A method for identifying cascading failures in a power system and related equipment

Abstract

The embodiment of the present invention provides a method for identifying cascading failures of a power system and related equipment, wherein the method includes: obtaining multiple cascading failure paths of a target power system, and constructing at least one cascading failure event tree based on each cascading failure path, wherein the cascading failure event tree is composed of multiple cascading failure paths including the same starting element, and for each cascading failure event tree: according to the identifiers of each element of the cascading failure event tree and each cascading failure path, respectively calculating the key indicator parameters of each starting element and the correlation indicator parameters between each adjacent element, determining the starting element whose key indicator parameter is not less than a first preset threshold and other elements whose correlation indicator parameter is not less than a second preset threshold as fragile elements, wherein the other elements are electrical elements other than the starting element in each cascading failure path. The present invention realizes accurate identification of cascading failures of a power system.

Description

Technical Field

[0001] The present invention relates to the field of power system fault analysis, and in particular to a method for identifying cascading faults in a power system and related equipment. Background Art

[0002] With the increasing interconnection of power networks, the complexity of power systems has increased significantly, and the risk of large-scale power outages caused by faults in power systems has also increased. In order to prevent the risk of large-scale power outages in power systems, the existing "Guidelines for the Safety and Stability of Power Systems" sets a three-level safety and stability standard for power systems. However, the existing three-level safety and stability standards are mainly set for large-scale power outages caused by single faults in power systems. For chain failures caused by the failure of a certain component causing other related components to stop operating, the existing three-level safety and stability standards cannot accurately identify and block them. And because chain failures are mostly hidden faults in the early stages, they are not easy to detect in the early stages. The risk of large-scale power outages caused by chain failures is higher than the risk of large-scale power outages caused by single faults. Therefore, how to accurately identify chain failures in power systems has become an urgent problem to be solved. Summary of the invention

[0003] The purpose of the embodiment of the present invention is to provide a method for identifying cascading failures in a power system and related equipment to accurately identify cascading failures in a power system. The specific technical solution is as follows:

[0004] A method for identifying cascading failures in a power system, the method comprising:

[0005] Obtaining multiple cascading failure paths of the target power system, and constructing at least one cascading failure event tree based on each cascading failure path, wherein the cascading failure event tree is composed of multiple cascading failure paths including the same starting element;

[0006] For each cascading failure event tree: according to the identifiers of each component and each cascading failure path of the cascading failure event tree, the key index parameters of each starting component and the correlation index parameters between each adjacent component are calculated respectively;

[0007] The starting element whose key indicator parameter is not less than a first preset threshold and other elements whose correlation indicator parameter is not less than a second preset threshold are determined as fragile elements, wherein the other elements are electrical elements other than the starting element in each chain failure path.

[0008] Optionally, the calculation process of the key indicator parameters includes:

[0009] For each starting element: screening out at least one cascading failure path matching the identifier of the starting element;

[0010] By formula:

[0011]

[0012] Calculate the critical indicator parameter CM(l) of the starting element l, wherein s is a cascading failure path in the cascading failure event tree, ES is a set of cascading failure paths in the cascading failure event tree, I(s|l) is a first preset indicative function used to determine whether there is an identifier matching the identifier of the starting element l in the cascading failure path s, and CM max The value of is the total number of multiple chain failure paths matched by the identifier of the key element in the chain failure event tree, and the key element is the starting element whose identifier matches the largest number of chain failure paths.

[0013] Optionally, the calculation process of the correlation index parameter includes:

[0014] For each adjacent element:

[0015] By formula:

[0016]

[0017] Calculate the correlation index parameter IM(g, h) between the adjacent elements, wherein g is one of the adjacent elements, h is another element that is in the same chain failure path as g and is adjacent to g, seq is a chain failure path sequence in the chain failure event tree, I(g, h|seq) is a second preset indicative function, used to determine whether g and h are in seq, and IM g is the total number of cascading failure paths starting with g.

