UAV-based Real-time Detection System for Overhead Transmission Line Channels and Its Detection Method

Abstract

The present invention provides a real-time detection system for overhead transmission line channels based on unmanned aerial vehicles and a detection method thereof, including: an unmanned aerial vehicle flight platform, a ground control unit, and multiple groups of height beacon reflectors; after measuring the three-dimensional data of the wire and environmental parameters through lidar, performing downsampling of the point cloud, and then providing a height compensation value through the height beacon reflectors to reduce the theoretical calculation error, performing a logical operation on the measured value and the theoretical value, and finally obtaining a high-precision determination result. The invention does not introduce complex three-dimensional contrast calculations with high-definition environmental pictures and adopts a unique method of two determination rules, greatly making up for the deficiency of frame loss when collecting wires by laser ranging; further reducing the heat generation of the chip and equipment, prolonging the service life of the entire system, and having lower power consumption and manufacturing costs than existing technology products, which is suitable for popularization.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicle (UAV) detection and intelligent processing systems, and in particular to a real-time detection system for overhead transmission line channels based on UAVs and a detection method thereof. Background Art

[0002] Compared with underground transmission lines, overhead transmission lines have low construction costs, short construction periods, and are easy to repair and maintain. Therefore, overhead line transmission is the main transmission method adopted since the development of the power industry; the so-called transmission lines usually refer to overhead transmission lines, which connect power stations, substations, and load points in different regions through overhead lines to transmit or exchange electric energy, forming power networks of various voltage levels.

[0003] Since overhead lines are exposed to the atmospheric environment, they are directly affected by meteorological conditions and the external environment, so transmission failures often occur in power transmission. These failures are mainly as follows:

[0004] ① Single-phase grounding fault:

[0005] It mostly occurs in rainy and humid climates and is caused by factors such as single-phase breakdown of insulators on transmission lines, overload burnout or oxidation and corrosion peeling at wire joints, and single-phase wire breakage.

[0006] ② External force damage fault:

[0007] It is mainly manifested as wire scraping during the driving of ultra-high vehicles or foreign objects blown by strong winds getting caught on the wire.

[0008] ③ Bird damage fault:

[0009] Mostly caused by birds building nests, resulting in phase-to-phase short circuits.

[0010] ④ Risk of wire sag colliding with obstacles:

[0011] After the wires between power towers are connected, due to their own gravity, the wire sag between power towers is likely to cause the risk of colliding with houses and trees on the ground.

[0012] In order to timely detect and handle the above-mentioned overhead transmission line faults and maintain the overall stability and safety of the power transmission system, power companies usually set up an inspection mechanism for overhead transmission lines. Through regular inspections, the occurrence of power transmission accidents is reduced; especially the problem of the risk of wire sag colliding with possible obstacles in the environment is the main content to be inspected during inspections. Because for other breakpoints and wire drops, the monitoring platform will actively detect power transmission faults, while this predictive situation of the risk of wire sag colliding with obstacles cannot be detected by the monitoring background; in the prior art, the inspection methods for overhead lines mainly include: manual inspection, intelligent robot inspection, manned aircraft inspection, and UAV inspection.

[0013] Manual inspection method: Since overhead transmission lines are mostly set among mountains and ridges with harsh environments, the manual inspection method has excessive labor intensity, a relatively high risk factor, and a long inspection cycle. When encountering a relatively complex terrain environment, it is difficult to complete the inspection task according to the standards.

[0014] Intelligent robot inspection method: This method is suitable for the inspection of urban overhead transmission lines with relatively mild environments and is not suitable for inspecting wild environments such as across mountains, swamps, and lakes. The operation range is very limited.

[0015] Manned aircraft inspection: Currently, most inspections of overhead transmission lines are carried out by helicopters carrying inspection personnel. Through methods such as taking pictures, recording videos, and visual observation, defect verification is carried out. This inspection method highly relies on the experience and ability of inspection personnel, has low detection accuracy, and often lags behind the accident for a period of time during later verification, lacking real-time performance.

[0016] UAV inspection: Through the comparison of collected pictures, real-time identification of faults and potential hazards is achieved. However, the existing UAV inspection systems cannot accurately identify the wire sag clearly. Although it is better than the early manual inspection, due to the uneven ground, easy distortion of image data processing, etc., it is impossible to accurately locate and calculate the accurate value of the wire sag, and thus it is impossible to form an accurate pre-judgment.

