An aerial cable-to-ground distance measuring device

Abstract

The utility model discloses an overhead cable distance to ground measuring device includes at least one distance to ground measuring unit and a host computer. Each distance to ground measuring unit is installed at each cable monitoring point of overhead cable respectively, and the host computer is installed in the monitoring room. Each distance to ground measuring unit includes insulating shell, metal shield, 2 fixed buckle, solar cell panel, battery, millimeter wave radar sensor, three -axis acceleration sensor and control circuit board. The distance to ground measuring unit of coaxial integration makes millimeter wave radar beam's visual axis and accelerometer sensitive axle forcedly share same geometry reference, and the measurement value of swing angle can be directly mapped as beam direction angle, and need not additional space coordinate transformation matrix, and high -precision swing compensation can be realized without adjusting flat, and calibration, realizes overhead cable distance to ground measurement, and realizes accurate measurement of measurement error under the condition of cable swing, and the whole operation is automatic.

Description

Technical Field

[0001] This utility model relates to the field of overhead cable technology, and specifically to an overhead cable-to-ground distance measuring device. Background Technology

[0002] Overhead cables are a method of transmitting electricity or communication by suspending conductors in the air. They mainly consist of conductors, insulators, and towers. Overhead cables are exposed to the air for extended periods, making them susceptible to damage from natural environmental factors such as wind, rain, and lightning, as well as external forces. Since overhead cables are mostly laid in open terrain with few obstacles, it is difficult for workers to conduct on-site maintenance. Therefore, current methods utilize ground distance measuring devices installed on overhead cables for remote monitoring. When the ground distance measuring device detects that the distance between the overhead cable and the ground exceeds a preset range, it indicates that the overhead cable may be damaged and on-site maintenance is required. However, existing overhead cable ground distance measuring devices use a method of directly fixing a lidar sensor to the cable and assuming the cable is stationary to measure the distance to the ground. This has the following shortcomings: 1) Large measurement error: Traditional ground distance measuring devices ignore the swaying of overhead cables caused by wind or temperature changes, resulting in a measurement error of 20-40 centimeters, which is insufficient for accurate monitoring. 2) Poor dynamic adaptability: Traditional ground distance measuring devices lack a real-time compensation mechanism for cable swing, and the measurement results cannot reflect the dynamic changes of the cable, which can easily lead to safety hazards. Utility Model Content

[0003] The present invention addresses the problem that existing overhead cable distance measurement devices cannot meet the requirements for accurate monitoring, and provides an overhead cable distance measurement device.

[0004] To solve the above problems, this utility model is achieved through the following technical solution:

[0005] An overhead cable ground distance measuring device includes at least one ground distance measuring unit and a host computer. Each ground distance measuring unit is installed at a monitoring point of the overhead cable, while the host computer is installed in a monitoring room. Each ground distance measuring unit is communicatively connected to the host computer.

[0006] Each ground distance measurement unit includes an insulating shell, a metal shield, two fixing clips, a solar panel, a battery, a millimeter-wave radar sensor, a triaxial accelerometer, and a control circuit board. Both the insulating shell and the metal shield are regular cylindrical hollow bodies. The insulating shell is nested outside the metal shield, with their longitudinal axes completely overlapping. A signal radiation window is located on the bottom surface of both the insulating shell and the metal shield at opposite positions, with the center point of the two signal radiation windows located on the longitudinal axis of the insulating shell. The two fixing clips are respectively fixed to opposite surfaces of the outer wall of the insulating shell, and the line connecting the two fixing clips is perpendicular to and intersects the longitudinal axis of the insulating shell.

[0007] A solar panel covers the top surface of an insulating outer casing. The battery is located inside the insulating casing, outside a metal shield. The normals of the solar panel and battery coincide with the longitudinal axis of the insulating casing. A millimeter-wave radar sensor, a triaxial accelerometer, and a control circuit board are all mounted inside the metal shield. The normal of the millimeter-wave radar sensor coincides with the longitudinal axis of the metal shield, and the sensor is directly opposite the two signal radiation windows. The origin of the triaxial accelerometer's sensing direction is located on the longitudinal axis of the metal shield; the Z-axis sensing direction coincides with the longitudinal axis of the metal shield, while the X-axis and Y-axis sensing directions are perpendicular to the longitudinal axis of the metal shield. The normal of the control circuit board coincides with the longitudinal axis of the metal shield.

