Traveling wave fault location improvement method for power distribution network fault location analysis

Abstract

The invention discloses a traveling wave fault location improvement method for power distribution network fault location analysis, relates to the technical field of power distribution networks, and solves the problems that a traditional single wave velocity model causes location deviation, and particularly, false fault points are easily generated at the joint of a cable and an overhead line due to refraction and reflection. And calculating an amplitude difference mean value under different translation amounts, automatically identifying an optimal time alignment point, and locking an association time difference t1. According to the process, time errors caused by signal distortion, asynchronous sampling and the like can be effectively corrected, the time difference precision is improved from the microsecond level to the nanosecond level, a foundation is laid for follow-up precise positioning, a plurality of correlation points are randomly selected in a locked range interval, a corrected waveform is constructed based on the attenuation proportion and repeated verification is carried out, and the time difference precision is improved. Screening an optimal solution through a feature mean value minimization algorithm; the mechanism can effectively inhibit the error of a single measuring point, and improves the robustness of a positioning result through the statistical average effect.

Description

Technical Field

[0001] The present invention relates to the technical field of distribution networks, and in particular to an improved traveling wave ranging method for fault location analysis in distribution networks. Background Art

[0002] As the "last mile" connecting the power system to users, the safe and stable operation of the distribution network directly affects power supply reliability and user experience. However, the distribution network has complex topologies (such as radial, ring, and multi-branch), diverse line types (a mix of overhead lines and cables), and frequent fault types (especially single-phase grounding and high-resistance faults), making fault location difficult. Traditional fault location methods such as impedance and signal injection are affected by factors such as line parameter variations and grounding resistance uncertainty, resulting in low positioning accuracy (often with errors of hundreds of meters), making it difficult to meet the needs of rapid power restoration in smart distribution networks. Traveling wave ranging technology has become a research hotspot for distribution network fault location due to its advantages of high positioning accuracy and fast response speed. Its core principle is to calculate the fault point location by using the propagation characteristics of transient traveling waves generated by the fault in the line (such as propagation time and waveform characteristics). The wave velocity difference between overhead lines and cables is significant. The traditional single wave velocity model leads to positioning errors, especially at the cable-overhead line connection, which is prone to false fault points due to refraction and reflection. Traditional two-terminal ranging relies on high-precision clock synchronization (nanosecond level), but distributed monitoring nodes in distribution networks often suffer from synchronization deviations due to hardware cost limitations or communication delays, leading to time difference calculation errors. Summary of the Invention

[0003] In response to the shortcomings of the existing technology, the present invention provides an improved traveling wave ranging method for distribution network fault location analysis, which solves the problem of positioning deviation caused by the traditional single wave velocity model, especially the problem of pseudo fault points easily generated by refraction and reflection at the cable-overhead line connection.

