A line selection method for judging the fault point based on the pull-switch increment method

Abstract

The present invention discloses a line selection method for judging a fault point based on the pull-switching increment method, which relates to the technical field of fault point line selection, and includes the following steps: installing monitoring sensors on line nodes to monitor the current and voltage of the line nodes, and at the same time obtaining the topology map of the power line; analyzing the reference current and reference voltage of the line nodes during normal operation; when a fault occurs in the circuit system, calculating the current increment and voltage increment of different line nodes; based on the topology map, current increment and voltage increment, selecting the line for the fault point by the pull-switching increment method; the present invention is used to solve the problem that the existing fault point line selection technology still uses relatively small characteristic quantities as the judgment basis and does not exclude the influence of ambient temperature, resulting in a low accuracy of fault line selection.

Description

Technical Field

[0001] The present invention relates to the technical field of fault point line selection, and specifically provides a line selection method for judging fault points based on the pull-off increment method. Background Art

[0002] The fault point line selection technology refers to a technology for fault location in a power system. By analyzing parameter data such as voltage and current in the power system and combining specific algorithms and methods, the location of a fault occurring in the system is determined. During the operation of the power system, various types of faults may occur, such as short circuits, grounding faults, etc. These faults will affect the normal operation of the system. Therefore, it is necessary to locate and handle these faults in a timely and accurate manner.

[0003] Existing fault point line selection technologies usually find fault lines and fault points through the traditional sequential switching-off method and visual line patrol method. However, various protection devices for finding single-phase grounding faults mainly use relatively small characteristic quantities as criteria, so the accuracy rate is relatively low. This is a typical line selection and positioning principle based on the steady-state quantity of single-phase grounding faults, which uses the amplitude and phase relationship of zero-sequence current and zero-sequence voltage to form a criterion. The characteristic quantity of the criterion is small, and the accuracy rate is low. Moreover, the ambient temperature will also cause changes in the current, voltage on the line and the indication value of the sensor, which will also reduce the accuracy rate of line selection. For example, in the patent application with the publication number CN115128393A, a small current grounding fault line selection and identification method for fusing fault line selection results is disclosed. This solution uses relatively small characteristic quantities such as zero-sequence current as the judgment basis, and the accuracy rate is relatively low. Existing fault point line selection technologies also have problems such as using relatively small characteristic quantities as the judgment basis and not excluding the influence of ambient temperature, resulting in a relatively low accuracy rate of fault line selection. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems in the existing technology to some extent. By installing monitoring sensors on line nodes to monitor the current and voltage of the line nodes, and simultaneously obtaining the topology map of the power line, then analyzing the current reference value and voltage reference value of the line nodes during normal operation, and then analyzing the reference current and reference voltage of the line nodes based on the current reference value and voltage reference value. When a fault occurs in the circuit system, calculate the current increment and voltage increment of different line nodes, analyze the safe range of the current increment based on the normal current increment, mark it as the current safety range, and then analyze the safe range of the voltage increment based on the normal voltage increment, mark it as the voltage safety range. Finally, based on the current safety range and voltage safety range, combined with the topology map for analysis, select the line for the fault point to solve the problems that existing fault point line selection technologies also use relatively small characteristic quantities as the judgment basis and do not exclude the influence of ambient temperature, resulting in a relatively low accuracy rate of fault line selection.

[0005] To achieve the above object, in a first aspect, the present application provides a line selection method for judging a fault point based on the pull-off increment method, including the following steps:

[0006] Install monitoring sensors on the line nodes to monitor the current and voltage of the line nodes, and at the same time obtain the topology diagram of the power line;

[0007] Analyze the reference current and reference voltage of the line nodes during normal operation;

[0008] When a fault occurs in the circuit system, calculate the current increment and voltage increment of different line nodes;

[0009] Based on the topology diagram, current increment and voltage increment, select the line of the fault point by the pull-off increment method.

[0010] Further, installing monitoring sensors on the line nodes to monitor the current and voltage of the line nodes, and at the same time obtaining the topology diagram of the power line includes the following sub-steps:

[0011] Install monitoring sensors on the line nodes, and the monitoring sensors include ammeters and voltmeters;

[0012] Monitor the current and voltage of the line nodes, and name the monitored current and voltage as monitored current and monitored voltage respectively;

[0013] Obtain the topology diagram of the power line, number the line nodes in the topology diagram in ascending order of the distance from the line nodes to the power generation equipment, and represent them by the symbol L n where n is a positive integer and n is the serial number of L.

[0014] Further, analyzing the reference current and reference voltage of the line nodes during normal operation includes the following sub-steps:

[0015] Analyze the current reference value and voltage reference value of the line nodes during normal operation;

[0016] Based on the current reference value and voltage reference value, analyze and obtain the reference current and reference voltage of the line nodes.

