Power transmission line fault state index determination method and apparatus, and electronic device

Abstract

The invention discloses a power transmission line fault state index determination method and device and electronic equipment. The method comprises the steps that a target index determination instruction is received, and the target index determination instruction is an instruction used for determining the fault state of a target power transmission line; in response to the target index determination instruction, operation parameters corresponding to the target power transmission line are determined, and the operation parameters comprise traveling wave parameters; determining an initial fault state index corresponding to the target power transmission line according to the traveling wave parameter; determining a power parameter fluctuation index corresponding to the target power transmission line according to the operation parameters; and determining a target fault state index corresponding to the target power transmission line according to the electric power parameter fluctuation index and the initial fault state index. According to the invention, the technical problem that the fault state of the power transmission line is determined inaccurately due to the complexity of the power transmission line when the fault state of the power transmission line is determined by adopting a traveling wave protection method is solved.

Description

Technical Field

[0001] The present invention relates to the field of data processing, and in particular, to a method, apparatus, and electronic device for determining a fault state index of a transmission line. Background Art

[0002] In the related art, in a transmission line, a traveling wave protection method is used to determine the fault state of the transmission line. However, due to the complexity of the transmission line, such as the line length, branch structure, and environmental factors along the line, etc., the traveling wave signal is easily interfered during the transmission process, resulting in the technical problem that the determination of the fault state of the transmission line is inaccurate.

[0003] In view of the above problems, no effective solution has been proposed yet. Summary of the Invention

[0004] Embodiments of the present invention provide a method, apparatus, and electronic device for determining a fault state index of a transmission line, so as to at least solve the technical problem that when using the traveling wave protection method to determine the fault state of the transmission line, due to the complexity of the transmission line, the determination of the fault state of the transmission line is inaccurate.

[0005] According to one aspect of the embodiments of the present invention, a method for determining a fault state index of a transmission line is provided, including: receiving a target index determination instruction, where the target index determination instruction is an instruction for determining the fault state of a target transmission line; in response to the target index determination instruction, determining operating parameters corresponding to the target transmission line, where the operating parameters include traveling wave parameters; determining an initial fault state index corresponding to the target transmission line according to the traveling wave parameters; determining a power parameter fluctuation index corresponding to the target transmission line according to the operating parameters; and determining a target fault state index corresponding to the target transmission line according to the power parameter fluctuation index and the initial fault state index.

[0006] Optionally, the determining the operating parameters corresponding to the target transmission line includes: determining a plurality of measurement point position parameters corresponding to the target transmission line; determining measurement point operating parameters corresponding to the plurality of measurement point position parameters respectively according to the plurality of measurement point position parameters; and determining the operating parameters corresponding to the target transmission line according to the measurement point operating parameters corresponding to the plurality of measurement point position parameters respectively.

[0007] Optionally, determining the target fault state index corresponding to the target transmission line according to the power parameter fluctuation index and the initial fault state index includes: determining the fault location corresponding to the target transmission line; determining the voltage fluctuation index corresponding to the fault location according to the power parameter fluctuation index; and determining the target fault state index corresponding to the fault location according to the voltage fluctuation index and the initial fault state index.

[0008] Optionally, determining the fault location corresponding to the target transmission line includes: when the traveling wave parameters include a speed parameter and arrival time parameters corresponding to multiple detection points respectively, determining the fault direction according to the arrival time parameters corresponding to the multiple detection points, where the corresponding arrival time parameter is used to represent the time when the traveling wave is detected at the corresponding detection point, and the speed parameter is used to represent the propagation speed of the traveling wave; determining the fault distance according to the arrival time parameters corresponding to the multiple detection points and the speed parameter; and determining the fault location corresponding to the target transmission line according to the fault direction and the fault distance.

[0009] Optionally, determining the fault direction according to the arrival time parameters corresponding to the multiple detection points includes: determining arrival order parameters corresponding to the multiple arrival time parameters according to the arrival time parameters corresponding to the multiple detection points; and determining the fault direction according to the arrival order parameters corresponding to the multiple arrival time parameters.

[0010] Optionally, determining the target fault state index corresponding to the fault location according to the voltage fluctuation index and the initial fault state index includes: determining a to-be-verified fault state index corresponding to the target transmission line according to the voltage fluctuation index and the initial fault state index; determining a current fluctuation index corresponding to the fault location according to the power parameter fluctuation index; and determining the target fault state index corresponding to the fault location according to the current fluctuation index and the to-be-verified fault state index.

[0011] Optionally, determining the operating parameter corresponding to the target transmission line includes: determining a partition parameter of the target transmission line, where the partition parameter is used to represent the partition of the power system where the target transmission line is located; determining the line characteristics corresponding to the target transmission line according to the partition parameter and the target transmission line; and determining the operating parameter corresponding to the target transmission line according to the line characteristics.

[0012] According to one aspect of an embodiment of the present invention, there is provided an apparatus for determining a fault state index of a transmission line, including: a receiving module configured to receive a target index determination instruction, where the target index determination instruction is an instruction for determining the fault state of a target transmission line; a response module configured to, in response to the target index determination instruction, determine an operating parameter corresponding to the target transmission line, where the operating parameter includes a traveling wave parameter; a first determination module configured to determine an initial fault state index corresponding to the target transmission line according to the traveling wave parameter; a second determination module configured to determine a power parameter fluctuation index corresponding to the target transmission line according to the operating parameter; and a third determination module configured to determine a target fault state index corresponding to the target transmission line according to the power parameter fluctuation index and the initial fault state index.

[0013] According to one aspect of an embodiment of the present invention, there is provided an electronic device, including: a processor; and a memory for storing executable instructions of the processor; wherein the processor is configured to execute the instructions to implement the method for determining a fault state index of a transmission line according to any one of the above.

