​consider the equipment adjustable space constraints, power system power balance constraints, and power system overload safety initial boundary constraints, and identify the effective boundary of overload safety under the base state based on the optimization results;

[0047] The initial boundary of overload safety under the expected fault The maximum value of the objective function is expressed as:

[0048]

[0049] The initial boundary of overload safety under the expected fault The minimum value of the objective function is expressed as:

[0050]

[0051] The initial boundary of overload safety under the expected fault The constraints are expressed as:

[0052]

[0053] The effective boundary of overload safety under the expected fault is expressed as:

[0054]

[0055] The overload safety initial boundary b in the base state l The maximum value of the objective function is expressed as:

[0056] max(P′ LN,l ),l∈L MT

[0057] The overload safety initial boundary b in the base state l The minimum value of the objective function is expressed as:

[0058] min(P′ LN,l ),l∈L MT

[0059] The overload safety initial boundary b in the base state l The objective function constraint is expressed as:

[0060]

[0061] The overload safety effective boundary under the base state is expressed as:

[0062]

[0063] Among them, X P is the set of active adjustable devices, P i is the active power of adjustable equipment i under the preset power system operation mode, P i,MIN , P i,MAX , ΔP i They are respectively the lower limit, upper limit and adjustment amount of the active power of adjustable device i.

[0064] As a preferred solution of the method for calculating the overload safety boundary of a power system based on feasible space described in the present invention, wherein:

[0065] The specific calculation formula of the base state active power of the disconnected branch and the monitored branch in the adjusted power system operation mode is expressed as:

[0066]

[0067] Among them, L FT K FT The set of all disconnected branches in , To disconnect or monitor the base state active power of branch l2 in the adjusted power system operation mode, To disconnect or monitor the base state active power of branch l2 under the preset power system operation mode, It is the active sensitivity of the adjustable device i to the disconnected or monitored branch l2 under the preset power system operation mode.

[0068] In a second aspect, the present invention provides a power system overload safety boundary calculation system based on feasible space, comprising:

[0069] The anticipated fault scanning module is used to perform anticipated fault scanning for the preset power system operation mode, and obtain the power flow distribution of the power grid and the power flow transfer ratio of the monitoring branch under the anticipated fault;

[0070] An initial boundary generation module is used to identify strongly correlated branches based on the power flow transfer ratio, and to generate an initial boundary for overload safety of the power system based on the combined constraints of the power flows of the strongly correlated branches;

[0071] The effective boundary identification module is used to consider the equipment adjustable space constraints, the power system power balance constraints, and the power system overload safety initial boundary constraints, and identify the power system overload safety effective boundary through linear optimization calculation.

[0072] In a third aspect, the present invention provides a computing device, comprising:

[0073] Memory, used to store programs;

[0074] A processor is used to execute the computer executable instructions, which, when executed by the processor, implement the steps of the method for calculating the overload safety boundary of the power system based on the feasible space.

[0075] In a fourth aspect, the present invention provides a computer-readable storage medium, comprising: when the program is executed by a processor, the steps of implementing the method for calculating the overload safety boundary of an electric power system based on a feasible space are implemented.

[0076] The beneficial effects of the present invention: The present invention takes into account the equipment adjustable space constraints, the power system power balance constraints, and the power system overload safety initial boundary constraints to characterize the feasible space of the power system, and identifies the positive and reverse over-limit risks of the power system overload safety initial boundary based on linear optimization within the feasible space, which can achieve rapid and accurate identification of the effective boundary of the power system overload safety, and is more reliable and practical than traditional methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0078] Figure 1 A schematic diagram of the basic flow of a method for calculating an overload safety boundary of an electric power system based on feasible space provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0079] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0080] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0081] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0082] The present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0083] At the same time, in the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper, lower, inner and outer" are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0084] In the present invention, unless otherwise clearly specified and limited, the terms "install, connect, connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0085] Example 1

[0086] Reference Figure 1 , which is an embodiment of the present invention, provides a method for calculating the overload safety boundary of a power system based on a feasible space, comprising:

[0087] S1: Perform a predicted fault scan for the preset power system operation mode to obtain the power flow distribution of the power grid and the power flow transfer ratio of the monitoring branch under the predicted fault;

[0088] In the embodiment of the present application, the overload safety of the power system includes base state overload safety and overload safety under anticipated faults.

