Overhead Line Sag Measurement Method Based on the Fusion of Beidou Positioning and Laser Ranging

Abstract

The present invention relates to a method for measuring the sag of overhead lines based on the fusion of Beidou positioning and laser ranging. This method measures the sag based on a sag intelligent measurement and control device, and the method includes: placing the sag intelligent measurement and control device directly below the overhead line, and adjusting the pose of the adjustable support device according to the detection data of the universal inclination sensor; driving the laser ranging module to change the angle through the rotary platform mechanism for fuzzy measurement, and recording the position when the laser feedback signal is obtained; at each recorded position, performing fine measurement, and obtaining the position of the coordinate point at this time when the laser feedback signal is obtained, and obtaining the actual measured value of the sag; thereby constructing the actual curve of the overhead line and comparing it with the standard curve of the overhead line to realize the monitoring of the sag of the overhead line. Compared with the prior art, the present invention can improve the quality of sag detection, improve the operation efficiency of tensioning wire construction in the project, and reduce the labor cost of construction personnel.

Description

Technical Field

[0001] The present invention relates to the technical field of overhead line measurement, and particularly to a method for measuring the sag of overhead lines based on the fusion of Beidou positioning and laser ranging. Background Technique

[0002] The conductors of transmission lines droop between adjacent towers to form an arc curve, and the degree of droop is called the sag. The size of the sag is related to the span, height difference, conductor length, conductor weight, and stress on the conductor. Natural factors such as temperature, wind, ice, and snow also affect it. In order to ensure the safe operation of the overhead lines of extra-high voltage and ultra-high voltage transmission under harsh meteorological conditions and to ensure that the distances between the transmission conductors and the ground and the objects being crossed meet the requirements of the "Code for Construction and Acceptance of 110-750 kV Overhead Transmission Lines", it is necessary to accurately control the sag of the overhead transmission lines during stringing construction. Especially in mountainous areas, water networks and other areas, one of the core issues restricting the project progress and quality is that the manual sag observation is affected by the environment and has limited efficiency. Currently, the sag observation method mainly relies on manual observation and judgment, which requires high experience and professional qualities of the observers. Moreover, when observing on the tower, there are problems such as high manual labor intensity and personal safety.

[0003] The main disadvantages of manual sag observation are: (1) The detection efficiency is low, and it has high requirements for the environment. In the case of poor visibility, manual sag observation cannot be carried out; (2) It has relatively high requirements for the experience of the observers and they must have certain professional experience; (3) The sag data obtained by manual observation lacks objectivity and consistency. Therefore, it is of great significance to study an efficient and high-precision method for sag measurement and control. Summary of the Invention

[0004] The purpose of the present invention is to overcome the defects of the above-mentioned existing technologies and provide a method for measuring the sag of overhead lines based on the fusion of Beidou positioning and laser ranging, so as to realize the intelligent and digital high-precision detection of the sag of the target conductor, improve the quality of sag detection, enhance the operation efficiency of the stringing construction in the project, and reduce the labor cost of construction personnel.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A method for measuring the sag of overhead lines based on the fusion of Beidou positioning and laser ranging. This method measures the sag based on an intelligent sag measurement and control device. The intelligent sag measurement and control device includes an adjustable support device, a support platform, and a Beidou positioning device, a laser ranging module, and a rotary platform mechanism installed on the support platform. The support platform is installed on the adjustable support device, the Beidou positioning device is connected to the support platform, and the support platform is also provided with a universal inclination sensor for monitoring the pose data of the device.

[0007] The method includes the following steps:

[0008] Positioning step: Place the sag intelligent measurement and control device directly below the overhead line, deploy the adjustable support device, and adjust the pose of the adjustable support device according to the detection data of the universal inclination sensor so that the support platform is in a horizontal state;

[0009] Fuzzy measurement step: Drive the laser ranging module by the rotating platform mechanism to change the angle within a preset initial angle range for measurement. When a laser feedback signal is obtained, record the position and determine the laser dotting angle range of the current feedback position;

[0010] Fine measurement step: At each feedback position, drive the laser ranging module by the rotating platform mechanism to change the angle within the corresponding laser dotting angle range for measurement. After obtaining the laser feedback signal, perform repeated measurement confirmation to obtain the position of the coordinate point at this time; According to the angle information of the device and the distance information of the laser point at this time, and combined with the real-time position coordinates of the Beidou positioning module, obtain the actual measurement value of the sag;

[0011] Monitoring step: Construct the actual curve of the overhead line according to the actual measurement value of the sag, compare it with the standard curve of the overhead line, and calculate the tight line amount data of the current overhead line.

[0012] Further, the monitoring step is specifically as follows: Establish a sag coordinate system according to the obtained actual measurement values of multiple sags, perform curve fitting under this sag coordinate system to obtain the actual curve of the overhead line; Compare the actual curve of this overhead line with the standard curve of the overhead line, so as to calculate and obtain the tight line amount data of the current overhead line.