[0014] According to one aspect of an embodiment of the present invention, there is provided a computer-readable storage medium, when instructions in the computer-readable storage medium are executed by a processor of an electronic device, enabling the electronic device to execute the method for determining a fault state index of a transmission line according to any one of the above.

[0015] In an embodiment of the present invention, a target index determination instruction is received, where the target index determination instruction is an instruction for determining the fault state of a target transmission line; in response to the target index determination instruction, an operating parameter corresponding to the target transmission line is determined, where the operating parameter includes a traveling wave parameter; an initial fault state index corresponding to the target transmission line is determined according to the traveling wave parameter; a power parameter fluctuation index corresponding to the target transmission line is determined according to the operating parameter; and a target fault state index corresponding to the target transmission line is determined according to the power parameter fluctuation index and the initial fault state index. The power parameter fluctuation index can reflect the variation of electrical quantities such as current and voltage when a fault occurs on the line, and the traveling wave parameter can capture the propagation characteristics of the traveling wave. By combining the two, the line state during fault occurrence can be analyzed more comprehensively, thereby avoiding misjudgment or missed judgment that may be caused by a single detection method. For example, when relying solely on traveling wave protection, due to the complexity of the transmission line, the fault location accuracy may decrease. By introducing the power parameter fluctuation index, the nature and location of the fault can be further verified, improving the reliability of fault judgment, and thus solving the technical problem of inaccurate determination of the fault state of a transmission line when using the traveling wave protection method due to the complexity of the transmission line. Description of the Drawings

[0016] The accompanying drawings described herein are used to provide a further understanding of the present invention and form a part of this application. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0017] Figure 1 is a flowchart of a method for determining the fault state index of a transmission line according to an embodiment of the present invention;

[0018] Figure 2 is a schematic diagram of zone protection in an alternative embodiment of the present invention;

[0019] Figure 3 is a schematic diagram of measuring points in the protection area of a DC transformer in an alternative embodiment of the present invention;

[0020] Figure 4 is a structural block diagram of a device for determining the fault state index of a transmission line according to an embodiment of the present invention. Detailed Embodiments

[0021] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0022] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned accompanying drawings are used to distinguish similar objects and do not necessarily need to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0023] Embodiment 1

[0024] According to an embodiment of the present invention, an embodiment of a method for determining a fault state index of a transmission line is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0025] Figure 1 FIG. 1 is a flow chart of a method for determining a transmission line fault state index according to an embodiment of the present invention. Figure 1 As shown, the method comprises the following steps:

[0026] S102, receiving a target index determination instruction, wherein the target index determination instruction is an instruction for determining a fault state of a target transmission line;

[0027] In step S102 provided in the present application, a target index determination instruction is received.

[0028] Among them, a target index determination instruction is involved, and the target index determination instruction is an instruction for determining the fault state of a certain section of a specific transmission line (target transmission line). The target index determination instruction can be issued by a control system or a protection system.

[0029] Among them, the target transmission line is involved, and the target transmission line is a specific line selected as the detection object in the power system. The target transmission line is used for power transmission in the power system, and can be a line in the DC line protection zone, a line in the DC transformer protection zone, etc. For example, in a multi-terminal flexible DC distribution network system, the target transmission line can be any one or more DC lines, and a traveling wave signal is generated on the target transmission line. It is initially judged that there may be certain faults, which need to be further confirmed.

[0030] Receiving a target index determination instruction for determining the fault state of a target transmission line helps to subsequently conduct a targeted analysis of the fault state of the target transmission line, thereby helping to avoid the problem of inaccurate fault state detection in a complex line structure.

[0031] S104, in response to the target index determination instruction, determining operating parameters corresponding to the target transmission line, wherein the operating parameters include traveling wave parameters;

[0032] In step S104 provided in the present application, a target index determination instruction is responded to, and an operating parameter corresponding to the target transmission line is determined.

[0033] Among them, operating parameters are involved. The operating parameters are parameters for monitoring and recording the working state of the target transmission line during the operation of the power system. The operating parameters may include voltage, current, power, frequency, impedance, etc.

[0034] Among them, traveling wave parameters are involved. The traveling wave parameters are parameters used to reflect the characteristics of traveling wave signals. The traveling wave parameters may include the propagation speed of the traveling wave, the time difference of the traveling wave arriving at both ends of the detection points, the frequency characteristics of the traveling wave signal, etc.

[0035] By obtaining the operating parameters of the target transmission line, including traveling wave parameters, it helps to accurately reflect the operating state of the target transmission line, provides a data basis for determining the fault state of the target transmission line subsequently, and thus helps to improve the accuracy and reliability of fault state determination subsequently.

[0036] S106. Determine the initial fault state index corresponding to the target transmission line according to the traveling wave parameters;

[0037] In step S106 provided in this application, the initial fault state index corresponding to the target transmission line is determined.

[0038] Among them, the initial fault state index is involved. The initial fault state index is a quantitative index that is initially obtained based on the traveling wave parameters and reflects the fault state of the target transmission line.

[0039] By analyzing the traveling wave parameters in the target transmission line, it can accurately reflect the mutation situation of the electrical parameters during the operation of the target transmission line, and thus helps to make a quick response, initially judge the fault state of the target transmission line, and provide an analysis basis for subsequent further judgment.

[0040] S108. Determine the power parameter fluctuation index corresponding to the target transmission line according to the operating parameters;

[0041] In step S108 provided in this application, the power parameter fluctuation index corresponding to the target transmission line is determined.

[0042] Among them, the power parameter fluctuation index is involved. The power parameter fluctuation index is an index used to evaluate the fluctuation situation such as the amplitude and speed of electrical parameters such as voltage and current changing with time in the target transmission line. For example, voltage fluctuation index, current change rate index, etc.

[0043] Through the power parameter fluctuation index, the fluctuation change of the line electrical parameters is converted into specific values, providing a more intuitive and quantitative basis for fault detection, thus helping to accurately determine the change characteristics of the electrical parameters of the transmission line, and further helping to analyze whether the current power parameter fluctuation is an abnormal fluctuation.