[0089] In the embodiment of the present application, a predicted fault scan is performed for a preset power system operation mode to obtain the power grid flow distribution and the power flow transfer ratio of the monitoring branch under the predicted fault, including the following steps:

[0090] According to the preset power system operation mode, the factor table and sensitivity matrix of the base state network are obtained by calculating the base state power flow distribution;

[0091] According to the preset power system operation mode, the power flow distribution under the expected fault is calculated based on the factor table and sensitivity matrix of the base state network, the compensation method and sensitivity analysis method;

[0092] According to the preset power system operation mode, the power flow transfer ratio of the monitored branch is calculated based on the power flow distribution under the base state and the expected fault conditions;

[0093] In the embodiment of the present application, the power flow transfer ratio of the monitoring branch is expressed as:

[0094]

[0095] Among them, K FT is the expected fault set, l k Open the branch for the expected fault k, L MT To monitor the branch set, Disconnect branch l for expected fault k k The power transfer ratio of the monitoring branch l is: To disconnect the branch k The ground state active power, P LN,l , They are the base state active power of monitored branch l and the active power under expected fault k respectively.

[0096] S2: Based on the power flow transfer ratio, identify the strongly correlated branches, and generate the initial boundary of power system overload safety based on the combined constraints of the strongly correlated branch power flows;

[0097] In an embodiment of the present application, based on the power flow transfer ratio, strongly correlated branches are identified, and based on the combined constraints of the strongly correlated branch flows, an initial boundary of power system overload safety is generated, including the following steps:

[0098] For each anticipated fault, the absolute value of the power flow transfer ratio is greater than the critical transfer ratio. The monitoring branch is taken as the main transfer branch, and the expected fault disconnection branch and its main transfer branch are taken as strongly related branches;

[0099] According to the adjusted power system operation mode, the active power of the main transfer branch under the expected fault is calculated based on the linear combination formula of the base state active power of the strongly correlated branches;

[0100] According to the adjusted power system operation mode, the initial safety boundary of overload under expected fault is generated based on the active power constraint under expected fault of the main transfer branch.

[0101] According to the adjusted power system operation mode, the initial overload safety boundary b under the base state is generated based on the base state active power constraint of the monitoring branch. l ;

[0102] In the embodiment of the present application, the critical transfer ratio It is expressed as:

[0103]

[0104] In the embodiment of the present application, the active power under the expected fault of the main transfer branch is expressed as:

[0105]

[0106] In the embodiment of the present application, the initial boundary of overload safety under the expected fault It is expressed as:

[0107]

[0108] In the embodiment of the present application, the overload safety initial boundary b in the base state l It is expressed as:

[0109]

[0110] in, is the main transfer branch set under the expected fault k; To disconnect the branch k The ground state active power, P′ LN,l , are the base state active power of monitoring branch l and the active power under expected fault k, P LN,MAX,l , P LN,MAX,FT,l are the base state active power limit and the active power limit under expected fault of monitoring branch l respectively. To disconnect the branch k The base state active power limit.

[0111] The adjusted power system operation mode refers to a power system operation mode generated by injecting active and reactive power by adjusting nodes under the condition that the network topology of the preset power system operation mode remains unchanged.

[0112] S3: Considering the equipment adjustable space constraints, power system power balance constraints, and power system overload safety initial boundary constraints, the effective boundary of the power system overload safety is identified through linear optimization calculation.