[0017] Further, analyzing the current reference value and voltage reference value of the line nodes during normal operation includes the following sub-steps:

[0018] Obtain the temperature coefficients of the monitoring sensors, and the temperature coefficients include current coefficients and voltage coefficients;

[0019] Monitor the real-time current and real-time voltage of L n and at the same time obtain the real-time temperature;

[0020] Through the formula Vn V(0) = V n Calculate the voltage reference value through the formula V(0) = V / (SV × T), where V n (0) is the voltage reference value of L n V is the real-time voltage of L n SV is the voltage coefficient, and T is the real-time temperature; n

[0021] Calculate the current reference value through the formula I(0) = I / (SA × T), where I n (0) is the current reference value of L n n I is the real-time voltage of L n (0) is the current reference value of L n I is the real-time voltage of L n SA is the current coefficient. n

[0022] Furthermore, analyzing the reference current and reference voltage of the line node based on the current reference value and voltage reference value includes the following sub-steps:

[0023] Taking n in L as the X-axis and the current reference value as the Y-axis to establish a plane rectangular coordinate system, named the current reference distribution diagram, and inputting L n and the corresponding current reference value into the current reference distribution diagram;

[0024] Taking n in L as the X-axis and the voltage reference value as the Y-axis to establish a plane rectangular coordinate system, named the voltage reference distribution diagram, and inputting L n n and the corresponding voltage reference value into the voltage reference distribution diagram;

[0025] Performing polynomial regression on the current reference distribution diagram and the voltage reference distribution diagram respectively to obtain the current reference function and the voltage reference function;

[0026] Substituting n into the current reference function and the voltage reference function respectively to calculate the reference current and reference voltage of L n n n which are represented by the symbols IN and VN respectively.

[0027] Furthermore, when the circuit system fails, calculating the current increment and voltage increment of different line nodes includes the following sub-steps:

[0028] When the circuit system fails, obtain the real-time current and real-time voltage;

[0029] Calculate the real-time current reference value by calculating the real-time current through the calculation formula of the current reference value; calculate the real-time voltage reference value by calculating the real-time voltage through the calculation formula of the voltage reference value, which are represented by IF​​​​​​n and VF n represent;

[0030] Calculate ΔI n = IF n -IN n , where ΔI n is the current increment of L n ;

[0031] Calculate ΔV n = VF n -VN n , where ΔV n is the voltage increment of L n ;

[0032] Furthermore, based on the topological graph, current increment, and voltage increment, the fault point is selected by the pull-line increment method, which includes the following sub-steps:

[0033] Based on the analysis of the normal current increment, obtain the safe range of the current increment, marked as the current safety range;

[0034] Based on the analysis of the normal voltage increment, obtain the safe range of the voltage increment, marked as the voltage safety range;

[0035] Based on the current safety range and voltage safety range, combined with the topological graph for analysis, select the fault point.

[0036] Furthermore, based on the analysis of the normal current increment, obtaining the safe range of the current increment, marked as the current safety range, includes the following sub-steps:

[0037] Taking n in L n as the horizontal axis and the current increment as the vertical axis, establish a plane rectangular coordinate system, named the current range scatter plot;

[0038] Enter the normal current increment corresponding to L n in the historical record into the current range scatter plot, and name the coordinate points in the current range scatter plot as current increment points;

[0039] Perform polynomial regression on the current range scatter plot to obtain the current safety function, plot the current safety function in the current range scatter plot, and name the curve corresponding to the current safety function as the current safety curve;

[0040] Move the current safety curve vertically in the positive direction of the Y-axis, monitor the distribution of the current increment points, and stop moving when there are no current increment points above the current safety curve. Name the current safety curve at this time as the current safety range curve, and name the function corresponding to the current safety range curve as the current safety range function;

[0041] Substitute n into the current safety range function, and mark the calculated result as R n , and mark the range [0, R n as L n Current safety range.

[0042] Furthermore, based on the normal voltage increment analysis, obtain the safety range of voltage increment, and mark the voltage safety range, including the following sub-steps:

[0043] Taking n in L n as the horizontal axis and the voltage increment as the vertical axis, establish a plane rectangular coordinate system, named the voltage range scatter plot;

[0044] Input the corresponding normal voltage increment in the historical record of L n into the voltage range scatter plot, and name the coordinate points in the voltage range scatter plot as voltage increment points;

[0045] Perform polynomial regression on the voltage range scatter plot to obtain the voltage safety function, plot the voltage safety function in the voltage range scatter plot, and name the corresponding curve of the voltage safety function as the voltage safety curve;

[0046] Vertically move the voltage safety curve in the positive direction of the Y-axis, monitor the distribution of voltage increment points, and stop moving when there are no voltage increment points above the voltage safety curve. Name the voltage safety curve at this time as the voltage safety range curve, and name the function corresponding to the voltage safety range curve as the voltage safety range function;

[0047] Substitute n into the voltage safety range function, and mark the calculated result as E n , and mark the range [0, E n as L n Voltage safety range.

