Positioning system and method applied to optical cable fault position

Abstract

The invention discloses a positioning system and method applied to an optical cable fault position, relates to the technical field of optical cable fault positioning, and solves the problems that a positioning result has relatively large deviation in a complex environment and the positioning accuracy is high due to the fact that an existing OTDR (Optical Time Domain Reflectometer) fault positioning method cannot directly and accurately convert a test core length into a specific geographic space position. And the requirement of high-precision geographic space positioning is difficult to meet. The method comprises the following steps: acquiring initial data of an optical fiber link, and establishing a spatial model of the optical fiber link based on the initial data; the method comprises the following steps: segmenting a light link to obtain a plurality of optical cable segments; obtaining a logic distance of a fault point in the optical fiber link based on the OTDR; correcting the length of each optical cable line segment to obtain a target line segment length of each optical cable line segment; and calculating the coordinates of the fault point in the optical fiber link based on the target line segment length of each optical cable line segment and the logic distance of the fault point in the optical fiber link. The technical problem is solved.

Description

Technical Field

[0001] The invention belongs to the field of optical cable fault locating, and in particular relates to a locating system and method for an optical cable fault position. Background Art

[0002] The communication optical cables of wind farms are usually installed in the air or buried underground. The optical cables between wind turbines and booster stations, and between wind turbines are far away. The optical cables are often damaged by geological subsidence, construction damage, farmland cultivation, insect bites, rat bites, natural aging, etc.

[0003] The main method of analyzing optical cable problems in wind farms is for maintenance personnel to use handheld OTDR instruments to analyze the test curves one by one and then record them in a table to guide the maintenance, optimization and fault handling of optical cable lines. However, the manual method is time-consuming, labor-intensive and prone to errors. Existing OTDR fault location methods mainly rely on curve analysis and empirical judgment. Since these methods can only provide the logical distance (test core length) of the fault point in the optical fiber link, and do not combine complex factors such as the actual laying path of the optical fiber, terrain changes, and connector tray retention, it is impossible to directly convert the test core length into a specific geographic spatial location accurately, resulting in large deviations in the positioning results in complex environments, making it difficult to meet the needs of high-precision geographic spatial positioning.

[0004] Therefore, the present invention proposes a system and method for locating a fault position of an optical cable to solve the above-mentioned problem. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art; to this end, the present invention proposes a positioning system and method for optical cable fault location, which is used to solve the technical problem that the existing OTDR fault positioning methods mainly rely on curve analysis and empirical judgment. Since these methods can only provide the logical distance (test core length) of the fault point in the optical fiber link, but do not combine the actual laying path of the optical fiber, terrain changes, and connector tray retention and other complex factors, it is impossible to directly convert the test core length into a specific geographic spatial position, resulting in a large deviation in the positioning result in a complex environment, and it is difficult to meet the needs of high-precision geographic spatial positioning.

[0006] To achieve the above-mentioned object, a first aspect of the present invention provides a positioning system for optical cable fault location, comprising: a data acquisition module, a data analysis module and an optical cable fault positioning module;

[0007] Data acquisition module: obtains the initial data of the optical fiber link and establishes a spatial model of the optical fiber link based on the initial data;

[0008] Data analysis module: by dividing the optical fiber link, several optical cable segments are obtained; the logical distance of the fault point in the optical fiber link is obtained based on the OTDR; and,

[0009] By correcting the length of each optical cable segment, a target segment length of each optical cable segment is obtained;

[0010] Optical cable fault location module: The coordinates of the fault point in the optical fiber link are calculated based on the target segment length of each optical cable segment and the logical distance of the fault point in the optical fiber link.

[0011] Preferably, establishing a spatial model of the optical fiber link based on the initial data comprises:

[0012] Based on the initial data, a spatial model of the optical fiber link is constructed by using a 3D construction software; wherein the initial data includes: optical fiber path, connector position and coil length; the 3D construction software includes: AutoCAD or Blender;

[0013] Taking the starting point of the optical fiber link as the origin, a spatial rectangular coordinate system is established, and the three-dimensional coordinates of each joint position in the optical fiber link are obtained; the three-dimensional coordinates of each joint position are marked as (X i ,Y i ,Z i ), where i is the number of the connector in the optical fiber link, i = {1, 2, 3, ..., N}, and N is the total number of connectors in the optical fiber link.