[0013] Further, the establishment process of the sag coordinate system includes:

[0014] First, use the measurement value at a certain position of the overhead line as the coordinate origin to establish a sag coordinate system; Perform pairwise coordinate calculations on the obtained measurement position information in a loop to obtain the coordinate positions of all measurement positions in the sag coordinate system;

[0015] The pairwise coordinate calculation is specifically as follows: Obtain two measurement points on the overhead line, one of the two measurement points is a known point, and the other is a measured point. Respectively, according to the pitch angle information of the laser ranging module corresponding to the two measurement points and the distance information of the laser point, measure the height values of the two measurement points according to the trigonometric relationship;

[0016] Calculate the distance between the two measurement points according to the rotation angle of the laser ranging module at these two measurement points, and according to the height values of these two measurement points, the relative coordinate distance of the abscissa of each point can be calculated through the Euclidean theorem, so as to obtain the abscissa information and ordinate information of the measured point in the sag coordinate system.

[0017] Furthermore, the fitting equation of the curve fitting is:

[0018]

[0019] In the formula, A, B, and C are all coefficients, x is the abscissa, and y is the ordinate.

[0020] Furthermore, the tensioning amount data of the current overhead line is calculated by comparing the sag values. The calculation process of the sag value includes:

[0021] Obtain two suspension points of the actual curve of the overhead line, connect the two suspension points, obtain the tangent line of the actual curve and the connection line of the two suspension points, and take the vertical distance between the tangent point corresponding to the tangent line and the connection line of the two suspension points as the sag value.

[0022] Furthermore, the calculation expression of the tensioning amount is:

[0023]

[0024] In the formula, l is the length of the strain section, l d is the representative span, l c is the observed span, f co is the measured sag, f c is the standard sag, is the height difference angle between the two suspension points, and Δl is the length of the tensioning.

[0025] Furthermore, the rotary platform mechanism includes a cradle-type rotary platform and a hollow rotary platform. The cradle-type rotary platform is connected to one side of the hollow rotary platform, and the laser ranging module is fixed on the cradle-type rotary platform;

[0026] In the fuzzy measurement step, by driving the cradle-type rotary platform and the hollow rotary platform to rotate respectively, the laser ranging module is driven to change the angle in the horizontal and vertical directions for measurement;

[0027] In the fine measurement step, within the fuzzy range, by fixing the cradle-type rotary platform so that the horizontal angle no longer changes, the hollow rotary platform is driven to drive the laser ranging module to change the angle in the vertical direction for measurement.

[0028] Further, during the measurement process, according to the angles of the cradle - type rotating platform and the hollow rotating platform, the horizontal and vertical coordinates of the laser point are obtained, and coordinate transformation is performed based on the distance of the laser point obtained by the laser ranging module to obtain the coordinate information of the laser point relative to the laser ranging module.

[0029] Further, the hollow rotating platform includes a vertical bearing, a first motor, a horizontal mounting plate, and a first housing that supports the entire hollow rotating platform. The vertical bearing is driven by the first motor, and both the vertical bearing and the cradle - type rotating platform are connected to the horizontal mounting plate, which is used to drive the cradle - type rotating platform to rotate in the horizontal direction.

[0030] Further, the cradle - type rotating platform includes a transverse bearing, a second motor, a ranging module mounting plate, and a second housing that supports the entire cradle - type rotating platform. The transverse bearing is driven by the second motor. One end of the ranging module mounting plate is rotatably connected to the second housing, and the other end is rotatably connected to the transverse bearing. The laser ranging module is fixed on the ranging module mounting plate and is used to rotate in the vertical direction through the drive of the second motor and rotate in the horizontal direction through the drive of the first motor.

[0031] Further, both the first motor and the second motor are servo motors.

[0032] Further, an anti - vibration displacement platform is provided between the rotating platform mechanism and the support platform. The anti - vibration displacement platform includes an anti - vibration displacement platform main body and a plurality of piezoelectric ceramic controllers. Each piezoelectric ceramic controller is fixed on the support platform, and the output end of each piezoelectric ceramic controller is connected to the anti - vibration displacement platform main body. The anti - vibration displacement platform main body performs horizontal pose adjustment under the control of each piezoelectric ceramic controller;

[0033] In the positioning step, according to the detection data of the universal inclination sensor, horizontal pose adjustment control is performed on each piezoelectric ceramic controller.

[0034] Further, the sag intelligent measurement and control device further includes a portable toolbox, which includes an industrial touch all - in - one computer, a mobile power supply, and a toolbox main body. The toolbox main body includes a plurality of placement areas for placing the industrial touch all - in - one computer, the mobile power supply, the laser ranging module, the rotating platform mechanism, and the anti - vibration displacement platform.

[0035] Further, the industrial touch all - in - one computer is communicatively connected to the universal inclination sensor and is used to display the device pose data. The adjustable support device includes a plurality of triangular support frames that are detachably connected to each other and are used to adjust the triangular support frames according to the device pose data.

[0036] Compared with the prior art, the present invention has the following advantages:

[0037] (1) The overhead line sag measurement method based on the integration of Beidou positioning and laser ranging provided by the present invention realizes the intelligent, digital, and automated high-precision detection of the sag of the target conductor, can improve the quality of sag detection, enhance the operation efficiency of tensioning wire construction in projects, reduce the labor cost of construction personnel, reduce the delay problem of the line construction period caused by the real environment, and promote the development and popularization of the power grid intelligent system.

