Power transmission and distribution network line fault automatic line selection and positioning method

Abstract

The application relates to a power transmission and distribution network line fault automatic line selection and positioning method. The method can realize automatic identification, line selection and accurate positioning of faults in the power transmission and distribution network line, and is especially suitable for complex distribution networks with T-connection branch line structures. In view of the problems such as device phase sequence error and opposite polarity that may occur in the line, an interval identification and line selection strategy based on current correlation coefficient determination is provided. By dividing the triggering device into four sections, the correlation coefficient between the fault currents is calculated, and the threshold setting and the correlation coefficient sorting are combined to realize automatic judgment of the fault interval and accurate selection of the fault positioning line, and finally the positioning of the fault point is completed. The method has the advantages of high automation degree, wide application range and high positioning accuracy, and can significantly improve the fault handling efficiency and operation reliability of the power transmission and distribution network.

Description

Technical Field

[0001] This invention belongs to the field of line fault identification technology, and in particular relates to an automatic line selection and location method for power transmission and distribution network line faults. Background Technology

[0002] Transmission and distribution power lines are widely distributed in diverse environments such as cities, rural areas, and mountainous regions. Their operating conditions are complex and variable, making them susceptible to faults caused by factors such as tree obstructions, animal short circuits, and external damage. Furthermore, transmission and distribution power lines are characterized by their wide coverage, complex network structure, and numerous branch nodes (especially a high proportion of T-connected lines, with multiple levels of T-connections). This makes traditional manual line inspection methods time-consuming and inefficient. Moreover, the need to process large amounts of line and equipment information makes it difficult to quickly pinpoint the location of faulty sections.

[0003] In existing technologies, while traveling wave-based dual-end positioning technology has been applied to fault location, it still relies on manual judgment of the faulty section and selection of a specific traveling wave for positioning. Due to differences in worker experience, not only does the judgment process take varying amounts of time, but for the same fault, different personnel may select different traveling waves for positioning, directly leading to a decrease in positioning accuracy. Furthermore, current fault line selection methods are already relatively limited; when there are many devices on the line, it is difficult to effectively eliminate lines and devices irrelevant to positioning, which can interfere with the positioning process.

[0004] like Figure 1 As shown, when a T-connection line fault occurs, the possible fault locations are indicated by the six relative positions marked by the red arrows (the actual distance is subject to actual measurement). The green arrow in the figure indicates the current direction, the installation direction of the triggering device is consistent with the current direction, and the orange dot marks the T-connection.

[0005] First triggering device:

[0006] When a fault occurs at positions 1, 2, 3, or 5, triggering device 1 may be the first to trigger; when a fault occurs at positions 2, 3, 4, or 5, triggering device 2 may be the first to trigger; when a fault occurs at positions 2, 3, 5, or 6, triggering device 3 may be the first to trigger.

[0007] Trigger device selection:

[0008] When the fault occurs at position 1, you can choose to trigger devices 1 and 2 or trigger devices 1 and 3 for location;

[0009] When the fault occurs at position 2, you can choose to trigger devices 1 and 2 or trigger devices 1 and 3 for location;

[0010] When the fault occurs at position 3, you can choose to trigger devices 1 and 2 or trigger devices 2 and 3 for location;

[0011] When the fault occurs at position 4, you can choose to trigger devices 1 and 2 or trigger devices 2 and 3 for location;

[0012] When the fault occurs at position 5, you can choose to trigger devices 1 and 3 or trigger devices 2 and 3 for location;

[0013] When the fault occurs at position 6, you can choose to trigger devices 1 and 3 or trigger devices 2 and 3 for location.

[0014] In particular, due to the special topology of T-connected lines (including multi-level T-connected lines), when the power supply side is fixed, the process of determining the location, selecting the line, and locating the fault will be more complicated and significantly more difficult when the fault occurs near the T-connection. Summary of the Invention

[0015] The purpose of this invention is to solve the problems existing in the prior art and provide an automatic fault selection and location method for power transmission and distribution network lines, especially capable of automatic fault selection and location in complex power distribution networks with T-junction branch structures.

[0016] This invention provides a method for automatic fault selection and location in power transmission and distribution networks, comprising the following steps:

[0017] Includes the following steps:

[0018] Determine the time when the fault current first arrives at each triggering device on the line, and designate the location of the triggering device that arrives earliest as the first point in the entire line; wherein, the triggering devices installed on each phase of the three-phase line constitute the points on that phase line.

[0019] Based on the determined first point, the points on the line are first grouped into upstream and downstream sections; then, based on the first point, the points on the line are grouped into four segments. The upstream section includes all points from the first point towards the power supply side; the downstream section includes all other points on the line excluding the upstream section; the first segment includes the points in the upstream section through which the current flows from the power supply side to the first point; the second segment includes the points in the upstream section excluding the first segment; the third segment includes the points in the downstream section through which the current flows after passing the first point; and the fourth segment includes the points in the downstream section excluding the third segment.

[0020] Acquire fault current waveform data recorded by triggering devices at various points on the power transmission and distribution network lines;

[0021] For the triggering device at the first point, calculate the pair of currents between each of its three phases (A, B, and C) triggering devices and any other triggering device at any other point (A, B, and C). The phase correlation index is used to determine whether the pair of currents are in phase, and the location correlation index is used to determine the fault interval.

[0022] Based on the current amplitude of all triggering devices at the triggering moment, the faulty phase is identified;

[0023] Based on the phase correlation index, location point correlation index, and preset interval fault judgment conditions and out-of-area fault judgment conditions, combined with the identified fault phase, an interval unsorted correlation pair array or an out-of-area unsorted correlation pair array for fault location is selected.

[0024] When there is an array of interval correlation pairs to be sorted, a pair of target correlation pairs is selected from the array of interval correlation pairs to be sorted according to the first preset rule, and the two triggering devices corresponding to the pair of target correlation pairs perform interval double-end traveling wave positioning.

[0025] When there is only an array of out-of-area unsorted correlation pairs, a pair of target correlation pairs is selected from the array of out-of-area unsorted correlation pairs according to the second preset rule. Out-of-area double-ended traveling wave positioning is performed on the two triggering devices corresponding to the pair of target correlation pairs. Based on the positioning result, it is determined that the fault point is located in the outer area of ​​the triggering device that is closer to it.

[0026] Because locating a fault in a T-connected line requires determining whether it occurs on the main line or the T-connector, relying solely on location analysis can lead to errors due to span (the actual distance between adjacent towers) and wave velocity (which depends on the line material; bare conductors or cables, and the wave velocity is difficult to determine in complex distribution networks). This application first divides the triggering devices into four sections, then calculates the correlation coefficient of the current pairs between each triggering device, and finally combines threshold settings and correlation coefficient sorting to achieve automatic fault zone identification and precise selection of the fault location line, ultimately locating the fault point. Especially for T-connected line location, it is unnecessary to first determine whether the fault occurs on the main line or the T-connector; correlation analysis alone is sufficient for fault location and line selection.

[0027] In actual power transmission and distribution network scenarios, the triggering devices in the line may encounter problems such as incorrect phase sequence and reverse polarity during installation, for example... Figure 2As shown, the phase sequence of trigger devices 2A and 2B at point 2 is incorrect, and the polarity of the trigger device at point 3 is reversed. These installation problems in real-world scenarios can lead to errors in the final fault location. This application first divides the trigger devices into four sections, then calculates the correlation coefficient of the current pairs between each trigger device at the first point and each trigger device in other sections. Combined with fault phase judgment, threshold setting, and correlation coefficient sorting, automatic fault interval judgment and accurate selection of fault location devices can be achieved, ultimately locating the fault point. This application can solve these installation problems in real-world scenarios by using correlation calculation and threshold filtering to handle equipment installation issues, correctly select lines, and complete the final location.

[0028] Preferably, the method for calculating the correlation index and the location point correlation index includes:

[0029] The phase correlation index is calculated based on the current waveform data of the corresponding pair of currents between the two and four cycles before the fault occurs.

[0030] The location point correlation index is calculated based on the current waveform data points of the corresponding pair of currents 10 times after the fault occurs.

[0031] The two key judgments—whether they belong to the same physical phase and whether they are located on opposite sides of the fault point—are decoupled and precisely quantified. Pre-fault steady-state data ensures the reliability of phase determination, while post-fault initial traveling wave data ensures the accuracy of location determination. The two indicators have clear physical meanings and are calculated independently, laying a solid foundation for subsequent judgments based on combined conditions.

[0032] Preferably, the method for identifying the faulty phase based on the current amplitude of all triggering devices at the triggering time includes:

[0033] Compare the current amplitude at the triggering time of all triggering devices, and take the maximum value as the maximum current value. If the current value at the triggering time of any triggering device is greater than or equal to 80% of the maximum current value, then the phase where the triggering device is located is the faulty phase.

[0034] As a step before screening, this step can quickly eliminate most invalid ij combinations (such as current pairs between non-faulty phases), greatly reducing the computational workload of phase correlation and location correlation. Using an 80% dynamic relative threshold instead of a fixed value, it can adapt to different fault intensities and system operating modes, balancing the sensitivity and accuracy of screening, ensuring that no phase with strong fault characteristics is missed.