[0014] It should be noted that the optical fiber path refers to the actual laying route of the optical fiber from the starting point to the end point, including all key nodes (such as the starting point, end point, joints, branch points, etc.) and terrain features (such as mountains, rivers, bridges, etc.) it passes through; the specific description and geographical coordinates of the optical fiber path are obtained through the construction drawings or record files when the optical fiber is laid; the connector position refers to the specific physical location of each connector on the optical fiber link, which is usually used to connect two sections of optical fiber or perform maintenance operations; the connector position is detected through the reflection signal characteristics in the OTDR test data, and the connector usually appears as an obvious peak or mutation point on the OTDR curve; the retained length refers to the extra optical fiber length reserved at certain nodes for the convenience of maintenance or adjustment; the retained length of each node is clearly defined through the design drawings or construction records when the optical fiber is laid.

[0015] Preferably, the method of obtaining a plurality of optical cable segments by dividing the optical fiber link comprises:

[0016] The optical fiber link is divided into several optical cable segments based on the connector positions on the optical fiber link, and the several optical cable segments are marked as Lj; wherein Lj={(X i ,Y i ,Z i ),(X i+1 ,Y i+1 ,Z i+1)}, j refers to the label of each optical cable segment, j = {1,2,3,…,N-1}, and the starting point and end point of each optical cable segment are composed of adjacent connectors.

[0017] It should be noted that, when j=1, the plurality of optical cable segments represents the first optical cable segment, that is, L1={(X1, Y1, Z1), (X2, Y2, Z2)}.

[0018] The present invention constructs a spatial model of an optical fiber link based on initial data, and divides the optical fiber link to obtain several optical cable segments, thereby significantly improving the accuracy and efficiency of optical cable fault location. By using three-dimensional construction software combined with initial data such as optical fiber path, joint position and coil length, the actual laying situation of the optical fiber and its terrain characteristics can be fully reflected, providing an accurate spatial reference for subsequent analysis. A spatial rectangular coordinate system is established with the starting point of the optical fiber link as the origin, and the three-dimensional coordinates of each joint are obtained, thereby further refining the geometric structure description of the optical fiber link, and ensuring that the position information of each optical cable segment is clear and unambiguous. By dividing the optical fiber link based on the joint position, the entire link is divided into several independent optical cable segments, and the starting and ending coordinates are marked, which not only simplifies the processing process of complex links, but also lays a foundation for the subsequent length correction and fault point location of each segment. The positioning deviation problem caused by not fully considering the actual laying path and complex factors in the traditional method is effectively solved, thereby greatly improving the accuracy of the geographic spatial positioning of the optical cable fault point, while reducing the time cost and potential errors of manual analysis, and providing a scientific and reliable basis for the maintenance and optimization of wind farm optical cable lines.

[0019] Preferably, the obtaining of the logical distance of the fault point in the optical fiber link based on the OTDR includes:

[0020] The time t required for the optical signal to propagate from the starting point of the optical fiber link to the fault point and then return to the starting point is obtained through OTDR testing;

[0021] The logical distance of the fault point in the optical fiber link is calculated by the formula d = (c × t) / (2 × IOR); where d is the distance between the starting point of the optical fiber link and the fault point, c is the speed of light in a vacuum, and IOR is the refractive index of the optical fiber.

[0022] It should be noted that the OTDR sends a high-energy laser pulse to the optical fiber. When the optical signal encounters a fault point (such as a breakpoint, joint or other abnormal location), reflected light is generated. The OTDR receives and records the time t when the reflected light returns.

[0023] Preferably, the step of correcting the length of each optical cable segment to obtain the target segment length of each optical cable segment comprises:

[0024] A1: Extract the coordinates of the start and end points of each optical cable segment;

[0025] A2: Obtain the altitudes corresponding to the starting point and the end point of each optical cable segment, and correct the coordinates of the starting point and the end point based on the altitudes to obtain the target starting point coordinates and the target end point coordinates;

[0026] A3: Obtain the longitude and latitude corresponding to the target starting point coordinates and the target end point coordinates, and calculate the length of each optical cable segment based on the longitude and latitude;

[0027] A4: The target segment length of each optical cable segment is calculated based on the coiled length of each optical cable segment and the length of each optical cable segment.

[0028] It should be noted that the coiled length of each optical cable segment can be obtained from the design drawings or construction records when the optical fiber is laid.

[0029] Preferably, the coordinates of the starting point and the end point are corrected based on the altitude, including:

[0030] The altitude of each connector in the optical fiber link is obtained through DEM and marked as H. i ;

[0031] The three-dimensional coordinates of each joint position are corrected based on the altitude of each joint in the optical fiber link, specifically: Lj'={(X i ,Y i ,Z i +H i ),(X i+1 ,Y i+1 ,Z i+1 +H i+1 )}; where (X i ,Y i ,Z i +H i ) is the target starting point coordinate obtained after the coordinates of the starting point of the optical cable segment are corrected, (X i+1 ,Y i+1 ,Z i+1 +H i+1 ) is the target end point coordinates obtained after the coordinates of the end point of the optical cable segment are corrected, and Lj' is the new optical cable segment obtained after the coordinates of the start and end points of the optical cable segment are corrected.

