A potential faulty element search method and device for wide-area backup protection

Abstract

The application discloses a kind of wide-area backup protection potential fault element search method and device, method includes: obtaining the additional network structure of fault point where line fault point is and current fault component amplitude;The current fault component amplitude is associated with the branch connected with substation in the additional network structure of fault point;According to the size relationship of current fault component amplitude of the branch connected with substation, determine fault line;From the current fault component amplitude of each element in the fault line, determine potential fault element.Compared with prior art that can only search possible fault area, the application is based on the current fault component amplitude of line to search, can greatly reduce the suspected fault line searched, to improve the efficiency of search.

Description

Technical Field

[0001] This invention relates to the field of wide-area backup protection technology, and more particularly to a method and apparatus for searching for potential faulty components in wide-area backup protection. Background Technology

[0002] The task of relay protection is to reflect the faults and abnormal operating conditions of the protected components. According to function, it can be divided into main protection and backup protection. Traditional backup protection mainly uses local single-ended quantity information for fault detection and judgment. Different protection devices can generally only coordinate and cooperate through inherent settings, resulting in poor adaptability of protection devices and complex setting coordination. When unexpected faults or abnormal operating conditions occur, it may cause protection to fail to operate, maloperate, or cascade, triggering a large-scale power outage accident across the entire network.

[0003] Existing fault area search methods can only search for possible fault areas. When there are many lines connected to the bus, a large number of suspected fault lines will be defined. Summary of the Invention

[0004] This invention provides a method and apparatus for searching potential faulty components in wide-area backup protection. The search is based on the amplitude of the current fault component of the line, which can greatly reduce the number of suspected faulty lines found.

[0005] In a first aspect, the present invention provides a method for searching potential faulty components in wide-area backup protection, comprising:

[0006] Obtain the additional network structure and current fault component amplitude of the fault point where the line fault point is located.

[0007] Associate the amplitude of the current fault component with the substation connected branch in the additional network structure of the fault point;

[0008] The faulty line is determined based on the magnitude relationship of the current fault components in the branches connected to the substation.

[0009] Potentially faulty components are identified from the current fault component amplitude of each component in the faulty circuit.

[0010] Optionally, the faulty line is determined based on the magnitude relationship of the current fault components in the branches connected to the substation, including:

[0011] Determine the maximum current fault component amplitude among all the stated current fault component amplitudes;

[0012] The substation connected to the maximum current fault component amplitude is defined as the fault line.

[0013] Optionally, before determining the faulty line based on the magnitude relationship of the current fault components in the branches connected to the substation, the method further includes:

[0014] Determine whether the fault point of the line is located on a series branch.

[0015] Optionally, determining the faulty line based on the magnitude relationship of the current fault components in the branches connected to the substation further includes:

[0016] When the line fault point is located on a series branch, the current fault component amplitude on the series branch is removed;

[0017] Determine the amplitude of the second current fault component among all the current fault component amplitudes after elimination;

[0018] The substation connected to the second-flow fault component amplitude is defined as the fault line.

[0019] Secondly, the present invention also provides a wide-area backup protection potential fault component search device, comprising:

[0020] The acquisition module is used to acquire the additional network structure and current fault component amplitude of the fault point where the line fault point is located.

[0021] The association module is used to associate the amplitude of the current fault component with the substation connected branch in the fault point additional network structure;

[0022] The fault line determination module is used to determine the fault line based on the magnitude relationship of the current fault component amplitudes of the branches connected to the substation.

[0023] A potential faulty component determination module is used to determine potential faulty components from the current fault component amplitude of each component in the faulty line.

[0024] Optionally, the fault line determination module includes:

[0025] The first maximum current fault component amplitude determination submodule is used to determine the maximum current fault component amplitude among all the current fault component amplitudes.

[0026] The first fault line determination submodule is used to define the substation connected branch corresponding to the amplitude of the maximum current fault component as the fault line.

[0027] Optionally, it also includes:

[0028] The judgment module is used to determine whether the line fault point is located on a series branch.

[0029] Optionally, the fault line determination module further includes:

[0030] The elimination submodule is used to eliminate the current fault component amplitude on the series branch when the line fault point is located on the series branch;

[0031] The second maximum current fault component amplitude determination submodule is used to determine the second current fault component amplitude among all the current fault component amplitudes after elimination.

