A method for measuring the sag of overhead power lines taking into account the robot's own weight

Abstract

This invention discloses a method for measuring the sag of overhead power lines, taking into account the robot's own weight. The method includes the following steps: obtaining the elevations of a first and second power line tower; using a sag measuring robot to collect the real-time elevation of the horizontal midpoint of the conductor / ground wire between the first and second power line towers; and based on the elevations of the first and second power line towers and the real-time elevation of the horizontal midpoint, obtaining the real-time sag of the horizontal midpoint of the conductor / ground wire using a preset sag measurement calculation model. This method is simple and efficient, requires fewer parameters for calculation, and is more convenient to operate. It also accurately eliminates systematic errors caused by the weight of the sag measuring robot, resulting in more precise measurement and calculation results.

Description

Technical Field

[0001] This invention relates to a method for measuring the sag of overhead power lines that takes into account the weight of a robot, and belongs to the technical field of overhead power line sag measurement. Background Technology

[0002] In transmission line construction, sag monitoring is a crucial control item in the stringing process. Effective sag monitoring and adjustment coordinate the relationships between various points on the conductor and ground, water surfaces, and objects being crossed, ensuring safe line operation. Simultaneously, it ensures the line itself is under suitable load conditions, guaranteeing its safe and stable operation.

[0003] There are four commonly used methods for observing traverse sag: the equal-length method, the unequal-length method, the angle method, and the level-view method. Regardless of the method, all involve using optical tools and instruments for manual observation. This method offers advantages in terms of flexibility and convenience, but it is significantly affected by weather, terrain, and other factors, and observation is difficult when the line of sight is obstructed. Furthermore, manual observation is greatly affected by the surveyor's skill level and working condition, leading to significant fluctuations in measurement accuracy and making precise control difficult.

[0004] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for measuring the sag of overhead lines that takes into account the robot's own weight. This method is simple and efficient, requires fewer parameters for calculation, and is more convenient to operate in practice. At the same time, it can accurately eliminate the systematic error caused by the influence of the robot's own weight in sag measurement, making the measurement and calculation results more accurate.

[0006] To achieve the above objectives, the present invention is implemented using the following technical solution:

[0007] This invention discloses a method for measuring the sag of an overhead power line that takes into account the weight of a robot, comprising the following steps:

[0008] Obtain the elevation of the first line tower and the elevation of the second line tower;

[0009] The real-time elevation of the horizontal midpoint of the conductor between the first and second line towers was collected using a sag measurement robot.

[0010] Based on the elevation of the first line tower, the elevation of the second line tower, and the real-time elevation of the horizontal midpoint, the real-time sag of the horizontal midpoint of the conductor is obtained using a preset sag measurement calculation model for the horizontal midpoint.

[0011] The method for constructing the sag measurement calculation model at the horizontal midpoint includes:

[0012] Based on the equal-length method for line sag observation and the catenary equation, a sag observation and calculation model for any point on the conductor and ground line is constructed.

[0013] Based on the principle of the parabolic model of the conductor under a single concentrated load, the maximum sag of the conductor under concentrated loads generated by its own weight and the weight of the sag measurement robot is obtained.

[0014] Based on the maximum sag value and the sag value at the horizontal midpoint of the conductor, the correction value for the influence of the robot's self-weight load at the horizontal midpoint on the sag of the conductor is obtained.

[0015] Based on the sag observation calculation model and correction value at any point on the conductor, the sag measurement calculation model at the horizontal midpoint is obtained.

[0016] Furthermore, the expression for the relaxation observation calculation model at any point on the conductor is:

[0017]

[0018] Where f1 is the calculated sag value at any point on the conductor-ground wire; H is the horizontal tension of the conductor-ground wire; l is the horizontal distance between the first and second line towers; ω is the self-weight per unit length of the conductor-ground wire; h is the height difference between the first and second line towers; ψ is the elevation angle of the height difference between the first and second line towers; h a h is the elevation of the first line tower. b h is the elevation of the second line tower. x Let be the elevation of any point on the guide line.