[0038] (2) The laser ranging module of the present invention is fixed in position by a tooling fixture, and has the advantages of being portable, detachable, and easy to carry. When obtaining the coordinates of the overhead transmission line, the accuracy of the obtained coordinate points is directly related to the observed span. For different spans and the required measurement accuracy, the corresponding distance and accuracy can be adjusted by changing the laser ranging module to achieve the purpose of completing the test, avoiding the problem of excessive cost burden caused by replacing the whole set of equipment, and having a certain degree of flexibility, economy, and practicality.

[0039] (3) The vibration isolation displacement platform of the present invention is in a state of automatic leveling of the position and posture by a piezoelectric ceramic controller, ensuring the high-precision position and posture state of the equipment, avoiding the tilting of the device caused by the unevenness of the on-site operation ground, realizing the intelligent and automated real-time adjustment, and facilitating the development of automated measurement.

[0040] (4) The Beidou positioning module of the present invention has a high-precision positioning function, can realize the acquisition and application of real-time position coordinates, and can accurately calculate and locate the laser point coordinates in combination with the laser ranging module.

[0041] (5) The sag measurement device of the present invention has the characteristics of being intelligent, lightweight, and visual, and is convenient for movement and carrying. The device can automatically identify the wire target and measure, and replace humans to perform construction operations in related fields. It can also present a two-dimensional schematic diagram of the wire, intuitively reflecting the state of the measured overhead transmission line, and facilitating the improvement of the on-site construction efficiency and quality. Description of the Drawings

[0042] Figure 1 It is a schematic flow chart of an overhead line sag measurement method based on the integration of Beidou positioning and laser ranging provided in the embodiment of the present invention;

[0043] Figure 2 It is a schematic overall structure diagram of a sag intelligent measurement and control device provided in the embodiment of the present invention;

[0044] Figure 3 It is a schematic side view structure diagram of a sag intelligent measurement and control device provided in the embodiment of the present invention;

[0045] Figure 4 It is a schematic top view structure diagram of a sag intelligent measurement and control device provided in the embodiment of the present invention;

[0046] Figure 5 Schematic diagram of the rotating platform mechanism of a sag intelligent measurement and control device provided in an embodiment of the present invention;

[0047] Figure 6 Schematic diagram of the vibration isolation displacement platform of a sag intelligent measurement and control device provided in an embodiment of the present invention;

[0048] Figure 7 Schematic diagram of a portable toolbox of a sag intelligent measurement and control device provided in an embodiment of the present invention;

[0049] Figure 8 Sag schematic diagram provided in an embodiment of the present invention;

[0050] Figure 9 First schematic diagram of the three-dimensional space of an overhead line provided in an embodiment of the present invention;

[0051] Figure 10 Second schematic diagram of the three-dimensional space of an overhead line provided in an embodiment of the present invention;

[0052] In the figure, 1. Laser ranging module, 2. Tooling fixture, 3. Cradle-type rotating platform, 301. Second motor, 302. Ranging module mounting plate, 4. Adjustable support device, 5. Portable toolbox, 6. Industrial touch all-in-one computer, 7. Mobile power supply, 8. Beidou positioning device, 9. Hollow rotating platform, 901. First motor, 902. Horizontal mounting plate, 10. Piezoelectric ceramic controller, 11. Universal inclination sensor, 12. Support platform, 13. Vibration isolation displacement platform, 131. Vibration isolation displacement platform main body. Detailed implementation manners

[0053] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated herein can be arranged and designed in various different configurations.

[0054] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0055] It should be noted that like reference numerals and letters denote like items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0056] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the figures, or the orientation or positional relationship in which the inventive product is customarily placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the present invention.

[0057] It should be noted that the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, "a plurality" means two or more, unless otherwise specifically defined.

[0058] In addition, terms such as "horizontal" and "vertical" do not mean that the components are required to be absolutely horizontal or hanging vertically, but may be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but may be slightly inclined.

[0059] Embodiment 1

[0060] This embodiment provides an overhead line sag measurement method based on the fusion of Beidou positioning and laser ranging. This method measures the sag based on a sag intelligent measurement and control device, which will be specifically described below.

[0061] I. Sag intelligent measurement and control device

[0062] As Figure 2-4 shown, the sag intelligent measurement and control device includes a Beidou positioning device 8, a laser ranging module 1, a rotating platform mechanism, a vibration isolation displacement platform 13, a support platform 12, and an adjustable support device 4. The laser ranging module 1 is fixed on the rotating platform mechanism through a tooling fixture 2 and rotates in the horizontal and vertical directions under the drive of the rotating platform mechanism;

[0063] The rotating platform mechanism is connected to the vibration isolation displacement platform 13, bears the load of the vibration isolation displacement platform 13 and adjusts the horizontal pose. The vibration isolation displacement platform 13 is connected to the support platform 12 and bears the load of the support platform 12. The support platform 12 is installed on the adjustable support device 4. The Beidou positioning device 8 is connected to the support platform 12. The support platform 12 is also provided with a universal inclination sensor 11 for monitoring the pose data of the device.