[0018] Optionally, the process of obtaining multiple cascading failure paths of the target power system includes:

[0019] Obtaining power flow calculation parameters of the target power system;

[0020] Based on the power flow calculation parameters, a preset power system simulation model is used to simulate power system operation faults, and electrical components with primary faults and secondary faults are marked, wherein the secondary fault is caused by the primary fault, and there is a corresponding relationship between the secondary fault and the primary fault;

[0021] Determine the electrical component having the primary fault as the starting component, and determine the electrical component having the secondary fault corresponding to the primary fault as the other component;

[0022] A plurality of cascading failure paths of the target power system are obtained, wherein the cascading failure path is a power path including one of the starting elements and at least one of the other elements, and the secondary failure of the other elements in the cascading failure path corresponds to the primary failure of the starting element.

[0023] Optionally, the method further includes:

[0024] A fault blocking strategy matching the identifier of the fragile component is called from a preset database.

[0025] A system for identifying cascading failures in a power system, the system comprising:

[0026] The data construction unit is used to obtain multiple cascading failure paths of the target power system and construct at least one cascading failure event tree based on each cascading failure path, wherein the cascading failure event tree is composed of multiple cascading failure paths including the same starting element.

[0027] The parameter calculation unit is used to calculate the key index parameters of each starting element and the correlation index parameters between each adjacent element for each chain failure event tree according to the identifiers of each element and each chain failure path of the chain failure event tree.

[0028] The component identification unit is used to determine the starting component whose key indicator parameter is not less than a first preset threshold and other components whose correlation indicator parameter is not less than a second preset threshold as fragile components, wherein the other components are electrical components other than the starting component in each chain failure path.

[0029] Optionally, when calculating the key indicator parameter, the parameter calculation unit is set to:

[0030] For each starting element: screening out at least one cascading failure path matching the identifier of the starting element;

[0031] By formula:

[0032]

[0033] Calculate the critical indicator parameter CM(l) of the starting element l, wherein s is a cascading failure path in the cascading failure event tree, ES is a set of cascading failure paths in the cascading failure event tree, I(s|l) is a first preset indicative function used to determine whether there is an identifier matching the identifier of the starting element l in the cascading failure path s, and CM maxThe value of is the total number of multiple chain failure paths matched by the identifier of the key element in the chain failure event tree, and the key element is the starting element whose identifier matches the largest number of chain failure paths.

[0034] Optionally, when calculating the correlation indicator parameter, the parameter calculation unit is set to:

[0035] For each adjacent element:

[0036] By formula:

[0037]

[0038] Calculate the correlation index parameter IM(g, h) between the adjacent elements, wherein g is one of the adjacent elements, h is another element that is in the same chain failure path as g and is adjacent to g, seq is a chain failure path sequence in the chain failure event tree, I(g, h|seq) is a second preset indicative function, used to determine whether g and h are in seq, and IM g is the total number of cascading failure paths starting with g.

[0039] Optionally, when obtaining multiple cascading failure paths of the target power system, the data construction unit is configured to:

[0040] Obtain power flow calculation parameters of the target power system.

[0041] Based on the power flow calculation parameters, a preset power system simulation model is used to simulate power system operation faults, and electrical components with primary faults and secondary faults are marked, wherein the secondary fault is caused by the primary fault, and there is a corresponding relationship between the secondary fault and the primary fault;

[0042] Determine the electrical component having the primary fault as the starting component, and determine the electrical component having the secondary fault corresponding to the primary fault as the other component;

[0043] A plurality of cascading failure paths of the target power system are obtained, wherein the cascading failure path is a power path including one of the starting elements and at least one of the other elements, and the secondary failure of the other elements in the cascading failure path corresponds to the primary failure of the starting element.

[0044] Optionally, the power system cascading failure identification system further includes:

[0045] The strategy calling unit is used to call the fault blocking strategy matching the identifier of the fragile component from a preset database.

[0046] A device for identifying cascading failures in a power system, the device comprising:

[0047] processor;

[0048] A memory for storing instructions executable by the processor.

[0049] The processor is configured to execute the instructions to implement any of the above methods for identifying cascading failures in a power system.