[0019] Furthermore, the expression for the maximum sag of the ground wire under the concentrated load generated by its own weight and the weight of the sag measuring robot is as follows:

[0020]

[0021] Among them, f cmax ω is the maximum sag of the conductor under the concentrated load generated by its own weight and the weight of the sag measuring robot; Q is the weight of the sag measuring robot; H is the horizontal tension of the conductor; l is the horizontal distance between the first and second line towers; ω is the weight per unit length of the conductor; ψ is the elevation angle of the difference between the first and second line towers.

[0022] Furthermore, the expression for the sag value at the horizontal midpoint of the conductor is:

[0023]

[0024] Among them, f m ω is the sag value at the horizontal midpoint of the conductor-ground wire; H is the horizontal tension of the conductor-ground wire; l is the horizontal distance between the first and second line towers; ω is the self-weight per unit length of the conductor-ground wire; ψ is the elevation angle of the height difference between the first and second line towers.

[0025] Furthermore, the expression for the correction value of the effect of the robot's self-weight load at the horizontal midpoint on the conductor sag is:

[0026]

[0027] Among them, f mΔ denoted as sag value at the horizontal midpoint of the conductor; Q is the self-weight of the sag measuring robot; H is the horizontal tension of the conductor; and l is the horizontal distance between the first and second line towers.

[0028] Furthermore, the expression for the sag measurement calculation model at the horizontal midpoint is:

[0029]

[0030] Where f is the real-time sag at the horizontal midpoint of the conductor; h a h is the elevation of the first line tower. b h is the elevation of the second line tower. c H is the real-time elevation of the horizontal midpoint of the conductor; H is the horizontal tension of the conductor; l is the horizontal distance between the first and second line towers; Q is the self-weight of the sag measuring robot.

[0031] Furthermore, the methods for obtaining the elevation of the first or second line tower include data collection by a sag measurement robot and manual observation.

[0032] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0033] This invention utilizes the principle of equal length method to directly use the collected elevation data for sag calculation, eliminating the error of indirect measurement conversion calculation;

[0034] This invention is based on the calculation principle of the parabolic model, which can meet the accuracy requirements of general line sag measurement. The formula is simpler, the calculation is simpler and more efficient, the calculation requires fewer parameters, and the actual operation is more convenient.

[0035] This invention is based on the principle of concentrated load calculation, which accurately eliminates the systematic error caused by the self-weight of the sag measurement robot, making the measurement and calculation more accurate. Attached Figure Description

[0036] Figure 1This is a schematic diagram illustrating the calculation principle of the concentrated load generated by the self-weight of the overhead line conductor and the self-weight of the sag measurement robot.

[0037] In the diagram: 1. First line tower; 2. Second line tower. Detailed Implementation

[0038] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0039] Example

[0040] This embodiment discloses a method for measuring the sag of an overhead power line that takes into account the robot's own weight, including the following steps:

[0041] Obtain the elevation of the first line tower 1 and the elevation of the second line tower 2;

[0042] The real-time elevation of the horizontal midpoint of the conductor between the first line tower 1 and the second line tower 2 was collected using a sag measurement robot.

[0043] Based on the elevation of the first line tower 1, the elevation of the second line tower 2, and the real-time elevation of the horizontal midpoint, the real-time sag of the horizontal midpoint of the conductor and ground wire is obtained based on the preset sag measurement calculation model of the horizontal midpoint.

[0044] The method for constructing the sag measurement calculation model at the horizontal midpoint includes:

[0045] Based on the equal-length method for line sag observation and the catenary equation, a sag observation and calculation model for any point on the conductor and ground line is constructed.

[0046] Based on the principle of the parabolic model of the conductor under a single concentrated load, the maximum sag of the conductor under concentrated loads generated by its own weight and the weight of the sag measurement robot is obtained.