[0064] As Figure 5 shown, the rotating platform mechanism includes a cradle-type rotating platform 3 and a hollow rotating platform 9. The cradle-type rotating platform 3 is connected to one side of the hollow rotating platform 9. The laser ranging module 1 is fixed on the cradle-type rotating platform 3 and is used to rotate in the horizontal direction through the hollow rotating platform 9 and rotate in the vertical direction through the cradle-type rotating platform 3.

[0065] The hollow rotating platform 9 includes a vertical bearing, a first motor 901, a horizontal mounting plate 902 and a first housing that supports the entire hollow rotating platform 9. The vertical bearing is driven by the first motor 901. Both the vertical bearing and the cradle-type rotating platform 3 are connected to the horizontal mounting plate 902 and are used to drive the cradle-type rotating platform 3 to rotate in the horizontal direction.

[0066] The cradle-type rotating platform 3 includes a transverse bearing, a second motor 301, a ranging module mounting plate 302 and a second housing that supports the entire cradle-type rotating platform 3. The transverse bearing is driven by the second motor 301. One end of the ranging module mounting plate 302 is rotatably connected to the second housing, and the other end is rotatably connected to the transverse bearing. The laser ranging module 1 is fixed on the ranging module mounting plate 302 and is used to rotate in the vertical direction through the drive of the second motor 301 and rotate in the horizontal direction through the drive of the first motor 901. Preferably, both the first motor 901 and the second motor 301 are servo motors to achieve fine control measurement.

[0067] The above structure realizes that the laser ranging module is fixed on the cradle-type rotating platform through a tooling fixture. The rotating platform mechanism is composed of a cradle-type rotating platform and a hollow rotating platform. Among them, the cradle-type rotating platform is driven by a servo motor to rotate around the transverse bearing in the vertical direction for high-precision vertical angle rotation and fine control measurement; the hollow rotating platform is driven by a servo motor to rotate around the vertical hollow bearing in the horizontal direction for high-precision horizontal angle rotation and fine control measurement. Through the mutual cooperation of the two platforms, precise control of horizontal and vertical angles and fine control measurement can be achieved.

[0068] As Figure 6As shown in the figure, the vibration isolation displacement platform 13 includes a vibration isolation displacement platform main body 131 and a plurality of piezoelectric ceramic controllers 10. Each piezoelectric ceramic controller 10 is fixed on the support platform 12, and the output end of each piezoelectric ceramic controller 10 is connected to the vibration isolation displacement platform main body 131. The vibration isolation displacement platform main body 131 performs horizontal pose adjustment under the control of each piezoelectric ceramic controller 10.

[0069] Equivalently, the rotation platform mechanism as a whole bears the laser ranging module and the tooling fixture and is fixed on the vibration isolation displacement platform. The vibration isolation displacement platform has the function of bearing the rotation platform mechanism, the tooling fixture and the laser ranging module, and can reduce the vibration influence of the on-site environment on the machine. The vibration isolation displacement platform is intelligently and automatically adjusted in real time by the piezoelectric ceramic controller so that the carried mechanism is always in a horizontal state in real time, which is convenient for obtaining coordinate points and data measurement.

[0070] The Beidou positioning device 8 is provided with an antenna module and a data transmission module. The Beidou positioning device 8 is controlled by a single-chip microcomputer and is used to obtain the coordinate and elevation information of the device.

[0071] The Beidou positioning device is controlled by a single-chip microcomputer and is fixed on the support platform in combination with an antenna module, a data transmission module, etc. The support platform bears all the above-mentioned mechanisms and is installed on an adjustable support device. The support platform is equipped with a universal inclination sensor, a Beidou positioning module and a piezoelectric ceramic controller. The universal inclination sensor monitors the pose of the device to facilitate the manual adjustment of the adjustable support device. The Beidou positioning is used to obtain the coordinate and elevation information of the device. The adjustable support device is composed of a triangular support frame, which plays a supporting role for the overall mechanism. The triangular support frame can be conveniently disassembled and installed and can be applied to the construction sites with different environments and operating grounds.

[0072] As Figure 7 shown, as a preferred implementation manner, the sag intelligent measurement and control device further includes a portable toolbox 5 including an industrial touch all-in-one computer 6, a mobile power supply 7 and a toolbox main body. The toolbox main body includes a plurality of placement areas for placing the industrial touch all-in-one computer 6, the mobile power supply 7, the laser ranging module 1, the rotation platform mechanism and the vibration isolation displacement platform 13.

[0073] The portable toolbox is made of high-strength materials that are pressure-proof and explosion-proof. It is internally equipped with an industrial touch all-in-one computer and a mobile power supply, and can place the laser ranging module and the entire mechanism part above the support platform. It can be carried and moved conveniently, and at the same time prevent the precision mechanisms from being bumped during handling and carrying, and play a protective role for each mechanism.

[0074] The industrial touch all-in-one machine 6 is communicatively connected to the universal tilt sensor 11 and is used to display the pose data of the device. The adjustable support device 4 includes a plurality of triangular support frames that are detachably connected to each other and is used to adjust the triangular support frames according to the device pose data.