[0032] The second fault line determination submodule is used to define the substation connected branch corresponding to the amplitude of the second flow fault component as the fault line.

[0033] A third aspect of this application provides an electronic device, the device including a processor and a memory;

[0034] The memory is used to store program code and transmit the program code to the processor;

[0035] The processor is used to execute the wide-area backup protection potential fault element search method described in the first aspect according to the instructions in the program code.

[0036] A fourth aspect of this application provides a computer-readable storage medium for storing program code for executing the wide-area backup protection potential fault element search method described in the first aspect.

[0037] As can be seen from the above technical solutions, the present invention has the following advantages:

[0038] This invention obtains the additional network structure and current fault component amplitude of the fault point; associates the current fault component amplitude with the substation connected branches in the additional network structure of the fault point; determines the faulty line based on the magnitude relationship of the current fault component amplitudes of the substation connected branches; and identifies potential faulty components from the current fault component amplitude of each component in the faulty line. Compared to existing technologies that can only search for possible fault areas, this invention searches based on the current fault component amplitude of the line, which can greatly reduce the number of suspected faulty lines found, thereby improving the search efficiency. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a flowchart illustrating the steps of a method for detecting abnormal line losses according to the present invention.

[0041] Figure 2This is a schematic diagram of the current fault component distribution according to the present invention;

[0042] Figure 3 This is a flowchart illustrating the steps of a second embodiment of the method for detecting abnormal line losses according to the present invention.

[0043] Figure 4 This is a schematic diagram of the current fault component distribution in a series configuration according to the present invention;

[0044] Figure 5 This is a structural block diagram of an embodiment of a line loss anomaly detection device according to the present invention. Detailed Implementation

[0045] This invention provides a method and apparatus for searching potential faulty components in wide-area backup protection. The search is based on the amplitude of the current fault component of the line, which can greatly reduce the number of suspected faulty lines found.

[0046] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0047] Please see Figure 1 , Figure 1 This is a flowchart illustrating the steps of a method for searching potential faulty components in wide-area backup protection according to the present invention. Specifically, it may include the following steps:

[0048] Step S101: Obtain the additional network structure and current fault component amplitude of the fault point where the line fault point is located;

[0049] Step S102: Associate the amplitude of the current fault component with the substation connected branch in the fault point additional network structure;

[0050] Step S103: Determine the faulty line based on the magnitude relationship of the current fault component amplitudes of the branches connected to the substation;

[0051] In this embodiment of the invention, among all associated branches of a single substation, the branch closest to the fault point has the largest fault current. Due to the current diversion effect of non-faulty branches, the fault component amplitude of the current in the branch closest to the fault point is the largest among the associated branches of each substation. Therefore, by comparing the current fault component amplitude of the associated branches of the substations, the branch closest to the fault point can be searched. For substations A to D, branches L1, L2, L3, L4, and L5 can be searched respectively. Generally, the number of branches closest to the fault point searched for in each substation is 1, and only one line (i.e., the actual faulty line) is searched by both substations simultaneously.

[0052] In an optional embodiment, determining the faulty line based on the magnitude relationship of the current fault components in the branches connected to the substation includes:

[0053] Determine the maximum current fault component amplitude among all the stated current fault component amplitudes;

[0054] The substation connected to the maximum current fault component amplitude is defined as the fault line.

[0055] Step S104: Determine potential faulty components from the current fault component amplitude of each component in the faulty circuit.

[0056] Please see Figure 2 , Figure 2 This is a schematic diagram of the current fault component distribution according to the present invention. When a fault occurs in the power grid, its fault-addition network can be obtained using the superposition theorem. In the fault-addition network, the faulty power source is located at the line fault point, and the current fault component flows out from the power source to both sides of the faulty line. The arrows indicate the actual direction of the current fault component. The distribution characteristics of the current fault component are: the maximum value of the branch current fault component is located on one side of the actual faulty line. When a fault occurs in the power grid, as the distance from the transmission line to the fault point increases, the amplitude of the current fault component gradually increases. Let the amplitudes of the connected branch current fault components of substation C be respectively... Due to the flow splitting effect of branches L1 and L2, we have: Similarly, the case of substation D is as follows: The fault is caused by a current fault on both sides of line L3. and The relative magnitude of the fault is affected by factors such as the location of the fault point, line impedance, and system impedance, but the larger of the two is the maximum value of the current fault component in each branch.