[0035] Preferably, the method for selecting the inter-regional unordered correlation pairs array or the inter-regional unordered correlation pairs array for fault location includes:

[0036] Define the correlation index as cur_p1 ij 1-mn The correlation index for location points is cur_p2 ij 1-mn Where i represents three phases, i = A, B, C; j represents three phases, j = A, B, C; m represents a segment, m = 1, 2, 3, 4; n represents the nth point in the segment, n = 1, 2, ..., N;

[0037] Define the following four conditions:

[0038] Condition 1: cur_p1 > 0.8, cur_p2 < -0.7, and it is a faulty phase;

[0039] Condition 2: cur_p1 < -0.8, cur_p2 > 0.7, and both are fault phases;

[0040] Condition 3: cur_p1>0.8, cur_p2>0.7, and they are faulty phases;

[0041] Condition 4: cur_p1 < -0.8, cur_p2 < -0.7, and it is a faulty phase;

[0042] Methods for filtering arrays based on the correlation between intervals to be sorted:

[0043] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the first segment satisfy condition 1 or condition 2, then it is determined that the fault occurs between the two triggering devices, and the cur_p1 of the current pair between the two triggering devices is taken. ij 1-1n and cur_p2 ij 1-1n If condition 1 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-1n cur_p2 ij 1-1n If condition 2 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-1n -cur_p2 ij 1-1n );

[0044] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the second section satisfy condition 3 or condition 4, then it is determined that the fault occurs between the two triggering devices, and the cur_p1 of the current pair between the two triggering devices is taken. ij 1-2n and cur_p2 ij1-2n If condition 3 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-2n -cur_p2 ij 1-2n If condition 4 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-2n cur_p2 ij 1-2n );

[0045] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the third segment satisfy condition 1 or condition 2, then it is determined that the fault occurs between the two triggering devices, and the cur_p1 of the current pair between the two triggering devices is taken. ij 1-3n and cur_p2 ij 1-3n If condition 1 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-3n cur_p2 ij 1-3n If condition 2 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-3n -cur_p2 ij 1-3n );

[0046] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the fourth segment satisfy condition 3 or condition 4, then it is determined that the fault occurs between the two triggering devices, and the cur_p1 of the current pair between the two triggering devices is taken. ij 1-4n and cur_p2 ij 1-4n If condition 3 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-4n -cur_p2 ij 1-4n If condition 4 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-4n cur_p2 ij 1-4n );

[0047] After filtering out all interval fault correlation pairs, the interval fault correlation pairs (cur_p1) are... ij 1-1n cur_p2ij 1 -1n (cur_p1) ij 1-3n cur_p2 ij 1-3n (cur_p1) ij 1-2n cur_p2 ij 1-2n ) and (cur_p1 ij 1-4n cur_p2 ij 1-4n Together they form an array of unsorted correlation pairs within the interval;

[0048] Methods for filtering arrays based on relevance of unsorted data outside the region:

[0049] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the first segment satisfy condition 3 or condition 4, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 value of the current pair in these two triggering devices is taken. ij 1-1n and cur_p2 ij 1-1n If condition 3 is satisfied, then the external fault correlation pair (cur_p1) is formed. ij 1-1n cur_p2 ij 1-1n If condition 4 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-1n -cur_p2 ij 1-1n );

[0050] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the second segment satisfy condition 1 or condition 2, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 value of the current pair between these two triggering devices is taken. ij 1-2n and cur_p2 ij 1-2n If condition 1 is satisfied, then the external fault correlation pair (cur_p1) is formed. ij 1-2n -cur_p2 ij 1-2n If condition 2 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-2n cur_p2 ij1-2n );

[0051] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the third segment satisfy condition 3 or condition 4, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 of the current pair in these two triggering devices is taken. ij 1-3n and cur_p2 ij 1-3n If condition 3 is met, then the external fault correlation pair (cur_p1) is formed. ij 1-3n cur_p2 ij 1-3n If condition 4 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-3n -cur_p2 ij 1-3n );

[0052] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the fourth segment satisfy condition 1 or condition 2, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 of the current pair in these two triggering devices is taken. ij 1-4n and cur_p2 ij 1-4n If condition 1 is satisfied, then the external fault correlation pair (cur_p1) is formed. ij 1-4n -cur_p2 ij 1-4n If condition 2 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-4n cur_p2 ij 1-4n );

[0053] After filtering out all external fault correlation pairs, the external fault correlation pairs (cur_p1) are... ij 1-1n cur_p2 ij 1 -1n (cur_p1) ij 1-3n cur_p2 ij 1-3n (cur_p1) ij 1-2n cur_p2 ij 1-2n) and (cur_p1 ij 1-4n cur_p2 ij 1-4n Together they form an array of correlation pairs outside the region that are to be sorted.

[0054] By using four concise conditions, the complex physical laws of waveforms are transformed into truth judgments that can be directly executed by a computer, thus realizing the automated and standardized identification of faults within / outside the zone.

[0055] By setting a judgment order that prioritizes faults within a given area before those outside, the problem of avoiding interference from fault judgments outside the area that also meet the same conditions is solved when the fault is within the area. This refined construction method of dividing areas and conditions is like creating a dedicated fault identification logic for each segment of the network structure. It accurately extracts pairs that meet the conditions and encapsulates them into unsorted data units with correlation strength labels (the values ​​of cur_p1, cur_p2 or their inverses), achieving implicit integration of topology information and making subsequent sorting and location more accurate. At the same time, the logic of prioritizing the judgment of internal faults also conforms to the thinking habits of maintenance personnel in troubleshooting, improving the logical rationality and diagnostic efficiency of the method.

[0056] Preferably, selecting a pair of target correlation pairs according to a first preset rule and performing double-ended traveling wave localization within the interval specifically includes:

[0057] For the array of correlation pairs to be sorted in the specified interval, first based on cur_p2 ij Perform ascending sorting, if cur_p2 ij Equal, then based on cur_p1 ij Perform descending sorting to obtain a range-sorted array of related pairs.

[0058] After sorting the correlation pairs in the interval, take the positioning wave between the two triggering devices corresponding to the first correlation pair in the array, and use the double-ended wave method to locate the fault.

[0059] Preferably, selecting a pair of target correlation pairs according to the second preset rule and performing out-of-area double-ended traveling wave localization specifically includes:

[0060] For the array of correlation pairs outside the region to be sorted, first based on cur_p2 ij Perform descending sorting, if cur_p2 ij Equal, then based on cur_p1 ij Perform descending sorting to obtain the array of related pairs after sorting outside the region;

[0061] After sorting the correlation pairs outside the area, take the positioning wave between the two triggering devices corresponding to the first correlation pair in the array, and use the double-ended wave method for positioning.

[0062] Based on the dual-end traveling wave positioning results, if the located fault location is closer to a triggering device, it is determined that the fault occurs in the area outside that triggering device.

[0063] Based on a ranking rule using physical confidence levels, the crucial decision of selecting which pair of devices to use for traveling wave localization is cleverly automated and optimized. This not only avoids the randomness of manual selection but also ensures that each pair used for final two-way ranging has the most matching current characteristics and the highest data reliability, directly guaranteeing the accuracy and reliability of the final fault location results. Outside-area localization, through a combination of reference location and proximity-based judgment, provides valuable fault direction guidance even without real-area data, expanding the method's applicability.

[0064] A second aspect of the present invention provides an automatic fault selection and location system for power transmission and distribution network lines, comprising:

[0065] Multiple triggering devices are installed at various points along the line. At each point, triggering device A, triggering device B, and triggering device C are respectively installed on phase lines A, B, and C. The multiple triggering devices are grouped as follows:

[0066] Determine the time when the fault current first arrives at each triggering device on the line, and determine the location of the triggering device that arrives earliest as the first point in the entire line;

[0067] Based on the determined first point, the points on the line are first grouped into upstream and downstream sections; then, based on the first point, the points on the line are grouped into four segments. The upstream section includes all points from the first point towards the power supply side; the downstream section includes all other points on the line excluding the upstream section; the first segment includes the points in the upstream section through which the current flows from the power supply side to the first point; the second segment includes the points in the upstream section excluding the first segment; the third segment includes the points in the downstream section through which the current flows after passing the first point; and the fourth segment includes the points in the downstream section excluding the third segment.

[0068] The correlation calculation module is used to calculate the pair of currents between each phase triggering device of the A, B, and C phases of the triggering device at the first point and any phase triggering device of the A, B, and C phases at any other point. It is used to determine whether the pair of currents are in phase, and to determine the location point correlation index of the fault interval.

[0069] The fault phase identification module identifies the fault phase based on the current amplitude of all triggering devices at the triggering time;

[0070] The fault area filtering module is connected to the correlation calculation module and the fault phase judgment module. It is used to filter out the interval unsorted correlation pair array or the outside unsorted correlation pair array for fault location based on the phase correlation index, the location point correlation index, and the preset interval fault judgment conditions and outside fault judgment conditions, combined with the identified fault phase.

[0071] A traveling wave positioning module, connected to the fault area screening module, is used to select a target correlation pair from the interval unsorted correlation pair array according to a first preset rule when an interval unsorted correlation pair array exists, and to perform interval double-end traveling wave positioning on the two triggering devices corresponding to the target correlation pair; and

[0072] When there is only an array of out-of-area unsorted correlation pairs, a pair of target correlation pairs is selected from the array of out-of-area unsorted correlation pairs according to the second preset rule. Out-of-area double-ended traveling wave positioning is performed on the two triggering devices corresponding to the pair of target correlation pairs. Based on the positioning result, it is determined that the fault point is located in the outer area of ​​the triggering device that is closer to it.

[0073] A third aspect of the present invention provides a computer device, comprising:

[0074] One or more processors;

[0075] Memory, used to store one or more programs.

[0076] When the one or more programs are executed by the one or more processors, the one or more processors perform the steps of the automatic fault selection and location method for power transmission and distribution network lines as described above.

[0077] A fourth aspect of the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the automatic fault selection and location method for power transmission and distribution network lines as described above.

[0078] The fifth aspect of the present invention provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the steps of the automatic fault selection and location method for power transmission and distribution network lines as described above.

[0079] This invention has outstanding substantive features and significant progress compared to the prior art, specifically:

[0080] 1. The method of the present invention can realize automatic fault identification, line selection and precise location in power transmission and distribution lines, and is especially suitable for complex power distribution networks with T-junction branch structures.

[0081] 2. When there are installation problems such as phase sequence errors and reverse polarity in actual scenarios, the method of the present invention can further solve the automatic identification, line selection and precise positioning of faults in such scenarios. By correlation calculation and threshold screening, the method can handle equipment installation problems, correctly select lines and complete the final positioning. Attached Figure Description

[0082] Figure 1 This is a schematic diagram of a T-connection in a power transmission and distribution network, indicating the location of the fault.

[0083] Figure 2 This is a schematic diagram of a power transmission and distribution network line, illustrating problems such as incorrect phase sequence and reversed polarity.

[0084] Figure 3 This is a schematic diagram of a power transmission and distribution network line, in which the phase sequence and polarity are correct. It is assumed that the fault is a ground fault and the faulty phase is phase A.

[0085] Figure 4 This is a flowchart of the method of the present invention.

[0086] Figure 5 This is a schematic diagram of a power transmission and distribution network line, where phases A and B at point 1 are reversed.

[0087] Figure 6 This is a schematic diagram of a power transmission and distribution network line, with point 1 having the opposite polarity.

[0088] Figure 7 This is a schematic diagram of a power transmission and distribution network line, in which the phase sequence and polarity are correct. It is assumed that the fault is a bipolar fault, and the faulty phases are phase A and phase B.