[0075] II. Sag Measurement Method for Overhead Lines

[0076] As Figure 1 shown, the sag measurement method for overhead lines includes the following steps:

[0077] Positioning step S1: Place the sag intelligent measurement and control device on the side of the conductor of the overhead line or directly below the conductor suspension point. Expand the adjustable support device 4 and adjust the pose of the adjustable support device 4 according to the detection data of the universal tilt sensor so that the support platform 12 is in a horizontal state.

[0078] Specifically, according to the detection data of the universal tilt sensor, horizontal pose adjustment control is performed on each piezoelectric ceramic controller 10.

[0079] Fuzzy measurement step S2: Drive the laser ranging module 1 to change the angle through the rotating platform mechanism for measurement. When a laser feedback signal is obtained, record the position.

[0080] Fine measurement step S3: At each recorded position, drive the laser ranging module 1 to change the angle through the rotating platform mechanism for measurement. After obtaining the laser feedback signal, perform repeated measurement confirmation to obtain the position of the coordinate point at this time; according to the angle information of the device and the distance information of the laser point at this time, and combined with the real-time position coordinates of the Beidou positioning module, obtain the actual measurement value of the sag.

[0081] Specifically, in the fuzzy measurement step, drive the cradle-type rotating platform 3 and the hollow rotating platform 9 to rotate respectively, driving the laser ranging module 1 to change the angle in the horizontal and vertical directions for measurement.

[0082] In the fine measurement step, within the fuzzy range, fix the cradle-type rotating platform 3 so that the horizontal angle no longer changes, and drive the hollow rotating platform 9 to drive the laser ranging module 1 to change the angle in the vertical direction for measurement.

[0083] Monitoring step S4: Construct the actual curve of the overhead line according to the actual measurement value of the sag and compare it with the standard curve of the overhead line to realize the monitoring of the sag of the overhead line.

[0084] During the measurement process, according to the angles of the cradle-type rotating platform 3 and the hollow rotating platform 9, obtain the horizontal and vertical coordinates of the laser point, and perform coordinate transformation according to the distance of the laser point obtained by the laser ranging module to obtain the coordinate information of the laser point relative to the laser ranging module.

[0085] Specifically, the monitoring steps are as follows: An overhead line sag coordinate system is established based on the obtained actual measurement values of multiple sags. Curve fitting is performed under this overhead line sag coordinate system to obtain the actual curve of the overhead line. The actual curve of the overhead line is compared with the standard curve of the overhead line, so as to calculate and obtain the data of the tightening amount of the current overhead line.

[0086] Each step is specifically as follows:

[0087] 1. Positioning step S1

[0088] High-precision measurement of the overhead transmission line sag is carried out by using Beidou positioning and laser ranging technologies, providing an intelligent and automated measurement device for each technical department such as on-site wire tightening construction, wire inspection, and wire operation and maintenance to observe the wire, reducing the labor intensity and cost of manual operations, improving the construction work efficiency and quality, and ensuring that the sag meets the standard sag requirements in the wiring table.

[0089] The on-site positioning process of this embodiment is as follows. This embodiment uses a high-precision Beidou positioning module. By using the built-in single-chip microcomputer, data transmission module, and antenna, the real-time data of the three-dimensional coordinates and elevation of the device can be obtained, and the relative position coordinates are obtained through RTK differential positioning. When measuring, a position is selected first. The selection principle is that the overall mechanism of the device is placed on the side of the wire or directly below the wire suspension point, and the device is placed in an area with as wide a view as possible to reduce the problem that the laser point coordinates cannot be obtained due to the obstruction and occlusion of trees and buildings. After the device position is selected, the adjustable triangular support frame is manually unfolded, and the pose state of the device at the erection position is transmitted in real time via Bluetooth using a universal inclination sensor and presented on the industrial touch all-in-one computer, facilitating the operator to manually adjust the triangular support frame at any time to make the support platform mechanism within the qualified inclination range. Fix the telescopic length of the triangular support frame. After placing the sag measurement device at the selected position, the device automatically adjusts the vibration isolation displacement platform to the standard horizontal state according to the piezoelectric ceramic controller and monitors the pose state of the vibration isolation displacement platform in real time.

[0090] 2. Measurement step

[0091] After completing the selection of the measurement position points of the sag measurement device and implementing the erection, the sag of the overhead transmission line is measured;

[0092] This embodiment uses a rotating platform mechanism composed of a cradle-type rotating platform and a hollow rotating platform in conjunction with a laser ranging module to perform laser dotting on overhead transmission lines. Two servo motors control the two rotating platforms respectively, and the control system performs angle calculation and deceleration transmission in real time. In this process, the angle control is accurate to 5 seconds. During the high-precision rotation of the rotating platform, the laser ranging module adjusts the laser frequency through the control system to perform high-frequency laser dotting. During the laser dotting process, if the wire is accurately hit, the distance and horizontal and vertical angles from the point on the wire to the eyepiece of the laser rangefinder will be obtained. The data will be calculated to obtain the two-dimensional coordinates relative to the measurement position. The obtained data and the coordinates of the coordinate point are transmitted to the processor background via Bluetooth for storage and calculation. The measurement stage is divided into two parts.