[0004] To achieve the above objectives, the present invention is implemented through the following technical solutions: an improved traveling wave ranging method for fault location analysis in distribution network, comprising the following steps: Step 1: Confirm the time of the transient traveling wave signal received by the monitoring nodes on both sides of the distribution network transmission line, and confirm and calibrate the line range where the fault point is located based on the confirmed time difference. The specific method is as follows: Based on the generated transient traveling wave signal, determining the receiving times T1 and T2 associated with the monitoring nodes on both sides of the corresponding transmission line receiving such transient traveling wave signal, where T1 and T2 represent different receiving times associated with different monitoring nodes; Use: Ct = |T1-T2| to determine the time difference Ct between the two groups of receiving times. Based on the set transmission speed v, determine the value difference of the transmission line segments on both sides, and the value difference = Ct × v, where v is a preset value; From the receiving times T1 and T2, select the minimum value and record the monitoring node associated with the minimum value as the low node. Then record the other set of monitoring nodes as the high node. Randomly select a set of line nodes from the transmission line and record the line length L1 from the line node to the low node. Then record the line length L2 from the line node to the high node. By adjusting the line node positions, ensure that (L2 - L1) = the value difference. Based on the determined line node, with this line node as the center point, confirm left and right to lock the line range where a group of fault points are located; Step 2: Based on the signal waveforms associated with the transient traveling wave signals received by the monitoring nodes on both sides, the two sets of signal waveforms are synchronously verified. From the synchronous verification process, the optimal verification process is locked, and the associated time difference is locked from the optimal verification process. The specific method is as follows: The signal waveforms associated with the transient traveling wave signals associated with the monitoring nodes on both sides are confirmed, and the two confirmed signal waveforms are checked for overlap. The two signal waveforms are placed in the same two-dimensional plane, with the horizontal coordinate in the two-dimensional plane being the timeline and the vertical coordinate axis being the amplitude. The two signal waveforms are controlled to translate left and right, and in the translation control process, the amplitude difference generated when the two signal waveforms are at the same moment is recorded, and the amplitude difference is ≥0. The confirmed amplitude differences are averaged to confirm the characteristic mean associated with the corresponding translation process. Confirm different feature means associated with different translation processes, select a minimum value from the confirmed different feature means, and record the translation process associated with the minimum value as the optimal verification process; Confirming that the time difference associated between the starting points of the two groups of signal waveforms in the optimal verification process is ≥ 0, and using the determined time difference as the determined associated time difference; Step 3: Based on the determined associated time difference and line range, recheck the time difference associated with the monitoring nodes on both sides. Based on the specific verification process, confirm the exact location of the fault point. The specific method is as follows: Based on the confirmed receiving times T1 and T2 and the associated time difference, the receiving times associated with the monitoring nodes on both sides are readjusted to Z1 and Z2; Based on the adjusted Z1 and Z2, the line nodes are recalibrated in the transmission line using the method for re-determining the line nodes in step 1. The nodes are recorded as sub-nodes, and the sub-nodes are identified to determine whether they are within the line range. If so, the location of the sub-node is recorded as the exact location of the fault point and displayed. If not, the subsequent steps are performed to re-confirm the exact location of the fault point. Step 4: Randomly select a correlation point within the line range, and confirm the attenuation ratio based on the selected correlation point and the specific line lengths of the lines on both sides. Then, based on the confirmed attenuation ratio, correct the signal waveforms associated with the monitoring nodes on both sides. Then, re-check the two sets of corrected signal waveforms to locate the exact location of the fault point. The specific method is as follows: Based on the confirmed line range, randomly select a connection point within this range, and based on the location of the connection point, determine the line length from this connection point to the monitoring nodes on both sides, and record them as C1 and C2 respectively; use: Confirm the attenuation energy E1 associated with the line length C1, where Eo is the preset original energy, e is the base of the natural logarithm, and a is the preset attenuation coefficient. Use B1=(E1÷Eo) to confirm the attenuation ratio B1 associated with the corresponding line; The same processing method is then used to confirm the attenuation ratio B2 associated with the line thread C2; Based on the confirmed attenuation ratios B1 and B2, the monitoring node associated with the corresponding line is determined, and the signal waveform associated with the monitoring node is reversely adjusted to increase the amplitude associated with the signal waveform, thereby obtaining an increased corrected waveform. This corrected waveform, when attenuated by B1 or B2, then obtains the signal waveform associated with the corresponding monitoring node. The two sets of corrected waveforms are shifted left and right in the same two-dimensional plane, and the amplitude difference generated when the two sets of corrected waveforms are at the same time is recorded, and the amplitude difference is ≥ 0. The confirmed sets of amplitude differences are averaged to confirm the characteristic mean associated with the corresponding translation process; the different characteristic means associated with different translation processes are confirmed, and the minimum value is selected from the confirmed different characteristic means. The optimal verification process is determined, and the associated time difference associated with the two sets of corrected waveforms is locked. Based on the same processing method as step 3, it is confirmed whether the currently confirmed fault point is within the line range. If so, the confirmed fault point is marked as the point to be selected. If not, no calibration is performed. According to the determination process of different associated points, the determination process of several different points to be selected can be completed, and the minimum value associated with different points to be selected is calibrated as ZX k , where k represents different points to be selected, and ZX is selected k The to-be-selected point associated with min is recorded as the accurate position point, and is calibrated within the corresponding transmission line based on the confirmed accurate position point.

[0005] Preferably, when the line nodes are confirmed on the left and right, the confirmed distance value is 2m.