[0089] Figure 8 This is a schematic diagram of a power transmission and distribution network line, in which the phase sequence and polarity are correct. It is assumed that the fault is a ground fault and the faulty phase is phase A. Detailed Implementation

[0090] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0091] Example 1

[0092] This embodiment provides a specific implementation case of a method for automatic fault selection and location in power transmission and distribution networks.

[0093] Figure 3The diagram illustrates a power transmission and distribution network line structure with five points on the line. At each point, corresponding triggering devices A, B, and C are installed on phases A, B, and C. Assume the fault is a ground fault, occurring at the location indicated by the red arrow in the diagram, and that point 5 is the first point.

[0094] The specific implementation method includes the following steps, such as: Figure 4 As shown:

[0095] (1) Trigger device grouping;

[0096] Determine the time when the fault current first arrives at each triggering device on the line, and determine the location of the triggering device that arrives earliest as the first point in the entire line;

[0097] In this embodiment, it is assumed that the fault current first arrives at the triggering device 5A on the line at the earliest time, then it can be determined that:

[0098] First point: Point 5 (including: triggering device 5A, triggering device 5B and triggering device 5C);

[0099] First section: Point 1 (including: triggering device 1A, triggering device 1B and triggering device 1C), Point 2 (including: triggering device 2A, triggering device 2B and triggering device 2C);

[0100] Second section: Point 3 (including: triggering device 3A, triggering device 3B and triggering device 3C);

[0101] Third section: Point 6 (including: triggering device 6A, triggering device 6B and triggering device 6C);

[0102] Fourth section: Point 4 (including: triggering device 4A, triggering device 4B and triggering device 4C).

[0103] (2) Correlation calculation;

[0104] Calculate the phase correlation of current pairs between the three triggering devices A, B, and C at the first point and the three triggering devices A, B, and C at other points, and denote this as cur_p1. ij 1-mn This is used to determine whether the current is in phase; and

[0105] Calculate the position point correlation of the current pairs between the three triggering devices A, B, and C at the first point and the three triggering devices A, B, and C at other points, denoted as cur_p2. ij 1-mn This is used to determine whether the fault occurred between or outside the two triggering devices;

[0106] Where i represents the three phases, i = A, B, C; j represents the three phases, j = A, B, C; m represents the segment, m = 1, 2, 3, 4; n represents the nth point in the segment, n = 1, 2, ..., N;

[0107] When calculating phase correlation, the current pair used for calculation is the current waveform of the corresponding trigger device for two cycles, from two cycles before the fault occurrence time to four cycles before the fault occurrence time.

[0108] When calculating the correlation of location points, the current pairs used for calculation are the current waveform data points 10 points after the time of the fault occurrence of the corresponding triggering device.

[0109] The calculation results obtained in this embodiment are shown in Table 1.

[0110] (3) Fault phase identification;

[0111] Compare the current at the triggering moment of all triggering devices, and take the maximum value as the maximum current value. If the current value at the triggering moment of any triggering device is greater than or equal to 80% of the maximum current value, then the phase where the triggering device is located is the faulty phase.

[0112] The judgment results obtained in this embodiment are shown in Table 1.

[0113] (4) Fault area screening;

[0114] (41) Interval fault screening:

[0115] For the results of the correlation calculation, take the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the first segment, and compare them with condition 1 or condition 2. If condition 1 or condition 2 is met, it is determined that the fault occurs between the two triggering devices and is screened as an interval fault.

[0116] Take the cur_p1 of the current pair from the two triggering devices. ij 1-1n and cur_p2 ij 1-1n If condition 1 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-1n cur_p2 ij 1-1n If condition 2 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-1n -cur_p2 ij 1-1n ).

[0117] For the results of the correlation calculation, take the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the second section, and compare them with condition 3 or condition 4. If condition 3 or condition 4 is met, it is determined that the fault occurs between the two triggering devices and is screened as an interval fault.

[0118] Take the cur_p1 of the current pair from the two triggering devices. ij 1-2n and cur_p2 ij 1-2n If condition 3 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-2n -cur_p2 ij 1-2n If condition 4 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-2n cur_p2 ij 1-2n ).

[0119] For the results of the correlation calculation, take the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the third section, and compare them with condition 1 or condition 2. If condition 1 or condition 2 is met, it is determined that the fault occurs between the two triggering devices and is screened as an interval fault.

[0120] Take the cur_p1 of the current pair from the two triggering devices. ij 1-3n and cur_p2 ij 1-3n If condition 1 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-3n cur_p2 ij 1-3n If condition 2 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-3n -cur_p2 ij 1-3n ).

[0121] For the results of the correlation calculation, take the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the fourth segment, and compare them with condition 3 or condition 4. If condition 3 or condition 4 is met, it is determined that the fault occurs between the two triggering devices and is screened as an interval fault.

[0122] Take the cur_p1 of the current pair from the two triggering devices. ij1-4n and cur_p2 ij 1-4n If condition 3 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-4n cur_p2 ij 1-4n If condition 4 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-4n cur_p2 ij 1-4n ).

[0123] Condition 1: cur_p1 > 0.8, cur_p2 < -0.7, and it is a faulty phase;

[0124] Condition 2: cur_p1 < -0.8, cur_p2 > 0.7, and both are fault phases;

[0125] Condition 3: cur_p1>0.8, cur_p2>0.7, and they are faulty phases;

[0126] Condition 4: cur_p1 <-0.8, cur_p2 <-0.7, and is a faulty phase.

[0127] After filtering out all interval fault correlation pairs, the interval fault correlation pairs (cur_p1) are... ij 1-1n cur_p2 ij 1 -1n (cur_p1) ij 1-3n cur_p2 ij 1-3n (cur_p1) ij 1-2n cur_p2 ij 1-2n ) and (cur_p1 ij 1-4n cur_p2 ij 1-4n These together form an array of interval correlation pairs for fault location.

[0128] (42) If the array of correlation pairs to be sorted in the interval is not empty, then perform (51) interval wavy positioning;

[0129] If the array of correlation pairs to be sorted in the interval is empty, then perform (43) out-of-interval fault screening.

[0130] (43) Screening of faults outside the area:

[0131] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the first segment satisfy condition 3 or condition 4, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 value of the current pair in these two triggering devices is taken. ij 1-1n and cur_p2 ij 1-1n If condition 3 is satisfied, then the external fault correlation pair (cur_p1) is formed. ij 1-1n cur_p2 ij 1-1n If condition 4 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-1n -cur_p2 ij 1-1n );

[0132] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the second segment satisfy condition 1 or condition 2, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 value of the current pair between these two triggering devices is taken. ij 1-2n and cur_p2 ij 1-2n If condition 1 is satisfied, then the external fault correlation pair (cur_p1) is formed. ij 1-2n -cur_p2 ij 1-2n If condition 2 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-2n cur_p2 ij 1-2n );

[0133] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the third segment satisfy condition 3 or condition 4, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 of the current pair in these two triggering devices is taken. ij 1-3n and cur_p2 ij 1-3n If condition 3 is met, then the external fault correlation pair (cur_p1) is formed. ij 1-3n cur_p2 ij 1-3n If condition 4 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij1-3n -cur_p2 ij 1-3n );

[0134] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the fourth segment satisfy condition 1 or condition 2, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 of the current pair in these two triggering devices is taken. ij 1-4n and cur_p2 ij 1-4n If condition 1 is satisfied, then the external fault correlation pair (cur_p1) is formed. ij 1-4n -cur_p2 ij 1-4n If condition 2 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-4n cur_p2 ij 1-4n );

[0135] After filtering out all external fault correlation pairs, the external fault correlation pairs (cur_p1) are... ij 1-1n cur_p2 ij 1 -1n (cur_p1) ij 1-3n cur_p2 ij 1-3n (cur_p1) ij 1-2n cur_p2 ij 1-2n ) and (cur_p1 ij 1-4n cur_p2 ij 1-4n Together they form an array of out-of-area correlation pairs for fault location, and then (52) out-of-area traveling wave location is performed.

[0136] The results of the fault area screening obtained in this embodiment are shown in Table 1.