[0093] S2: Fuzzy measurement

[0094] The sag measuring device control system controls the rotating platform mechanism and the laser ranging module to perform large-angle and high-frequency fuzzy measurements, which facilitates the device to quickly find the fuzzy range of the overhead transmission line. The motor drive is controlled by a fuzzy control strategy. When there is an excitation feedback signal, the position is recorded, thereby obtaining the fuzzy range of the overhead line and improving work efficiency.

[0095] S3: Fine Measurement

[0096] After obtaining the fuzzy range of the overhead line, it is necessary to further finely measure the two-dimensional coordinates of each specific laser point. At this time, the control system needs to read the position record information during the fuzzy measurement, adjust the rotating platform mechanism and the frequency of the laser ranging module for high-precision measurement, and when the laser angle is modulated to the vicinity of the recording position, the control system finely adjusts the laser angle through high-precision control and deceleration mechanism of the servo motor. At this time, the horizontal angle does not change, only the vertical angle is finely scanned. After obtaining the laser feedback information, repeat the measurement 3-5 times and record the position of the coordinate point at this time. The angle information of the device and the two-dimensional coordinates of the laser point are transmitted to the processor through the Bluetooth module for calculation. Similarly, when the laser angle is adjusted to the vicinity of the next recording position, the control system repeats the above operation to achieve high-precision measurement and storage of the laser point. The actual measurement value of the sag is obtained by calculation of the built-in software of the industrial touch all-in-one machine. At this point, the measurement stage is completed.

[0097] 3. Monitoring steps

[0098] In the above operations, the sag of the overhead transmission line in the actual situation is obtained. However, the ultimate goal is to guide on-site tensioning line construction, inspection, operation and maintenance, etc. The industrial touch all-in-one computer in the portable toolbox can present the 3D effect diagram of the actual curve model of the overhead transmission line after calculation and the 3D effect diagram of the standard overhead line, so as to intuitively see the coincidence degree between the two curves. By comparing the measured sag value with the standard sag value, the difference from the standard value can be obtained. Through the software calculation of the device of the present invention, the data of the amount of line tensioning required for the target overhead line can be obtained to guide on-site construction personnel to carry out the corresponding tensioning line construction and make the sag reach the standard value. In the line tensioning project, the rotary platform mechanism and the laser ranging module will perform a large-range scan through fuzzy measurement, and monitor the tensioning line situation of the overhead transmission line through the change of the two-dimensional image of the overhead transmission line, which is convenient for on-site identification and judgment.

[0099] Specifically, the process of establishing the sag coordinate system includes:

[0100] First, take the measurement value at a certain position of the overhead line as the coordinate origin to establish a sag coordinate system; perform pairwise coordinate calculations on the obtained measurement position information in a loop to obtain the coordinate positions of all measurement positions in the sag coordinate system;

[0101] The pairwise coordinate calculation is specifically as follows: Obtain two measurement points of the overhead line. One of the two measurement points is a known point, and the other is a measured point. According to the pitch angle information of the laser ranging module corresponding to the two measurement points and the distance information of the laser points respectively, and according to the triangular relationship, the height values of the two measurement points are measured;

[0102] According to the transformation angle of the laser ranging module under these two measurement points, calculate the distance between these two measurement points, and according to the height values of these two measurement points, through the Euclidean theorem, the relative coordinate distance of the abscissa of each point can be calculated, so as to obtain the abscissa information and ordinate information of the measured point in the sag coordinate system.

[0103] The data of the amount of line tensioning for the current overhead line is obtained by comparing the calculated sag values. The calculation process of the sag values includes:

[0104] Obtain two suspension points of the actual curve of the overhead line, connect the two suspension points, obtain the tangent line of the actual curve and the connection line of the two suspension points, and take the vertical distance between the tangent point corresponding to this tangent line and the connection line of the two suspension points as the sag value.

[0105] For the sag, the vertical distance from any point on the line connecting the two suspension points A and B of the wire to the overhead wire is called the sag of this point, that is Figure 8 where f. The standard sag given in the line tensioning construction is the vertical distance f between the tangent line A'B' of the overhead wire parallel to the line connecting the two suspension points A and B of the wire m f mAlso known as the observed sag of the span and the sag at the tangent point.

[0106] f m —— Observed sag value of the overhead conductor in the observed span (referring to the sag at the tangent point of the parallelogram), m;

[0107] f —— Sag value at any point of the initial overhead conductor, m. m is the unit of meter.

[0108] Overhead line sag measurement process:

[0109] First, select a location with good visibility and convenient for laser measurement to scan the sag in the initial state, and use the location of the laser rangefinder as the base point O.

[0110] 1. Identify the target overhead line, and use the laser rangefinder to continuously scan and mark points on the overhead transmission line within a certain angle range. When the line is hit, the distance value will be fed back. Repeat the operation two to three times. The purpose is to determine the angle range of the laser marking.