[0047] Based on the maximum sag value and the sag value at the horizontal midpoint of the conductor, the correction value for the influence of the robot's self-weight load at the horizontal midpoint on the sag of the conductor is obtained.

[0048] Based on the sag observation calculation model and correction value at any point on the conductor-ground line, the sag measurement calculation model at the horizontal midpoint is obtained.

[0049] like Figure 1As shown, in the overhead transmission line in the hilly area, the first line tower 1 and the second line tower 2 are general line towers with conductors suspended at unequal heights; the horizontal distance between the first line tower 1 and the second line tower 2 is the span for line sag observation; the height difference between the first line tower 1 and the second line tower 2 is h; the elevation angle of the height difference between the first line tower 1 and the second line tower 2 is ψ; the distance from the lowest point of the sag of the conductor-ground wire between the first line tower 1 and the second line tower 2 to the first line tower 1 is a; point C is the horizontal midpoint of the conductor-ground wire between the first line tower 1 and the second line tower 2; the elevation of the first line tower 1 is h. a The elevation of the second line tower 2 is h. b The real-time elevation of the horizontal midpoint of the conductor between the first line tower 1 and the second line tower 2 is h. c The elevations of the first line tower 1 and the second line tower 2 are fixed, and the elevation of their horizontal midpoints is h. c The values ​​change in real time as the tensioning process progresses.

[0050] The expression for the relaxation observation calculation model at any point on the conductor is:

[0051]

[0052] According to the catenary equation, substituting it into the formula for the x-coordinate of any point on the overhead line, we can obtain:

[0053]

[0054] Where f1 is the calculated sag value at any point on the conductor-to-ground line; H is the horizontal tension of the conductor-to-ground line; l is the horizontal distance between the first line tower 1 and the second line tower 2; ω is the self-weight per unit length of the conductor-to-ground line; h is the height difference between the first line tower 1 and the second line tower 2; ψ is the elevation angle of the height difference between the first line tower 1 and the second line tower 2; h a h is the elevation of the first line tower 1; b The elevation of tower 2 of the second line; h x Let be the elevation of any point on the guide line.

[0055] Based on the parabolic model principle of the conductor ground wire under a single concentrated load, the expression for the maximum sag of the conductor ground wire under the concentrated load generated by its own weight and the weight of the sag measuring robot is as follows:

[0056]

[0057] Among them, f cmaxω is the maximum sag of the conductor under the concentrated load generated by its own weight and the weight of the sag measuring robot; Q is the weight of the sag measuring robot; H is the horizontal tension of the conductor; l is the horizontal distance between the first line tower 1 and the second line tower 2; ω is the weight per unit length of the conductor; ψ is the elevation angle of the height difference between the first line tower 1 and the second line tower 2.

[0058] Based on the parabolic model principle of the conductor-ground line, the expression for the sag value at the horizontal midpoint of the conductor-ground line is:

[0059]

[0060] Among them, f m ω is the sag value at the horizontal midpoint of the conductor-ground wire; H is the horizontal tension of the conductor-ground wire; l is the horizontal distance between the first line tower 1 and the second line tower 2; ω is the self-weight of the conductor-ground wire per unit length; ψ is the elevation angle of the height difference between the first line tower 1 and the second line tower 2.

[0061] Furthermore, the expression for the correction value of the effect of the robot's self-weight load at the horizontal midpoint on the conductor sag is:

[0062]

[0063] Among them, f mΔ denoted as sag value at the horizontal midpoint of the conductor; Q is the self-weight of the sag measuring robot; H is the horizontal tension of the conductor; l is the horizontal distance between the first line tower 1 and the second line tower 2.

[0064] Finally, the maximum sag of the horizontal midpoint of the overhead line conductor and ground wire, calculated based on the self-weight correction of the sag measurement robot, is obtained. The expression for the sag measurement and calculation model of the horizontal midpoint is as follows:

[0065]

[0066] Where f is the real-time sag at the horizontal midpoint of the conductor; h a h is the elevation of the first line tower 1; b The elevation of tower 2 of the second line; h c H is the real-time elevation of the horizontal midpoint of the conductor; H is the horizontal tension of the conductor; l is the horizontal distance between the first line tower 1 and the second line tower 2; Q is the self-weight of the sag measuring robot.