[0137] Table 1. Correlation Calculation Results and Fault Area Screening Results

[0138] 5A and 1A <![CDATA[cur_p1 AA 1-11 ]]> <![CDATA[cur_p2 AA 1-11 ]]> （0.92，-0.81） yes 1 1、2 Interval fault 5A and 1B <![CDATA[cur_p1 AB 1-11 ]]> <![CDATA[cur_p2 AB 1-11 ]]> （0.41，-0.5） no / 1、2 / 5A and 1C <![CDATA[cur_p1 AC 1-11 ]]> <![CDATA[cur_p2 AC 1-11 ]]> （0.5，-0.3） no / 1、2 / 5B and 1A <![CDATA[cur_p1 BA 1-11 ]]> <![CDATA[cur_p2 BA 1-11 ]]> （-0.52，-0.43） no / 1、2 / 5B and 1B <![CDATA[cur_p1 BB 1-11 ]]> <![CDATA[cur_p2 BB 1-11 ]]> （0.9，0.75） no 3 1、2 / 5B and 1C <![CDATA[cur_p1 BC 1-11 ]]> <![CDATA[cur_p2 BC 1-11 ]]> （0.56，0.43） no / 1、2 / 5C and 1A <![CDATA[cur_p1 CA 1-11 ]]> <![CDATA[cur_p2 CA 1-11 ]]> （0.44，-0.46） no / 1、2 / 5C and 1B <![CDATA[cur_p1 CB 1-11 ]]> <![CDATA[cur_p2 CB 1-11 ]]> （-0.55，0.6） no / 1、2 / 5C and 1C <![CDATA[cur_p1 CC 1-11 ]]> <![CDATA[cur_p2 CC 1-11 ]]> （0.89，0.78） no 3 1、2 / 5A and 2A <![CDATA[cur_p1 AA 1-12 ]]> <![CDATA[cur_p2 AA 1-12 ]]> （0.83，-0.75） yes 1 1、2 Interval fault 5A and 2B <![CDATA[cur_p1 AB 1-12 ]]> <![CDATA[cur_p2 AB 1-12 ]]> （0.48，-0.49） no / 1、2 / 5A and 2C <![CDATA[cur_p1 AC 1-12 ]]> <![CDATA[cur_p2 AC 1-12 ]]> （0.3，-0.44） no / 1、2 / 5B and 2A <![CDATA[cur_p1 BA 1-12 ]]> <![CDATA[cur_p2 BA 1-12 ]]> （-0.43，-0.34） no / 1、2 / 5B and 2B <![CDATA[cur_p1 BB 1-12 ]]> <![CDATA[cur_p2 BB 1-12 ]]> （0.77，0.78） no / 1、2 / 5B and 2C <![CDATA[cur_p1 BC 1-12 ]]> <![CDATA[cur_p2 BC 1-12 ]]> （0.51，0.34） no / 1、2 / 5C and 2A <![CDATA[cur_p1 CA 1-12 ]]> <![CDATA[cur_p2 CA 1-12 ]]> （0.47，-0.36） no / 1、2 / 5C and 2B <![CDATA[cur_p1 CB 1-12 ]]> <![CDATA[cur_p2 CB 1-12 ]]> （-0.54，0.45） no / 1、2 / 5C and 2C <![CDATA[cur_p1 CC 1-12 ]]> <![CDATA[cur_p2 CC 1-12 ]]> （0.75，0.86） no / 1、2 / 5A and 3A <![CDATA[cur_p1 AA 1-21 ]]> <![CDATA[cur_p2 AA 1-21 ]]> （0.93，0.86） yes 4 3、4 Interval fault 5A and 3B <![CDATA[cur_p1 AB 1-21 ]]> <![CDATA[cur_p2 AB 1-21 ]]> （0.39，0.36） no / 3、4 / 5A and 3C <![CDATA[cur_p1 AC 1-21 ]]> <![CDATA[cur_p2 AC 1-21 ]]> （0.32，0.47） no / 3、4 / 5B and 3A <![CDATA[cur_p1 BA 1-21 ]]> <![CDATA[cur_p2 BA 1-21 ]]> （-0.48，0.26） no / 3、4 / 5B and 3B <![CDATA[cur_p1 BB 1-21 ]]> <![CDATA[cur_p2 BB 1-21 ]]> （0.79，0.68） no / 3、4 / 5B and 3C <![CDATA[cur_p1 BC 1-21 ]]> <![CDATA[cur_p2 BC 1-21 ]]> （0.55，0.48） no / 3、4 / 5C and 3A <![CDATA[cur_p1 CA 1-21 ]]> <![CDATA[cur_p2 CA 1-21 ]]> （0.44，0.46） no / 3、4 / 5C and 3B <![CDATA[cur_p1 CB 1-21 ]]> <![CDATA[cur_p2 CB 1-21 ]]> （-0.39，-0.36） no / 3、4 / 5C and 3C <![CDATA[cur_p1 CC 1-21 ]]> <![CDATA[cur_p2 CC 1-21 ]]> （0.86,0.76） no 3 3、4 / 5A and 4A <![CDATA[cur_p1 AA 1-41 ]]> <![CDATA[cur_p2 AA 1-41 ]]> （0.94，0.77） yes 3 3、4 Interval fault 5A and 4B <![CDATA[cur_p1 AB 1-41 ]]> <![CDATA[cur_p2 AB 1-41 ]]> （0.35，-0.6） no / 3、4 / 5A and 4C <![CDATA[cur_p1 AC 1-41 ]]> <![CDATA[cur_p2 AC 1-41 ]]> （0.4，-0.46） no / 3、4 / 5B and 4A <![CDATA[cur_p1 BA 1-41 ]]> <![CDATA[cur_p2 BA 1-41 ]]> （-0.37，-0.6） no / 3、4 / 5B and 4B <![CDATA[cur_p1 BB 1-41 ]]> <![CDATA[cur_p2 BB 1-41 ]]> （0.9，0.76） no 3 3、4 / 5B and 4C <![CDATA[cur_p1 BC 1-41 ]]> <![CDATA[cur_p2 BC 1-41 ]]> （0.45，0.34） no / 3、4 / 5C and 4A <![CDATA[cur_p1 CA 1-41 ]]> <![CDATA[cur_p2 CA 1-41 ]]> （0.47，0.26） no / 3、4 / 5C and 4B <![CDATA[cur_p1 CB 1-41 ]]> <![CDATA[cur_p2 CB 1-41 ]]> （-0.33，0.36） no / 3、4 / 5C and 4C <![CDATA[cur_p1 CC 1-41 ]]> <![CDATA[cur_p2 CC 1-41 ]]> （0.74，0.84） no / 3、4 / 5A and 6A <![CDATA[cur_p1 AA 1-31 ]]> <![CDATA[cur_p2 AA 1-31 ]]> （0.9，0.96） yes 3 1、2 / 5A and 6B <![CDATA[cur_p1 AB 1-31 ]]> <![CDATA[cur_p2 AB 1-31 ]]> （0.6，0.54） no / 1、2 / 5A and 6C <![CDATA[cur_p1 AC 1-31 ]]> <![CDATA[cur_p2 AC 1-31 ]]> （0.38，0.46） no / 1、2 / 5B and 6A <![CDATA[cur_p1 BA 1-31 ]]> <![CDATA[cur_p2 BA 1-31 ]]> （-0.41，0.55） no / 1、2 / 5B and 6B <![CDATA[cur_p1 BB 1-31 ]]> <![CDATA[cur_p2 BB 1-31 ]]> （0.79，0.86） no / 1、2 / 5B and 6C <![CDATA[cur_p1 BC 1-31 ]]> <![CDATA[cur_p2 BC 1-31 ]]> （0.48，0.43） no / 1、2 / 5C and 6A <![CDATA[cur_p1 CA 1-31 ]]> <![CDATA[cur_p2 CA 1-31 ]]> （0.55，-0.4） no / 1、2 / 5C and 6B <![CDATA[cur_p1 CB 1-31 ]]> <![CDATA[cur_p2 CB 1-31 ]]> （-0.56，-0.34） no / 1、2 / 5C and 6C <![CDATA[cur_p1 CC 1-31 ]]> <![CDATA[cur_p2 CC 1-31 ]]> （0.88，0.96） no 3 1、2 /

[0139] Based on Table 1, phase A is determined to be the faulty phase, and the selected interval correlation pairs to be sorted are as follows:

[0140] [(0.92, -0.81), (0.8, -0.75), (0.93, 0.86), (0.94, 0.77)]

[0141] If the relevant section and conditions are met, the specific value of the original correlation pair needs to be taken as the opposite; then

[0142] The final obtained correlation array within the interval is:

[0143] [(0.92, -0.81), (0.8, -0.75), (0.93, -0.86), (0.94, -0.77)]

[0144] That is, if the correlation array within the interval is not empty, interval traveling wave positioning is performed.

[0145] Sort the correlation array within the interval, and the sorting result is:

[0146] [(0.93, -0.86), (0.92, -0.81), (0.94, -0.77), (0.8, -0.75)]

[0147] In the sorted correlation pair array, the first one is the correlation pair (0.93, -0.86). The two sub-trigger devices corresponding to this correlation pair are trigger device 5A and trigger device 3A. When using the double-ended traveling wave method for positioning, the positioning traveling wave between trigger device 5A and trigger device 3A is used for calculation, and thus the fault location is obtained.

[0148] In the present invention, the phase correlation coefficient cur_p1 is mainly used to reflect the consistency of phase sequence and polarity between different devices. By setting the threshold of cur_p1, problems such as incorrect phase sequence connection or reverse polarity connection during the installation of trigger devices can be effectively identified and excluded. When -0.8 < cur_p1 < 0.8, it indicates that the correlation between the corresponding phases of the two devices is weak, and there may be an incorrect phase sequence correspondence relationship; when cur_p1 < -0.8, it means that there is a strong negative correlation between the corresponding phases of the two devices, usually caused by the opposite wiring direction of the devices. Therefore, the threshold setting of cur_p1 can ensure that the line selection and positioning analysis are based on the correct signal input of phase sequence and polarity;

[0149] The position point correlation coefficient cur_p2 reflects the correlation of transient currents between devices when a fault occurs, mainly to judge whether the fault occurs inside or outside the interval, but the sign of the coefficient needs to be determined in combination with the section;

[0150] By reasonably setting the threshold of cur_p2 and combining the judgment result of cur_p1, the interference of incorrect polarity or non-fault phases can be effectively removed, and only the phase information related to the fault is retained, providing reliable data support for subsequent line selection and fault location.

[0151] Regarding the correlation coefficient cur_p1:

[0152] ① Troubleshooting phase sequence errors:

[0153] by Figure 5 For example, the trigger device 1A for collecting the current of phase A at point 1 is installed on phase B, that is, phases A and B at point 1 are reversed. The phase sequence at point 5 is correct. So when calculating the correlation between trigger device 1A and trigger device 5A, the correlation between trigger device 1B and trigger device 5A is actually calculated. By setting the threshold cur_p1>0.8, the case of incorrect phase sequence can be eliminated.

[0154] ② Eliminating polarity errors:

[0155] by Figure 6 For example, the phase sequence of point 1 and point 5 is correct, but the direction of point 1 is reversed, so cur_p1 < -0.8.

[0156] Regarding the correlation coefficient cur_p2 of the location points:

[0157] The cur_p2 threshold is set to 0.7;

[0158] In the case of polarity error: cur_p2<-0.7, the correlation coefficient combination of faulty phase and non-faulty phase will be excluded, and the correlation between faulty phases will be retained.

[0159] Problems that can be solved by sorting:

[0160] by Figure 3 For example, if the fault occurs at the arrow position, triggering devices 5A and 1A, 2A, 3A, and 4A can all be selected. The specific two triggering devices to be selected are determined by the first one in the sorting order, whichever device has the strongest correlation with the waveform is selected for traveling wave localization.

[0161] Example 2

[0162] The difference between this embodiment and Embodiment 1 is that it is assumed that the fault is a short circuit fault.

[0163] Figure 7 The diagram illustrates a power transmission and distribution network line structure with five points on the line. At each point, corresponding triggering devices A, B, and C are installed on phases A, B, and C. Assume the fault is a short-circuit fault, occurring at the location indicated by the red arrow in the diagram, i.e., faulty phases A and B, with point 5 being the first point.

[0164] The results of the fault area screening obtained in this embodiment are shown in Table 2.