[0111] 2. Precise distance measurement. After the angle range is determined, in order to solve which line the laser specifically measures, judge according to the size of the distance value in sequence.

[0112] 3. Initial curve fitting. (1) Calculate the vertical distance, that is, the height information y, y1, y2 of each measurement point, through the corresponding relationship between the vertical angle and the distance. (2) Each measurement point is located within the plane of the overhead line. Figure 9 The following shows the schematic diagram of the three-dimensional space of the overhead line during measurement. First, the laser continuously marks points from one end. The closer to the lowest point, the denser the marking. A few points can be marked at the part close to the suspension point. Use the triangular relationship to obtain the heights y1, y2 corresponding to the measurement points S, S1, that is, take these values as the ordinate values of the catenary equation of the measurement points in this coordinate system.

[0113] 4. The abscissa values of the measurement points can be obtained according to Figure 9 and 10 the established coordinate system. Establish a coordinate system with A as the coordinate origin. Given y1, y2, d, use the Euclidean theorem to calculate the relative coordinate distances of each point x. Therefore, the x coordinates of the measured points can be obtained respectively. In addition, the relationship between the ranging distance and the rotation angle can be used to verify the accuracy of the x coordinate.

[0114] 5. Establish a mathematical model through the corresponding x and y coordinates, perform curve fitting, and obtain the curve equation. The fitting equation is as follows:

[0115]

[0116] Substitute the height of point A into the equation to obtain the position of point A on the curve equation. Based on the distance between points A and B on the drawing, find the position of point B in the curve equation. The fitting curve I need is the curve between A and B. Connect A and B, and by geometric means, find the tangent line of the curve and AB. The distance from the tangent point to the line connecting AB is the sag value.

[0117] Calculation of the tension adjustment amount:

[0118] Using the formula provided in this embodiment, substitute the measured sag and other parameters in the actual situation to obtain the specific value of the tension adjustment amount. The formula for the tension adjustment amount is:

[0119]

[0120] l —— length of the strain section, m;

[0121] l d —— representative span, m;

[0122] l c —— observed span, m;

[0123] f co —— measured sag, m;

[0124] f c —— standard sag (theoretical sag), m;

[0125] —— elevation angle difference between two suspension points.

[0126] Take the difference between the sag value and the standard sag, and input the sag change amount into the above formula to obtain the length Vl of the tension adjustment. This is convenient for guiding the efficient progress of the on-site construction tension adjustment process. It saves labor and avoids the risk of tower-assisted observation, contributing to the digital construction of the power system.

[0127] In this embodiment, reconstruct the curve for dozens of obtained coordinate points, present the actual curve form of the measured overhead line on an industrial touch all-in-one machine, and compare it with the pre-set standard curve form to visually reflect the deviation between the two curves. By using a series of formulas for calculation, the specific and accurate values that the operator needs to perform tension adjustment operations during the construction of the measured conductor can be obtained. After the construction is completed, measure the curve form after the operation by laser dotting again, and verify the measurement accuracy through standard comparison.

[0128] This solution provides intelligent and automated measurement devices for on-site overhead transmission line construction and subsequent inspection and operation and maintenance, promotes the research and development and popularization of technologies such as smart grids, intelligent inspection, and operation and maintenance, thus improving the technical support system and changing the traditional operation and maintenance mode.

[0129] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative efforts. Therefore, all technical solutions that can be obtained by those skilled in the art in the technical field based on the concept of the present invention through logical analysis, reasoning, or limited experiments on the basis of the prior art shall fall within the protection scope determined by the claims.