[0048] Furthermore, based on the current safety range and the voltage safety range, combined with the topology diagram for analysis, the fault line selection for the fault point includes the following sub-steps:

[0049] For the line node L n , compare the ΔI n calculated in real time with R n . If ΔI n is less than or equal to R n , then output a normal current increment signal; if ΔI n is greater than R n , then output an abnormal current increment signal;

[0050] For the line node L n , compare the ΔV n calculated in real time with E n . If ΔVn Less than or equal to E n , the output voltage increment normal signal is output; if ΔV n is greater than E n , the output voltage increment abnormal signal is output;

[0051] Mark the line nodes that have output the current increment abnormal signal or the voltage increment abnormal signal as abnormal nodes, number the abnormal nodes, and represent them by the symbol P m , where m is a positive integer and m is the serial number of P;

[0052] For any P m , the adjacent line nodes connected to P m in the topological graph through the line are named adjacent nodes, and it is detected whether there are abnormal nodes among the adjacent nodes. If there are no abnormal nodes among the adjacent nodes, the fault line signal is output; if there are abnormal nodes among the adjacent nodes, the deep line selection signal is output;

[0053] If the deep line selection signal is output, mark the adjacent abnormal nodes connected by the line in the topological graph as link nodes, obtain the maximum value of the current increment and the maximum value of the voltage increment among the link nodes, and mark them as the maximum current increment and the maximum voltage increment respectively;

[0054] Mark the abnormal nodes corresponding to the maximum current increment and the maximum voltage increment as fault nodes. If the fault nodes are the same abnormal node, the single node signal is output; if the fault nodes are different abnormal nodes, the double node signal is output;

[0055] If the single node signal is output, obtain the abnormal nodes with the second largest current increment and voltage increment among the link nodes, and mark the connection line between the fault node and them as the fault line;

[0056] If the double node signal is output, mark the connection line between the two fault nodes as the fault line.

[0057] Advantages of the present invention: By installing monitoring sensors on the line nodes, the current and voltage of the line nodes are monitored, and at the same time, the topological graph of the power line is obtained. Then, the current reference value and voltage reference value of the line nodes during normal operation are analyzed, and then the reference current and reference voltage of the line nodes are obtained based on the current reference value and voltage reference value. The advantage is that the present invention uses the incremental method for judgment. Since the ambient temperature will affect the current and voltage of the line and the indication value of the sensor, and the historical data cannot unify the ambient temperature, the reference current and reference voltage corresponding to each line node are analyzed to remove the influence of the ambient temperature, providing a reliable data basis for subsequent analysis and improving the accuracy and effectiveness of fault line selection;

[0058] When a fault occurs in the circuit system, the present invention calculates the current increment and voltage increment of different line nodes, analyzes the normal current increment to obtain the safe range of the current increment, marked as the current safety range, then analyzes the normal voltage increment to obtain the safe range of the voltage increment, marked as the voltage safety range, and finally analyzes based on the current safety range and voltage safety range, combines with the topology diagram to select the fault line. The advantage is that for each line node, the safe ranges of its current increment and voltage increment are different, and a fault in one line may cause abnormal changes in the increments of multiple adjacent lines. At this time, more accurate judgment is required instead of determining all line nodes exceeding the safe range as fault lines, which improves the accuracy and rationality of fault line selection. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 is the flowchart of the steps of the method of the present invention;

[0060] Figure 2 is the schematic diagram of the topology diagram of the present invention;

[0061] Figure 3 is the schematic diagram of the current reference distribution diagram of the present invention;

[0062] Figure 4 is the schematic diagram of the current range scatter plot of the present invention;

[0063] Figure 5 is the schematic diagram of the current safety range curve of the present invention;

[0064] Figure 6 is the schematic diagram of the abnormal node of the present invention;

[0065] Figure 7 is the structural schematic diagram of the electronic device of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0066] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0067] Embodiment 1, please refer to Figure 1 as shown, the present application provides a line selection method for judging a fault point based on the pull-off increment method, including the following steps:

[0068] Step S1, install monitoring sensors on the line nodes to monitor the current and voltage of the line nodes, and at the same time obtain the topology diagram of the power line; Step S1 includes the following sub-steps:

[0069] Step S101, install monitoring sensors on the line nodes, and the monitoring sensors include ammeters and voltmeters;

[0070] Step S102, monitor the current and voltage of the line nodes, and name the monitored current and voltage as monitored current and monitored voltage respectively;

[0071] Please refer to Figure 2 As shown, Step S103, obtain the topology diagram of the power line, number the line nodes in the topology diagram in ascending order of the distance from the line nodes to the power generation equipment, and represent them by the symbol L n where n is a positive integer and n is the serial number of L;

[0072] In specific implementation, both the ammeter and the voltmeter adopt existing current-voltage meters. The monitored current is 3000.42 A and the monitored voltage is 500.067 kV. The obtained topology diagram is as shown Figure 2 The numbering L of the line nodes n is also marked Figure 2 in it.