[0050] A computer-readable storage medium, when the instructions in the computer-readable storage medium are executed by a processor of a power system cascading failure identification device, enables the identification device to execute any of the above-mentioned power system cascading failure identification methods.

[0051] The method for identifying cascading failures in a power system and related equipment provided by the embodiment of the present invention can accurately calibrate the components corresponding to a series of cascading failures caused by the failure of a certain component in the power system by introducing a cascading failure event tree. At the same time, by introducing key indicator parameters, the degree of harm to the power system when each electrical component fails is quantified, thereby accurately identifying the key components in the power system that are prone to failures and cause large-scale power outages. Finally, by introducing the safety and stability threshold of the power system and comparing the safety and stability threshold with the preset threshold, the present invention improves the screening accuracy of fragile components compared to the manual judgment method of the prior art. Thereby improving the accurate identification of each electrical component involved in the cascading failure in the power system. It can be seen that the present invention realizes the accurate identification of cascading failures in the power system.

[0052] Of course, it is not necessary to achieve all of the advantages described above at the same time to implement any product or method of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 paying creative work.

[0054] Figure 1 A flowchart of a method for identifying cascading failures in a power system provided by an embodiment of the present invention;

[0055] Figure 2 A schematic diagram of a cascading failure event tree provided for an optional embodiment of the present invention;

[0056] Figure 3 A block diagram of a power system cascading failure identification system provided for another optional embodiment of the present invention;

[0057] Figure 4 A block diagram of a device for identifying cascading failures in a power system is provided as another optional embodiment of the present invention. DETAILED DESCRIPTION

[0058] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0059] The embodiment of the present invention provides a method for identifying cascading failures in a power system, such as Figure 1 As shown, the identification method includes:

[0060] S101. Obtain multiple cascading failure paths of a target power system, and construct at least one cascading failure event tree based on each cascading failure path, wherein the cascading failure event tree is composed of multiple cascading failure paths including a same starting element.

[0061] Optionally, in an optional embodiment of the present invention, the above-mentioned cascading failure event tree is a fault tree (Fault Tree Analysis, FTA) that characterizes the relationship between the failures of components when a cascading failure occurs in the power system. In actual application scenarios, a power system usually includes a large number of electrical components, and there are different and complex connection relationships between different electrical components. As a result, when a component fails, it is impossible to efficiently and accurately find out the electrical components within the scope of the fault. The fault tree describes the cause-and-effect relationship between events in the system through event symbols, logic gate symbols, and transfer symbols. Therefore, the present invention, by introducing the above-mentioned cascading failure event tree, can accurately calibrate the components corresponding to a series of cascading failures caused by the failure of a certain component in the power system. Thereby improving the subsequent recognition accuracy of vulnerable components.

[0062] In order to facilitate the understanding of the above cascading failure event tree, an optional embodiment of the present invention is specifically described here:

[0063] like Figure 2The figure shows a schematic diagram of a cascading failure event tree. The circles numbered 1 to 6 in the figure represent multiple electrical components in a power system. The one-way arrows in the figure represent the connection relationship between the starting electrical component and the downstream electrical component. For the convenience of description, it is assumed that Figure 2 When an electrical component in a circuit is in a fault state, it will only affect its downstream electrical components.

[0064] If the electrical component numbered 1 is the above-mentioned starting component, when the starting component fails, Figure 2 The cascading fault time tree shown includes a first fault path, a second fault path, and a third fault path. The first fault path includes electrical components numbered 1, 2, and 4. The second fault path includes electrical components numbered 1, 2, and 5. The third fault path includes electrical components numbered 1, 3, and 6.

[0065] If the electrical component numbered 2 is the above-mentioned starting component, when the starting component fails, Figure 2 The cascading fault time tree shown includes a fourth fault path and a fifth fault path, wherein the fourth fault path includes electrical components numbered 2 and 4, and the fifth fault path includes electrical components numbered 2 and 5.

[0066] S102, for each cascading failure event tree: according to the identifiers of each component and each cascading failure path of the cascading failure event tree, respectively calculate the key index parameters of each starting component and the correlation index parameters between each adjacent component.