[0057] This invention, in its embodiments, obtains the additional network structure and current fault component amplitude of the fault point; associates the current fault component amplitude with the substation-connected branches in the additional network structure; determines the faulty line based on the magnitude relationship of the current fault component amplitudes of the substation-connected branches; and identifies potential faulty components from the current fault component amplitude of each component in the faulty line. Compared to existing technologies that can only search for possible fault areas, this invention searches based on the current fault component amplitude of the line, which can greatly reduce the number of suspected faulty lines found, thereby improving search efficiency.

[0058] Please see Figure 3 The flowchart below shows the steps of a second embodiment of the method for detecting abnormal line losses according to the present invention, specifically including:

[0059] Step S201: Obtain the additional network structure and current fault component amplitude of the fault point where the line fault point is located;

[0060] Step S202: Associate the amplitude of the current fault component with the substation connected branch in the additional network structure of the fault point;

[0061] Step S203: Determine whether the line fault point is located on a series branch;

[0062] Step S204: When the line fault point is located on a series branch, the current fault component amplitude on the series branch is removed.

[0063] Step S205: Determine the amplitude of the second current fault component among all the current fault component amplitudes after elimination;

[0064] Step S206: Define the substation connected branch corresponding to the amplitude of the second flow fault component as the fault line;

[0065] Step S207: Determine potential faulty components from the current fault component amplitude of each component in the faulty circuit.

[0066] In practical applications, substation busbars typically have a large number of associated branches, and each branch has a significant shunting effect on the current fault component. By comparing the current amplitudes of each branch, the single branch with the largest current fault component amplitude can be accurately identified, i.e., the actual faulty line. However, in some extreme cases, when the number of associated branches in a substation is small or when purely series branches exist, the shunting effect of the substation's associated branches will no longer be significant. In this case, the maximum value of the current fault component may appear not only on one side of the actual faulty line but also on the other side of other branches.

[0067] Please see Figure 4 , Figure 4This is a schematic diagram of the current fault component distribution in a series configuration according to the present invention. When the fault point is located in a series branch, the directions of the current fault components in the non-faulty line L1 and the faulty line L2 are the same as those in the series branch. Figure 2 There is no change compared to the previous period. However, due to the lack of other branch current diversion, the fault component amplitude of the current in the branch current connected to substation B has increased. and They are almost equal. At this point, if... Then the branch with the largest amplitude of the current fault component is still the actual faulty line L2; if Then there will be two branches with the largest current fault component amplitude: non-faulty line L1 and faulty line L2. Therefore, when it is determined that the line fault point is on a series path, the current fault component amplitude on the series path needs to be eliminated in advance.

[0068] However, overall, series branches and other extreme cases are rare in actual ultra-high voltage transmission networks. Therefore, by comparing the amplitude of the fault component of the branch current, the actual faulty line can be accurately identified in most cases.

[0069] The method for detecting abnormal line losses provided in this embodiment of the invention involves obtaining the additional network structure and current fault component amplitude of the fault point; associating the current fault component amplitude with the substation-connected branches in the additional network structure of the fault point; determining the faulty line based on the magnitude relationship of the current fault component amplitudes of the substation-connected branches; and identifying potential faulty components from the current fault component amplitude of each component in the faulty line. Compared to existing technologies that can only search for possible fault areas, this invention searches based on the current fault component amplitude of the line, which can greatly reduce the number of suspected faulty lines found, thereby improving the search efficiency.

[0070] Please see Figure 3 The diagram illustrates a structural block diagram of an embodiment of a wide-area backup protection potential fault component search device, which includes the following modules:

[0071] The acquisition module 301 is used to acquire the additional network structure of the fault point and the amplitude of the current fault component at the fault point of the line.

[0072] The association module 302 is used to associate the amplitude of the current fault component with the substation connected branch in the fault point additional network structure;

[0073] The fault line determination module 303 is used to determine the fault line based on the magnitude relationship of the current fault component amplitude of the branch connected to the substation.

[0074] Potential faulty component determination module 304 is used to determine potential faulty components from the current fault component amplitude of each component in the faulty line.

[0075] In an optional embodiment, the fault line determination module 303 includes:

[0076] The first maximum current fault component amplitude determination submodule is used to determine the maximum current fault component amplitude among all the current fault component amplitudes.