[0032] Preferably, the calculating the length of each optical cable segment based on the longitude and latitude includes:

[0033] Obtain the longitude and latitude corresponding to the target starting point coordinates and target end point coordinates of each optical cable segment, and mark them as (φi, λi) and (φi+1, λi+1) respectively; where φi represents the longitude of the i-th connector, and λi represents the latitude of the i-th connector;

[0034] By formula:

[0035]

[0036] The length of each optical cable segment is calculated; where dLj refers to the length of the j-th optical cable segment, and R is the radius of the earth.

[0037] It should be noted that the starting point and end point of each optical cable segment are: the starting point is the connection point (connector) between the optical cable segment and the previous optical cable segment or the starting point of the optical fiber link, and the end point is the connection point (connector) between the optical cable segment and the next optical cable segment or the end point of the optical fiber link.

[0038] Preferably, the step of calculating the target segment length of each optical cable segment based on the coiled length of each optical cable segment and the length of each optical cable segment comprises:

[0039] Extract the coiled length of each optical cable segment;

[0040] The target segment length of each optical cable segment is obtained by calculating the sum of the coiled length of each optical cable segment and the length of each optical cable segment.

[0041] The present invention corrects the length of each optical cable segment to finally obtain the target segment length, thereby significantly improving the accuracy and reliability of optical fiber link fault positioning; by extracting the coordinates of the starting point and the end point of each optical cable segment and correcting the coordinates in combination with the altitude data obtained by DEM, the influence of terrain undulation on length calculation is effectively compensated, ensuring that the true geometric shape of the optical cable segment in three-dimensional space is accurately reflected; based on the longitude and latitude corresponding to the corrected target starting point and end point coordinates, the actual length of each optical cable segment is calculated using the earth radius and a formula, further considering the geographical curvature factor, and avoiding the error that may be caused by plane calculation; the coiled length of each optical cable segment is added to the calculated length to obtain the target segment length, fully considering the influence of the additional length reserved during optical fiber laying on the total length.

[0042] Preferably, the step of calculating the coordinates of the fault point in the optical fiber link based on the target segment length of each optical cable segment and the logical distance of the fault point in the optical fiber link comprises:

[0043] B1: The optical cable segment where the fault point is located is marked as k; the target segment length of each optical cable segment is marked as mdLj; where mdLj refers to the target segment length of the jth optical cable segment;

[0044] B2: Determine whether the judgment condition is met when j=1: If yes, then output k=j, indicating that the fault point is located on the kth optical cable segment; if no, set j=j+1, and continue to judge until the judgment condition is met, and output the corresponding value of k;

[0045] B3: By formula The proportional position of the fault point on the kth optical cable segment is calculated; wherein Q is the proportional position of the fault point on the kth optical cable segment, and mdLk is the target segment length of the kth optical cable segment;

[0046] B4: The coordinates of the fault point in the optical fiber link are calculated based on the proportional position of the fault point on the kth optical cable segment;

[0047] The coordinates of the fault point in the optical fiber link are specifically:

[0048] (X d ,Y d ,Z d )=(X k ,Y k ,Z k )+Q×[(X k+1 -X k ),(Y k+1 -Y k ),(Z k+1 -Z k )]; where (X d ,Y d ,Z d ) is the coordinate of the fault point in the optical fiber link, (X k ,Y k ,Z k ) are the starting coordinates of the kth optical cable segment.

[0049] A second aspect of the present invention provides a method for locating a fault position of an optical cable, comprising:

[0050] Step 1: Obtain initial data of the optical fiber link, and establish a spatial model of the optical fiber link based on the initial data;

[0051] Step 2: Divide the optical fiber link into several optical cable segments; obtain the logical distance of the fault point in the optical fiber link based on the OTDR;

[0052] Step 3: Correcting the length of each optical cable segment to obtain a target segment length of each optical cable segment;

[0053] Step 4: The coordinates of the fault point in the optical fiber link are calculated based on the target segment length of each optical cable segment and the logical distance of the fault point in the optical fiber link.