[0113] In the embodiment of the present application, considering the equipment adjustable space constraint, the power system power balance constraint, and the power system overload safety initial boundary constraint, the power system overload safety effective boundary is identified through linear optimization calculation, including the following steps:

[0114] Optimize the calculation of the initial safety boundaries of each overload under both the expected fault and the base state;

[0115] Define the initial boundary of overload safety under expected faults The maximum and minimum values ​​of the two objective functions are considered, considering the equipment adjustable space constraints, power system power balance constraints, power system, overload safety initial boundary constraints ( Except for (except), identify the effective boundary of overload safety under expected faults based on the optimization results;

[0116] Define the initial boundary b of overload safety in the base state l The maximum and minimum values ​​of the two objective functions are considered, considering the equipment adjustable space constraint, the power system power balance constraint, and the power system overload safety initial boundary constraint (b l Except for (except), identify the overload safety effective boundary under the base state according to the optimization results;

[0117] In the embodiment of the present application, the initial boundary of overload safety under the expected fault The maximum value of the objective function is expressed as:

[0118]

[0119] In the embodiment of the present application, the initial boundary of overload safety under the expected fault The minimum value of the objective function is expressed as:

[0120]

[0121] In the embodiment of the present application, the initial boundary of overload safety under the expected fault The constraints are expressed as:

[0122]

[0123] In the embodiment of the present application, the effective boundary of overload safety under the expected fault is expressed as:

[0124]

[0125] In the embodiment of the present application, the overload safety initial boundary b in the base state l The maximum value of the objective function is expressed as:

[0126] max(P′ LN,l ),l∈L MT

[0127] In the embodiment of the present application, the overload safety initial boundary b in the base state l The minimum value of the objective function is expressed as:

[0128] min(P′ LN,l ),l∈LMT

[0129] In the embodiment of the present application, the overload safety initial boundary b in the base state l The objective function constraint is expressed as:

[0130]

[0131] In the embodiment of the present application, the overload safety effective boundary in the base state is expressed as:

[0132]

[0133] Among them, X P is the set of active adjustable devices, P i is the active power of adjustable equipment i under the preset power system operation mode, P i,MIN , P i,MAX , ΔP i They are respectively the lower limit, upper limit and adjustment amount of the active power of adjustable device i.

[0134] In the embodiment of the present application, the base state active power of the disconnected branch and the monitored branch in the adjusted power system operation mode is specifically calculated as follows:

[0135]

[0136] Among them, L FT K FT The set of all disconnected branches in , To disconnect or monitor the base state active power of branch l2 in the adjusted power system operation mode, To disconnect or monitor the base state active power of branch l2 under the preset power system operation mode, It is the active sensitivity of the adjustable device i to the disconnected or monitored branch l2 under the preset power system operation mode.

[0137] It should be noted that it is difficult for existing methods to take into account both the efficiency and reliability of boundary calculation at the same time. However, this method, based on comprehensive consideration of strongly correlated constraints, quickly and effectively screens and identifies effective boundaries based on linear optimization, which can achieve accurate identification and efficient calculation of overload safety boundaries.

[0138] This embodiment also provides a power system overload safety boundary calculation system based on feasible space, including:

[0139] The anticipated fault scanning module is used to perform anticipated fault scanning for the preset power system operation mode, and obtain the power flow distribution of the power grid and the power flow transfer ratio of the monitoring branch under the anticipated fault;

[0140] An initial boundary generation module is used to identify strongly correlated branches based on the power flow transfer ratio, and to generate an initial boundary for overload safety of the power system based on the combined constraints of the power flows of the strongly correlated branches;

[0141] The effective boundary identification module is used to consider the equipment adjustable space constraints, the power system power balance constraints, and the power system overload safety initial boundary constraints, and identify the power system overload safety effective boundary through linear optimization calculation.

[0142] Furthermore, it also includes:

[0143] Memory, used to store programs;

[0144] A processor is used to load the program to execute the method for calculating the overload safety boundary of the power system based on the feasible space.

[0145] This embodiment also provides a computer-readable storage medium storing a program, which, when executed by a processor, implements the method for calculating the overload safety boundary of an electric power system based on a feasible space.