[0017] UAVs cannot perform precise wire sag calculations through simple image acquisition. After combining with laser ranging, using laser ranging as the base map and taking real-scene photos for three-dimensional real-scene information, and performing three-dimensional reconstruction calculations by fusing the point cloud data of a large number of taken pictures with the vector data after laser ranging, it will also lead to low robustness of the calculation system due to the introduction of complex high-definition environmental images and environmental noise interference, resulting in a large number of calculation deviations; moreover, this method has a large amount of calculation, has extremely high requirements for chips and battery power, and is not suitable for the UAV inspection needs in a large-scale working environment; in actual use, due to the thin wires, there will be frame loss during data acquisition when performing laser ranging, so it is also impossible to accurately and synchronously integrate the three-dimensional real scene into the laser ranging base map coordinates, and the processing results are inaccurate.

[0018] With the development of lidar ranging technology, small, high-precision, point-to-plane and other lidar with comprehensive performance have been widely used. However, the complex wild environment, the uneven ground between high and low wire towers, and the covering of vegetation such as trees and shrubs all affect the accurate acquisition of vector values during ranging, and the numerical changes of the reference objects cause inaccurate laser ranging. Summary of the Invention

[0019] In order to overcome the deficiencies of the prior art, the present invention provides a real-time detection system and method for overhead transmission line channels based on drones. After measuring the three-dimensional data of the wire and environmental parameters through lidar, thinning the point cloud is performed, and then through a height beacon reflector, a height compensation value is provided to reduce the theoretical calculation error. The measured value and the theoretical value are subjected to a logical operation, and finally a highly accurate determination result is obtained. The invention does not introduce complex three-dimensional contrast calculations using high-definition environmental images, and adopts a unique processing method of two determination rules combined with logical operations, greatly making up for the deficiency of frame loss when collecting wires by laser ranging.

[0020] A real-time detection system and method for overhead transmission line channels based on drones, wherein:

[0021] A real-time detection system for overhead transmission line channels based on drones includes: a drone flight platform, a ground control unit, and multiple groups of height beacon reflectors;

[0022] The drone flight platform includes: a drone body, and a lidar acquisition unit, a thermal imaging measurement unit, and a position sensor provided on the drone body;

[0023] As an example, the drone body adopts: a drone with vertical takeoff and landing of rotors and fixed-wing cruising;

[0024] As an example, the lidar acquisition unit adopts a lidar rangefinder for real-time acquisition of wire, height beacon reflector, and environmental parameter data;

[0025] As an example, the thermal imaging measurement unit is used for: assisting in determining whether there is a short circuit or open circuit in the wire, and real-time feedback of the measurement result to the ground control unit;

[0026] As an example, the position sensor adopts: a high-precision position sensor; for synchronizing the position coordinates with the height beacon reflector.

[0027] The ground control unit includes: a drone flight platform control unit, a lidar data processing unit, a height beacon reflector storage unit, and a logical operation unit;

[0028] The drone flight platform control unit is used for: flight instruction control of the drone body, acquisition instruction control of the lidar acquisition unit, measurement instruction control of the thermal imaging measurement unit, and coordinate calibration instruction control of the position sensor;

[0029] The lidar data processing unit is used to: process the data collected by the lidar acquisition unit, and perform thinning point cloud processing on the three-dimensional data of each actual wire and the ground environment in real time, and actually determine whether there is a measured collision risk between the sag of each wire and obstacles;

[0030] The height beacon reflector storage unit is used to: pre-store the measured coordinates and measured height values of each group of height beacon reflectors, and perform co-location coordinate calibration with the lidar data processing unit in real time. For the points with the same coordinate position as the height beacon reflector, perform a difference operation on the height value of the height beacon reflector measured during the inspection by the lidar acquisition unit and the pre-stored measured height value to obtain a compensation value;

[0031] The logic operation unit is used to: calculate and output whether there is a collision risk between the sag of each wire and the environment. The calculation and determination rules include:

[0032] ① After introducing the compensation value through the parameters of the wire, calculate the theoretical sag values of each point of each wire in real time;

[0033] As an example, the parameters of the wire include: wire material, environmental temperature, environmental humidity, and the height of the power transmission towers connected at both ends of the wire, etc.

[0034] As an example, parameters such as the environmental temperature and humidity can be provided to the logic operation unit in real time by the induction device carried by the UAV body.

[0035] ② After ensuring the accuracy of the theoretical sag values of each point of each wire by introducing the compensation value, incorporate the theoretical sag values of each point into the corresponding three-dimensional data that has been collected and the measured wire parameters have been removed, and perform thinning point cloud processing again to secondarily determine whether there is a theoretical collision risk between the sag of each wire and obstacles;

[0036] As an example, the theoretical sag values of each point can be determined by equidistant sampling or random sampling after setting a fixed number of sampling values for each wire.