Claims

1. An overhead line sag measurement method based on the fusion of Beidou positioning and laser ranging, characterized in that, This method is based on the sag intelligent measurement and control device for sag measurement. The sag intelligent measurement and control device includes an adjustable support device (4), a support platform (12), and a Beidou positioning device (8), a laser ranging module (1) and a rotary platform mechanism installed on the support platform (12). The support platform (12) is installed on the adjustable support device (4). The Beidou positioning device (8) is connected to the support platform (12). The support platform (12) is also provided with a universal inclination sensor (11) for monitoring the device pose data; The method includes the following steps: Positioning step: Place the sag intelligent measurement and control device directly below the overhead line, unfold the adjustable support device (4), and adjust the pose of the adjustable support device (4) according to the detection data of the universal inclination sensor so that the support platform (12) is in a horizontal state; Fuzzy measurement step: The rotary platform mechanism includes a cradle-type rotary platform (3) and a hollow rotary platform (9). The cradle-type rotary platform (3) is connected to one side of the hollow rotary platform (9). The laser ranging module (1) is fixed on the cradle-type rotary platform (3); Drive the laser ranging module (1) to change the angle within a preset initial angle range for measurement through the rotary platform mechanism. When a laser feedback signal is obtained, record the position and determine the laser dotting angle range of the current feedback position; Fine measurement step: At each feedback position, drive the laser ranging module (1) to change the angle within the corresponding laser dotting angle range for measurement through the rotary platform mechanism. After obtaining the laser feedback signal, perform repeated measurement confirmation to obtain the position of the coordinate point at this time; According to the angle information of the device and the distance information of the laser point at this time, and combined with the real-time position coordinates of the Beidou positioning module, obtain the actual measurement value of the sag; Monitoring step: Construct the actual curve of the overhead line according to the actual measurement value of the sag, and compare it with the standard curve of the overhead line to calculate the tight line amount data of the current overhead line; The monitoring step is specifically as follows: Establish a sag coordinate system according to the obtained actual measurement values of multiple sags, perform curve fitting under this sag coordinate system to obtain the actual curve of the overhead line; Compare the actual curve of this overhead line with the standard curve of the overhead line, so as to calculate and obtain the tight line amount data of the current overhead line; The establishment process of the sag coordinate system includes: First, use the measurement value at a certain position of the overhead line as the coordinate origin to establish a sag coordinate system; Perform pairwise coordinate calculations on the obtained measurement position information in a loop to obtain the coordinate positions of all measurement positions under the sag coordinate system; The pairwise coordinate calculation is specifically as follows: Obtain two measurement points on the overhead line. One of the two measurement points is a known point and the other is a measured point. Respectively, according to the pitch angle information of the laser ranging module corresponding to the two measurement points and the distance information of the laser point, measure the height values of the two measurement points according to the trigonometric relationship; Calculate the distance between these two measurement points based on the transformation angles of the laser ranging module at these two measurement points, and according to the height values of these two measurement points, the relative coordinate distances of the abscissas of each point can be calculated through the Euclidean theorem, so as to obtain the abscissa information and ordinate information of the measured point in the sag coordinate system; The calculation process of the tight line amount data includes: obtaining two suspension points of the actual curve of the overhead line, connecting the two suspension points, obtaining the tangent of the actual curve and the line connecting the two suspension points, and taking the vertical distance between the tangent point corresponding to the tangent and the line connecting the two suspension points as the measured sag; The calculation expression of the tight line amount is: Wherein, l is the length of the strain section, l d is the representative span, l c is the observed span, f co is the measured sag, f c is the standard sag, is the elevation angle between two suspension points, and Δl is the length of the tight line.

2. The method for measuring the sag of overhead lines based on the fusion of Beidou positioning and laser ranging according to claim 1, wherein The fitting equation of the curve fitting is: In the formula, A, B, and C are all coefficients, x is the abscissa, and y is the ordinate.

3. A sag measurement method for overhead lines based on the fusion of Beidou positioning and laser ranging according to claim 1, characterized in that, In the fuzzy measurement step, by driving the cradle-type rotating platform (3) and the hollow rotating platform (9) to rotate respectively, the laser ranging module (1) is driven to change the angle in the horizontal and vertical directions for measurement; In the fine measurement step, within the laser marking angle range, by fixing the cradle-type rotating platform (3) to make the horizontal angle no longer change, the hollow rotating platform (9) is driven to drive the laser ranging module (1) to change the angle in the vertical direction for measurement.

4. A method for measuring the sag of overhead lines based on the fusion of Beidou positioning and laser ranging according to claim 3, characterized in that During the measurement process, according to the angles of the cradle-type rotating platform (3) and the hollow rotating platform (9), the horizontal coordinates and vertical coordinates of the laser point are obtained, and coordinate transformation is performed according to the distance of the laser point obtained by the laser ranging module to obtain the coordinate information of the laser point relative to the laser ranging module.

5. The sag measurement method for overhead lines based on the fusion of Beidou positioning and laser ranging according to claim 4, wherein, The hollow rotating platform (9) includes a vertical bearing, a first motor (901), a horizontal mounting plate (902), and a first housing supporting the entire hollow rotating platform (9). The vertical bearing is driven by the first motor (901), and both the vertical bearing and the cradle-type rotating platform (3) are connected to the horizontal mounting plate (902) for driving the cradle-type rotating platform (3) to rotate in the horizontal direction; The cradle-type rotating platform (3) includes a transverse bearing, a second motor (301), a ranging module mounting plate (302), and a second housing supporting the entire cradle-type rotating platform (3). The transverse bearing is driven by the second motor (301). One end of the ranging module mounting plate (302) is rotatably connected to the second housing, and the other end is rotatably connected to the transverse bearing. The laser ranging module (1) is fixed on the ranging module mounting plate (302) and is used to be driven by the second motor (301) to rotate in the vertical direction; and to rotate in the horizontal direction by being driven by the first motor (901).

6. The method for measuring the sag of overhead lines based on the fusion of Beidou positioning and laser ranging according to claim 1, wherein, An anti-vibration displacement platform (13) is provided between the rotating platform mechanism and the support platform (12). The anti-vibration displacement platform (13) includes an anti-vibration displacement platform main body (131) and a plurality of piezoelectric ceramic controllers (10). Each piezoelectric ceramic controller (10) is fixed on the support platform (12), and the output end of each piezoelectric ceramic controller (10) is connected to the anti-vibration displacement platform main body (131). The anti-vibration displacement platform main body (131) performs horizontal pose adjustment under the control of each piezoelectric ceramic controller (10); In the positioning step, according to the detection data of the gimbal inclination sensor, the horizontal pose adjustment control is performed on each piezoelectric ceramic controller (10).

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