[0067] Optionally, in an optional embodiment of the present invention, the above critical metrics (CM) parameters can be used to characterize the degree of harm to the power system when the starting element fails. For example: Assume that there are three possible chain failure paths in the power system, two of which are caused by the first element and the other is caused by the second element. Then the critical metrics parameter of the first element is two-thirds, and the critical metrics parameter of the second element is one-third.

[0068] The existing power system simulation model can only identify the specific electrical components that have failed. It is impossible to accurately identify the degree and scope of the impact of the failure of the electrical component on the power system. Therefore, the present invention introduces the above-mentioned key indicator parameters to quantify the degree of harm to the power system when each electrical component fails, thereby accurately identifying the key components in the power system that are prone to failure and cause large-scale power outages.

[0069] Optionally, in another optional embodiment of the present invention, the above-mentioned correlation index (InteractionsMetrics, IM) can be used to characterize the degree to which the electrical components associated with an electrical component are affected when a fault occurs in the electrical component. Since there are many types of faults caused by different electrical components in actual application scenarios, the scope and degree of impact caused by different types of faults are also different. For example, when the loop current is too large and the fuse is short-circuited, the motor current will be too large. Both excessive motor current and motor jamming will cause the motor to overheat. However, it is obvious that the harm caused by motor jamming to the motor is higher than the harm caused by excessive motor current. Therefore, the present invention introduces correlation indicators to quantify the degree of impact of faults between adjacent components, thereby realizing accurate identification of other components in the power system that are susceptible to the failure of associated components and cause chain failures.

[0070] S103: Determine the starting component whose key indicator parameter is not less than the first preset threshold and other components whose correlation indicator parameter is not less than the second preset threshold as fragile components, wherein the other components are electrical components other than the starting component in each chain failure path.

[0071] It should be noted that the setting method of the above-mentioned first preset threshold and the above-mentioned second preset threshold can be to obtain the fault path caused by each component in a traversal manner, and the proportion of all fault paths in the current system. After arranging the components in order from large to small according to the proportion value, according to the needs of the actual application scenario, the proportion value with the smallest value among the top-ranked multiple electrical components is determined as the above-mentioned first preset threshold and the second preset threshold. The specific values ​​of the above-mentioned first preset threshold and the second preset threshold can be set by yourself according to different application scenarios. The present invention does not impose too many restrictions on the specific values ​​and setting methods of the above-mentioned two preset thresholds.

[0072] Optionally, in an optional embodiment of the present invention, the fragile component can be an electrical component in the target power system that is prone to failure and the failure can easily lead to a large-scale power outage, or it can be an electrical component that is susceptible to failure of other electrical components and causes a cascading failure, and can easily lead to a large-scale power outage. By comparing the safety and stability threshold with the preset threshold, the present invention improves the screening accuracy of fragile components compared to the manual judgment method of the prior art. This improves the accurate identification of various electrical components involved in cascading failures in the power system.

[0073] By introducing a chain failure event tree, the present invention can accurately calibrate the components corresponding to a series of chain failures caused by the failure of a certain component in the power system. At the same time, by introducing key indicator parameters, the degree of harm to the power system when each electrical component fails can be quantified, thereby accurately identifying the key components in the power system that are prone to failure and cause large-scale power outages. Finally, by introducing a safety and stability threshold of the power system and comparing the safety and stability threshold with the preset threshold, the present invention improves the screening accuracy of fragile components compared to the manual judgment method of the prior art. This improves the accurate identification of each electrical component involved in the chain failure in the power system. It can be seen that the present invention realizes the accurate identification of chain failures in the power system.

[0074] Optional, key indicator parameter calculation process, including:

[0075] For each starting element: screen out at least one cascading failure path that matches the identifier of the starting element.

[0076] By formula:

[0077]

[0078] Calculate the critical indicator parameter CM(l) of the starting element l, where s is a cascading failure path in the cascading failure event tree, ES is the set of cascading failure paths in the cascading failure event tree, I(s|l) is a first preset indicative function used to determine whether there is an identifier in the cascading failure path s that matches the identifier of the starting element l, and CM max The value of is the total number of multiple chain failure paths matched by the identifier of the key element in the chain failure event tree. The key element is the starting element with the largest number of chain failure paths matched by the identifier.