[0044] S110. Determine a target fault status index corresponding to the target transmission line according to the power parameter fluctuation index and the initial fault status index.

[0045] In step S110 provided in this application, a target fault status index corresponding to the target transmission line is determined.

[0046] Among them, the target fault status index is involved. The target fault status index is determined by comprehensively considering the power parameter fluctuation index and the initial fault status index, and can reflect the fault status of the target transmission line. For example, the target fault status index may include whether there is a fault status, the fault location, the severity of the fault, etc.

[0047] Compared with the initial fault status index, the target fault status index considers more dimensions of information, including the preliminary judgment result based on the traveling wave parameters and the fluctuation index of electrical parameters (such as voltage and current), so as to provide a more comprehensive and reliable fault status judgment, avoiding misjudgment or missed judgment that may be brought by a single detection method.

[0048] Through the above steps S102 - S110, receive a target index determination instruction, where the target index determination instruction is an instruction for determining the fault status of the target transmission line; in response to the target index determination instruction, determine the operating parameters corresponding to the target transmission line, where the operating parameters include traveling wave parameters; according to the traveling wave parameters, determine the initial fault status index corresponding to the target transmission line; according to the operating parameters, determine the power parameter fluctuation index corresponding to the target transmission line; according to the power parameter fluctuation index and the initial fault status index, determine the target fault status index corresponding to the target transmission line. The power parameter fluctuation index can reflect the changes in electrical quantities such as current and voltage when a fault occurs in the line, and the traveling wave parameters can capture the propagation characteristics of the traveling wave. By combining the two, the line status when a fault occurs can be analyzed more comprehensively, thus avoiding misjudgment or missed judgment that may be brought by a single detection method. For example, when relying solely on traveling wave protection, due to the complexity of the transmission line, the fault location accuracy may decrease. By introducing the power parameter fluctuation index, the nature and location of the fault can be further verified, improving the reliability of fault judgment, and thus solving the technical problem that the fault status of the transmission line is not accurately determined due to the complexity of the transmission line when using the traveling wave protection method to determine the fault status of the transmission line.

[0049] As an optional embodiment, determining the operating parameters corresponding to the target transmission line includes: determining a plurality of measuring point position parameters corresponding to the target transmission line; according to the plurality of measuring point position parameters, determining the measuring point operating parameters corresponding to the plurality of measuring point position parameters respectively; according to the measuring point operating parameters corresponding to the plurality of measuring point position parameters respectively, determining the operating parameters corresponding to the target transmission line.

[0050] In this embodiment, the specific steps for determining the operating parameters corresponding to the target transmission line are described.

[0051] Among them, the measuring point position parameter is involved. The measuring point position parameter is the specific position information used to reflect the pre-set position for detecting the operating state of the transmission line in the target transmission line. The measuring point position parameter can be the position parameters of key points, the starting point of the line, the ending point of the line, etc. in the transmission line.

[0052] Among them, the measuring point operating parameter is involved. The measuring point operating parameter is measured at the measuring point position of the target transmission line and is used to reflect the operating state of the measuring point position.

[0053] In the steps involved in this embodiment, first, a plurality of measuring point position parameters corresponding to the target transmission line are determined. Then, according to the plurality of measuring point position parameters, the measuring point operating parameters corresponding to the plurality of measuring point position parameters are determined respectively. Finally, according to the measuring point operating parameters corresponding to the plurality of measuring point position parameters respectively, the operating parameters corresponding to the target transmission line are determined.

[0054] By setting the measuring point position parameters at the key points of the transmission line (such as branch points, the starting point of the line, the ending point of the line, etc.), the complex line can be divided into multiple monitorable sub-segments. This way of segmented monitoring can capture the local changes more precisely when a fault occurs, avoid misjudgment of the fault state caused by the overall complexity of the line, and then comprehensively combine the operating parameters of multiple measuring points to comprehensively reflect the operating state of the transmission line from local to overall, enabling the fault detection method to better cope with the uncertainty of complex lines and improving the accuracy and timeliness of fault judgment. For example, when the voltage drops suddenly or the current increases suddenly at a certain measuring point, combined with the parameter changes of adjacent measuring points, the nature and scope of the fault can be judged more accurately. And by comprehensively analyzing the measuring point operating parameters, the reliability of the traveling wave signal can be verified using the variation law of electrical quantities. For example, if the traveling wave signal indicates that there is a fault in a certain section of the line, but the measuring point operating parameters of this section of the line do not show abnormalities, it can be judged that the traveling wave signal is misjudged, thus avoiding incorrect fault location.

[0055] As an alternative embodiment, determining the target fault state index corresponding to the target transmission line according to the power parameter fluctuation index and the initial fault state index includes: determining the fault position corresponding to the target transmission line; determining the voltage fluctuation index corresponding to the fault position according to the power parameter fluctuation index; and determining the target fault state index corresponding to the fault position according to the voltage fluctuation index and the initial fault state index.

[0056] In this embodiment, the specific steps for determining the target fault state index corresponding to the target transmission line based on the power parameter fluctuation index and the initial fault state index are described.

[0057] Among them, the fault location is involved, and the fault location is the fault location in the target transmission line preliminarily determined by the traveling wave parameters.

[0058] Among them, the voltage fluctuation index is involved. The voltage fluctuation index is an index used to quantify voltage fluctuations (such as amplitude changes). For example, the voltage fluctuation index can be the differential value of the voltage (i.e., the voltage change rate), which is used to measure the change speed of the voltage over time. When a fault occurs, the voltage may suddenly drop or rise, resulting in the voltage change rate exceeding the normal operating range, thereby forming a relatively high voltage fluctuation index, which can reflect the abnormal fluctuation characteristics of the power parameters during a fault.