[0077] The first fault line determination submodule is used to define the substation connected branch corresponding to the amplitude of the maximum current fault component as the fault line.

[0078] In an optional embodiment, it further includes:

[0079] The judgment module is used to determine whether the line fault point is located on a series branch.

[0080] In an optional embodiment, the fault line determination module further includes:

[0081] The elimination submodule is used to eliminate the current fault component amplitude on the series branch when the line fault point is located on the series branch;

[0082] The second maximum current fault component amplitude determination submodule is used to determine the second current fault component amplitude among all the current fault component amplitudes after elimination.

[0083] The second fault line determination submodule is used to define the substation connected branch corresponding to the amplitude of the second flow fault component as the fault line.

[0084] This application also provides an electronic device, which includes a processor and a memory;

[0085] The memory is used to store program code and transfer the program code to the processor;

[0086] The processor is used to execute the wide-area backup protection potential fault element search method in the above method embodiment according to the instructions in the program code.

[0087] This application also provides a computer-readable storage medium for storing program code for executing the wide-area backup protection potential fault element search method in the above method embodiments.

[0088] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0089] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0090] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0091] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for executing all or part of the steps of the methods described in the various embodiments of this application through a computer device (which may be a personal computer, server, or network device, etc.). The aforementioned storage medium includes: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0092] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for searching potential faulty components in wide-area backup protection, characterized in that, include: Obtain the additional network structure and current fault component amplitude of the fault point where the line fault point is located. Associate the amplitude of the current fault component with the substation connected branch in the additional network structure of the fault point; The faulty line is determined based on the magnitude relationship of the current fault components in the branches connected to the substation. The potential faulty component is determined from the current fault component amplitude of each component in the faulty circuit; Determining the faulty line based on the magnitude relationship of the current fault components in the branches connected to the substation also includes: When the line fault point is located on a series branch, the current fault component amplitude on the series branch is removed; Determine the second largest current fault component amplitude among all the current fault component amplitudes after elimination; The substation connected to the second maximum current fault component amplitude is defined as the fault line.

2. The method for searching potential faulty components in wide-area backup protection according to claim 1, characterized in that, Based on the magnitude relationship of the current fault components in the branches connected to the substation, the faulty line is determined, including: Determine the maximum current fault component amplitude among all the stated current fault component amplitudes; The substation connected to the maximum current fault component amplitude is defined as the fault line.

3. The method for searching potential faulty components in wide-area backup protection according to claim 2, characterized in that, Before determining the faulty line based on the magnitude relationship of the current fault components in the branches connected to the substation, the following steps are also included: Determine whether the fault point of the line is located on a series branch.

4. A wide-area backup protection potential fault component search device, characterized in that, include: The acquisition module is used to acquire the additional network structure and current fault component amplitude of the fault point where the line fault point is located. The association module is used to associate the amplitude of the current fault component with the substation connected branch in the fault point additional network structure; The fault line determination module is used to determine the fault line based on the magnitude relationship of the current fault component amplitudes of the branches connected to the substation. A potential faulty component determination module is used to determine potential faulty components from the current fault component amplitude of each component in the faulty line; The fault line determination module also includes: The elimination submodule is used to eliminate the current fault component amplitude on the series branch when the line fault point is located on the series branch; The second maximum current fault component amplitude determination submodule is used to determine the second maximum current fault component amplitude among all the current fault component amplitudes after elimination. The second fault line determination submodule is used to define the substation connected branch corresponding to the amplitude of the second maximum current fault component as the fault line.

5. The wide-area backup protection potential fault component search device according to claim 4, characterized in that, The fault line determination module includes: The first maximum current fault component amplitude determination submodule is used to determine the maximum current fault component amplitude among all the current fault component amplitudes. The first fault line determination submodule is used to define the substation connected branch corresponding to the amplitude of the maximum current fault component as the fault line.

6. The wide-area backup protection potential fault component search device according to claim 5, characterized in that, Also includes: The judgment module is used to determine whether the line fault point is located on a series branch.

7. An electronic device, characterized in that, It includes a processor and a memory, the memory storing computer-readable instructions, which, when executed by the processor, perform the method as described in any one of claims 1-3.

8. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by this processor, it performs the method as described in any one of claims 1-3.

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