[0037] As an example, each wire refers to the wire connected between two adjacent power transmission towers;

[0038] ③ Perform a logical "AND" operation on the measured collision risk data value of each wire and its corresponding theoretical collision risk data value to obtain whether there is a warning of collision risk between the wire sag and the environment, that is:

[0039] When: both the measured collision risk data value and the theoretical collision risk data value are at risk, then the logic operation unit determines that there is a collision risk between the wire sag and the environment;

[0040] When both the measured collision risk data value and the theoretical collision risk data value are risk-free, the logic operation unit determines that there is no risk of wire sag colliding with the environment;

[0041] When either the measured collision risk data value or the theoretical collision risk data value is risky, the logic operation unit determines that there is a risk of wire sag colliding with the environment;

[0042] The height beacon reflector: uses a glass prism reflector. Since the glass prism reflector can easily reflect the laser ranging signal, it is easy to determine its own position information and height information; Each group of height beacon reflectors is installed at the lap joint of each wire and the insulator of the electric tower.

[0043] As an example, the height beacon reflector only needs to be installed at the lap joint of the lowest wire between each electric tower and the insulator of the electric tower.

[0044] The detection method of the real-time detection system for overhead transmission line channels based on an unmanned aerial vehicle includes:

[0045] Step 1, parameter measurement and storage of each group of height beacon reflectors: Use a handheld high-precision position sensor combined with a laser rangefinder to collect the coordinate parameters and height values of each group of height beacon reflectors; and synchronously send them to the height beacon reflector storage unit; Each group of height beacon reflectors is installed at the lap joint of each wire and the insulator of the electric tower.

[0046] As an example, the handheld high-precision position sensor and the position sensor on the unmanned aerial vehicle body use the same specification satellite positioning system, that is, both are Beidou positioning or both are GPS positioning systems.

[0047] The height beacon reflector storage unit is used to: pre-store the measured coordinates and measured height values of each group of height beacon reflectors, and perform co-location coordinate calibration with the lidar data processing unit in real time. For the points with the same coordinate position as the height beacon reflector, perform a subtraction operation on the height value of the height beacon reflector measured during the inspection by the lidar acquisition unit and the pre-stored measured height value to obtain a compensation value;

[0048] As an example, the compensation value can be a positive value or a negative value; that is, when the height value of the height beacon reflector measured during the inspection by the lidar acquisition unit is greater than the pre-stored measured height value corresponding to the height beacon reflector with the same coordinate, it is a positive value, and when the height value of the height beacon reflector measured during the inspection by the lidar acquisition unit is less than the pre-stored measured height value corresponding to the height beacon reflector with the same coordinate, it is a negative value.

[0049] As an example, the coordinate parameters and height values of each group of the height beacon reflectors can be recorded by an eight - bit or sixteen - bit binary code and stored in the storage unit of the height beacon reflector;

[0050] As an example, the number of the compensation values is multiple groups.

[0051] Step Two: The working process of the UAV flight platform control unit:

[0052] Control the UAV body to take off and inspect the overhead transmission line. Through the built - in lidar acquisition unit, three - dimensional data of the overhead transmission line and its surrounding environment are collected in real time, and the three - dimensional data are synchronously transmitted back to the lidar data processing unit;

[0053] Through the built - in thermal imaging determination unit, assist in determining whether there is a short - circuit or open - circuit in the wire, and feedback the determination result to the ground control unit in real time;

[0054] Control the UAV body to return and complete the recovery of the UAV body after the inspection;

[0055] Step Three: The working process of the lidar data processing unit:

[0056] The lidar data processing unit performs downsampling of the point cloud through the received three - dimensional data, and actually determines whether there is a measured scraping risk between each section of the wire sag and the obstacle;

[0057] That is, actually determine whether there is an intersection between the wire sag and the obstacle (such as a tree);

[0058] Because the overhead transmission line is relatively thin, when simply using the wire data collected by the lidar acquisition unit for downsampling of the point cloud operation and processing, there is easily a situation of wire data loss. Therefore, although using only the lidar acquisition unit for three - dimensional point cloud ranging data acquisition greatly reduces the operation data during high - definition image acquisition, reduces power consumption and equipment complexity, in the actual use process, there will be a situation of wire data loss, and thus it is impossible to accurately determine the scraping risk between the wire sag and the obstacle;

[0059] As an example, the lidar acquisition unit is: a laser rangefinder with a fan - shaped acquisition surface.