[0165] Table 2. Correlation Calculation Results and Fault Area Screening Results

[0166] 5A and 1A <![CDATA[cur_p1 AA 1-11 ]]> <![CDATA[cur_p2 AA 1-11 ]]> （0.92，-0.81） yes 1 1、2 Interval fault 5A and 1B <![CDATA[cur_p1 AB 1-11 ]]> <![CDATA[cur_p2 AB 1-11 ]]> （0.41，-0.5） no / 1、2 / 5A and 1C <![CDATA[cur_p1 AC 1-11 ]]> <![CDATA[cur_p2 AC 1-11 ]]> （0.5，-0.3） no / 1、2 / 5B and 1A <![CDATA[cur_p1 BA 1-11 ]]> <![CDATA[cur_p2 BA 1-11 ]]> （-0.52，-0.43） no / 1、2 / 5B and 1B <![CDATA[cur_p1 BB 1-11 ]]> <![CDATA[cur_p2 BB 1-11 ]]> （0.9，-0.75） yes 1 1、2 Interval fault 5B and 1C <![CDATA[cur_p1 BC 1-11 ]]> <![CDATA[cur_p2 BC 1-11 ]]> （0.56，0.43） no / 1、2 / 5C and 1A <![CDATA[cur_p1 CA 1-11 ]]> <![CDATA[cur_p2 CA 1-11 ]]> （0.44，-0.46） no / 1、2 / 5C and 1B <![CDATA[cur_p1 CB 1-11 ]]> <![CDATA[cur_p2 CB 1-11 ]]> （-0.55，0.6） no / 1、2 / 5C and 1C <![CDATA[cur_p1 CC 1-11 ]]> <![CDATA[cur_p2 CC 1-11 ]]> （0.89，0.78） no 3 1、2 / 5A and 2A <![CDATA[cur_p1 AA 1-12 ]]> <![CDATA[cur_p2 AA 1-12 ]]> （0.83，-0.75） yes 1 1、2 Interval fault 5A and 2B <![CDATA[cur_p1 AB 1-12 ]]> <![CDATA[cur_p2 AB 1-12 ]]> （0.48，-0.49） no / 1、2 / 5A and 2C <![CDATA[cur_p1 AC 1-12 ]]> <![CDATA[cur_p2 AC 1-12 ]]> （0.3，-0.44） no / 1、2 / 5B and 2A <![CDATA[cur_p1 BA 1-12 ]]> <![CDATA[cur_p2 BA 1-12 ]]> （-0.43，-0.34） no / 1、2 / 5B and 2B <![CDATA[cur_p1 BB 1-12 ]]> <![CDATA[cur_p2 BB 1-12 ]]> （0.77，-0.78） yes / 1、2 / 5B and 2C <![CDATA[cur_p1 BC 1-12 ]]> <![CDATA[cur_p2 BC 1-12 ]]> （0.51，0.34） no / 1、2 / 5C and 2A <![CDATA[cur_p1 CA 1-12 ]]> <![CDATA[cur_p2 CA 1-12 ]]> （0.47，-0.36） no / 1、2 / 5C and 2B <![CDATA[cur_p1 CB 1-12 ]]> <![CDATA[cur_p2 CB 1-12 ]]> （-0.54，0.45） no / 1、2 / 5C and 2C <![CDATA[cur_p1 CC 1-12 ]]> <![CDATA[cur_p2 CC 1-12 ]]> （0.75，0.86） no / 1、2 / 5A and 3A <![CDATA[cur_p1 AA 1-21 ]]> <![CDATA[cur_p2 AA 1-21 ]]> （0.93，0.86） yes 4 3、4 Interval fault 5A and 3B <![CDATA[cur_p1 AB 1-21 ]]> <![CDATA[cur_p2 AB 1-21 ]]> （0.39，0.36） no / 3、4 / 5A and 3C <![CDATA[cur_p1 AC 1-21 ]]> <![CDATA[cur_p2 AC 1-21 ]]> （0.32，0.47） no / 3、4 / 5B and 3A <![CDATA[cur_p1 BA 1-21 ]]> <![CDATA[cur_p2 BA 1-21 ]]> （-0.48，0.26） no / 3、4 / 5B and 3B <![CDATA[cur_p1 BB 1-21 ]]> <![CDATA[cur_p2 BB 1-21 ]]> （0.79，0.68） yes / 3、4 / 5B and 3C <![CDATA[cur_p1 BC 1-21 ]]> <![CDATA[cur_p2 BC 1-21 ]]> （0.55，0.48） no / 3、4 / 5C and 3A <![CDATA[cur_p1 CA 1-21 ]]> <![CDATA[cur_p2 CA 1-21 ]]> （0.44，0.46） no / 3、4 / 5C and 3B <![CDATA[cur_p1 CB 1-21 ]]> <![CDATA[cur_p2 CB 1-21 ]]> （-0.39，-0.36） no / 3、4 / 5C and 3C <![CDATA[cur_p1 CC 1-21 ]]> <![CDATA[cur_p2 CC 1-21 ]]> （0.86,0.76） no 3 3、4 / 5A and 4A <![CDATA[cur_p1 AA 1-41 ]]> <![CDATA[cur_p2 AA 1-41 ]]> （0.94，0.77） yes 3 3、4 Interval fault 5A and 4B <![CDATA[cur_p1 AB 1-41 ]]> <![CDATA[cur_p2 AB 1-41 ]]> （0.35，-0.6） no / 3、4 / 5A and 4C <![CDATA[cur_p1 AC 1-41 ]]> <![CDATA[cur_p2 AC 1-41 ]]> （0.4，-0.46） no / 3、4 / 5B and 4A <![CDATA[cur_p1 BA 1-41 ]]> <![CDATA[cur_p2 BA 1-41 ]]> （-0.37，-0.6） no / 3、4 / 5B and 4B <![CDATA[cur_p1 BB 1-41 ]]> <![CDATA[cur_p2 BB 1-41 ]]> （0.9，0.76） yes 3 3、4 Interval fault 5B and 4C <![CDATA[cur_p1 BC 1-41 ]]> <![CDATA[cur_p2 BC 1-41 ]]> （0.45，0.34） no / 3、4 / 5C and 4A <![CDATA[cur_p1 CA 1-41 ]]> <![CDATA[cur_p2 CA 1-41 ]]> （0.47，0.26） no / 3、4 / 5C and 4B <![CDATA[cur_p1 CB 1-41 ]]> <![CDATA[cur_p2 CB 1-41 ]]> （-0.33，0.36） no / 3、4 / 5C and 4C <![CDATA[cur_p1 CC 1-41 ]]> <![CDATA[cur_p2 CC 1-41 ]]> （0.74，0.84） no / 3、4 / 5A and 6A <![CDATA[cur_p1 AA 1-31 ]]> <![CDATA[cur_p2 AA 1-31 ]]> （0.9，0.96） yes 3 1、2 / 5A and 6B <![CDATA[cur_p1 AB 1-31 ]]> <![CDATA[cur_p2 AB 1-31 ]]> （0.6，0.54） no / 1、2 / 5A and 6C <![CDATA[cur_p1 AC 1-31 ]]> <![CDATA[cur_p2 AC 1-31 ]]> （0.38，0.46） no / 1、2 / 5B and 6A <![CDATA[cur_p1 BA 1-31 ]]> <![CDATA[cur_p2 BA 1-31 ]]> （-0.41，0.55） no / 1、2 / 5B and 6B <![CDATA[cur_p1 BB 1-31 ]]> <![CDATA[cur_p2 BB 1-31 ]]> （0.79，0.86） yes / 1、2 / 5B and 6C <![CDATA[cur_p1 BC 1-31 ]]> <![CDATA[cur_p2 BC 1-31 ]]> （0.48，0.43） no / 1、2 / 5C and 6A <![CDATA[cur_p1 CA 1-31 ]]> <![CDATA[cur_p2 CA 1-31 ]]> （0.55，-0.4） no / 1、2 / 5C and 6B <![CDATA[cur_p1 CB 1-31 ]]> <![CDATA[cur_p2 CB 1-31 ]]> （-0.56，-0.34） no / 1、2 / 5C and 6C <![CDATA[cur_p1 CC 1-31 ]]> <![CDATA[cur_p2 CC 1-31 ]]> （0.88，0.96） no 3 1、2 /

[0167] Based on Table 2, phases A and B are determined to be faulty phases. The selected interval correlation pairs to be sorted are as follows:

[0168] [(0.92, -0.81), (0.9, -0.75), (0.8, -0.75), (0.93, 0.86), (0.94, 0.77), (0.9, 0.76)]

[0169] To satisfy the relevant segments and conditions, it is necessary to take the negative of a specific value of the original correlation pair; then...

[0170] The final inter-interval correlation array is as follows:

[0171] [(0.92, -0.81), (0.9, -0.75), (0.8, -0.75), (0.93, -0.86), (0.94, -0.77), (0.9, -0.76)]

[0172] That is, if the correlation array within the interval is not empty, interval wave positioning is performed.

[0173] Sort the correlation array within the interval, and the sorting result is as follows:

[0174] [(0.93, -0.86), (0.92, -0.81), (0.94, -0.77), (0.9, -0.76), (0.9, -0.75), (0.8, -0.75)]

[0175] After sorting, the first correlation pair in the correlation pair array is the correlation pair (0.93, -0.86), which corresponds to two sub-triggering devices, triggering device 5A and triggering device 3A. When using the double-ended traveling wave method for positioning, the positioning traveling wave between triggering device 5A and triggering device 3A is used for calculation to obtain the fault location.

[0176] It should be noted that if a three-phase fault occurs, the location method is the same, and no further examples will be given here.

[0177] Example 3

[0178] The difference between this embodiment and Embodiment 1 is that:

[0179] Figure 8The diagram illustrates a power transmission and distribution network line structure with five points on the line. At each point, corresponding triggering devices A, B, and C are installed on phases A, B, and C. Assume the fault is a ground fault, occurring at the location indicated by the red arrow in the diagram (fault phase A), and that point 4 is the first point.

[0180] First point: Point 4 (including: triggering device 4A, triggering device 4B and triggering device 4C);

[0181] First section: Point 1 (including: triggering device 1A, triggering device 1B and triggering device 1C), Point 2 (including: triggering device 2A, triggering device 2B and triggering device 2C);

[0182] Second section: Point 3 (including: triggering device 3A, triggering device 3B and triggering device 3C);

[0183] Third section: None;

[0184] Fourth section: Point 5 (including triggering device 5A, triggering device 5B and triggering device 5C), Point 6 (including triggering device 6A, triggering device 6B and triggering device 6C).