[0008] The control circuit board houses a power module, a microcontroller, and a communication module. The output of the solar panel is connected to the input of the battery, the output of the battery is connected to the input of the power module, and the output of the power module is connected to the microcontroller and communication module within the control circuit board, as well as to the millimeter-wave radar sensor and triaxial accelerometer outside the control circuit board. The outputs of the millimeter-wave radar sensor and triaxial accelerometer are connected to the data input of the microcontroller, and the communication module is connected to the communication terminal of the microcontroller.

[0009] The aforementioned millimeter-wave radar sensor is a 60GHz frequency-modulated continuous wave millimeter-wave radar sensor, the triaxial accelerometer is a MEMS triaxial accelerometer, and the microcontroller is an STM32H743 microcontroller.

[0010] Compared with existing technologies, this invention achieves coaxial integration of the ground distance measurement unit through a special design of the structure and installation method of each component. This ensures that the line of sight of the millimeter-wave radar beam and the sensitive axis of the accelerometer share the same geometric reference, and the measured value of the sway angle can be directly mapped to the beam direction angle without the need for an additional spatial coordinate transformation matrix, achieving high-precision sway compensation without leveling or calibration. Even in complex environments such as rain, fog, strong winds, and nighttime, it can still achieve continuous, accurate, and non-contact measurement of the sag of overhead cables and the clearance height of roads or passageways below them, achieving a measurement error of ≤±3 cm even under cable sway conditions. The entire operation is automated, requiring no manual intervention, thereby improving the operational safety and maintenance efficiency of various overhead cables. This invention is applicable to, but is not limited to, ADSS / OPGW communication optical cables, high-voltage transmission lines, overhead ground wires, and other suspended cables. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the principle structure of a ground distance measuring unit of an overhead cable ground distance measuring device.

[0012] The following components are labeled in the diagram: 1. Insulating shell, 2. Metal shielding cover, 3. Fixing clip, 4. Solar panel, 5. Battery, 6. Millimeter-wave radar sensor, 7. Triaxial accelerometer, 8. Control circuit board, 9. Overhead cable. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of this utility model clearer, the following detailed description is provided in conjunction with specific examples and the accompanying drawings. It should be noted that directional terms mentioned in the examples, such as "up," "down," "middle," "left," "right," "front," and "back," are only for reference to the directions in the accompanying drawings. Therefore, the directions used are for illustrative purposes only and are not intended to limit the scope of protection of this utility model.

[0014] Considering that in actual operation, the overhead cable 9 will experience instantaneous swaying of 5° to 25° due to wind, temperature differences, or passing vehicles, resulting in a non-negligible beam cosine error and ranging drift often reaching 30 to 50 cm, which easily triggers false alarms or missed alarms, this utility model proposes an overhead cable 9 ground distance measuring device, which mainly consists of at least one ground distance measuring unit and a host computer. Each ground distance measuring unit is installed at each cable monitoring point of the overhead cable 9, and the host computer is installed in the monitoring room. Each ground distance measuring unit is communicatively connected to the host computer.

[0015] To achieve accurate measurement of the distance to ground under cable swaying conditions, the ground distance measurement unit adopts a coaxial integrated structure design. It mainly consists of an insulating shell 1, a metal shield 2, two fixing clips 3, a solar panel 4, a battery 5, a millimeter-wave radar sensor 6, a triaxial accelerometer 7, and a control circuit board 8. Figure 1 As shown.