[0073] Step S2, analyze the reference current and reference voltage of the line nodes during normal operation; Step S2 includes the following sub-steps:

[0074] Step S201, analyze the current reference value and voltage reference value of the line nodes during normal operation;

[0075] Step S201 includes the following sub-steps:

[0076] Step S2011, obtain the temperature coefficients of the monitoring sensors, and the temperature coefficients include current coefficient and voltage coefficient;

[0077] Step S2012, monitor the real-time current and real-time voltage of L n and at the same time obtain the real-time temperature;

[0078] Step S2013, calculate the voltage reference value through the formula V n (0) = V n / (SV × T), where V n (0) is the voltage reference value of L n , V n is the real-time voltage of L n , SV is the voltage coefficient, and T is the real-time temperature;

[0079] Step S2014, calculate the current reference value through the formula I n (0) = I n / (SA × T), where I n (0) is the current reference value of L n , I n is the real-time voltage of L n , SA is the current coefficient;

[0080] In specific implementation, the temperature coefficient is the original factory parameter of the ammeter and the voltmeter, which is an inherent value. The obtained voltage coefficient is 2 V / ℃, converted to kV is 0.002 kV / ℃, and the current coefficient is 1.5 mA / ℃, converted to A is 0.015 A / ℃; for the line node L1, at this time n = 1, the obtained real-time current is 3000.42 A, the real-time voltage is 500.067 kV, and the real-time temperature is 34℃. Through calculation, the voltage reference value V1(0) = 499.999 kV and the current reference value I1(0) = 2999.91 A are obtained;

[0081] Step S202, analyze the reference current and reference voltage of the line node based on the current reference value and the voltage reference value;

[0082] Step S202 includes the following sub-steps:

[0083] Please refer to Figure 3 shown. Step S2021, take n in L n as the X-axis and the current reference value as the Y-axis to establish a plane rectangular coordinate system, named the current reference distribution diagram, and input L n and the corresponding current reference value into the current reference distribution diagram;

[0084] Step S2022, take n in L n as the X-axis and the voltage reference value as the Y-axis to establish a plane rectangular coordinate system, named the voltage reference distribution diagram, and input L n and the corresponding voltage reference value into the voltage reference distribution diagram;

[0085] Step S2023, perform polynomial regression on the current reference distribution diagram and the voltage reference distribution diagram respectively to obtain the current reference function and the voltage reference function;

[0086] Step S2024, substitute n into the current reference function and the voltage reference function respectively, calculate the reference current and reference voltage of L n , and represent them by the symbols IN n and VN n respectively;

[0087] In specific implementation, the constructed current reference distribution diagram is as shown in Figure 3As shown, the current reference function obtained by polynomial regression is YI = -0.00003×X 2 -0.0061×X + 3000.1, where YI is the current reference value and X is n in L n ; Similarly, the voltage reference function is analyzed to be YV = 0.000005×X 2 -0.0022×X + 500.08, where YV is the voltage reference value; Since there are 48 line nodes in total, the specific reference current and reference voltage of each line node are not shown in this embodiment. Only by substituting the corresponding n in L n into the current reference function and the voltage reference function can the corresponding reference current and reference voltage be obtained.

[0088] Step S3, when a fault occurs in the circuit system, calculate the current increment and voltage increment of different line nodes; Step S3 includes the following sub-steps:

[0089] Step S301, when a fault occurs in the circuit system, obtain the real-time current and real-time voltage;

[0090] Step S302, calculate the real-time current reference value by calculating the real-time current through the calculation formula of the current reference value; calculate the real-time voltage reference value by calculating the real-time voltage through the calculation formula of the voltage reference value, and represent them by IF n and VF n respectively;

[0091] Step S303, calculate ΔI n = IF n - IN n , where ΔI n is the current increment of L n ;

[0092] Step S304, calculate ΔV n = VF n - VN n , where ΔV n is the voltage increment of L n ;

[0093] In a specific implementation, taking L1 as an example, at this time n = 1, the monitored real-time current IF1 is 3372.46 A, and the real-time voltage VF1 is 521.745 kV. Substitute X = 1 into YI = -0.00003×X 2 -0.0061×X + 3000.1 and YV = 0.000005×X 2 -0.0022×X + 500.08, and solve to get YI = IN1 as 3000.0938 A, YV = VN nIt is 500.077805. By calculation, ΔI1 = 3372.46 - 3000.0938 = 372.3662, and ΔV1 = 521.745 - 500.077805 = 21.667195.