[0054] Compared with the prior art, the present invention has the following beneficial effects:

[0055] 1. Existing OTDR fault location methods mainly rely on curve analysis and empirical judgment. Since these methods can only provide the logical distance (test core length) of the fault point in the optical fiber link, without combining the actual laying path of the optical fiber, terrain changes, joint tray retention and other complex factors, it is impossible to directly convert the test core length into a specific geographic space position accurately, resulting in a large deviation in the positioning result in a complex environment, and it is difficult to meet the technical problem of the demand for high-precision geographic space positioning; the present invention obtains the initial data of the optical fiber link and establishes a spatial model of the optical fiber link based on the initial data; divides the optical fiber link to obtain a plurality of optical cable segments; obtains the logical distance of the fault point in the optical fiber link based on OTDR; corrects the length of each optical cable segment to obtain the target segment length of each optical cable segment; calculates the coordinates of the fault point in the optical fiber link based on the target segment length of each optical cable segment and the logical distance of the fault point in the optical fiber link, thereby solving the technical problem that the positioning result of the prior art has a large deviation in a complex environment and is difficult to meet the demand for high-precision geographic space positioning.

[0056] 2. The present invention extracts the coordinates of the starting point and the end point of each optical cable segment, and corrects the coordinates in combination with the altitude data obtained by DEM, thereby effectively compensating for the influence of terrain undulations on length calculation and ensuring that the true geometric shape of the optical cable segment in three-dimensional space is accurately reflected; based on the longitude and latitude corresponding to the corrected target starting point and end point coordinates, the actual length of each optical cable segment is calculated using the earth radius and formula, further considering the geographical curvature factor and avoiding the error that may be caused by plane calculation; the coiled length of each optical cable segment is added to the calculated length to obtain the target segment length, fully considering the influence of the additional length reserved during optical fiber laying on the total length, thereby achieving a comprehensive restoration of the actual physical length of the optical cable, not only greatly improving the accuracy of optical cable length measurement, but also providing reliable basic data support for the subsequent fault point positioning based on the conversion of logical distance into geographic space position, effectively solving the positioning deviation problem caused by ignoring factors such as terrain changes and coiled length in the existing method, and significantly improving the efficiency and accuracy of wind farm optical cable maintenance and fault handling. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0058] Figure 1 A schematic diagram of a system module according to an embodiment of the present invention;

[0059] Figure 2 A schematic diagram of a method for correcting the length of an optical cable segment according to an embodiment of the present invention;

[0060] Figure 3 Schematic diagram of the method steps of an embodiment of the present invention. DETAILED DESCRIPTION

[0061] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] See also Figure 1 , the first aspect of the present invention provides a positioning system for optical cable fault location, including: a data acquisition module, a data analysis module and an optical cable fault positioning module;

[0063] Data acquisition module: obtains the initial data of the optical fiber link and establishes a spatial model of the optical fiber link based on the initial data;

[0064] Data analysis module: by dividing the optical fiber link, several optical cable segments are obtained; the logical distance of the fault point in the optical fiber link is obtained based on the OTDR; and,

[0065] By correcting the length of each optical cable segment, a target segment length of each optical cable segment is obtained;

[0066] Optical cable fault location module: The coordinates of the fault point in the optical fiber link are calculated based on the target segment length of each optical cable segment and the logical distance of the fault point in the optical fiber link.

[0067] A spatial model of the optical fiber link is established based on the initial data, including:

[0068] Based on the initial data, a spatial model of the optical fiber link is constructed by using a 3D construction software; wherein the initial data includes: optical fiber path, connector position and coil length; the 3D construction software includes: AutoCAD or Blender;

[0069] Taking the starting point of the optical fiber link as the origin, a spatial rectangular coordinate system is established, and the three-dimensional coordinates of each joint position in the optical fiber link are obtained; the three-dimensional coordinates of each joint position are marked as (X i ,Y i ,Z i ), where i is the number of the connector in the optical fiber link, i = {1, 2, 3, ..., N}, and N is the total number of connectors in the optical fiber link.

[0070] By cutting the optical fiber link, several optical cable segments are obtained, including:

[0071] The optical fiber link is divided into several optical cable segments based on the connector positions on the optical fiber link, and the several optical cable segments are marked as Lj; wherein Lj={(X i ,Y i ,Z i ),(X i+1 ,Y i+1 ,Z i+1 )}, j refers to the label of each optical cable segment, j = {1,2,3,…,N-1}, and the starting point and end point of each optical cable segment are composed of adjacent connectors.

[0072] Obtain the logical distance of the fault point in the optical fiber link based on OTDR, including:

[0073] The time t required for the optical signal to propagate from the starting point of the optical fiber link to the fault point and then return to the starting point is obtained through OTDR testing;

[0074] The logical distance of the fault point in the optical fiber link is calculated by the formula d = (c × t) / (2 × IOR); where d is the distance between the starting point of the optical fiber link and the fault point, c is the speed of light in a vacuum, and IOR is the refractive index of the optical fiber.