[0016] Both the insulating outer shell 1 and the metal shielding cover 2 are regular cylindrical hollow bodies. The insulating outer shell 1 is nested outside the metal shielding cover 2, and their longitudinal central axes are completely coincident. A signal radiation window is opened at a relatively opposite position on the bottom surface of both the insulating outer shell 1 and the metal shielding cover 2, and the center point of the two signal radiation windows is located on the longitudinal central axis of the insulating outer shell 1. Two fixing clips 3 are respectively fixed to the opposite surfaces of the outer wall of the insulating outer shell 1, and the line connecting the two fixing clips 3 is perpendicular to and intersects the longitudinal central axis of the insulating outer shell 1. A solar panel 4 covers the top surface of the insulating outer shell 1. The battery 5 is located inside the insulating outer shell 1, outside the metal shielding cover 2. In this embodiment, the insulating shell 1 is made of materials such as PC and ABS to provide overall protection for the distance to ground measurement unit and extend the durability of the device; the metal shield 2 is made of metal materials such as iron, aluminum, and copper to shield the electromagnetic interference of external signals to the distance to ground measurement unit and improve the detection accuracy of the device; the fixing buckle 3 is an elastic open ring that can be directly clipped onto the outer sheath of the overhead cable 9 to achieve quick installation of the device.

[0017] The normals of solar panel 4 and battery 5 coincide with the longitudinal central axis of insulating casing 1. Millimeter-wave radar sensor 6, triaxial accelerometer 7, and control circuit board 8 are all mounted inside metal shield 2. The normal of millimeter-wave radar sensor 6 coincides with the longitudinal central axis of metal shield 2, and millimeter-wave radar sensor 6 is directly opposite the two signal radiation windows. The origin of the sensitive direction of triaxial accelerometer 7 is located on the longitudinal central axis of metal shield 2; its Z-axis sensitive direction coincides with the longitudinal central axis of metal shield 2, and its X-axis and Y-axis sensitive directions are perpendicular to the longitudinal central axis of metal shield 2. The normal of control circuit board 8 coincides with the longitudinal central axis of metal shield 2.

[0018] The control circuit board 8 houses a power module, a microcontroller, and a communication module. The output of the solar panel 4 is connected to the input of the battery 5, the output of the battery 5 is connected to the input of the power module, and the output of the power module is connected to the microcontroller and communication module within the control circuit board 8, as well as to the millimeter-wave radar sensor 6 and the triaxial accelerometer 7 outside the control circuit board 8. The outputs of the millimeter-wave radar sensor 6 and the triaxial accelerometer 7 are connected to the data input of the microcontroller, and the communication module is connected to the communication terminal of the microcontroller. In this embodiment, the millimeter-wave radar sensor 6 is a 60GHz frequency-modulated continuous wave (FMCW) millimeter-wave radar sensor, with a ranging accuracy of ±1cm. The triaxial accelerometer 7 is a MEMS triaxial accelerometer sensor, with an angular resolution of ±0.1°. In this embodiment, the microcontroller is an STM32H743 microcontroller, capable of achieving 400MIPS real-time processing capability.

[0019] The ground distance measurement unit is the core component of this invention. It adopts a coaxial integrated structure design to ensure that the line of sight of the millimeter-wave radar beam of the millimeter-wave radar sensor 6 and the sensitive axis of the triaxial accelerometer 7 share the same geometric reference. Because the line of sight of the millimeter-wave radar beam of the millimeter-wave radar sensor 6 and the sensitive axis of the triaxial accelerometer 7 share the same geometric reference, the measured value of the swing angle can be directly mapped to the beam direction angle without the need for an additional spatial coordinate transformation matrix. High-precision swing compensation can be achieved without leveling or calibration. Its specific working process is as follows:

[0020] 1) The "angle-error" correction table, which reflects the correspondence between the cable swing angle and the measurement error and is obtained through experiments in advance, is stored in the built-in memory of the microcontroller of each distance measurement unit.

[0021] 2) Install the ground distance measurement unit at the monitoring point of the corresponding overhead cable 9. During installation, fix the two solid clips 3 of the ground distance measurement unit to the overhead cable 9, and make the X-axis sensitive direction of the triaxial accelerometer 7 parallel to the direction of the line connecting the two solid clips 3.

[0022] 3) The triaxial accelerometer 7 collects the cable swing angles θ and φ in real time and sends them to the microcontroller. θ represents the Y-axis angle, and φ represents the Z-axis angle.

[0023] 4) The microcontroller obtains the error distance ΔL by querying the "angle-error" correction table stored in its internal database based on the collected cable swing angles θ and φ.