[0060] Step Four: The working process of the logic operation unit;

[0061] Calculate and output whether there is a scraping risk between each section of the wire sag and the environment. The calculation and determination rules include:

[0062] ① After introducing the compensation value through the parameters of the wire, calculate the theoretical sag values of each point of each section of the wire in real time;

[0063] As an example, the parameters of the wire include: wire material, ambient temperature, ambient humidity, and the height and span of the wire connecting to the power transmission tower at both ends, etc.

[0064] As an example, parameters such as the ambient temperature and humidity can be provided to the logic operation unit in real time by the induction device carried by the UAV body.

[0065] ② After ensuring the accuracy of the theoretical sag values of each point on each section of the wire by introducing the corresponding compensation values, the theoretical sag values of each point are integrated into the three-dimensional data corresponding to the collected and measured wire parameters that have been eliminated, and the point cloud thinning process is performed again to re-determine whether there is a theoretical collision risk between the sag of each section of the wire and the obstacles;

[0066] As an example, the theoretical sag values of each point can be determined by equidistant sampling or random sampling after presetting a fixed number of sampling values for each section of the wire.

[0067] ③ Perform a logical "AND" operation on the measured collision risk data value of each section with its corresponding theoretical collision risk data value to obtain whether there is a warning about the collision risk between the wire sag and the environment, that is:

[0068] When: both the measured collision risk data value and the theoretical collision risk data value are at risk, then the logic operation unit determines that there is a collision risk between the wire sag and the environment;

[0069] When: both the measured collision risk data value and the theoretical collision risk data value are risk-free, then the logic operation unit determines that there is no collision risk between the wire sag and the environment;

[0070] When: either the measured collision risk data value or the theoretical collision risk data value is at risk, then the logic operation unit determines that there is a collision risk between the wire sag and the environment;

[0071] As an example, the height beacon reflector only needs to be installed at the connection between the lowest wire between each power transmission tower and the insulator of the power transmission tower.

[0072] Considering that the wire sag can be calculated based on the ambient temperature, wire material, span distance between power transmission towers, and the angle between the wire and the horizontal plane, and its sag data value can be accurately obtained, the height beacon reflectors are respectively set at the insulators on the left and right sides of the lowest wire on two adjacent power transmission towers of a section of wire; the purpose of only setting on the lowest wire can save material costs and construction costs, because after the lowest wire sag touches an obstacle, it will naturally trigger an alarm. Whether the obstacle will touch the upper wire or not, it will be included in the alarm mechanism. Therefore, the lowest wire is the most sensitive point for alarm.

[0073] As an example, the height beacon reflector can also adopt an electronic transmitter with an active signal sending method, and use the electromagnetic field generated during the power transmission process of the wire or an external wind turbine power generation structure for green power supply.

[0074] As an example, in order to further reduce energy consumption, when the lidar data processing unit determines that there is a measured scraping risk between a certain section of the wire sag and an obstacle, the scraping risk calculation of the logic operation unit of this section of the wire is no longer performed.

[0075] Advantages of the present invention:

[0076] ① The mode of using three-dimensional high-definition shooting of real scene image information is filtered out, greatly reducing the amount of operations during data modeling, reducing the high-specification requirements for the chip, and also reducing power consumption and manufacturing costs.

[0077] ② Through the introduction of compensation values, a wire sag analysis mode combining two determinations is creatively designed, improving the determination accuracy of whether there is a scrape between the wire sag and an obstacle.

[0078] ③ For pure ranging data, its overall amount of operations is much lower than the image modeling operation amount of high-definition photography or the fusion operation amount of ranging and photography pictures, further reducing the heat generation of the chip and equipment, and extending the service life of the entire system. BRIEF DESCRIPTION OF THE DRAWINGS

[0079] Figure 1 is a schematic block diagram of the principle of the real-time detection system for overhead transmission line channels based on drones of the present invention.