[0059] In the steps involved in this embodiment, first, the fault location corresponding to the target transmission line is determined. Then, according to the power parameter fluctuation index, the voltage fluctuation index corresponding to the fault location is determined. Finally, according to the voltage fluctuation index and the initial fault state index, the target fault state index corresponding to the fault location is determined.

[0060] The initial fault state index preliminarily determines the fault location based on the traveling wave parameters. However, the traveling wave signal may be interfered by various factors in a complex line. By introducing the voltage fluctuation index and making a comprehensive judgment in combination with the initial fault state index, the misjudgment or missed judgment caused by a single traveling wave signal can be effectively reduced. For example, when the traveling wave signal indicates that there is a fault at a certain location, but the voltage fluctuation index does not exceed the threshold, it can be judged as a misjudgment of the traveling wave signal, thereby avoiding incorrect fault location. Therefore, by combining the voltage fluctuation index and the initial fault state index, the fault state of the target transmission line can be more comprehensively reflected, and the problem of inaccurate determination of the fault state caused by the complexity of the line in the traveling wave protection method can be effectively solved.

[0061] As an alternative embodiment, determining the fault location corresponding to the target transmission line includes: when the traveling wave parameters include the speed parameter and the arrival time parameters corresponding to multiple detection points respectively, determining the fault direction according to the arrival time parameters corresponding to the multiple detection points respectively, where the corresponding arrival time parameter is used to represent the time when the traveling wave is detected by the corresponding detection point, and the speed parameter is used to represent the propagation speed of the traveling wave; determining the fault distance according to the arrival time parameters corresponding to the multiple detection points respectively and the speed parameter; and determining the fault location corresponding to the target transmission line according to the fault direction and the fault distance.

[0062] In this embodiment, the specific steps for determining the fault location corresponding to the target transmission line are described.

[0063] Among them, a speed parameter is involved, and this speed parameter represents the propagation speed of the traveling wave in the transmission line. The propagation speed of the traveling wave is affected by the electrical characteristics of the line (such as wave impedance, distributed parameters, etc.).

[0064] Among them, an arrival time parameter is involved, and this arrival time parameter represents the time when the traveling wave arrives at the detection point. For example, a fault occurs at a certain position in the target transmission line, and the fault point generates traveling wave signals, and these signals propagate along the line to the detection point. The detection point records the time when the traveling wave arrives, that is, the arrival time parameter.

[0065] Among them, a fault direction is involved, and this fault direction is the position direction of the fault point relative to the detection point. By analyzing the time difference of the traveling wave arriving at different detection points, it can be judged whether the fault point is upstream or downstream of the detection point. For example, if the traveling wave arrives at the head end of the line first and then at the tail end, the fault point may be between the head end of the line and the fault point.

[0066] Among them, a fault distance is involved, and this fault distance is the distance between the fault point and the detection point.

[0067] In the steps involved in this embodiment, when the traveling wave parameters include the speed parameter and the arrival time parameters respectively corresponding to multiple detection points, first, according to the arrival time parameters respectively corresponding to multiple detection points, the fault direction is determined. Then, according to the arrival time parameters respectively corresponding to multiple detection points and the speed parameter, the fault distance is determined. Finally, according to the fault direction and the fault distance, the fault position corresponding to the target transmission line is determined.

[0068] The determination of the fault direction can provide a directional guidance for fault location. And the determination of the fault distance further quantifies the specific distance between the fault point and the detection point. By comprehensively analyzing the fault direction and the fault distance, it helps to accurately determine the fault position, thereby helping to improve the accurate judgment of the fault state of the target transmission line.

[0069] As an optional embodiment, determining the fault direction according to the arrival time parameters respectively corresponding to multiple detection points includes: determining the arrival order parameters respectively corresponding to multiple arrival time parameters according to the arrival time parameters respectively corresponding to multiple detection points; determining the fault direction according to the arrival order parameters respectively corresponding to multiple arrival time parameters.

[0070] In this embodiment, the specific steps of determining the fault direction according to the arrival time parameters respectively corresponding to multiple detection points are described.

[0071] Among them, the arrival position parameter is involved. The arrival position parameter refers to the order in which the traveling wave signal arrives at each detection point, and this arrival position parameter can reflect the propagation path of the traveling wave in the transmission line.

[0072] In the steps involved in this embodiment, first, according to the arrival time parameters corresponding to multiple detection points, the arrival position parameters corresponding to the multiple arrival time parameters are determined respectively. Then, according to the arrival position parameters corresponding to the multiple arrival time parameters, the fault direction is determined.

[0073] By analyzing the arrival time parameters of multiple detection points, the arrival order of the traveling wave signal can be clarified, and thus the propagation path of the traveling wave in the transmission line can be intuitively reflected, which helps to accurately determine the relative fault direction between the fault point and the detection point. The fault direction can quickly narrow the analysis range of the fault location, reduce unnecessary detections and analyses, and improve the efficiency of fault state analysis.

[0074] As an alternative embodiment, determining the target fault state index corresponding to the fault location based on the voltage fluctuation index and the initial fault state index includes: determining the to-be-verified fault state index corresponding to the target transmission line based on the voltage fluctuation index and the initial fault state index; determining the current fluctuation index corresponding to the fault location based on the power parameter fluctuation index; and determining the target fault state index corresponding to the fault location based on the current fluctuation index and the to-be-verified fault state index.

[0075] In this embodiment, the specific steps of determining the target fault state index corresponding to the fault location based on the voltage fluctuation index and the initial fault state index are described.

[0076] Among them, the to-be-verified fault state index is involved. The to-be-verified fault state index is an index reflecting the fault state of the target transmission line, but this to-be-verified fault state index is an index that needs to be verified again after being initially combined with the voltage fluctuation index and the initial fault state index.

[0077] Among them, the current fluctuation index is involved. The current fluctuation index is an index quantifying the current fluctuation state (such as the change amplitude). The current fluctuation index can be based on the instantaneous change of the current before and after detecting a specific time point or a specific fault state occurs.