[0094] Step S4: Based on the topological graph, current increment, and voltage increment, select the fault line through the pull - out increment method; Step S4 includes the following sub - steps:

[0095] Step S401: Analyze the normal current increment to obtain the safe range of the current increment, marked as the current safety range;

[0096] Step S401 includes the following sub - steps:

[0097] Please refer to Figure 4 As shown, in Step S4011, take n in L n as the horizontal axis and the current increment as the vertical axis to establish a plane rectangular coordinate system, named the current range scatter plot;

[0098] Step S4012: Enter the normal current increment corresponding to L in the historical record into the current range scatter plot, and name the coordinate points in the current range scatter plot as current increment points; n Step S4013: Conduct polynomial regression on the current range scatter plot to obtain the current safety function, plot the current safety function in the current range scatter plot, and name the corresponding curve of the current safety function as the current safety curve;

[0099] Please refer to

[0100] As shown, in Step S4014, move the current safety curve vertically in the positive direction of the Y - axis, monitor the distribution of current increment points, and stop moving when there are no current increment points above the current safety curve. Name the current safety curve at this time as the current safety range curve, and name the function corresponding to the current safety range curve as the current safety range function; Figure 5 Step S4015: Substitute n into the current safety range function, mark the calculated result as R

[0101] n n n n , and mark the range [0, R n as the L n

[0102] Figure 4 In a specific implementation, the constructed current range scatter plot is as 2 shown. The current safety function obtained through polynomial regression is YSI = 0.0004×X 2 +0.0355×X + 101.44, where YSI is the current increment. The obtained current safety range curve after moving is as Figure 5As shown, the current safety range function is obtained as YSI = 0.0004×X 2 + 0.0355×X + 103.7214. Taking the line node L1 as an example, at this time n = 1, substituting X = 1 into YSI = 0.0004×X 2 + 0.0355×X + 103.7214, calculating to obtain R1 = 103.7573. Therefore, the current safety range of L1 is [0, 103.7573];

[0103] Step S402, based on the analysis of the normal voltage increment, obtain the safety range of the voltage increment, marked as the voltage safety range;

[0104] Step S402 includes the following sub - steps:

[0105] Step S4021, taking n in L n as the horizontal axis and the voltage increment as the vertical axis to establish a plane rectangular coordinate system, named the voltage range scatter plot;

[0106] Step S4022, input the normal voltage increments corresponding to L n in the historical records into the voltage range scatter plot, and name the coordinate points in the voltage range scatter plot as voltage increment points;

[0107] Step S4023, perform polynomial regression on the voltage range scatter plot to obtain the voltage safety function, plot the voltage safety function in the voltage range scatter plot, and name the corresponding curve of the voltage safety function as the voltage safety curve;

[0108] Step S4024, move the voltage safety curve vertically in the positive direction of the Y - axis, monitor the distribution of the voltage increment points, and stop moving when there are no voltage increment points above the voltage safety curve. Name the voltage safety curve at this time as the voltage safety range curve, and name the function corresponding to the voltage safety range curve as the voltage safety range function;

[0109] Step S4025, substitute n into the voltage safety range function, mark the calculated result as E n and mark the range [0, E n as the voltage safety range of L n ;

[0110] In a specific implementation, the analysis process of the voltage safety range function is exactly the same as that of the current safety range function. Therefore, in this embodiment, no specific description will be given here, only the final result is shown. Referring to the analysis process of the current safety range function, the voltage safety range function is obtained as YVI = - 0.00008×X 2-0.0082×X + 24.3427, where YVI is the voltage increment. Taking L1 as an example, at this time n = 1, and E1 = 24.33442 is calculated, and the voltage safety range of L1 is [0, 24.33442];

[0111] Step S403: Based on the current safety range and the voltage safety range, analyze in combination with the topology diagram to select the fault line;

[0112] Step S403 includes the following sub-steps:

[0113] Step S4031: For the line node L n , compare the ΔI n obtained by real-time calculation with R n . If ΔI n is less than or equal to R n , output a normal current increment signal; if ΔI n is greater than R n , output an abnormal current increment signal;

[0114] Step S4032: For the line node L n , compare the ΔV n obtained by real-time calculation with E n . If ΔV n is less than or equal to E n , output a normal voltage increment signal; if ΔV n is greater than E n , output an abnormal voltage increment signal;

[0115] Step S4033: Mark the line node that outputs an abnormal current increment signal or an abnormal voltage increment signal as an abnormal node, number the abnormal nodes, and represent them by the symbol P m , where m is a positive integer and m is the serial number of P;