[0146] The storage medium proposed in this embodiment and the method for calculating the overload safety boundary of the power system based on the feasible space proposed in the above embodiment belong to the same inventive concept. The technical details not described in detail in this embodiment can be referred to the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0147] Through the above description of the implementation methods, the technicians in the relevant field can clearly understand that the present invention can be implemented by means of software and necessary general hardware, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ReadOnly, Memory, ROM), random access memory (RandomAccess Memory, RAM), flash memory (FLASH), hard disk or optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform the methods of various embodiments of the present invention.

[0148] Example 2

[0149] Referring to Table 1, an embodiment of the present invention provides a method for calculating the overload safety boundary of a power system based on a feasible space. In order to verify its beneficial effects, comparison results of two schemes are provided.

[0150] Table 1 Comparison table

[0151]

[0152]

[0153] As can be seen from Table 1, the existing methods are more dependent on historical data and manual experience, and have certain limitations, especially in dealing with the complexity and uncertainty brought about by the high proportion of new energy access in new power systems. However, our invention comprehensively considers multiple constraints and uses anticipated fault scanning and flow transfer ratio to identify strongly correlated branches, which can more comprehensively identify key sections and improve the safety and economy of the power system through linear optimization calculations. This solution has higher reliability and practicality in dealing with complex power systems.

[0154] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for calculating the overload safety boundary of a power system based on feasible space, characterized in that: include: Perform expected fault scans based on the preset power system operation mode to obtain the power grid flow distribution and the flow transfer ratio of the monitored branch under the expected fault; Based on the power flow transfer ratio, strongly correlated branches are identified, and based on the combined constraints of the strongly correlated branch power flows, the initial boundary of power system overload safety is generated; Considering the equipment adjustable space constraints, power system power balance constraints and power system overload safety initial boundary constraints, the effective boundary of power system overload safety is identified through linear optimization calculation.

2. The method for calculating the overload safety boundary of a power system based on feasible space according to claim 1, characterized in that: The power system overload safety includes base state overload safety and overload safety under anticipated faults.

3. The method for calculating the overload safety boundary of a power system based on feasible space according to claim 1, characterized in that: The method of performing a predicted fault scan for a preset power system operation mode to obtain a power grid flow distribution and a flow transfer ratio of a monitoring branch under a predicted fault includes the following steps: According to the preset power system operation mode, the factor table and sensitivity matrix of the base state network are obtained by calculating the base state power flow distribution; According to the preset power system operation mode, the power flow distribution under the expected fault is calculated based on the factor table and sensitivity matrix of the base state network, the compensation method and sensitivity analysis method; According to the preset power system operation mode, the power flow transfer ratio of the monitored branch is calculated based on the power flow distribution under the base state and the expected fault conditions; The power flow transfer ratio of the monitoring branch is expressed as: Among them, K FT is the expected fault set, l k Open the branch for the expected fault k, L MT To monitor the branch set, Disconnect branch l for expected fault k k The power transfer ratio of the monitoring branch l is: To disconnect the branch k The ground state active power, P LN,l , They are the base state active power of monitored branch k and the active power under anticipated fault k respectively.

4. The method for calculating the overload safety boundary of a power system based on feasible space according to claim 3, characterized in that: The method of identifying strongly correlated branches based on the power flow transfer ratio and generating the initial boundary of power system overload safety based on the combined constraints of the strongly correlated branch power flows comprises the following steps: For each anticipated fault, the absolute value of the power flow transfer ratio is greater than the critical transfer ratio. The monitoring branch is taken as the main transfer branch, and the expected fault disconnection branch and its main transfer branch are taken as strongly related branches; According to the adjusted power system operation mode, the active power of the main transfer branch under the expected fault is calculated based on the linear combination formula of the base state active power of the strongly correlated branches; According to the adjusted power system operation mode, the initial safety boundary of overload under expected fault is generated based on the active power constraint under expected fault of the main transfer branch. According to the adjusted power system operation mode, the initial overload safety boundary b under the base state is generated based on the base state active power constraint of the monitoring branch. l ; The critical transfer ratio It is expressed as: The active power under the expected fault of the main transfer branch is expressed as: The initial boundary of overload safety under the expected fault It is expressed as: The overload safety initial boundary b in the base state l It is expressed as: The adjusted power system operation mode refers to the power system operation mode generated by adjusting the node injection of active and reactive power under the condition that the network topology of the preset power system operation mode remains unchanged; in, is the main transfer branch set under the expected fault k; To disconnect the branch k The ground state active power, P′ LN,l , are the base state active power of monitoring branch l and the active power under expected fault k, P LN,MAX,l , P LN,MAX,FT,l are the base state active power limit and the active power limit under expected fault of monitoring branch l respectively. To disconnect the branch k The base state active power limit.