[0079] Optionally, in an optional embodiment of the present invention, the preset characteristic function is used to characterize whether an event occurs or not, and corresponds to a two-value function of 0 and 1. For example, for the first preset characteristic function, when there is an identifier matching the identifier of the starting element 1 in the chain failure path s, the output result of the first preset characteristic function is 1. If not, the output result is 0.

[0080] It should be noted that the above formula represents the number of chain failure paths caused by different starting elements when a primary failure occurs. The larger the above key indicator parameter is, the more chain failure paths are generated when the starting element has a primary failure, and the greater the impact range is.

[0081] Optionally, the calculation process of the above correlation indicator parameters includes:

[0082] For each adjacent element:

[0083] By formula:

[0084]

[0085] Calculate the correlation index parameter IM(g, h) between the adjacent elements, where g is one of the adjacent elements, h is another element that is in the same cascading failure path as g and is adjacent to g, seq is a cascading failure path sequence in the cascading failure event tree, I(g, h|seq) is a second preset indicative function used to determine whether g and h are in seq, IM g is the total number of cascading failure paths starting with element g.

[0086] It should be noted that once a fault occurs in the power system, it is necessary to analyze the evolution of the system's cascading faults and find the electrical components and lines that may fail at the next level to prevent the occurrence and expansion of cascading faults. Therefore, through the above formula, the probability of two adjacent electrical components failing one after another can be obtained. Then the electrical components with a high probability of secondary failure can be determined.

[0087] Optionally, the process of obtaining multiple cascading failure paths of the target power system includes:

[0088] Obtain the power flow calculation parameters of the target power system.

[0089] Based on the power flow calculation parameters, the preset power system simulation model is used to simulate the power system operation faults, and the electrical components with primary faults and secondary faults are marked. Among them, the secondary faults are caused by the primary faults, and there is a corresponding relationship between the secondary faults and the primary faults.

[0090] An electrical component having a primary fault is determined as a starting component, and an electrical component having a secondary fault corresponding to the primary fault is determined as another component.

[0091] A plurality of cascading failure paths of a target power system are obtained, wherein a cascading failure path is a power path including a starting element and at least one other element, and a secondary failure of the other elements in the cascading failure path corresponds to a primary failure of the starting element.

[0092] Optionally, in an optional embodiment of the present invention, the power flow calculation parameters may include various types of power system power flow parameters, such as target power system topology, voltage, frequency, power angle, active power, reactive power, etc.

[0093] Optional, as above Figure 1The method shown also includes:

[0094] From the preset database, the fault blocking strategy matching the identifier of the vulnerable component is called.

[0095] Optionally, in an optional embodiment of the present invention, the above-mentioned fault blocking strategy can be a strategy for blocking cascading failures based on the type, function and other parameters of the vulnerable element. For example, if the above-mentioned vulnerable element is an isolating switch, its function in the target power system is to switch lines. If a power failure occurs in its upper-level element, its corresponding fault blocking strategy is to control the isolating switch to perform a line switching operation so that the downstream power grid can switch lines.

[0096] Corresponding to the above method embodiment, the present invention also provides a system for identifying cascading failures in a power system, such as Figure 3 As shown, the identification system includes:

[0097] The data construction unit 301 is used to obtain multiple cascading failure paths of the target power system, and construct at least one cascading failure event tree based on each cascading failure path, wherein the cascading failure event tree is composed of multiple cascading failure paths including the same starting element.

[0098] The parameter calculation unit 302 is used to calculate the key index parameters of each starting element and the correlation index parameters between each adjacent element for each cascading failure event tree according to the identifiers of each element and each cascading failure path of the cascading failure event tree.

[0099] The component identification unit 303 is used to determine the starting component whose key indicator parameter is not less than the first preset threshold and other components whose correlation indicator parameter is not less than the second preset threshold as fragile components, wherein the other components are electrical components other than the starting component in each chain failure path.