[0116] In a specific implementation, taking the line node L1 as an example, in this embodiment, ΔI1 = 372.3662, ΔV1 = 21.667195 are calculated, while R1 = 103.7573 and E1 = 24.33442. By comparison, ΔI1 is greater than R1, and an abnormal current increment signal is output. ΔV1 is less than E1, and a normal voltage increment signal is output. Since an abnormal current increment signal is output for L1, the line node L1 is marked as an abnormal node. The numbers of line nodes are usually sorted in ascending order of n in L n , and the abnormal node L1 is marked as P1. After analyzing all L n , the abnormal nodes P1 to P 12 are obtained;

[0117] Please refer toFigure 6 As shown in Figure 6 , in step S4034, for any P m , name the adjacent line nodes connected to P in the topology diagram as adjacent nodes, and detect whether there are abnormal nodes among the adjacent nodes. If there are no abnormal nodes among the adjacent nodes, output a fault line signal; if there are abnormal nodes among the adjacent nodes, output a deep line selection signal; m

[0118] In step S4035, if a deep line selection signal is output, mark the adjacent abnormal nodes connected by lines in the topology diagram as link nodes, and obtain the maximum value of the current increment and the maximum value of the voltage increment among the link nodes, and mark them as the maximum current increment and the maximum voltage increment respectively;

[0119] In specific implementation, abnormal nodes are as shown in Figure 6 Figure 6 Figure 6 In Figure 6 , L1 and L2 are connected by a line. For L1, L2 is the adjacent node of L1. The adjacent node of P1 is only L2, and L2 is not an abnormal node. Therefore, a fault line selection signal is output, and P1 is marked as the fault point. Since all the line nodes adjacent to P1 are normal nodes, it indicates that the power lines connected between them are all fault-free. At this time, it can only be that the line node itself has a fault; at the same time, in Figure 6 Figure 6 In Figure 6 , P2, P3, P5, P7, P8, P9, P 10 , P 11 and P 12 as well as P

[0120] are link nodes, and P4 and P6 also form link nodes. For P2, there are P3 and P5 among the adjacent nodes. Therefore, a deep line selection signal is output. Among the link nodes where P2 is located, the maximum current increment and the maximum voltage increment are 287.463 A and 28.4635 kV respectively;

[0121] In step S4036, mark the abnormal nodes corresponding to the maximum current increment and the maximum voltage increment as fault nodes. If the fault nodes are the same abnormal node, output a single node signal; if the fault nodes are different abnormal nodes, output a double node signal;

[0122] In step S4037, if a single node signal is output, obtain the abnormal nodes with the second largest current increment and voltage increment among the link nodes, and mark the connection line between the fault node and them as the fault line;

[0123] In step S4038, if a double node signal is output, mark the connection line between the two fault nodes as the fault line;

[0123] In specific implementation, it is found that the fault node corresponding to the maximum current increment is P8, and the fault node corresponding to the maximum voltage increment is P 10, the faulty nodes are not the same node, so a dual-node signal is output, and the connection line between the two faulty nodes is marked as a faulty line, that is, the power line between P8 to P9 and then to P 10 is marked as a faulty line.

[0124] Example 2, please refer to Figure 7 as shown in Figure 7 illustrates a schematic structural diagram of an electronic device. The electronic device may include: a processor, a communication interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory complete mutual communication through the communication bus. The memory stores computer-readable instructions, and the processor can call the instructions in the memory. When the computer-readable instructions are executed by the processor, the steps in a line selection method for judging a fault point based on the pull-switch increment method are run to implement the following functions: installing monitoring sensors on the line nodes to monitor the current and voltage of the line nodes, and at the same time obtaining the topology map of the power line; analyzing the reference current and reference voltage of the line nodes during normal operation; when a fault occurs in the circuit system, calculating the current increment and voltage increment of different line nodes; based on the topology map, current increment, and voltage increment, selecting the line for the fault point through the pull-switch increment method.

[0125] In addition, when the logical instructions in the above-mentioned memory are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of this application. And the aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0126] Embodiment 3. The present application further provides a computer program product. The computer program product includes a computer program stored on a computer-readable storage medium. The computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute a line selection method for judging a fault point provided by each of the above methods. The method includes: installing monitoring sensors on line nodes to monitor the current and voltage of the line nodes, and simultaneously obtaining a topology diagram of the power line; analyzing the reference current and reference voltage of the line nodes during normal operation; when a fault occurs in the circuit system, calculating the current increment and voltage increment of different line nodes; and selecting the fault line by the pull-off increment method based on the topology diagram, current increment, and voltage increment.