[0075] See also Figure 2 , by correcting the length of each optical cable segment, the target segment length of each optical cable segment is obtained, including:

[0076] A1: Extract the coordinates of the start and end points of each optical cable segment;

[0077] A2: Obtain the altitudes corresponding to the starting point and the end point of each optical cable segment, and correct the coordinates of the starting point and the end point based on the altitudes to obtain the target starting point coordinates and the target end point coordinates;

[0078] A3: Obtain the longitude and latitude corresponding to the target starting point coordinates and the target end point coordinates, and calculate the length of each optical cable segment based on the longitude and latitude;

[0079] A4: The target segment length of each optical cable segment is calculated based on the coiled length of each optical cable segment and the length of each optical cable segment.

[0080] Correct the coordinates of the start and end points based on the altitude, including:

[0081] The altitude of each connector in the optical fiber link is obtained through DEM and marked as H. i ;

[0082] The three-dimensional coordinates of each joint position are corrected based on the altitude of each joint in the optical fiber link, specifically: Lj'={(X i ,Y i ,Z i +H i ),(X i+1 ,Y i+1 ,Z i+1 +H i+1 )}; where (X i ,Y i ,Z i +H i ) is the target starting point coordinate obtained after the coordinates of the starting point of the optical cable segment are corrected, (X i+1 ,Y i+1 ,Z i+1 +H i+1 ) is the target end point coordinates obtained after the coordinates of the end point of the optical cable segment are corrected, and Lj' is the new optical cable segment obtained after the coordinates of the start and end points of the optical cable segment are corrected.

[0083] The length of each optical cable segment is calculated based on longitude and latitude, including:

[0084] Obtain the longitude and latitude corresponding to the target starting point coordinates and target end point coordinates of each optical cable segment, and mark them as (φi, λi) and (φi+1, λi+1) respectively; where φi represents the longitude of the i-th connector, and λi represents the latitude of the i-th connector;

[0085] By formula:

[0086]

[0087] The length of each optical cable segment is calculated; where dLj refers to the length of the j-th optical cable segment, and R is the radius of the earth.

[0088] The target segment length of each optical cable segment is calculated based on the coiled length of each optical cable segment and the length of each optical cable segment, including:

[0089] Extract the coiled length of each optical cable segment;

[0090] The target segment length of each optical cable segment is obtained by calculating the sum of the coiled length of each optical cable segment and the length of each optical cable segment.

[0091] The coordinates of the fault point in the optical fiber link are calculated based on the target segment length of each optical cable segment and the logical distance of the fault point in the optical fiber link, including:

[0092] B1: The optical cable segment where the fault point is located is marked as k; the target segment length of each optical cable segment is marked as mdLj; where mdLj refers to the target segment length of the jth optical cable segment;

[0093] B2: Determine whether the judgment condition is met when j=1: If yes, then output k=j, indicating that the fault point is located on the kth optical cable segment; if no, set j=j+1, and continue to judge until the judgment condition is met, and output the corresponding value of k;

[0094] B3: By formula The proportional position of the fault point on the kth optical cable segment is calculated; wherein Q is the proportional position of the fault point on the kth optical cable segment, and mdLk is the target segment length of the kth optical cable segment;

[0095] B4: The coordinates of the fault point in the optical fiber link are calculated based on the proportional position of the fault point on the kth optical cable segment;

[0096] The coordinates of the fault point in the optical fiber link are specifically:

[0097] (X d ,Y d ,Z d )=(X k ,Y k ,Z k )+Q×[(X k+1 -X k ),(Y k+1 -Y k ),(Z k+1 -Z k )]; where (X d ,Y d ,Z d ) is the coordinate of the fault point in the optical fiber link, (X k ,Y k ,Z k ) are the starting coordinates of the kth optical cable segment.

[0098] For example, suppose a wind farm optical cable link is laid in a complex terrain, with the starting point being wind turbine A and the end point being booster station B. The entire optical cable link is connected by four connectors (including the starting point and the end point). The following is a detailed example analysis based on the method of the present invention:

[0099] 1. Data collection and spatial model construction;

[0100] Fiber optic path: According to the construction drawings, the fiber optic cable starts from wind turbine A, passes through mountains, rivers and bridges, and finally reaches booster station B.

[0101] Connector Location:

[0102] Joint 1 (starting point): coordinates are (X1, Y1, Z1);

[0103] Joint 2: coordinates are (X2, Y2, Z2);

[0104] Joint 3: coordinates are (X3, Y3, Z3);

[0105] Joint 4 (end point): coordinates are (X4, Y4, Z4);

[0106] Coil length:

[0107] The coil length between joint 1 and joint 2 is 100m;

[0108] The coil length between joint 2 and joint 3 is 150m;

[0109] The length of the coil between joint 3 and joint 4 is 120m;

[0110] Use AutoCAD software to establish a spatial rectangular coordinate system with fan A as the origin, and mark the position of each joint as a three-dimensional coordinate.