[0024] 5) The millimeter-wave radar sensor 6 collects the original ranging distance Lraw of the cable in real time and sends the original ranging distance Lraw into the microcontroller.

[0025] 6) The microcontroller uses the error distance ΔL obtained from the lookup table to compensate for the original ranging distance Lraw, and obtains the corrected ground distance Lcorr, that is, Lcorr=Lraw-ΔL.

[0026] 7) The microcontroller uploads the corrected ground distance Lcorr to the host computer through the communication module. The host computer determines whether the ground distance Lcorr of the cable at the monitoring point where the ground distance measurement unit is located exceeds the preset safety value based on the corrected ground distance Lcorr uploaded by the ground distance measurement unit. Once the preset safety value is exceeded, an alarm is issued to prompt the worker to go to the site for inspection.

[0027] It should be noted that although the embodiments described above are illustrative, they are not intended to limit the present invention. Therefore, the present invention is not limited to the specific embodiments described above. Any other embodiments obtained by those skilled in the art under the guidance of the present invention without departing from its principles are considered to be within the protection scope of the present invention.

Claims

1. A device for measuring the distance to ground of an overhead cable (9), comprising at least one distance measurement unit and a host computer; each distance measurement unit is installed at a monitoring point of the overhead cable (9), and the host computer is installed in a monitoring room; each distance measurement unit is communicatively connected to the host computer; characterized in that, Each ground distance measurement unit includes an insulating shell (1), a metal shield (2), two fixing clips (3), a solar panel (4), a battery (5), a millimeter-wave radar sensor (6), a triaxial accelerometer (7), and a control circuit board (8); the insulating shell (1) and the metal shield (2) are both regular columnar hollow bodies; the insulating shell (1) is nested outside the metal shield (2), and the longitudinal central axes of the two are completely coincident; a signal radiation window is opened at the opposite position of the bottom surface of the insulating shell (1) and the metal shield (2), and the center point of the two signal radiation windows is located on the longitudinal central axis of the insulating shell (1); the two fixing clips (3) are respectively fixed to the opposite surface of the outer wall of the insulating shell (1), and the line connecting the two fixing clips (3) is perpendicular to and intersects the longitudinal central axis of the insulating shell (1); A solar panel (4) is placed on the top surface of an insulating shell (1); a battery (5) is placed inside the insulating shell (1) and outside the metal shield (2); the normals of the solar panel (4) and the battery (5) coincide with the longitudinal central axis of the insulating shell (1); a millimeter-wave radar sensor (6), a triaxial accelerometer (7), and a control circuit board (8) are all installed inside the metal shield (2); the normal of the millimeter-wave radar sensor (6) coincides with the longitudinal central axis of the metal shield (2), and the millimeter-wave radar sensor (6) is directly opposite the two signal radiation windows; the origin of the sensitive direction of the triaxial accelerometer (7) is located on the longitudinal central axis of the metal shield (2), the Z-axis sensitive direction coincides with the longitudinal central axis of the metal shield (2), and the X-axis and Y-axis sensitive directions are perpendicular to the longitudinal central axis of the metal shield (2); the normal of the control circuit board (8) coincides with the longitudinal central axis of the metal shield (2). The control circuit board (8) contains a power module, a microcontroller, and a communication module; the output end of the solar panel (4) is connected to the input end of the battery (5), the output end of the battery (5) is connected to the input end of the power module, the output end of the power module is connected to the microcontroller and communication module inside the control circuit board (8), as well as the millimeter-wave radar sensor (6) and the triaxial accelerometer (7) outside the control circuit board (8); the output ends of the millimeter-wave radar sensor (6) and the triaxial accelerometer (7) are connected to the data input end of the microcontroller, and the communication module is connected to the communication end of the microcontroller.

2. The overhead cable (9) ground distance measuring device according to claim 1, characterized in that, The millimeter-wave radar sensor (6) is a 60GHz frequency modulated continuous wave millimeter-wave radar sensor (6), and the triaxial accelerometer (7) is a MEMS triaxial accelerometer (7).

3. The overhead cable (9) ground distance measuring device according to claim 1, characterized in that, The microcontroller is an STM32H743 microcontroller.

Images