[0127] Embodiment 4. The present application further provides a computer-readable storage medium. The present application provides a storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps in a line selection method for judging a fault point based on the pull-off increment method as described above are run to achieve the following functions: installing monitoring sensors on line nodes to monitor the current and voltage of the line nodes, and simultaneously obtaining a topology diagram of the power line; analyzing the reference current and reference voltage of the line nodes during normal operation; when a fault occurs in the circuit system, calculating the current increment and voltage increment of different line nodes; and selecting the fault line by the pull-off increment method based on the topology diagram, current increment, and voltage increment.

[0128] Through the description of the above embodiments, the embodiments of the present invention can be provided as a method, a system, or a computer program product. Based on such an understanding, the above technical solution, in essence, or the part that contributes to the prior art can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disc, etc., and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0129] In the embodiments provided by the present application, it should be understood that the disclosed system or method can be implemented in other ways. The above-described embodiments are merely illustrative. For example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation. For another example, multiple modules or units can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection can be through some communication interfaces. The indirect coupling or communication connection of systems, modules, and units can be in an electrical, mechanical, or other form.

[0130] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A line selection method for judging the fault point based on the pull - off increment method, characterized in that, It includes the following steps: Install monitoring sensors on the line nodes to monitor the current and voltage of the line nodes, and at the same time obtain the topology diagram of the power line; number the line nodes in the topology diagram in ascending order of the distance from the line nodes to the power generation equipment, and represent them by the symbol L n where n is a positive integer and n is the serial number of L; Analyze the reference current and reference voltage of the line nodes during normal operation; When a fault occurs in the circuit system, calculate the current increment and voltage increment of different line nodes; Based on the topology diagram, current increment, and voltage increment, select the fault point by the pull-off increment method; Analyzing the reference current and reference voltage of the line nodes during normal operation includes the following sub-steps: Analyze the current reference value and voltage reference value of the line nodes during normal operation; Based on the current reference value and voltage reference value, analyze and obtain the reference current and reference voltage of the line nodes; Based on the current reference value and voltage reference value, analyze and obtain the reference current and reference voltage of the line nodes includes the following sub-steps: With L n Take n in it as the X-axis and the current reference value as the Y-axis to establish a plane rectangular coordinate system, named the current reference distribution diagram, and input L n and the corresponding current reference values into the current reference distribution diagram; With L n Taking n in n as the X-axis and the voltage reference value as the Y-axis to establish a plane rectangular coordinate system, named the voltage reference distribution diagram, and inputting L n and the corresponding voltage reference values into the voltage reference distribution diagram; Perform polynomial regression on the current reference distribution diagram and voltage reference distribution diagram respectively to obtain the current reference function and voltage reference function; Substitute \(n\) into the current reference function and the voltage reference function respectively, and calculate to obtain the reference current and reference voltage of \(L\), which are represented by the symbols \(I_N\) and \(V_N\) respectively. n and n \(V_N\) n respectively.

2. The line selection method for judging the fault point based on the pull-switch incremental method according to claim 1, characterized in that Install monitoring sensors on the line nodes to monitor the current and voltage of the line nodes, and at the same time obtain the topology diagram of the power line includes the following sub-steps: Install monitoring sensors on the line nodes, and the monitoring sensors include ammeters and voltmeters; Monitor the current and voltage of the line nodes, and name the monitored current and voltage as monitored current and monitored voltage respectively.

3. The line selection method for judging the fault point based on the pull-switch increment method according to claim 2, wherein Analyzing the current reference value and voltage reference value of the line nodes during normal operation includes the following sub-steps: Obtain the temperature coefficients of the monitoring sensors, and the temperature coefficients include current coefficients and voltage coefficients; Monitor L n for its real-time current and real-time voltage, and simultaneously obtain the real-time temperature; Calculate the voltage reference value through the formula V n (0)=V n / (SV×T), where V n (0) is the voltage reference value of L n , V n is the real-time voltage of L n , SV is the voltage coefficient, and T is the real-time temperature; Through formula I n (0)=I n / (SA×T) to calculate the current reference value, where I n (0) is the current reference value of L n , I n is the real-time voltage of L n , and SA is the current coefficient.

4. The line selection method for judging the fault point based on the pull-switch increment method according to claim 3, characterized in that When a fault occurs in the circuit system, calculating the current increment and voltage increment of different line nodes includes the following sub-steps: When a fault occurs in the circuit system, obtain the real-time current and real-time voltage; Calculate the real-time current through the calculation formula of the current reference value to obtain the real-time current reference value; calculate the real-time voltage through the calculation formula of the voltage reference value to obtain the real-time voltage reference value, and represent them through IF n and VF n respectively. Calculate ΔI n =IF n -IN n , where ΔI n is the current increment of L n . Calculate ΔV n = VF n - VN n , where ΔV n is the voltage increment of L n .