[0185] The results of the fault area screening obtained in this embodiment are shown in Table 3.

[0186] Table 3. Correlation Calculation Results and Fault Area Screening Results

[0187] 4A and 1A <![CDATA[cur_p1 AA 1-11 ]]> <![CDATA[cur_p2 AA 1-11 ]]> （0.92，0.81） yes 3 3、4 External fault 4A and 1B <![CDATA[cur_p1 AB 1-11 ]]> <![CDATA[cur_p2 AB 1-11 ]]> （0.41，-0.5） no / 3、4 / 4A and 1C <![CDATA[cur_p1 AC 1-11 ]]> <![CDATA[cur_p2 AC 1-11 ]]> （0.5，-0.3） no / 3、4 / 4B and 1A <![CDATA[cur_p1 BA 1-11 ]]> <![CDATA[cur_p2 BA 1-11 ]]> （-0.52，-0.43） no / 3、4 / 4B and 1B <![CDATA[cur_p1 BB 1-11 ]]> <![CDATA[cur_p2 BB 1-11 ]]> （0.9，0.75） no / 3、4 / 4B and 1C <![CDATA[cur_p1 BC 1-11 ]]> <![CDATA[cur_p2 BC 1-11 ]]> （0.56，0.43） no / 3、4 / 4C and 1A <![CDATA[cur_p1 CA 1-11 ]]> <![CDATA[cur_p2 CA 1-11 ]]> （0.44，-0.46） no / 3、4 / 4C and 1B <![CDATA[cur_p1 CB 1-11 ]]> <![CDATA[cur_p2 CB 1-11 ]]> （-0.55，0.6） no / 3、4 / 4C and 1C <![CDATA[cur_p1 CC 1-11 ]]> <![CDATA[cur_p2 CC 1-11 ]]> （0.89，0.78） no / 3、4 / 4A and 2A <![CDATA[cur_p1 AA 1-12 ]]> <![CDATA[cur_p2 AA 1-12 ]]> （0.83，0.75） yes 3 3、4 External fault 4A and 2B <![CDATA[cur_p1 AB 1-12 ]]> <![CDATA[cur_p2 AB 1-12 ]]> （0.48，-0.49） no / 3、4 / 4A and 2C <![CDATA[cur_p1 AC 1-12 ]]> <![CDATA[cur_p2 AC 1-12 ]]> （0.3，-0.44） no / 3、4 / 4B and 2A <![CDATA[cur_p1 BA 1-12 ]]> <![CDATA[cur_p2 BA 1-12 ]]> （-0.43，-0.34） no / 3、4 / 4B and 2B <![CDATA[cur_p1 BB 1-12 ]]> <![CDATA[cur_p2 BB 1-12 ]]> （0.77，0.78） no / 3、4 / 4B and 2C <![CDATA[cur_p1 BC 1-12 ]]> <![CDATA[cur_p2 BC 1-12 ]]> （0.51，0.34） no / 3、4 / 4C and 2A <![CDATA[cur_p1 CA 1-121 ]]> <![CDATA[cur_p2 CA 1-12 ]]> （0.47，-0.36） no / 3、4 / 4C and 2B <![CDATA[cur_p1 CB 1-12 ]]> <![CDATA[cur_p2 CB 1-12 ]]> （-0.54，0.45） no / 3、4 / 4C and 2C <![CDATA[cur_p1 CC 1-12 ]]> <![CDATA[cur_p2 CC 1-12 ]]> （0.75，0.86） no / 3、4 / 4A and 3A <![CDATA[cur_p1 AA 1-21 ]]> <![CDATA[cur_p2 AA 1-21 ]]> （0.93，-0.86） yes 1 1、2 External fault 4A and 3B <![CDATA[cur_p1 AB 1-21 ]]> <![CDATA[cur_p2 AB 1-21 ]]> （0.39，0.36） no / 1、2 / 4A and 3C <![CDATA[cur_p1 AC 1-21 ]]> <![CDATA[cur_p2 AC 1-21 ]]> （0.32，0.47） no / 1、2 / 4B and 3A <![CDATA[cur_p1 BA 1-21 ]]> <![CDATA[cur_p2 BA 1-21 ]]> （-0.48，0.26） no / 1、2 / 4B and 3B <![CDATA[cur_p1 BB 1-21 ]]> <![CDATA[cur_p2 BB 1-21 ]]> （0.79，0.68） no / 1、2 / 4B and 3C <![CDATA[cur_p1 BC 1-21 ]]> <![CDATA[cur_p2 BC 1-21 ]]> （0.55，0.48） no / 1、2 / 4C and 3A <![CDATA[cur_p1 CA 1-21 ]]> <![CDATA[cur_p2 CA 1-21 ]]> （0.44，0.46） no / 1、2 / 4C and 3B <![CDATA[cur_p1 CB 1-21 ]]> <![CDATA[cur_p2 CB 1-21 ]]> （-0.39，-0.36） no / 1、2 / 4C and 3C <![CDATA[cur_p1 CC 1-21 ]]> <![CDATA[cur_p2 CC 1-21 ]]> （0.86,0.76） no / 1、2 / 4A and 5A <![CDATA[cur_p1 AA 1-31 ]]> <![CDATA[cur_p2 AA 1-31 ]]> （0.94，-0.77） yes 1 1、2 External fault 4A and 5B <![CDATA[cur_p1 AB 1-31 ]]> <![CDATA[cur_p2 AB 1-31 ]]> （0.35，-0.6） no / 1、2 / 4A and 5C <![CDATA[cur_p1 AC 1-31 ]]> <![CDATA[cur_p2 AC 1-31 ]]> （0.4，-0.46） no / 1、2 / 4B and 5A <![CDATA[cur_p1 BA 1-31 ]]> <![CDATA[cur_p2 BA 1-31 ]]> （-0.37，-0.6） no / 1、2 / 4B and 5B <![CDATA[cur_p1 BB 1-31 ]]> <![CDATA[cur_p2 BB 1-31 ]]> （0.9，0.76） no / 1、2 / 4B and 5C <![CDATA[cur_p1 BC 1-31 ]]> <![CDATA[cur_p2 BC 1-31 ]]> （0.45，0.34） no / 1、2 / 4C and 5A <![CDATA[cur_p1 CA 1-31 ]]> <![CDATA[cur_p2 CA 1-31 ]]> （0.47，0.26） no / 1、2 / 4C and 5B <![CDATA[cur_p1 CB 1-31 ]]> <![CDATA[cur_p2 CB 1-31 ]]> （-0.33，0.36） no / 1、2 / 4C and 5C <![CDATA[cur_p1 CC 1-31 ]]> <![CDATA[cur_p2 CC 1-31 ]]> （0.74，0.84） no / 1、2 / 4A and 6A <![CDATA[cur_p1 AA 1-32 ]]> <![CDATA[cur_p2 AA 1-32 ]]> （0.9，-0.96） yes 1 1、2 External fault 4A and 6B <![CDATA[cur_p1 AB 1-32 ]]> <![CDATA[cur_p2 AB 1-32 ]]> （0.6，0.54） no / 1、2 / 4A and 6C <![CDATA[cur_p1 AC 1-32 ]]> <![CDATA[cur_p2 AC 1-32 ]]> （0.38，0.46） no / 1、2 / 4B and 6A <![CDATA[cur_p1 BA 1-32 ]]> <![CDATA[cur_p2 BA 1-32 ]]> （-0.41，0.55） no / 1、2 / 4B and 6B <![CDATA[cur_p1 BB 1-32 ]]> <![CDATA[cur_p2 BB 1-32 ]]> （0.79，0.86） no / 1、2 / 4B and 6C <![CDATA[cur_p1 BC 1-32 ]]> <![CDATA[cur_p2 BC 1-32 ]]> （0.48，0.43） no / 1、2 / 4C and 6A <![CDATA[cur_p1 AA 1-32 ]]> <![CDATA[cur_p2 AA 1-32 ]]> （0.55，-0.4） no / 1、2 / 4C and 6B <![CDATA[cur_p1 AA 1-32 ]]> <![CDATA[cur_p2 AA 1-32 ]]> （-0.56，-0.34） no / 1、2 / 4C and 6C <![CDATA[cur_p1 AA 1-32 ]]> <![CDATA[cur_p2 AA 1-32 ]]> （0.88，0.96） no / 1、2 /

[0188] Based on Table 3, if phase A is determined to be the faulty phase, and the selected interval correlation pair array is empty, then out-of-area fault screening is performed to obtain the out-of-area correlation pair array:

[0189] (0.92, 0.81), (0.83, 0.75), (0.93, -0.86), (0.94, -0.77), (0.9, -0.96)

[0190] To satisfy the relevant segments and conditions, it is necessary to take the opposite of a specific value of the original correlation pair.

[0191] The final inter-interval correlation array is as follows:

[0192] (0.92, 0.81), (0.83, 0.75), (0.93, 0.86), (0.94, 0.77), (0.9, 0.96)

[0193] Sort the array based on the relevance of elements outside the region. The sorting result is as follows:

[0194] (0.9, 0.96), (0.93, 0.86), (0.92, 0.81), (0.94, 0.77), (0.83, 0.75)

[0195] After sorting the correlation pairs outside the designated area, the first correlation pair in the correlation pair array is (0.9, 0.96), which corresponds to two sub-triggers, triggering device 4A and triggering device 6A. When using the double-ended traveling wave method for location, the location traveling wave between triggering device 4A and triggering device 6A is used for calculation. If the location result of the double-ended traveling wave between triggering device 4A and triggering device 6A indicates that the located fault location is closer to triggering device 4A, then the fault is determined to occur in the area outside triggering device 4A.

[0196] It should be noted that when the fault occurs outside the area, although the method of this invention cannot achieve precise fault location, it can still determine which triggering device the fault point is in. The inspector only needs to check near the triggering device, which narrows the inspection range of the fault point, but still achieves the purpose of automatic fault selection and location.

[0197] Example 4

[0198] Based on the same inventive concept, this application also provides an automatic fault location and fault selection system for power transmission and distribution networks. The solution provided by this automatic fault location and fault selection system for power transmission and distribution networks is similar to the solution described in Embodiment 1. Therefore, the specific limitations of one or more embodiments of the automatic fault location and fault selection system for power transmission and distribution networks provided below can be found in the limitations of the method in Embodiment 1, and will not be repeated here.