5. The method for calculating the overload safety boundary of a power system based on feasible space according to claim 4, characterized in that: The method of considering the equipment adjustable space constraint, the power system power balance constraint, and the power system overload safety initial boundary constraint, and identifying the power system overload safety effective boundary through linear optimization calculation, comprises the following steps: Optimize the calculation of the initial safety boundaries of each overload under both the expected fault and the base state; Define the initial boundary of overload safety under expected faults The maximum and minimum values ​​of the two objective functions are considered, and the equipment adjustable space constraints, power system power balance constraints, and power system overload safety initial boundary constraints are considered. The effective boundary of overload safety under expected faults is identified according to the optimization results; Define the initial boundary b of overload safety in the base state l The two objective functions of maximum and minimum values ​​consider the equipment adjustable space constraints, power system power balance constraints, and power system overload safety initial boundary constraints, and identify the effective boundary of overload safety under the base state based on the optimization results; The initial boundary of overload safety under the expected fault The maximum value of the objective function is expressed as: The initial boundary of overload safety under the expected fault The minimum value of the objective function is expressed as: The initial boundary of overload safety under the expected fault The constraints are expressed as: The effective boundary of overload safety under the expected fault is expressed as: The overload safety initial boundary b in the base state l The maximum value of the objective function is expressed as: max(P′ LN,l ),l∈L MT The overload safety initial boundary b in the base state l The minimum value of the objective function is expressed as: min(P′ LN,l ),l∈L MT The overload safety initial boundary b in the base state l The objective function constraint is expressed as: The overload safety effective boundary under the base state is expressed as: Among them, X P is the set of active adjustable devices, P i is the active power of adjustable equipment i under the preset power system operation mode, P i,MIN , P i,MAX , ΔP i They are respectively the lower limit, upper limit and adjustment amount of the active power of adjustable device i.

6. The method for calculating the overload safety boundary of a power system based on feasible space according to claim 5, characterized in that: The specific calculation formula of the base state active power of the disconnected branch and the monitored branch in the adjusted power system operation mode is expressed as: Among them, L FT K FT The set of all disconnected branches in , To disconnect or monitor the base state active power of branch l2 in the adjusted power system operation mode, To disconnect or monitor the base state active power of branch l2 under the preset power system operation mode, It is the active sensitivity of the adjustable device i to the disconnected or monitored branch l2 under the preset power system operation mode.

7. A system based on the method for calculating the overload safety boundary of a power system based on feasible space according to claim 1, characterized in that: The anticipated fault scanning module is used to perform anticipated fault scanning for the preset power system operation mode, and obtain the power flow distribution of the power grid and the power flow transfer ratio of the monitoring branch under the anticipated fault; An initial boundary generation module is used to identify strongly correlated branches based on the power flow transfer ratio, and to generate an initial boundary for overload safety of the power system based on the combined constraints of the power flows of the strongly correlated branches; The effective boundary identification module is used to consider the equipment adjustable space constraints, the power system power balance constraints, and the power system overload safety initial boundary constraints, and identify the power system overload safety effective boundary through linear optimization calculation.

8. An electronic device, characterized in that: include: Memory, used to store programs; A processor is used to load the program to execute the steps of the method for calculating the overload safety boundary of an electric power system based on feasible space as described in any one of claims 1 to 6.

9. A computer-readable storage medium storing a program, characterized in that: When the program is executed by a processor, the steps of the method for calculating the overload safety boundary of an electric power system based on a feasible space as described in any one of claims 1 to 6 are implemented.

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