[0100] Optionally, when calculating the key indicator parameters, the parameter calculation unit 302 is set to:

[0101] For each starting element: screen out at least one cascading failure path that matches the identifier of the starting element.

[0102] By formula:

[0103]

[0104] Calculate the critical indicator parameter CM(l) of the starting element l, where s is a cascading failure path in the cascading failure event tree, ES is a set of cascading failure paths in the cascading failure event tree, I(s|l) is a first preset indicative function used to determine whether there is an identifier in the cascading failure path s that matches the identifier of the starting element l, and CMmax The value of is the total number of multiple chain failure paths matched by the identifier of the key element in the chain failure event tree. The key element is the starting element with the largest number of chain failure paths matched by the identifier.

[0105] Optionally, when calculating the correlation index parameter, the parameter calculation unit 302 is set to:

[0106] For each adjacent element:

[0107] By formula:

[0108]

[0109] Calculate the correlation index parameter IM(g, h) between the adjacent elements, where g is one of the adjacent elements, h is another element that is in the same cascading failure path as g and is adjacent to g, seq is a cascading failure path sequence in the cascading failure event tree, I(g, h|seq) is a second preset indicative function used to determine whether g and h are in seq, IM g is the total number of cascading failure paths starting with element g.

[0110] Optionally, when obtaining multiple cascading failure paths of the target power system, the data construction unit 301 is configured as follows:

[0111] Obtain the power flow calculation parameters of the target power system.

[0112] Based on the power flow calculation parameters, the preset power system simulation model is used to simulate the power system operation faults, and the electrical components with primary faults and secondary faults are marked. Among them, the secondary faults are caused by the primary faults, and there is a corresponding relationship between the secondary faults and the primary faults.

[0113] An electrical component having a primary fault is determined as a starting component, and an electrical component having a secondary fault corresponding to the primary fault is determined as another component.

[0114] A plurality of cascading failure paths of a target power system are obtained, wherein a cascading failure path is a power path including a starting element and at least one other element, and a secondary failure of the other elements in the cascading failure path corresponds to a primary failure of the starting element.

[0115] Optional, as above Figure 3 The system shown also includes:

[0116] The strategy calling unit is used to call the fault blocking strategy matching the identifier of the vulnerable component from a preset database.

[0117] The embodiment of the present invention also provides a device for identifying cascading failures in a power system, such as Figure 4 As shown, the identification device includes:

[0118] Processor 401;

[0119] The memory 402 is used to store instructions executable by the processor 401 .

[0120] The processor 401 is configured to execute instructions to implement the above-mentioned Figure 1 The method for identifying cascading failures in a power system is shown.

[0121] The embodiment of the present invention further provides a computer-readable storage medium. When the instructions in the computer-readable storage medium are executed by a processor of a power system cascading failure identification device, the identification device can perform the above-mentioned Figure 1 The method for identifying cascading failures in a power system is shown.

[0122] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip. The memory is an example of a computer-readable medium.

[0123] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0124] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0125] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. It should also be noted that the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0126] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0127] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A method for identifying cascading failures in a power system, characterized in that: The method comprises: Obtaining multiple cascading failure paths of the target power system, and constructing at least one cascading failure event tree based on each cascading failure path, wherein the cascading failure event tree is composed of multiple cascading failure paths including the same starting element; For each cascading failure event tree: according to the identifiers of each component and each cascading failure path of the cascading failure event tree, the key index parameters of each starting component and the correlation index parameters between each adjacent component are calculated respectively; The starting element whose key indicator parameter is not less than a first preset threshold and other elements whose correlation indicator parameter is not less than a second preset threshold are determined as fragile elements, wherein the other elements are electrical elements other than the starting element in each chain failure path.

2. The method according to claim 1, characterized in that: The calculation process of the key indicator parameters includes: For each starting element: screening out at least one cascading failure path matching the identifier of the starting element; By formula: Calculate the critical indicator parameter CM(l) of the starting element l, wherein s is a cascading failure path in the cascading failure event tree, ES is a set of cascading failure paths in the cascading failure event tree, I(s|l) is a first preset indicative function used to determine whether there is an identifier matching the identifier of the starting element l in the cascading failure path s, and CM max The value of is the total number of multiple chain failure paths matched by the identifier of the key element in the chain failure event tree, and the key element is the starting element whose identifier matches the largest number of chain failure paths.