[0199] In one exemplary embodiment, an automatic fault location and fault selection system for power transmission and distribution networks is provided, comprising:

[0200] Multiple triggering devices are installed at various points along the line. At each point, triggering device A, triggering device B, and triggering device C are respectively installed on phase lines A, B, and C. The multiple triggering devices are grouped as follows:

[0201] Determine the time when the fault current first arrives at each triggering device on the line, and determine the location of the triggering device that arrives earliest as the first point in the entire line;

[0202] Based on the identified first point, the points along the route are grouped into upstream and downstream sections; among them,

[0203] The upstream portion includes all points from the first point towards the power supply side;

[0204] The downstream portion includes all other points along the line excluding the upstream portion;

[0205] Based on the first point, the points along the route are grouped into four parts, namely:

[0206] The first section includes the points through which the current flows from the power supply side to the first point in the upstream section;

[0207] The second section includes the points in the upstream portion excluding the points in the first section;

[0208] The third section includes the points through which the current flows after passing the first point in the downstream section;

[0209] The fourth section includes the points in the downstream portion excluding the points in the third section;

[0210] The correlation calculation module is used to calculate the phase correlation of current pairs between the three triggering devices A, B, and C at the first point and the three triggering devices A, B, and C at other points, denoted as cur_p1. ij 1-mn This is used to determine whether the currents are in phase; and to calculate the positional correlation of the current pairs between the three triggering devices A, B, and C at the first point and the three triggering devices A, B, and C at other points, denoted as cur_p2. ij 1-mn This is used to determine whether the fault occurred between or outside the two triggering devices;

[0211] Where i represents the three phases, i = A, B, C; j represents the three phases, j = A, B, C; m represents the segment, m = 1, 2, 3, 4; n represents the nth point in the segment, n = 1, 2, ..., N;

[0212] When calculating phase correlation, the current pair used for calculation is the current waveform of the corresponding trigger device for two cycles, from two cycles before the fault occurrence time to four cycles before the fault occurrence time.

[0213] When calculating the correlation of location points, the current pairs used for calculation are the current waveform data points 10 points after the time of the fault occurrence of the corresponding triggering device.

[0214] The fault phase determination module is used to compare the current at the triggering time of all triggering devices and take the maximum value as the maximum current value; it is also used to determine the phase where the triggering device is located as the fault phase after determining that the current value at the triggering time of any triggering device is greater than or equal to 80% of the maximum current value.

[0215] The fault area filtering module, connected to the correlation calculation module, is used to filter fault areas based on the calculation results of the correlation calculation module, including an interval fault filtering module, an external fault filtering module, and a handover judgment module.

[0216] The interval fault screening module is used to perform interval fault screening, and the method is as follows:

[0217] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the first segment satisfy condition 1 or condition 2, then it is determined that the fault occurs between the two triggering devices, and the cur_p1 of the current pair between the two triggering devices is taken. ij 1-1n and cur_p2 ij 1-1n If condition 1 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-1n cur_p2 ij 1-1n If condition 2 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-1n -cur_p2 ij 1-1n );

[0218] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the second section satisfy condition 3 or condition 4, then it is determined that the fault occurs between the two triggering devices, and the cur_p1 of the current pair between the two triggering devices is taken. ij 1-2n and cur_p2 ij 1-2n If condition 3 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-2n -cur_p2 ij 1-2n If condition 4 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-2n cur_p2 ij 1-2n );

[0219] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the third segment satisfy condition 1 or condition 2, then it is determined that the fault occurs between the two triggering devices, and the cur_p1 of the current pair between the two triggering devices is taken. ij 1-3n and cur_p2 ij 1-3n If condition 1 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-3n cur_p2ij 1-3n If condition 2 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-3n -cur_p2 ij 1-3n );

[0220] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the fourth segment satisfy condition 3 or condition 4, then it is determined that the fault occurs between the two triggering devices, and the cur_p1 of the current pair between the two triggering devices is taken. ij 1-4n and cur_p2 ij 1-4n If condition 3 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-4n -cur_p2 ij 1-4n If condition 4 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-4n cur_p2 ij 1-4n );

[0221] Condition 1: cur_p1 > 0.8, cur_p2 < -0.7, and it is a faulty phase;

[0222] Condition 2: cur_p1 < -0.8, cur_p2 > 0.7, and both are fault phases;

[0223] Condition 3: cur_p1>0.8, cur_p2>0.7, and they are faulty phases;

[0224] Condition 4: cur_p1 < -0.8, cur_p2 < -0.7, and it is a faulty phase;

[0225] Switch the judgment module to determine whether the array of correlation pairs to be sorted in the interval is empty;

[0226] The out-of-area fault screening module is used to screen out out-of-area faults when the array of correlation pairs to be sorted within an interval is empty. The method is as follows:

[0227] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the first segment satisfy condition 3 or condition 4, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 value of the current pair in these two triggering devices is taken. ij 1-1n and cur_p2 ij1-1n If condition 3 is satisfied, then the external fault correlation pair (cur_p1) is formed. ij 1-1n cur_p2 ij 1-1n If condition 4 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-1n -cur_p2 ij 1-1n );

[0228] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the second segment satisfy condition 1 or condition 2, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 value of the current pair between these two triggering devices is taken. ij 1-2n and cur_p2 ij 1-2n If condition 1 is satisfied, then the external fault correlation pair (cur_p1) is formed. ij 1-2n -cur_p2 ij 1-2n If condition 2 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-2n cur_p2 ij 1-2n );

[0229] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the third segment satisfy condition 3 or condition 4, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 of the current pair in these two triggering devices is taken. ij 1-3n and cur_p2 ij 1-3n If condition 3 is met, then the external fault correlation pair (cur_p1) is formed. ij 1-3n cur_p2 ij 1-3n If condition 4 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-3n -cur_p2 ij 1-3n );

[0230] If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the fourth segment satisfy condition 1 or condition 2, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 of the current pair in these two triggering devices is taken. ij 1-4n and cur_p2 ij 1-4n If condition 1 is satisfied, then the external fault correlation pair (cur_p1) is formed. ij 1-4n -cur_p2 ij 1-4n If condition 2 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-4n cur_p2 ij 1-4n );

[0231] After filtering out all external fault correlation pairs, the external fault correlation pairs (cur_p1) are... ij 1-1n cur_p2 ij 1 -1n (cur_p1) ij 1-3n cur_p2 ij 1-3n (cur_p1) ij 1-2n cur_p2 ij 1-2n ) and (cur_p1 ij 1-4n cur_p2 ij 1-4n Together, they form an array of out-of-area, unordered correlation pairs for fault location.

[0232] A traveling wave positioning module, connected to the fault area screening module, is used to perform traveling wave positioning based on the results of the fault area screening module, including an inter-area traveling wave positioning module and an inter-area traveling wave positioning module.

[0233] The interval traveling wave positioning module is used to, when the interval unsorted correlation pair array is not empty, first perform a positioning based on cur_p2 on the interval unsorted correlation pair array. ij Perform ascending sorting, if cur_p2 ij Equal, then based on cur_p1 ij Perform descending sorting to obtain a range-sorted array of related pairs.

[0234] After sorting the intervals into a correlation pair array, take the positioning traveling wave between the two triggering devices corresponding to the first correlation pair in the array, and use the double-ended traveling wave method to locate the fault location.

[0235] The out-of-area traveling wave positioning module is used to, when the inter-area unsorted correlation pair array is empty, first perform a positioning based on cur_p2 on the out-of-area unsorted correlation pair array. ij Perform descending sorting, if cur_p2 ij Equal, then based on cur_p1 ij Perform descending sorting to obtain the array of related pairs after sorting outside the region;

[0236] After sorting the correlation pairs outside the area, take the positioning wave between the two triggering devices corresponding to the first correlation pair in the array, and use the double-ended wave method for positioning.

[0237] Based on the dual-end traveling wave positioning results, if the located fault location is closer to a triggering device, it is determined that the fault occurs in the area outside that triggering device.

[0238] Example 5

[0239] Each module in the above system can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of the computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0240] In one exemplary embodiment, a computer device is provided, which may be a terminal. It includes:

[0241] One or more processors; memory for storing one or more programs.

[0242] When the one or more programs are executed by the one or more processors, the one or more processors perform the steps of the automatic fault selection and location method for power transmission and distribution network lines.

[0243] In one exemplary embodiment, a computer-readable storage medium is also provided, on which a computer program is stored, which, when executed by a processor, implements the steps of an automatic fault selection and location method for power transmission and distribution network lines.

[0244] In one exemplary embodiment, a computer program product is also provided, including a computer program / instructions, characterized in that, when the computer program / instructions are executed by a processor, they implement the steps of an automatic fault selection and location method for power transmission and distribution network lines.

[0245] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for automatic fault selection and location in power transmission and distribution networks, characterized in that, Includes the following steps: Determine the time when the fault current first arrives at each triggering device on the line, and designate the location of the triggering device that arrives earliest as the first point in the entire line; wherein, the triggering devices installed on each phase of the three-phase line constitute the points on that phase line. Based on the determined first point, the points on the line are first grouped into upstream and downstream sections; then, based on the first point, the points on the line are grouped into four segments. The upstream section includes all points from the first point towards the power supply side; the downstream section includes all other points on the line excluding the upstream section; the first segment includes the points in the upstream section through which the current flows from the power supply side to the first point; the second segment includes the points in the upstream section excluding the first segment; the third segment includes the points in the downstream section through which the current flows after passing the first point; and the fourth segment includes the points in the downstream section excluding the third segment. Acquire fault current waveform data recorded by triggering devices at various points on the power transmission and distribution network lines; For the triggering device at the first point, calculate the pair of currents between each of its three phases (A, B, and C) triggering devices and any other triggering device at any other point (A, B, and C). The phase correlation index is used to determine whether the pair of currents are in phase, and the location correlation index is used to determine the fault interval. Based on the current amplitude of all triggering devices at the triggering moment, the faulty phase is identified; Based on the phase correlation index, location point correlation index, and preset interval fault judgment conditions and out-of-area fault judgment conditions, combined with the identified fault phase, an interval unsorted correlation pair array or an out-of-area unsorted correlation pair array for fault location is selected. When there is an array of interval correlation pairs to be sorted, a pair of target correlation pairs is selected from the array of interval correlation pairs to be sorted according to the first preset rule, and the two triggering devices corresponding to the pair of target correlation pairs perform interval double-end traveling wave positioning. When there is only an array of out-of-area unsorted correlation pairs, a pair of target correlation pairs is selected from the array of out-of-area unsorted correlation pairs according to the second preset rule. Out-of-area double-ended traveling wave positioning is performed on the two triggering devices corresponding to the pair of target correlation pairs. Based on the positioning result, it is determined that the fault point is located in the outer area of ​​the triggering device that is closer to it.