[0111] 2. Fiber link segmentation;

[0112] According to the connector position, the optical fiber link is divided into three cable segments:

[0113] The first optical cable segment L1 = {(X1, Y1, Z1), (X2, Y2, Z2)};

[0114] The second optical cable segment L2 = {(X2, Y2, Z2), (X3, Y3, Z3)};

[0115] The third optical cable segment L3 = {(X3, Y3, Z3), (X4, Y4, Z4)};

[0116] 3. OTDR test to obtain logical distance;

[0117] Use OTDR equipment to send high-energy laser pulses to the optical fiber and record the time t = 20 μs for the reflected light to return. It is known that the speed of light in a vacuum is c = 3 × 10 8 m / s, fiber refractive index IOR = 1.46, then the logical distance is calculated as follows:

[0118] d = (c × t) / (2 × IOR) = (3 × 10 8 ×20×10 -6 ) / (2×1.46)=2054.79m;

[0119] Therefore, the logical distance of the fault point is 2054.79m.

[0120] 4. Correction of length of each optical cable segment;

[0121] The altitude of each joint is obtained through DEM: joint 1 is H1, joint 2 is H2, joint 3 is H3, and joint 4 is H4;

[0122] Assume that the corrected line segment and coordinates are:

[0123] L1'={(X1,Y1,Z1+H1),(X2,Y2,Z2+H2)};

[0124] L2'={(X2,Y2,Z2+H2),(X3,Y3,Z3+H3)};

[0125] L3'={(X3,Y3,Z3+H3),(X4,Y4,Z4+H4)};

[0126] Latitude and longitude calculation;

[0127] Assume that the longitude and latitude of each joint are:

[0128] Joint 1: (φ1,λ1);

[0129] Joint 2: (φ2,λ2);

[0130] Joint 3: (φ3,λ3);

[0131] Joint 4: (φ4,λ4);

[0132] Convert longitude and latitude to radians and substitute into the formula:

[0133]

[0134] The length of each segment of optical cable is calculated; where the radius of the earth is R = 6371 km;

[0135] Assume that the calculation is:

[0136] dL1=1113m;

[0137] dL2=1210m;

[0138] dL3=1410m;

[0139] Coil retention length correction;

[0140] Combined with the length of the disk, the target line segment length is obtained:

[0141] mdL1=dL1+100=1213m;

[0142] mdL2=dL2+150=1360m;

[0143] mdL3=dL3+120=1530m;

[0144] 5. Fault point location;

[0145] Determine the optical cable segment where the fault point is located;

[0146] Since mdL1+mdL2<d<mdL1+mdL2+mdL3;

[0147] Therefore, the fault point is on the second optical cable segment, that is, k = 2;

[0148] (2) Calculate the proportional position;

[0149] The proportional position of the fault point on the second optical cable segment is:

[0150] Q=(2054.79-1213) / 1360≈0.62;

[0151] Calculate the coordinates of the fault point;

[0152] The coordinates of the fault point in the optical fiber link are calculated based on the proportional position of the fault point on the kth optical cable segment;

[0153] The coordinates of the fault point in the optical fiber link are specifically: d ,Y d ,Z d )=(X2,Y2,Z2)+Q×[(X3-X2),(Y3-Y2),(Z3-Z2)]; among them, (X d ,Y d ,Z d ) are the coordinates of the fault point in the optical fiber link.

[0154] This embodiment significantly improves the accuracy and reliability of optical cable fault location by combining complex factors such as the actual laying path of the optical fiber link, terrain characteristics, and the length of the joint coil. First, the spatial model of the optical fiber link is constructed based on the initial data using AutoCAD software, and the altitude of each joint is obtained through DEM to correct the coordinates, which fully reflects the actual laying of the optical fiber and its three-dimensional spatial characteristics. Secondly, by dividing the optical fiber link and calculating the actual length of each optical cable segment, the geographical distance is accurately calculated in combination with the longitude and latitude and the radius of the earth, and the influence of the coil length is considered to correct the target segment length, thereby ensuring the accuracy of the length of each optical cable segment. Finally, based on the logical distance obtained by the OTDR test and the corrected target segment length, the geographic spatial coordinates of the fault point are accurately located by proportional calculation, which effectively solves the positioning deviation problem caused by ignoring factors such as terrain changes and coil length in the existing method. At the same time, it not only greatly improves the accuracy of optical cable fault point location, but also simplifies the processing process of complex links, reduces the time cost and potential errors of manual analysis, and provides a scientific and reliable solution for the maintenance, optimization and fault handling of wind farm optical cable lines, especially in complex terrain environments. It shows excellent adaptability and practicality.