[0067] The methods for obtaining the elevation of the first line tower 1 or the second line tower 2 include data collection by a sag measurement robot and manual observation.

[0068] It should be noted that the reason for using the horizontal midpoint of the conductor as the measurement point in this invention is as follows: by differentiating the sag expression of any point on the conductor or the sag expression of the conductor under its own weight and the concentrated load generated by the sag measurement robot, we can find that when the lowest point of the sag of the conductor between the first line tower 1 and the second line tower 2 coincides with the horizontal midpoint, that is, when x = a = l / 2, the maximum sag of the conductor under its own weight and the concentrated load generated by the sag measurement robot is reached.

[0069] When the conductor and ground wire are only subjected to their own weight, the sag equation of the overhead line conductor and ground wire using the parabolic model gives the expression for the sag of any point P on the conductor and ground wire as follows:

[0070]

[0071] When the sag measurement robot is operating, the expression for the sag of any point P on the conductor under the self-weight load and the concentrated load generated by the self-weight of the sag measurement robot is:

[0072]

[0073] When the sag measurement robot is operating, its measurement point coincides with the concentrated load point generated by its own weight, which is the robot's location, i.e., point P coincides with point C, at which point a = x. Therefore, the equation can be simplified to:

[0074]

[0075] Differentiating the above formulas yields the maximum sag of the conductor under its own weight and the concentrated load generated by the sag measurement robot's own weight when x = a = l / 2. Since any point on the curve has a corresponding sag, the maximum value is the most representative and can be used to control the degree of conductor sag. Therefore, in actual measurement operations, the horizontal midpoint is the measurement operation point.

[0076] During the sag measurement of the wire tensioning construction, the sag measurement robot moves to point C. As the tensioning construction progresses, the conductor is gradually tightened, and the elevation h of point C is measured. c As the line gradually rises, the sag value f at point C gradually decreases, and the difference between it and the design sag also gradually decreases. When the error value between the design sag and the design sag is less than the error value required by the specification, the conductor sag meets the design requirements, and the tightening work can be completed.

[0077] In actual operation, the sag measurement robot moves into position C, which is the horizontal midpoint. As the tautness construction progresses, the horizontal midpoint will shift to a certain extent, and the robot will move in the opposite direction accordingly, always maintaining a relatively stationary position at point C. That is, the sag measurement robot remains fixed at point C.

[0078] This invention uses a sag measurement robot to obtain the real-time elevation of the horizontal midpoint, calculates the real-time sag, and compares it with the design sag value, thus enabling the measurement and control of track sag. This method has been implemented and tested in the field; the comparison between the measured values ​​and the design values ​​is shown in the table below:

[0079]

[0080]

[0081] Based on the data in the table above, the final sag value of the conductor and ground wire in sections Z116-Z117 is 16.926 meters, compared to the design value of 16.94 meters, a deviation of -0.014 meters, or -0.08%, which is far less than the standard requirement of 2%. This demonstrates that the present invention achieves accurate calculation and precise control of line sag.

[0082] The terms used in this invention are explained as follows:

[0083] Catenary: A flexible line that is fixed and suspended at both ends, forming an arc under the influence of gravity.

[0084] Parabolic model: It is a simplified approximate mathematical model of the catenary, which replaces the complex catenary curve trajectory with the trajectory of the parabola.

[0085] Sag: A catenary is a sag in which the middle part of the catenary droops under the action of gravity.

[0086] Sag: A numerical value representing the degree of sag of an arc, specifically the difference in height at any point on the catenary from the line connecting the two hanging points at that point.

[0087] Concentrated load: A single load applied at any point on a catenary that causes the sag value to be too large or too small. Generally, a concentrated load caused by the self-weight of an object is directed downwards and will result in a larger sag value.