[0006] The present invention provides an improved traveling wave ranging method for fault location analysis in distribution networks. Compared with the prior art, it has the following advantages: The present invention uses waveform shift overlap verification to calculate the mean amplitude difference under different shift amounts, automatically identifying the optimal time alignment point and locking the associated time difference t1. This process can effectively correct time errors caused by signal distortion and asynchronous sampling, improving time difference accuracy from microseconds to nanoseconds, laying the foundation for subsequent precise positioning. Multiple associated points are randomly selected within the locked range, a corrected waveform is constructed based on the attenuation ratio and repeatedly verified, and the optimal solution is selected through the characteristic mean minimization algorithm; this mechanism can effectively suppress the error of a single measuring point and improve the robustness of the positioning results through the statistical averaging effect. Even in extreme cases such as high-resistance faults and weak traveling wave signals, the accurate position can still be locked through cross-validation of data from multiple measuring points. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 Schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0008] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0009] See also Figure 1 , the present application provides an improved traveling wave ranging method for distribution network fault location analysis, comprising the following steps: Step 1: Confirm the time of the transient traveling wave signal received by the monitoring nodes on both sides of the distribution network transmission line, and confirm and calibrate the line range interval where the fault point is located based on the confirmed time difference. Specifically, there are line monitoring nodes on the left and right sides of the corresponding transmission line. When there is a fault node in the corresponding transmission line, there will be a corresponding transient traveling wave signal. The corresponding signal will be transmitted to the line monitoring nodes on the left and right sides. Then, the corresponding left and right monitoring nodes will have the specific time of receiving the corresponding signal, so that the time difference can be specifically confirmed. Based on the specific line length of the corresponding transmission line, the range of the fault point is locked, which is convenient for subsequent rapid search of the fault point. The specific method for calibrating the range of the fault point is as follows: Based on the generated transient traveling wave signal, determining the receiving times T1 and T2 associated with the monitoring nodes on both sides of the corresponding transmission line receiving such transient traveling wave signal, where T1 and T2 represent different receiving times associated with different monitoring nodes; Use: Ct = |T1-T2| to determine the time difference Ct between the two groups of receiving times. Based on the set transmission speed v, determine the value difference between the transmission line segments on both sides, and the value difference = Ct × v, where v is a preset value, which is formulated by the operator based on experience and is generally consistent with the speed of light. From the receiving times T1 and T2, select the minimum value and record the monitoring node associated with the minimum value as the low node. Then record the other set of monitoring nodes as the high node. Randomly select a set of line nodes from the transmission line and record the line length L1 from the line node to the low node. Then record the line length L2 from the line node to the high node. By adjusting the line node positions, ensure that (L2 - L1) = the value difference. Based on the determined line node, with this line node as the center point, left and right confirmation is carried out to lock the line range interval where a group of fault points are located. That is, in the left and right confirmation process, the translation distance is generally taken as 2m. Based on this center point, the part of the line associated with 2m before and after is recorded as the confirmed range interval. Specifically, when there is a fault point, the transient traveling wave signal generated by the corresponding point will be transmitted to the two monitoring nodes on the left and right respectively. According to the signal reception time at the corresponding monitoring node, the corresponding time difference can be confirmed, and then the line segment characteristics can be confirmed based on the time difference, so that the corresponding fault node position can be locked, and then the specific confirmation of the interval position can be carried out; Step 2: Based on the signal waveforms associated with the transient traveling wave signals received by the monitoring nodes on both sides, the two sets of signal waveforms are synchronously verified. From the synchronous verification process, the optimal verification process is locked, and the associated time difference is locked from the optimal verification process. Specifically, the so-called associated time difference is the difference in the starting points of the waveforms associated with the corresponding time nodes. That is to say, in the actual process, the signal may fluctuate in advance due to line fluctuations, thereby causing a large problem in the time difference associated with the corresponding monitoring nodes. Through this part of the process, the associated time difference is quickly locked. The specific method for quickly locking the associated time difference is: The signal waveforms associated with the transient traveling wave signals associated with the monitoring nodes on both sides are confirmed, and the two confirmed signal waveforms are checked for overlap. The two signal waveforms are placed in the same two-dimensional plane, with the horizontal coordinate in the two-dimensional plane being the timeline and the vertical coordinate axis being the amplitude. The two signal waveforms are controlled to translate left and right, and in the translation control process, the amplitude difference generated when the two signal waveforms are at the same moment is recorded, and the amplitude difference is ≥0. The confirmed amplitude differences are averaged to confirm the characteristic mean associated with the corresponding translation process. Confirm different feature means associated with different translation processes, select a minimum value from the confirmed different feature means, and record the translation process associated with the minimum value as the optimal verification process; Confirming that the time difference associated between the starting points of the two groups of signal waveforms in the optimal verification process is ≥ 0, and using the determined time difference as the determined associated time difference; Specifically, during the waveform verification process, the corresponding two sets of signal waveforms are shifted left and right, so that in the corresponding processing process, it is possible to identify whether there is a specific situation of time difference. Based on the specific identification processing process, the corresponding time characteristics can be effectively confirmed and comprehensive verification can be performed to achieve the optimal time accuracy determination effect.