[0155] See also Figure 3 The second aspect of the present invention provides a method for locating a fault position of an optical cable, comprising:

[0156] Step 1: Obtain initial data of the optical fiber link, and establish a spatial model of the optical fiber link based on the initial data;

[0157] Step 2: Divide the optical fiber link into several optical cable segments; obtain the logical distance of the fault point in the optical fiber link based on the OTDR;

[0158] Step 3: Correcting the length of each optical cable segment to obtain a target segment length of each optical cable segment;

[0159] Step 4: The coordinates of the fault point in the optical fiber link are calculated based on the target segment length of each optical cable segment and the logical distance of the fault point in the optical fiber link.

[0160] Part of the data in the above formula is calculated by removing the dimension and taking its numerical value. The formula is a formula closest to the actual situation obtained by software simulation of a large amount of collected data; the preset parameters and preset thresholds in the formula are set by technical personnel in this field according to actual conditions or obtained through simulation of a large amount of data.

[0161] Working principle of the present invention:

[0162] The present invention obtains initial data of an optical fiber link and establishes a spatial model of the optical fiber link based on the initial data; obtains a plurality of optical cable segments by dividing the optical fiber link; obtains the logical distance of a fault point in the optical fiber link based on an OTDR; obtains the target segment length of each optical cable segment by correcting the length of each optical cable segment; and calculates the coordinates of the fault point in the optical fiber link based on the target segment length of each optical cable segment and the logical distance of the fault point in the optical fiber link, thereby solving the technical problem that the existing OTDR fault location method mainly relies on curve analysis and empirical judgment, and these methods can only provide the logical distance (test core length) of the fault point in the optical fiber link without combining the actual laying path of the optical fiber, terrain changes, joint tray retention and other complex factors, so it is impossible to directly and accurately convert the test core length into a specific geographic space position, resulting in a large deviation in the positioning result in a complex environment, and it is difficult to meet the demand for high-precision geographic space positioning.

[0163] The above embodiments are only used to illustrate the technical method of the present invention rather than to limit it. 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. A positioning system for optical cable fault location, characterized in that: include: Data acquisition module, data analysis module and optical cable fault location module; Data acquisition module: obtains the initial data of the optical fiber link and establishes a spatial model of the optical fiber link based on the initial data; Data analysis module: by dividing the optical fiber link, several optical cable segments are obtained; Obtaining the logical distance of the fault point in the optical fiber link based on OTDR; and, By correcting the length of each optical cable segment, a target segment length of each optical cable segment is obtained; Optical cable fault location module: The coordinates of the fault point in the optical fiber link are calculated based on the target segment length of each optical cable segment and the logical distance of the fault point in the optical fiber link.

2. A positioning system for optical cable fault location according to claim 1, characterized in that: The establishing of the spatial model of the optical fiber link based on the initial data comprises: Based on the initial data, a spatial model of the optical fiber link is constructed by using a 3D construction software; wherein the initial data includes: optical fiber path, connector position and coil length; the 3D construction software includes: AutoCAD or Blender; Taking the starting point of the optical fiber link as the origin, a spatial rectangular coordinate system is established, and the three-dimensional coordinates of each joint position in the optical fiber link are obtained; the three-dimensional coordinates of each joint position are marked as (X i ,Y i ,Z i ), where i is the number of the connector in the optical fiber link, i = {1, 2, 3, ..., N}, and N is the total number of connectors in the optical fiber link.

3. A positioning system for optical cable fault location according to claim 1, characterized in that: The optical fiber link is divided to obtain a plurality of optical cable segments, including: The optical fiber link is divided into several optical cable segments based on the connector positions on the optical fiber link, and the several optical cable segments are marked as Lj; wherein Lj={(X i ,Y i ,Z i ),(X i+1 ,Y i+1 ,Z i+1 )}, j refers to the label of each optical cable segment, j = {1,2,3,…,N-1}, and the starting point and end point of each optical cable segment are composed of adjacent connectors.

4. A positioning system for optical cable fault location according to claim 1, characterized in that: The method of obtaining the logical distance of the fault point in the optical fiber link based on the OTDR includes: The time t required for the optical signal to propagate from the starting point of the optical fiber link to the fault point and then return to the starting point is obtained through OTDR testing; The logical distance of the fault point in the optical fiber link is calculated by the formula d = (c × t) / (2 × IOR); where d is the distance between the starting point of the optical fiber link and the fault point, c is the speed of light in a vacuum, and IOR is the refractive index of the optical fiber.