[0088] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0089] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0090] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0091] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0092] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for measuring the sag of an overhead power line taking into account the robot's own weight, characterized in that, Includes the following steps: Obtain the elevation of the first line tower and the elevation of the second line tower; The real-time elevation of the horizontal midpoint of the conductor between the first and second line towers was collected using a sag measurement robot. Based on the elevation of the first line tower, the elevation of the second line tower, and the real-time elevation of the horizontal midpoint, the real-time sag of the horizontal midpoint of the conductor is obtained using a preset sag measurement calculation model for the horizontal midpoint. The method for constructing the sag measurement calculation model at the horizontal midpoint includes: Based on the equal-length method for line sag observation and the catenary equation, a sag observation and calculation model for any point on the conductor and ground line is constructed. Based on the principle of the parabolic model of the conductor under a single concentrated load, the maximum sag of the conductor under concentrated loads generated by its own weight and the weight of the sag measurement robot is obtained. Based on the maximum sag value and the sag value at the horizontal midpoint of the conductor, the correction value for the influence of the robot's self-weight load at the horizontal midpoint on the sag of the conductor is obtained. Based on the sag observation calculation model and correction value at any point on the conductor, the sag measurement calculation model at the horizontal midpoint is obtained; The expression for the relaxation observation calculation model at any point on the conductor is: ； in, f 1 The calculated sag value is the observation value at any point on the conductor-ground line; H For the horizontal tension of the conductor; l The horizontal distance between the first and second line towers; ω The weight per unit length of the conductor / ground wire; h The height difference between the first and second line towers; The elevation angle of the difference between the first and second line towers; h a The elevation of the first line tower; h b The elevation of the second line tower; h x Let be the elevation of any point on the guide line.

2. The method for measuring the sag of overhead lines taking into account the robot's own weight according to claim 1, characterized in that, The expression for the maximum sag of the ground wire under the concentrated load generated by its own weight and the weight of the sag measuring robot is: ； in, f cmax denoted as the maximum sag of the conductor under the concentrated load generated by its own weight and the weight of the sag measuring robot; Q is the weight of the sag measuring robot. H For the horizontal tension of the conductor; l The horizontal distance between the first and second line towers; ω The weight per unit length of the conductor / ground wire; The elevation angle is the difference in elevation between the first and second line towers.

3. The method for measuring the sag of overhead lines taking into account the robot's own weight according to claim 2, characterized in that, The expression for the sag value at the horizontal midpoint of the conductor is: ； in, f m The sag value is the horizontal midpoint of the conductor line; H For the horizontal tension of the conductor; l The horizontal distance between the first and second line towers; ω The weight per unit length of the conductor / ground wire; The elevation angle is the difference in elevation between the first and second line towers.

4. The method for measuring the sag of overhead lines taking into account the robot's own weight according to claim 3, characterized in that, The expression for the correction value of the effect of the robot's self-weight load at the horizontal midpoint on the conductor sag is: ； in, is the sag value at the horizontal midpoint of the guide wire; Q is the self-weight of the sag measurement robot. H For the horizontal tension of the conductor; l The horizontal distance between the first and second line towers.

5. The method for measuring the sag of an overhead line taking into account the robot's own weight according to claim 4, characterized in that, The expression for the sag measurement calculation model at the horizontal midpoint is: ； in, f The real-time sag at the horizontal midpoint of the conductor; h a The elevation of the first line tower; h b The elevation of the second line tower; h c Real-time elevation of the horizontal midpoint of the conductor wire; H For the horizontal tension of the conductor; l denoted as , where is the horizontal distance between the first and second line towers; Q is the weight of the sag measuring robot.

6. The method for measuring the sag of an overhead line taking into account the robot's own weight according to claim 1, characterized in that, The methods for obtaining the elevation of the first or second line tower include data collection by a sag measurement robot and manual observation.

Images