[0010] Step 3: Based on the determined associated time difference and line range, recalibrate the time difference associated with the monitoring nodes on both sides. Based on the specific calibration process, confirm the exact location of the fault point. Specifically, if the exact location can be confirmed, directly calibrate it. If the exact location cannot be confirmed, execute the subsequent relevant processing steps, reanalyze, and reconfirm the exact location of the fault point. The specific method of re-calibrating the monitoring nodes on both sides is as follows: Based on the confirmed receiving times T1 and T2 and the associated time difference, the receiving times associated with the monitoring nodes on both sides are readjusted to Z1 and Z2, and the receiving time associated with the signal waveform before the starting point remains unchanged, and the receiving time associated with the signal waveform after the starting point is postponed by t1. Specifically, based on the specific translation process, the corresponding associated time difference is confirmed, and the proposed time difference is t1, where the signal waveform associated with the receiving time T1 is in front, and the signal waveform associated with the receiving time T2 is in the back. Then it is proposed that T1 remains unchanged, that is, T1=Z1, and then T2 is adjusted. The adjusted time is: Z2=(T2-t1). The two sets of receiving times T1 and T2 are confirmed based on the confirmed associated time difference; Based on the adjusted Z1 and Z2, the line nodes are recalibrated in the transmission line using the method for re-determining the line nodes in step 1. The nodes are recorded as sub-nodes, and the sub-nodes are identified to determine whether they are within the line range. If so, the location of the sub-node is recorded as the exact location of the fault point and displayed. If not, the subsequent steps are performed to re-confirm the exact location of the fault point. Specifically, after taking the corresponding time difference into account, the associated line nodes are recalibrated again. According to the specific calibration process, in the state of time difference correction, it is identified whether the confirmed corresponding line node is located within the corresponding line range. Based on the specific identification process, the specific confirmation of the accurate location of the corresponding fault point can be completed quickly, thereby achieving a better process calibration effect. Step 4: Based on the confirmed line range, randomly select a related point within the line range, and confirm the attenuation ratio based on the selected related point and the specific line lengths of the lines on both sides. Then, based on the confirmed attenuation ratio, correct the signal waveforms associated with the monitoring nodes on both sides. Then, re-check the two sets of corrected signal waveforms to lock the exact location of the fault point. The specific method for locking is as follows: Based on the confirmed line range, randomly select a connection point within this range, and based on the location of the connection point, determine the line length from this connection point to the monitoring nodes on both sides, and record them as C1 and C2 respectively; use: Confirm the attenuation energy E1 associated with the line length C1, where Eo is the preset original energy, e is the base of the natural logarithm, generally 2.718281828459045..., and a is the preset attenuation coefficient, which is determined in advance by the operator based on experience. Use B1=(E1÷Eo) to confirm the attenuation ratio B1 associated with the corresponding line; The same processing method is then used to confirm the attenuation ratio B2 associated with the line thread C2; Based on the confirmed attenuation ratios B1 and B2, the monitoring node associated with the corresponding line is determined, and the signal waveform associated with the monitoring node is reversely adjusted to increase the amplitude associated with the signal waveform, thereby obtaining an increased corrected waveform. This corrected waveform, when attenuated by B1 or B2, then obtains the signal waveform associated with the corresponding monitoring node. The two sets of corrected waveforms are shifted left and right in the same two-dimensional plane, and the amplitude difference generated when the two sets of corrected waveforms are at the same time is recorded, and the amplitude difference is ≥ 0. The confirmed sets of amplitude differences are averaged to confirm the characteristic mean associated with the corresponding translation process; the different characteristic means associated with different translation processes are confirmed, and the minimum value is selected from the confirmed different characteristic means. The optimal verification process is determined, and the associated time difference associated with the two sets of corrected waveforms is locked. Based on the same processing method as step 3, it is confirmed whether the currently confirmed fault point is within the line range. If so, the confirmed fault point is marked as the point to be selected. If not, no calibration is performed. According to the determination process of different associated points, the determination process of several different points to be selected can be completed, and the minimum value associated with different points to be selected is calibrated as ZX k , where k represents different points to be selected, and ZX is selected k The point to be selected associated with min is recorded as the accurate position point. According to the confirmed accurate position point, it is marked in the corresponding transmission line to lock the accurate position of the fault point.