3. The method according to claim 2, characterized in that The calculation process of the correlation index parameter includes: For each adjacent element: By formula: Calculate the correlation index parameter IM(g, h) between the adjacent elements, wherein g is one of the adjacent elements, h is another element that is in the same chain failure path as g and is adjacent to g, seq is a chain failure path sequence in the chain failure event tree, I(g, h|seq) is a second preset indicative function, used to determine whether g and h are in seq, and IM g is the total number of cascading failure paths starting with g.

4. The method according to claim 1, characterized in that The process of obtaining multiple cascading failure paths of the target power system includes: Obtaining power flow calculation parameters of the target power system; Based on the power flow calculation parameters, a preset power system simulation model is used to simulate power system operation faults, and electrical components with primary faults and secondary faults are marked, wherein the secondary fault is caused by the primary fault, and there is a corresponding relationship between the secondary fault and the primary fault; Determine the electrical component having the primary fault as the starting component, and determine the electrical component having the secondary fault corresponding to the primary fault as the other component; A plurality of cascading failure paths of the target power system are obtained, wherein the cascading failure path is a power path including one of the starting elements and at least one of the other elements, and the secondary failure of the other elements in the cascading failure path corresponds to the primary failure of the starting element.

5. The method according to claim 1, characterized in that The method further comprises: A fault blocking strategy matching the identifier of the fragile component is called from a preset database.

6. A system for identifying cascading failures in a power system, characterized in that: The system comprises: A data construction unit, used for obtaining a plurality of cascading failure paths of a target power system, and constructing at least one cascading failure event tree based on each cascading failure path, wherein the cascading failure event tree is composed of a plurality of cascading failure paths including a same starting element; A parameter calculation unit is used to calculate, for each chain failure event tree: according to the identifiers of each element and each chain failure path of the chain failure event tree, respectively calculate the key index parameters of each starting element and the correlation index parameters between each adjacent element; The component identification unit is used to determine the starting component whose key indicator parameter is not less than a first preset threshold and other components whose correlation indicator parameter is not less than a second preset threshold as fragile components, wherein the other components are electrical components other than the starting component in each chain failure path.

7. The system according to claim 6, characterized in that When calculating the key indicator parameters, the parameter calculation unit is set to: For each starting element: screening out at least one cascading failure path matching the identifier of the starting element; By formula: Calculate the critical indicator parameter CM(l) of the starting element l, wherein s is a cascading failure path in the cascading failure event tree, ES is a set of cascading failure paths in the cascading failure event tree, I(s|l) is a first preset indicative function used to determine whether there is an identifier matching the identifier of the starting element l in the cascading failure path s, and CM max The value of is the total number of multiple chain failure paths matched by the identifier of the key element in the chain failure event tree, and the key element is the starting element whose identifier matches the largest number of chain failure paths.

8. The system according to claim 7, characterized in that When calculating the correlation index parameter, the parameter calculation unit is set to: For each adjacent element: By formula: Calculate the correlation index parameter IM(g, h) between the adjacent elements, wherein g is one of the adjacent elements, h is another element that is in the same chain failure path as g and is adjacent to g, seq is a chain failure path sequence in the chain failure event tree, I(g, h|seq) is a second preset indicative function, used to determine whether g and h are in seq, and IM g is the total number of cascading failure paths starting with g.

9. A device for identifying cascading failures in a power system, characterized in that: The device comprises: processor; a memory for storing instructions executable by the processor; The processor is configured to execute the instructions to implement the method for identifying cascading failures in a power system as described in any one of claims 1 to 5.

10. A computer-readable storage medium, characterized in that: When the instructions in the computer-readable storage medium are executed by a processor of a device for identifying cascading failures in a power system, the device is enabled to execute the method for identifying cascading failures in a power system as claimed in any one of claims 1 to 5.

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