[0078] In the steps involved in this embodiment, first, according to the voltage fluctuation index and the initial fault state index, the to-be-verified fault state index corresponding to the target transmission line is determined. Then, according to the power parameter fluctuation index, the current fluctuation index corresponding to the fault location is determined. Finally, according to the current fluctuation index and the to-be-verified fault state index, the target fault state index corresponding to the fault location is determined.

[0079] The fault state to be verified includes a preliminary judgment based on voltage changes and initial fault state information obtained from traveling wave signals, providing a basis for subsequent in-depth analysis of fault state assessment. By combining the voltage fluctuation index, the initial fault state index, and the current fluctuation index, the fault state can be comprehensively evaluated from multiple perspectives (such as voltage and current changes), improving the comprehensiveness of fault state analysis. Therefore, through comprehensive analysis of the voltage fluctuation index, the initial fault state index, and the current fluctuation index, it helps to reduce the uncertainty and error in fault diagnosis when facing complex line structures, improving the reliability and accuracy of fault state determination.

[0080] As an alternative embodiment, determining the operating parameters corresponding to the target transmission line includes: determining the partition parameters of the target transmission line, where the partition parameters are used to represent the partition of the power system where the target transmission line is located; based on the partition parameters and the target transmission line, determining the line characteristics corresponding to the target transmission line; and based on the line characteristics, determining the operating parameters corresponding to the target transmission line.

[0081] In this embodiment, the specific steps for determining the operating parameters corresponding to the target transmission line are described.

[0082] Among them, partition parameters are involved. The partition parameters are specific protection areas or operating areas where the target transmission line is located in the power system. The partition parameters can reflect the location and functional characteristics of the target transmission line in the power system. For example, the partition parameters can be "DC line protection area", "converter station protection area", "DC transformer protection area", etc.

[0083] Among them, line characteristics are involved. The line characteristics are characteristics related to the electrical and physical characteristics of the target transmission line, including information such as the length, material, resistance, capacitance, inductance, and structural layout of the line, as well as the change characteristics of electrical parameters such as voltage and current under normal operation and specific fault states of the line.

[0084] In the steps involved in this embodiment, first, the partition parameters of the target transmission line are determined. Then, based on the partition parameters and the target transmission line, the line characteristics corresponding to the target transmission line are determined. Finally, based on the line characteristics, the operating parameters corresponding to the target transmission line are determined.

[0085] By determining the partition parameters of the target transmission line, it helps to clarify the line characteristics of the transmission line, so as to take targeted fault state analysis measures. By determining the line characteristics, it can provide an analysis basis for the determination of operating parameters and fault states, thus helping to improve the accuracy of fault detection and state judgment, and reducing the risk of false alarms or missed alarms caused by line complexity.

[0086] Based on the above embodiments and optional embodiments, an optional implementation manner is provided, which will be specifically described below.

[0087] In the related art, in a transmission line, when using a traveling wave protection method to determine the fault state of the transmission line, due to the complexity of the transmission line, such as the line length, branch structure, and environmental factors along the line, etc., the traveling wave signal is easily interfered during the transmission process, resulting in the technical problem of inaccurate determination of the fault state of the transmission line.

[0088] In response to the above problems, no effective solution has been proposed yet.

[0089] In view of this, in an optional implementation manner of the present invention, a method for determining a fault state index of a transmission line is provided, which can also be referred to as a protection method for a flexible DC distribution network system, and it can effectively solve the technical problem of inaccurate determination of the fault state of the transmission line when using the traveling wave protection method due to the complexity of the transmission line.

[0090] Figure 2 It is a schematic diagram of zone protection in an optional implementation manner of the present invention. Figure 3 It is a schematic diagram of measuring points in the protection area of a DC transformer in an optional implementation manner of the present invention. As Figure 2 、 Figure 3 shown, the following will be described in detail.

[0091] S1. Receive a target index determination instruction, where the target index determination instruction is an instruction for determining the fault state of a target transmission line;

[0092] S2. In response to the target index determination instruction, determine the operating parameters corresponding to the target transmission line, where the operating parameters include traveling wave parameters;

[0093] Specifically, S2 includes:

[0094] S21. Determine the partition parameters of the target transmission line, where the partition parameters are used to represent the partition of the power system where the target transmission line is located;

[0095] For example, taking a multi-terminal interconnected distribution network in a certain place as an example, according to the principle of protection area division (the same as the above partition parameters) and the protected objects in the system, the division of the protection area of this multi-port system is as Figure 2As shown in the figure. The entire system is divided into three categories: DC transformer protection area, DC line protection area, and converter protection area (including the connecting transformer area), with a total of six sub-areas (the same as the above sub-area parameters). For example, the DC line protection area is the DC transmission line area, and the equipment to be protected is the DC cable. The DC transformer (DCT) protection area is the area between the DC busbar on the high-voltage side and the DC busbar on the low-voltage side of the DC. The equipment to be protected is the DCT, which mainly includes intermediate-frequency transformers, semiconductor switching devices, etc.

[0096] In each protection sub-area, different protections are configured according to the different performance parameters and external characteristics of the equipment in the sub-area.

[0097] For example, the DC line protection function is divided into the following categories:

[0098] 1) Traveling wave type: Traveling wave protection;

[0099] 2) Current type: Overcurrent protection;

[0100] 3) Voltage type: Voltage unbalance protection, overvoltage protection, undervoltage protection;

[0101] 4) Differential type: Line differential protection;

[0102] S22, according to the sub-area parameters and the target transmission line, determine the line characteristics corresponding to the target transmission line;

[0103] S23, determine the position parameters of multiple measuring points corresponding to the target transmission line;

[0104] For example, by real-time monitoring signals such as voltage and current at the measuring points, Figure 3 As shown in the figure are the measuring points of the DC transformer (the same as the above measuring point position parameters); the measuring points of the DC line are the single-pole-to-ground voltage, inter-pole voltage, and busbar current of the line. The above monitoring signals are transmitted to the system control and protection module, and the control and protection module calculates the voltage and current value signals according to the criteria to determine whether a fault occurs. If the detected signal value is abnormal, the criticality level is judged (the same as the above fault state index), and the next instruction is sent to the local layer. The criteria and instructions will vary according to the actual engineering situation.