[0011] Specifically, according to the step-by-step determination process, the attenuation ratios associated with different lines can be reconfirmed, thereby making specific corrections and adjustments to the signal waveform associated with the designated monitoring node, thereby completing the specific construction of the corresponding correction waveform; Based on the specific processing process, the point features corresponding to different associated points can be quickly locked, and then based on the point features corresponding to several different associated points, the accurate position of the fault point can be quickly locked to achieve a better point locking effect.

[0012] Some of the data in the above formulas are dimensionless and numerically calculated. Meanwhile, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0013] The above embodiments are only used to illustrate the technical method of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical method of the present invention.

Claims

1. An improved traveling wave ranging method for fault location analysis in distribution network, characterized in that: The following steps are involved: Step 1: Confirm the time of transient traveling wave signals received by monitoring nodes on both sides of the distribution network transmission line, and confirm and calibrate the line range where the fault point is located based on the confirmed time difference; Step 2: Based on the signal waveforms associated with the transient traveling wave signals received by the monitoring nodes on both sides, the two sets of signal waveforms are synchronously verified, and the optimal verification process is locked from the synchronous verification process, and the associated time difference is locked from the optimal verification process; Step 3: Based on the determined associated time difference and line range, re-calibrate the time difference associated with the monitoring nodes on both sides, and confirm the exact location of the fault point based on the specific calibration process; Step 4: Randomly select a correlation point within the line range, and confirm the attenuation ratio based on the selected correlation point and the specific line lengths of the lines on both sides. Then, based on the confirmed attenuation ratio, correct the signal waveforms associated with the monitoring nodes on both sides. Then, re-check the two sets of corrected signal waveforms to lock the exact location of the fault point.

2. The improved traveling wave ranging method for fault location analysis in distribution network according to claim 1, characterized in that: In step 1, the specific method of calibrating the range of the fault point is: Based on the generated transient traveling wave signal, determining the receiving times T1 and T2 associated with the monitoring nodes on both sides of the corresponding transmission line receiving such transient traveling wave signal, where T1 and T2 represent different receiving times associated with different monitoring nodes; Use: Ct = |T1-T2| to determine the time difference Ct between the two groups of receiving times. Based on the set transmission speed v, determine the value difference of the transmission line segments on both sides, and the value difference = Ct × v, where v is a preset value; From the receiving times T1 and T2, select the minimum value and record the monitoring node associated with the minimum value as the low node. Then record the other set of monitoring nodes as the high node. Randomly select a set of line nodes from the transmission line and record the line length L1 from the line node to the low node. Then record the line length L2 from the line node to the high node. By adjusting the line node positions, ensure that (L2 - L1) = the value difference. Based on the determined line node, with this line node as the center point, left and right confirmation is performed to lock the line range interval where a group of fault points are located.

3. The improved traveling wave ranging method for fault location analysis in distribution network according to claim 2, characterized in that: When the line nodes are confirmed on the left and right, the confirmed distance value is 2m.