2. The automatic fault selection and location method for power transmission and distribution network lines according to claim 1, characterized in that, Methods for calculating correlation index and location point correlation index include: The phase correlation index is calculated based on the current waveform data of the corresponding pair of currents between the two and four cycles before the fault occurs. The location point correlation index is calculated based on the current waveform data points of the corresponding pair of currents 10 times after the fault occurs.

3. The automatic fault selection and location method for power transmission and distribution network lines according to claim 1, characterized in that, Methods for identifying the faulty phase based on the current amplitude of all triggering devices at the triggering moment include: Compare the current amplitude at the triggering time of all triggering devices, and take the maximum value as the maximum current value. If the current value at the triggering time of any triggering device is greater than or equal to 80% of the maximum current value, then the phase where the triggering device is located is the faulty phase.

4. The automatic fault selection and location method for power transmission and distribution network lines according to claim 1, characterized in that, Methods for filtering out the array of unsorted correlation pairs within an interval or the array of unsorted correlation pairs outside an interval for fault location include: Define the correlation index as cur_p1 ij 1-mn The correlation index for location points is cur_p2 ij 1-mn Where i represents three phases, i = A, B, C; j represents three phases, j = A, B, C; m represents a segment, m = 1, 2, 3, 4; n represents the nth point in the segment, n = 1, 2, ..., N; Define the following four conditions: Condition 1: cur_p1 > 0.8, cur_p2 < -0.7, and it is a faulty phase; Condition 2: cur_p1 < -0.8, cur_p2 > 0.7, and both are fault phases; Condition 3: cur_p1>0.8, cur_p2>0.7, and they are faulty phases; Condition 4: cur_p1 < -0.8, cur_p2 < -0.7, and it is a faulty phase; Methods for filtering arrays based on the correlation between intervals to be sorted: If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the first segment satisfy condition 1 or condition 2, then it is determined that the fault occurs between the two triggering devices, and the cur_p1 of the current pair between the two triggering devices is taken. ij 1-1n and cur_p2 ij 1-1n If condition 1 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-1n cur_p2 ij 1-1n If condition 2 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-1n -cur_p2 ij 1-1n ); If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the second section satisfy condition 3 or condition 4, then it is determined that the fault occurs between the two triggering devices, and the cur_p1 of the current pair between the two triggering devices is taken. ij 1-2n and cur_p2 ij 1-2n If condition 3 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-2n -cur_p2 ij 1-2n If condition 4 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-2n cur_p2 ij 1-2n ); If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the third segment satisfy condition 1 or condition 2, then it is determined that the fault occurs between the two triggering devices, and the cur_p1 of the current pair between the two triggering devices is taken. ij 1-3n and cur_p2 ij 1-3n If condition 1 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-3n cur_p2 ij 1-3n If condition 2 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-3n -cur_p2 ij 1-3n ); If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the fourth segment satisfy condition 3 or condition 4, then it is determined that the fault occurs between the two triggering devices, and the cur_p1 of the current pair between the two triggering devices is taken. ij 1-4n and cur_p2 ij 1-4n If condition 3 is satisfied, then the interval fault correlation pair (cur_p1) is formed. ij 1-4n -cur_p2 ij 1-4n If condition 4 is satisfied, then the interval fault correlation pair (-cur_p1) is formed. ij 1-4n cur_p2 ij 1-4n ); After filtering out all interval fault correlation pairs, the interval fault correlation pairs (cur_p1) are... ij 1-1n cur_p2 ij 1-1n (cur_p1) ij 1-3n cur_p2 ij 1-3n (cur_p1) ij 1-2n cur_p2 ij 1-2n ) and (cur_p1 ij 1-4n cur_p2 ij 1-4n Together they form an array of unsorted correlation pairs within the interval; Methods for filtering arrays based on relevance of unsorted data outside the region: If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the first segment satisfy condition 3 or condition 4, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 value of the current pair in these two triggering devices is taken. ij 1-1n and cur_p2 ij 1-1n If condition 3 is satisfied, then the external fault correlation pair (cur_p1) is formed. ij 1-1n cur_p2 ij 1-1n If condition 4 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-1n -cur_p2 ij 1-1n ); If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the second segment satisfy condition 1 or condition 2, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 value of the current pair between these two triggering devices is taken. ij 1-2n and cur_p2 ij 1-2n If condition 1 is satisfied, then the external fault correlation pair (cur_p1) is formed. ij 1-2n -cur_p2 ij 1-2n If condition 2 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-2n cur_p2 ij 1-2n ); If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the third segment satisfy condition 3 or condition 4, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 of the current pair in these two triggering devices is taken. ij 1-3n and cur_p2 ij 1-3n If condition 3 is met, then the external fault correlation pair (cur_p1) is formed. ij 1-3n cur_p2 ij 1-3n If condition 4 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-3n -cur_p2 ij 1-3n ); If the phase correlation and position correlation of the current pair between any triggering device at the first point and any triggering device at any point in the fourth segment satisfy condition 1 or condition 2, then it is determined that the fault occurs outside of these two triggering devices, and the cur_p1 of the current pair in these two triggering devices is taken. ij 1-4n and cur_p2 ij 1-4n If condition 1 is satisfied, then the external fault correlation pair (cur_p1) is formed. ij 1-4n -cur_p2 ij 1-4n If condition 2 is satisfied, then the external fault correlation pair (-cur_p1) is formed. ij 1-4n cur_p2 ij 1-4n ); After filtering out all external fault correlation pairs, the external fault correlation pairs (cur_p1) are... ij 1-1n cur_p2 ij 1-1n (cur_p1) ij 1-3n cur_p2 ij 1-3n (cur_p1) ij 1-2n cur_p2 ij 1-2n ) and (cur_p1 ij 1-4n cur_p2 ij 1-4n Together they form an array of correlation pairs outside the region that are to be sorted.

5. The automatic fault selection and location method for power transmission and distribution network lines according to claim 1, characterized in that, According to the first preset rule, a pair of target correlation pairs are selected and double-ended traveling wave localization within the interval is performed, specifically including: For the array of correlation pairs to be sorted in the specified interval, first based on cur_p2 ij Perform ascending sorting, if cur_p2 ij Equal, then based on cur_p1 ij Perform descending sorting to obtain a range-sorted array of correlation pairs. After sorting the correlation pairs in the interval, take the positioning traveling wave between the two triggering devices corresponding to the first correlation pair in the array, and use the double-ended traveling wave method to locate the fault location.

6. The automatic fault selection and location method for power transmission and distribution network lines according to claim 1, characterized in that, According to the second preset rule, a pair of target correlation pairs are selected and out-of-area double-ended traveling wave localization is performed, specifically including: For the array of correlation pairs outside the region to be sorted, first based on cur_p2 ij Perform descending sorting, if cur_p2 ij Equal, then based on cur_p1 ij Perform descending sorting to obtain the array of related pairs after sorting outside the region; After sorting the correlation pairs outside the area, take the positioning wave between the two triggering devices corresponding to the first correlation pair in the array, and use the double-ended wave method for positioning. Based on the dual-end traveling wave positioning results, if the located fault location is closer to a triggering device, it is determined that the fault occurs in the area outside that triggering device.

7. An automatic fault selection and location system for power transmission and distribution network lines, characterized in that, include: Multiple triggering devices are set at various points on the line. At each point, triggering device A, triggering device B and triggering device C are set on phase lines A, B and C respectively. Multiple triggering devices are grouped as follows: Determine the time when the fault current first arrives at each triggering device on the line, and determine the location of the triggering device that arrives earliest as the first point in the entire line; Based on the first identified point, the points along the route are first grouped into upstream and downstream sections; Based on the first point, the points on the line are then grouped into four sections: the upstream section includes all points from the first point toward the power supply side; the downstream section includes all other points on the line excluding the upstream section; the first section includes the points in the upstream section through which the current flows from the power supply side to the first point; the second section includes the points in the upstream section excluding the first section; the third section includes the points in the downstream section through which the current flows after passing the first point; and the fourth section includes the points in the downstream section excluding the third section. The correlation calculation module is used to calculate the pair of currents between each phase triggering device of the A, B, and C phases of the triggering device at the first point and any phase triggering device of the A, B, and C phases at any other point. It is used to determine whether the pair of currents are in phase, and to determine the location point correlation index of the fault interval. The fault phase identification module identifies the fault phase based on the current amplitude of all triggering devices at the triggering time; The fault area filtering module is connected to the correlation calculation module and the fault phase judgment module. It is used to filter out the interval unsorted correlation pair array or the outside unsorted correlation pair array for fault location based on the phase correlation index, the location point correlation index, and the preset interval fault judgment conditions and outside fault judgment conditions, combined with the identified fault phase. A traveling wave positioning module, connected to the fault area screening module, is used to select a target correlation pair from the interval unsorted correlation pair array according to a first preset rule when an interval unsorted correlation pair array exists, and to perform interval double-end traveling wave positioning on the two triggering devices corresponding to the target correlation pair; and When there is only an array of out-of-area unsorted correlation pairs, a pair of target correlation pairs is selected from the array of out-of-area unsorted correlation pairs according to the second preset rule. Out-of-area double-ended traveling wave positioning is performed on the two triggering devices corresponding to the pair of target correlation pairs. Based on the positioning result, it is determined that the fault point is located in the outer area of ​​the triggering device that is closer to it.

8. A computer device, characterized in that, include: One or more processors; Memory, used to store one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors perform the steps of the automatic fault selection and location method for power transmission and distribution lines as described in any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that, When the program is executed by the processor, it implements the steps of the automatic fault selection and location method for power transmission and distribution network lines as described in any one of claims 1 to 6.

10. A computer program product comprising a computer program / instructions, characterized in that, When the computer program / instruction is executed by the processor, it implements the steps of the automatic fault selection and location method for power transmission and distribution network lines as described in any one of claims 1 to 6.

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