[0105] S24, according to the line characteristics and the position parameters of multiple measuring points, determine the operating parameters of the measuring points corresponding to the position parameters of multiple measuring points respectively;

[0106] S25, according to the operating parameters of the measuring points corresponding to the position parameters of multiple measuring points respectively, determine the operating parameters corresponding to the target transmission line.

[0107] S3, according to the traveling wave parameters, determine the initial fault state index corresponding to the target transmission line;

[0108] For example, the DC line protection function may include traveling wave types, i.e., traveling wave protection (same as the above-mentioned traveling wave parameters).

[0109] S4. Determine the power parameter fluctuation index corresponding to the target transmission line according to the operating parameters;

[0110] S5. Determine the target fault state index corresponding to the target transmission line according to the power parameter fluctuation index and the initial fault state index.

[0111] Specifically, S5 includes:

[0112] S51. When the traveling wave parameters include the speed parameter and the arrival time parameters corresponding to multiple detection points respectively, determine the arrival rank parameters corresponding to the multiple arrival time parameters according to the arrival time parameters corresponding to the multiple detection points respectively, where the corresponding arrival time parameter is used to represent the time when the traveling wave is detected by the corresponding detection point, and the speed parameter is used to represent the propagation speed of the traveling wave;

[0113] S52. Determine the fault direction according to the arrival rank parameters corresponding to the multiple arrival time parameters respectively.

[0114] S53. Determine the fault distance according to the arrival time parameters corresponding to the multiple detection points respectively and the speed parameter; determine the fault location corresponding to the target transmission line according to the fault direction and the fault distance;

[0115] For example, due to the small damping of flexible DC transmission, a large amount of current will quickly enter the fault point when a fault occurs. Therefore, there are high requirements for the quick operation of the protection. The traveling wave protection has a fast operation speed, can cut off the line fault before the converter station is blocked, and can identify the fault distance (same as the above-mentioned fault distance). Judging based on the transient current correlation coefficient meets the selectivity requirements of the multi-terminal system and is more reliable. The traveling wave distance protection uses the traveling wave after the transmission line fails, making the protection device have the characteristic of ultra-high-speed operation; and by using the characteristics of traveling wave reflection and refraction, the fault distance can be accurately calculated, and at the same time, it can be used as both the protection action discrimination quantity and the ranging output result, that is, integrating protection and ranging, effectively solving the problem of unable to accurately and quickly locate the fault (same as the above-mentioned fault location).

[0116] S54. Determine the voltage fluctuation index corresponding to the fault location according to the power parameter fluctuation index;

[0117] S55. Determine the to-be-verified fault state index corresponding to the target transmission line according to the voltage fluctuation index and the initial fault state index;

[0118] S56. Determine the current fluctuation index corresponding to the fault location according to the power parameter fluctuation index;

[0119] S57, determining a target fault state index corresponding to the fault location according to the current fluctuation index and the fault state index to be verified.

[0120] For example, since there are many DC access points in multi-terminal systems, the traveling wave protection as a single-terminal protection is difficult to distinguish the faults at the end of the upper line and the outlet of the lower line, and there is a risk of overstepping misoperation or refusal to operate at this level. Therefore, it is often combined with other protection schemes. Among them:

[0121] Low voltage protection can be used as a coordinated protection scheme. When the voltage differential (same as the voltage fluctuation index mentioned above) is greater than a certain fixed value and the voltage value is less than the fixed value within a certain time window, it is judged as a low voltage in the DC system caused by a line fault or the AC system.

[0122] DC voltage unbalance protection is also used to protect against single-pole grounding faults. It mainly detects the upper and lower bridge arm voltages on the valve side of the bridge arm reactor and compares them with the protection setting (the same as the above-mentioned voltage fluctuation index).

[0123] Overcurrent protection is mainly used to protect against double-click short-circuit faults, which is determined by detecting the positive and negative voltage / current values ​​of the system; overvoltage protection is mainly used to protect against overvoltage caused by control abnormalities, accumulation, single-pole grounding, open-level line, etc., which is determined by detecting the positive and negative voltages.

[0124] The protection device for DC transformer protection is located in the protection area of ​​the DC transformer and is closely integrated with the control device of the DCT. Its protection function includes differential protection (same as the above current fluctuation index). Its functions and measurement points are as shown in the attached Figure 3 As shown, I dc1P ,I dc1N ,I dc2P ,I dc2N are the positive and negative DC currents on both sides of DCT, U dc1P , U dc1N , U dc2P , U dc2N They are the positive and negative DC voltages on both sides of the DCT respectively.

[0125] At the same time, longitudinal differential protection (same as the above current fluctuation index) can be used as a backup protection for traditional DC lines. Longitudinal differential protection is formed by detecting the polarity or magnitude of the current at both ends. It is not affected by excessive resistance and can be used as a backup to the main protection to detect high-resistance grounding faults where the sensitivity of the line main protection is not enough.

[0126] Differential protection (same as the above current fluctuation index) is mainly used to protect the pole-to-pole faults and single-pole grounding faults occurring on the DC transformer, which is achieved by detecting the current on the medium and low voltage sides of the positive pole. It is divided into three sections: Section I alarm section: alarm; Section II low-setting action section: delay in tripping the DC circuit breaker of the DC transformer; Section III high-setting action section: immediately trip the DC circuit breaker of the DC transformer.