4. The improved traveling wave ranging method for fault location analysis in distribution network according to claim 1, characterized in that: In step 2, the specific method of locking the associated time difference is: The signal waveforms associated with the transient traveling wave signals associated with the monitoring nodes on both sides are confirmed, and the two confirmed signal waveforms are checked for overlap. The two signal waveforms are placed in the same two-dimensional plane, with the horizontal coordinate in the two-dimensional plane being the timeline and the vertical coordinate axis being the amplitude. The two signal waveforms are controlled to translate left and right, and in the translation control process, the amplitude difference generated when the two signal waveforms are at the same moment is recorded, and the amplitude difference is ≥0. The confirmed amplitude differences are averaged to confirm the characteristic mean associated with the corresponding translation process. Confirm different feature means associated with different translation processes, select a minimum value from the confirmed different feature means, and record the translation process associated with the minimum value as the optimal verification process; Confirming the time difference associated between the starting points of the two groups of signal waveforms in the optimal verification process, wherein the time difference is ≥ 0, and using the determined time difference as the determined associated time difference.

5. The improved traveling wave ranging method for fault location analysis in distribution network according to claim 1, characterized in that: In step 3, the specific method of re-checking the monitoring nodes on both sides is: Based on the confirmed receiving times T1 and T2 and the associated time difference, the receiving times associated with the monitoring nodes on both sides are readjusted to Z1 and Z2; Based on the adjusted Z1 and Z2, the line nodes are recalibrated in the transmission line using the method of re-determining the line nodes in step 1, and recorded as sub-nodes. It is then determined whether the sub-nodes are within the line range. If so, the location of the sub-node is recorded as the exact location of the fault point and displayed. If not, the subsequent steps are performed to reconfirm the exact location of the fault point.

6. The improved traveling wave ranging method for distribution network fault location analysis according to claim 5, characterized in that: The specific method of readjusting the receiving time is as follows: The confirmed associated time difference is recorded as t1, and it is confirmed that the receiving time associated with the signal waveform before the starting point remains unchanged, and the receiving time associated with the signal waveform after the starting point is extended by t1.

7. The improved traveling wave ranging method for fault location analysis in distribution network according to claim 1, characterized in that: In step 4, the specific method of correcting the signal waveform is: Based on the confirmed line range, randomly select a connection point within this range, and based on the location of the connection point, determine the line length from this connection point to the monitoring nodes on both sides, and record them as C1 and C2 respectively; use: Confirm the attenuation energy E1 associated with the line length C1, where Eo is the preset original energy, e is the base of the natural logarithm, and a is the preset attenuation coefficient. Use B1=(E1÷Eo) to confirm the attenuation ratio B1 associated with the corresponding line; The same processing method is then used to confirm the attenuation ratio B2 associated with the line thread C2; Based on the confirmed attenuation ratio B1 and attenuation ratio B2, the monitoring node associated with the corresponding line is confirmed, and the signal waveform associated with the monitoring node is adjusted in reverse to increase the amplitude associated with the signal waveform to obtain an increased corrected waveform. This corrected waveform obtains the signal waveform associated with the corresponding monitoring node under the attenuation state of B1 or B2.

8. The improved traveling wave ranging method for fault location analysis in distribution network according to claim 7, characterized in that: In step 4, the specific method for calibrating the accurate position of the fault point is: The two sets of corrected waveforms are shifted left and right in the same two-dimensional plane, and the amplitude difference generated when the two sets of corrected waveforms are at the same moment is recorded, and the amplitude difference is ≥ 0. The determined sets of amplitude differences are averaged to determine the characteristic mean associated with the corresponding translation process; Confirm the different feature means associated with different translation processes, select the minimum value from the confirmed different feature means, and determine the optimal verification process. Then lock the associated time difference associated with the two sets of corrected waveforms. Then, based on the same processing method as step 3, confirm whether the currently confirmed fault point is within the line range. If so, mark the confirmed fault point as the point to be selected. If not, no marking is performed. According to the determination process of different associated points, the determination process of several different points to be selected can be completed, and the minimum value associated with different points to be selected is calibrated as ZX k , where k represents different points to be selected, and ZX is selected k The to-be-selected point associated with min is recorded as the accurate position point, and is calibrated within the corresponding transmission line based on the confirmed accurate position point.

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