5. The line selection method for judging the fault point based on the pull-switch incremental method according to claim 4, wherein Based on the topology diagram, current increment, and voltage increment, selecting the fault point by the pull-off increment method includes the following sub-steps: Based on the normal current increment, analyze and obtain the safe range of the current increment, marked as the current safety range; Based on the normal voltage increment, analyze and obtain the safe range of the voltage increment, marked as the voltage safety range; Based on the current safety range and voltage safety range, combined with the topology diagram for analysis, select the fault point.

6. The line selection method for judging the fault point based on the pull-switch increment method according to claim 5, characterized in that, Based on the normal current increment, analyze and obtain the safe range of the current increment, marked as the current safety range includes the following sub-steps: Taking n in L n as the horizontal axis and the current increment as the vertical axis, a plane rectangular coordinate system is established and named the current range scatter plot; Enter the normal current increment corresponding to L in the historical record into the current range scatter plot, and name the coordinate points in the current range scatter plot as current increment points; n Enter the normal current increment corresponding to L in the historical record into the current range scatter plot, and name the coordinate points in the current range scatter plot as current increment points; Perform polynomial regression on the current range scatter plot to obtain the current safety function, draw the current safety function on the current range scatter plot, and name the curve corresponding to the current safety function as the current safety curve; Vertically move the current safety curve in the positive direction of the Y-axis, monitor the distribution of the current increment points, and stop moving when there are no current increment points above the current safety curve. Name the current safety curve at this time as the current safety range curve, and name the function corresponding to the current safety range curve as the current safety range function; Substitute n into the function of the current safety range, and mark the calculated result as R n , and mark the range [0, R n as L n Current safety range.

7. A line selection method for judging a fault point based on the pull-switch incremental method according to claim 6, characterized in that Based on the normal voltage increment, analyze and obtain the safe range of the voltage increment, marked as the voltage safety range includes the following sub-steps: Taking n in L n as the horizontal axis and the voltage increment as the vertical axis, a plane rectangular coordinate system is established and named the voltage range scatter plot; Enter the normal voltage increment corresponding to L in the historical record into the voltage range scatter plot, and name the coordinate points in the voltage range scatter plot as voltage increment points; n Enter the normal voltage increment corresponding to L in the historical record into the voltage range scatter plot, and name the coordinate points in the voltage range scatter plot as voltage increment points; Perform polynomial regression on the voltage range scatter plot to obtain the voltage safety function, draw the voltage safety function on the voltage range scatter plot, and name the curve corresponding to the voltage safety function as the voltage safety curve; Vertically move the voltage safety curve in the positive direction of the Y-axis, monitor the distribution of voltage increment points, and stop moving when there are no voltage increment points above the voltage safety curve. Name the voltage safety curve at this time as the voltage safety range curve, and name the function corresponding to the voltage safety range curve as the voltage safety range function; Substitute \(n\) into the voltage safety range function, and mark the calculated result as \(E\). n , and mark the range \([0, E\) n as \(L\). n Voltage safety range.

8. A line selection method for judging a fault point based on the pull-switch incremental method according to claim 7, characterized in that Based on the current safety range and the voltage safety range, analyze in combination with the topology diagram. The line selection for the fault point includes the following sub-steps: For line node L n , compare the ΔI obtained by real-time calculation n with R n . If ΔI n is less than or equal to R n , then output a normal signal for the current increment; If ΔI n is greater than R n , an abnormal signal of output current increment is output; For line node L n , compare the ΔV n calculated in real time with E n . If ΔV n is less than or equal to E n , output a normal voltage increment signal; if ΔV n is greater than E n , output an abnormal voltage increment signal; Mark the line node that outputs the abnormal current increment signal or the abnormal voltage increment signal as an abnormal node, number the abnormal nodes, and use the symbol P ｍ to represent, where m is a positive integer and m is the serial number of P; For any P m , the adjacent line nodes connected to P m in the topological graph through lines are named adjacent nodes, and it is detected whether there are abnormal nodes among the adjacent nodes. If there are no abnormal nodes among the adjacent nodes, a fault line signal is output; if there are abnormal nodes among the adjacent nodes, a deep line selection signal is output. If the deep line selection signal is output, mark the adjacent abnormal nodes connected by lines in the topology diagram as connection nodes, and obtain the maximum current increment and the maximum voltage increment among the connection nodes, and mark them as the maximum current increment and the maximum voltage increment respectively; Mark the abnormal nodes corresponding to the maximum current increment and the maximum voltage increment as fault nodes. If the fault nodes are the same abnormal node, output a single-node signal; if the fault nodes are different abnormal nodes, output a double-node signal; If a single-node signal is output, obtain the abnormal nodes with the second largest current increment and voltage increment among the connection nodes, and mark the connection line between the fault node and them as the fault line; If a double-node signal is output, mark the connection line between the two fault nodes as the fault line.

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