[0127] Among them, the reference value of the protection setting value is determined by the system parameters, and the setting value is a multiple of the reference value. Usually, the initial setting value is selected from conventional empirical values. For example, the setting value needs to avoid the disturbances that may be encountered during system operation or other ripple levels caused by the equipment of the system itself. During the subsequent project commissioning and testing stage, it can be adjusted and determined according to the usage situation.

[0128] Through the above steps, a sectional protection method based on a flexible interconnected system is proposed. The different positions and characteristics of various equipment in the distribution network are studied and classified into sections, and further protection configurations and protection principles are proposed. Taking the distribution network in a certain area as an example, the specific implementation method is as follows:

[0129] A1. DC bus and DC line area:

[0130] Table 1 is a schematic table of traveling wave protection, as shown in Table 1.

[0131] Table 1

[0132]

[0133] Table 2 is a schematic table of DC voltage unbalance protection, as shown in Table 2.

[0134] Table 2

[0135]

[0136]

[0137] Table 3 is a schematic table of DC line differential protection, as shown in Table 3.

[0138] Table 3

[0139]

[0140]

[0141] Table 4 is a schematic table of DC bus differential protection, as shown in Table 4.

[0142] Table 4

[0143]

[0144]

[0145] Table 5 is a schematic table of DC low-voltage over-current protection, as shown in Table 5.

[0146] Table 5

[0147]

[0148] Table 6 is a schematic table of DC over-voltage protection, as shown in Table 6.

[0149] Table 6

[0150]

[0151]

[0152] Table 7 is a schematic table of DC low-voltage protection, as shown in Table 7.

[0153] Table 7

[0154]

[0155] Table 8 is a schematic table of DC over-current protection, as shown in Table 8.

[0156] Table 8

[0157]

[0158]

[0159] A2. DC transformer area:

[0160] Table 9 is a schematic table of DC transformer differential protection, as shown in Table 9.

[0161] Table 9

[0162]

[0163]

[0164] Through the above optional implementation manners, at least the following beneficial effects can be achieved:

[0165] (1) Compared with the related art, by combining the power parameter fluctuation index and the traveling wave parameter, the present invention can analyze the line state when a fault occurs more comprehensively, thereby avoiding misjudgment or missed judgment that may be caused by a single detection method. And by introducing the power parameter fluctuation index, the nature and location of the fault can be further verified, the reliability of fault judgment can be improved, and thus the technical problem that the fault state of the transmission line cannot be accurately determined due to the complexity of the transmission line when using the traveling wave protection method to determine the fault state of the transmission line is solved.

[0166] (2) Compared with the related art, by setting the measuring point position parameters at the key points of the transmission line, the present invention can more precisely capture the local changes when a fault occurs, avoid misjudgment of the fault state caused by the overall complexity of the line, and then combine the operating parameters of multiple measuring points to comprehensively reflect the operating state of the transmission line from local to overall, enabling the fault detection method to better cope with the uncertainty of complex lines and improving the accuracy and timeliness of fault judgment.

[0167] (3) Compared with the related art, by analyzing the arrival time parameters of multiple detection points, the present invention can clarify the arrival order of the traveling wave signals, and then can intuitively reflect the propagation path of the traveling wave in the transmission line, which helps to accurately determine the relative fault direction between the fault point and the detection point, and further helps to quickly narrow the analysis scope of the fault location, reduce unnecessary detections and analyses, and improve the efficiency of fault state analysis.

[0168] (4) Compared with the related art, by combining the voltage fluctuation index, the initial fault state index and the current fluctuation index, the present invention can comprehensively evaluate the fault state from multiple angles, improve the comprehensiveness of fault state analysis, which helps to reduce the uncertainty and error in fault diagnosis when facing a complex line structure, and improve the reliability and accuracy of fault state determination.

[0169] (5) Compared with the related art, by determining the partition parameters of the target transmission line, the present invention helps to clarify the line characteristics of the transmission line, so as to take targeted fault state analysis measures, which can provide an analysis basis for the determination of operating parameters and the determination of fault states, and further helps to improve the accuracy of fault detection and state judgment, and reduce the risk of false alarms or missed alarms caused by line complexity.

[0170] It should be noted that for the foregoing method embodiments, for the sake of simple description, they are all expressed as a series of action combinations. However, those skilled in the art should know that the present invention is not limited by the described action sequence, because according to the present invention, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0171] Through the description of the above embodiments, those skilled in the art can clearly understand that the method according to the above embodiments can be implemented by means of software plus a necessary general hardware platform. Of course, it 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, in essence, or the part that contributes to the prior art can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes several instructions for causing a terminal device (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods of the various embodiments of the present invention.

[0172] Embodiment 2

[0173] According to an embodiment of the present invention, there is also provided a device for implementing the above-mentioned method for determining the fault state index of a transmission line. Figure 4 It is a structural block diagram of the device for determining the fault state index of a transmission line according to an embodiment of the present invention, as Figure 4 shown. The device includes: a receiving module 402, a response module 404, a first determination module 406, a second determination module 408, and a third determination module 410. The device will be described in detail below.

[0174] The receiving module 402 is configured to receive a target index determination instruction, where the target index determination instruction is an instruction for determining the fault state of a target transmission line; the response module 404 is connected to the above-mentioned receiving module 402 and is configured to respond to the target index determination instruction to determine the operating parameters corresponding to the target transmission line, where the operating parameters include traveling wave parameters; the first determination module 406 is connected to the above-mentioned response module 404 and is configured to determine an initial fault state index corresponding to the target transmission line according to the traveling wave parameters; the second determination module 408 is connected to the above-mentioned first determination module 406 and is configured to determine a power parameter fluctuation index corresponding to the target transmission line according to the operating parameters; the third determination module 410 is connected to the above-mentioned second determination module 408 and is configured to determine a target fault state index corresponding to the target transmission line according to the power parameter fluctuation index and the initial fault state index.