5. A positioning system for optical cable fault location according to claim 1, characterized in that: The method of correcting the length of each optical cable segment to obtain the target segment length of each optical cable segment includes: A1: Extract the coordinates of the start and end points of each optical cable segment; A2: Obtain the altitudes corresponding to the starting point and the end point of each optical cable segment, and correct the coordinates of the starting point and the end point based on the altitudes to obtain the target starting point coordinates and the target end point coordinates; A3: Obtain the longitude and latitude corresponding to the target starting point coordinates and the target end point coordinates, and calculate the length of each optical cable segment based on the longitude and latitude; A4: The target segment length of each optical cable segment is calculated based on the coiled length of each optical cable segment and the length of each optical cable segment.

6. A positioning system for optical cable fault location according to claim 5, characterized in that: The step of correcting the coordinates of the starting point and the end point based on the altitude includes: The altitude of each connector in the optical fiber link is obtained through DEM and marked as H. i ; The three-dimensional coordinates of each joint position are corrected based on the altitude of each joint in the optical fiber link, specifically: Lj'={(X i ,Y i ,Z i +H i ),(X i+1 ,Y i+1 ,Z i+1 +H i+1 )}; where (X i ,Y i ,Z i +H i ) is the target starting point coordinate obtained after the coordinates of the starting point of the optical cable segment are corrected, (X i+1 ,Y i+1 ,Z i+1 +H i+1 ) is the target end point coordinates obtained after the coordinates of the end point of the optical cable segment are corrected, and Lj' is the new optical cable segment obtained after the coordinates of the start and end points of the optical cable segment are corrected.

7. A positioning system for optical cable fault location according to claim 5, characterized in that: The method of calculating the length of each optical cable segment based on the longitude and latitude includes: Obtain the longitude and latitude corresponding to the target starting point coordinates and target end point coordinates of each optical cable segment, and mark them as (φi, λi) and (φi+1, λi+1) respectively; where φi represents the longitude of the i-th connector, and λi represents the latitude of the i-th connector; By formula: The length of each optical cable segment is calculated; where dLj refers to the length of the j-th optical cable segment, and R is the radius of the earth.

8. A positioning system for optical cable fault location according to claim 5, characterized in that: The step of calculating the target segment length of each optical cable segment based on the coiled length of each optical cable segment and the length of each optical cable segment comprises: Extract the coiled length of each optical cable segment; The target segment length of each optical cable segment is obtained by calculating the sum of the coiled length of each optical cable segment and the length of each optical cable segment.

9. A positioning system for optical cable fault location according to claim 1, characterized in that: The step of calculating the coordinates of the fault point in the optical fiber link based on the target segment length of each optical cable segment and the logical distance of the fault point in the optical fiber link comprises: B1: The optical cable segment where the fault point is located is marked as k; the target segment length of each optical cable segment is marked as mdLj; where mdLj refers to the target segment length of the jth optical cable segment; B2: Determine whether the judgment condition is met when j=1: If yes, then output k=j, indicating that the fault point is located on the kth optical cable segment; if no, set j=j+1, and continue to judge until the judgment condition is met, and output the corresponding value of k; B3: By formula The proportional position of the fault point on the kth optical cable segment is calculated; wherein Q is the proportional position of the fault point on the kth optical cable segment, and mdLk is the target segment length of the kth optical cable segment; B4: The coordinates of the fault point in the optical fiber link are calculated based on the proportional position of the fault point on the kth optical cable segment; The coordinates of the fault point in the optical fiber link are specifically: (X d ,Y d ,Z d )=(X k ,Y k ,Z k )+Q×[(X k+1 -X k ),(Y k+1 -Y k ),(Z k+1 -Z k )]; where (X d ,Y d ,Z d ) is the coordinate of the fault point in the optical fiber link, (X k ,Y k ,Z k ) are the starting coordinates of the kth optical cable segment.

10. A method for locating a fault position of an optical cable, applied to a positioning system for locating a fault position of an optical cable as claimed in any one of claims 1 to 9, characterized in that: include: Step 1: Obtain initial data of the optical fiber link, and establish a spatial model of the optical fiber link based on the initial data; Step 2: Divide the optical fiber link to obtain several optical cable segments; Obtain the logical distance of the fault point in the optical fiber link based on OTDR; Step 3: Correcting the length of each optical cable segment to obtain a target segment length of each optical cable segment; Step 4: The coordinates of the fault point in the optical fiber link are calculated based on the target segment length of each optical cable segment and the logical distance of the fault point in the optical fiber link.

Images