[0175] It should be noted here that the above-mentioned receiving module 402, response module 404, first determination module 406, second determination module 408, and third determination module 410 correspond to steps S102 to S110 in the method for determining the fault state index of a transmission line. The examples and application scenarios implemented by the multiple modules and the corresponding steps are the same, but are not limited to the content disclosed in the above-mentioned Embodiment 1.

[0176] Embodiment 3

[0177] According to another aspect of the embodiments of the present invention, there is also provided an electronic device, including: a processor; a memory for storing instructions executable by the processor, wherein the processor is configured to execute the instructions to implement the transmission line fault state index determination method according to any one of the above.

[0178] Embodiment 4

[0179] According to another aspect of the embodiments of the present invention, there is also provided a computer-readable storage medium. When the instructions in the computer-readable storage medium are executed by the processor of the electronic device, the electronic device can execute the transmission line fault state index determination method according to any one of the above.

[0180] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0181] In the above embodiments of the present invention, the descriptions of the respective embodiments have their own emphases. For the parts not detailed in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0182] In several embodiments provided in the present application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only illustrative. For example, the division of the units can be a logical function division. In actual implementation, there can be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces. The indirect couplings or communication connections of the units or modules can be in an electrical or other form.

[0183] The units described as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place, or can be distributed to multiple units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0184] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above integrated units can be implemented in the form of hardware or in the form of software functional units.

[0185] When the integrated unit is implemented in the form of 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 the present invention, 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. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes: various media such as USB flash drives, read-only memories (ROMs), random access memories (RAMs), mobile hard disks, magnetic disks, or optical discs that can store program codes.

[0186] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for determining a transmission line fault state index, characterized in that: include: receiving a target index determination instruction, wherein the target index determination instruction is an instruction for determining a fault state of a target power transmission line; In response to the target index determination instruction, determining an operating parameter corresponding to the target transmission line, wherein the operating parameter includes a traveling wave parameter; Determining an initial fault state index corresponding to the target transmission line according to the traveling wave parameter; Determining, based on the operating parameters, a power parameter fluctuation index corresponding to the target power transmission line; A target fault state index corresponding to the target power transmission line is determined according to the power parameter fluctuation index and the initial fault state index.

2. The method according to claim 1, characterized in that The determining of the operating parameters corresponding to the target transmission line includes: Determining location parameters of a plurality of measuring points corresponding to the target transmission line; Determining, based on the plurality of measuring point position parameters, measuring point operation parameters respectively corresponding to the plurality of measuring point position parameters; The operating parameters corresponding to the target power transmission line are determined according to the measuring point operating parameters respectively corresponding to the plurality of measuring point position parameters.

3. The method according to claim 1, characterized in that The step of determining a target fault state index corresponding to the target power transmission line according to the power parameter fluctuation index and the initial fault state index includes: determining a fault location corresponding to the target transmission line; Determining a voltage fluctuation index corresponding to the fault location according to the power parameter fluctuation index; A target fault state index corresponding to the fault location is determined according to the voltage fluctuation index and the initial fault state index.

4. The method according to claim 3, characterized in that: The determining of the fault location corresponding to the target transmission line comprises: In the case where the traveling wave parameters include a speed parameter and arrival time parameters corresponding to a plurality of detection points, the fault direction is determined according to the arrival time parameters corresponding to the plurality of detection points, wherein the corresponding arrival time parameter is used to indicate the time when the corresponding detection point detects the traveling wave, and the speed parameter is used to indicate the propagation speed of the traveling wave; Determining the fault distance according to the arrival time parameters respectively corresponding to the plurality of detection points and the speed parameter; A fault location corresponding to the target transmission line is determined according to the fault direction and the fault distance.

5. The method according to claim 4, characterized in that The determining the fault direction according to the arrival time parameters respectively corresponding to the plurality of detection points includes: Determine the arrival order parameters corresponding to the plurality of arrival time parameters respectively according to the arrival time parameters respectively corresponding to the plurality of detection points; The fault direction is determined according to the arrival order parameters respectively corresponding to the multiple arrival time parameters.

6. The method according to claim 3, characterized in that The step of determining a target fault state index corresponding to the fault location based on the voltage fluctuation index and the initial fault state index includes: Determining a to-be-verified fault state index corresponding to the target transmission line according to the voltage fluctuation index and the initial fault state index; Determining a current fluctuation index corresponding to the fault location according to the power parameter fluctuation index; A target fault state index corresponding to the fault location is determined according to the current fluctuation index and the fault state index to be verified.

7. The method according to any one of claims 1 to 6, characterized in that: The determining of the operating parameters corresponding to the target transmission line includes: Determine a partition parameter of a target transmission line, wherein the partition parameter is used to represent a partition of a power system in which the target transmission line is located; Determining, based on the partition parameters and the target power transmission line, a line feature corresponding to the target power transmission line; Based on the line characteristics, operating parameters corresponding to the target transmission line are determined.

8. A device for determining a fault state index of a power transmission line, characterized in that: include: A receiving module, configured to receive a target index determination instruction, wherein the target index determination instruction is an instruction for determining a fault state of a target power transmission line; a response module, configured to determine, in response to the target index determination instruction, an operating parameter corresponding to the target transmission line, wherein the operating parameter includes a traveling wave parameter; A first determination module, configured to determine an initial fault state index corresponding to the target transmission line according to the traveling wave parameter; A second determination module, configured to determine a power parameter fluctuation index corresponding to the target power transmission line according to the operating parameters; The third determination module is used to determine a target fault state index corresponding to the target transmission line according to the power parameter fluctuation index and the initial fault state index.

9. An electronic device, characterized in that: include: processor; a memory for storing instructions executable by the processor; The processor is configured to execute the instructions to implement the method for determining a power transmission line fault state index according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: When the instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device is enabled to execute the method for determining a power transmission line fault state index according to any one of claims 1 to 7.

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