[0080] Figure 2 is a schematic diagram of the installation effect of the height beacon reflector of the real-time detection system for overhead transmission line channels based on drones of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0081] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0082] Referring to Figures 1 to 2 as shown, a real-time detection system for overhead transmission line channels based on drones and its detection method, wherein:

[0083] The real-time detection system for overhead transmission line channels based on drones includes: a drone flight platform 101, a ground control unit 106, and multiple groups of height beacon reflectors 201;

[0084] The drone flight platform 101 includes: a drone body 102, and a lidar acquisition unit 103, an infrared thermal imaging measurement unit 104, and a position sensor 105 provided on the drone body 102;

[0085] As an example, the UAV body 102 adopts a UAV with vertical takeoff and landing by rotors and cruise by fixed wings;

[0086] As an example, the lidar acquisition unit 103 adopts a lidar rangefinder for real-time acquisition of data on wires, height beacon reflectors, and environmental parameters;

[0087] As an example, the thermal imaging measurement unit 104 is used to: assist in determining whether there is a short circuit or open circuit in the wire and to feedback the measurement result to the ground control unit in real time;

[0088] As an example, the position sensor 105 adopts: a high-precision position sensor; it is used to synchronize the position coordinates with the height beacon reflector 201.

[0089] The ground control unit 106 includes: a UAV flight platform control unit 107, a lidar data processing unit 108, a height beacon reflector storage unit 109, and a logic operation unit 110;

[0090] The UAV flight platform control unit 107 is used for: controlling the flight instructions of the UAV body 102, controlling the acquisition instructions of the lidar acquisition unit 103, controlling the measurement instructions of the thermal imaging measurement unit 104, and controlling the coordinate calibration instructions of the position sensor 105;

[0091] The lidar data processing unit 108 is used for: processing the data acquired by the lidar acquisition unit 103, and performing thinning point cloud processing on the three-dimensional data of the actual wires and the ground environment in real time, and actually determining whether there is a risk of actual scraping between each section of wire sag and obstacles;

[0092] The height beacon reflector storage unit 109 is used for: pre-storing the measured coordinates and measured height values of each group of height beacon reflectors 201, and performing the same position coordinate calibration with the lidar data processing unit 108 in real time, and performing a difference operation on the height value of the height beacon reflector 201 measured during the inspection by the lidar acquisition unit 103 and the pre-stored measured height value for the points with the same coordinate position as the height beacon reflector 201 to obtain a compensation value;

[0093] The logic operation unit 110 is used for: calculating and outputting whether there is a risk of scraping between each section of wire sag and the environment, and the calculation and determination rules include:

[0094] ① After passing the parameters of the wire and introducing the compensation value, the theoretical sag values of each point of each section of wire are calculated in real time;

[0095] As an example, the parameters of the wire include: wire material, ambient temperature, ambient humidity, and the height and span of the towers at both ends of the wire.

[0096] As an example, the introduced compensation value refers to the introduced compensation value of the height of the tower where both ends of the electric wire are connected.

[0097] As an example, the ambient temperature, humidity and other parameters can be provided to the logic operation unit in real time by the sensing device of the drone body.

[0098] ② After the accuracy of the theoretical sag value of each point of each section of the wire is guaranteed by introducing the compensation value, the theoretical sag value of each point is integrated into the corresponding three-dimensional data collected and the measured wire parameters are removed, and the point cloud is thinned again to determine whether there is a theoretical collision risk between the wire sag and the obstacle;

[0099] As an example, the theoretical sag value at each point can be determined by presetting a fixed number of values ​​for each section of the wire and then performing equidistant sampling or random sampling.

[0100] ③ Perform a logical “AND” operation on each of the measured scrape risk data values ​​and its corresponding theoretical scrape risk data value to obtain whether there is a wire sag and a scrape risk warning in the environment, that is:

[0101] When: the measured scratch risk data value and the theoretical scratch risk data value are both risky, the logic operation unit determines that there is a wire sag and environmental scratch risk;

[0102] When: the measured scratch risk data value and the theoretical scratch risk data value are both risk-free, the logic operation unit determines that there is no wire sag and environmental scratch risk;

[0103] When: either the measured scratch risk data value or the theoretical scratch risk data value is risky, the logic operation unit determines that there is a wire sag and environmental scratch risk;

[0104] The height beacon reflector 201 adopts a glass prism reflector. Since the glass prism reflector can easily reflect the laser ranging signal, it is easy to determine its own position information and height information. Each set of height beacon reflectors 201 is installed at each overlap between the electric wire and the insulating porcelain bottle of the tower.

[0105] As an example, the height beacon reflector 201 only needs to be installed at the joint between the lowest wire in each tower and the insulating porcelain bottle of the tower.

[0106] The detection method of the real-time detection system of overhead transmission line channel based on UAV includes:

[0107] Step 1, Parameter measurement and storage of each group of height beacon reflectors 201: Use a handheld high-precision position sensor combined with a laser rangefinder to collect the coordinate parameters and height values of each group of height beacon reflectors 201; and synchronously send them to the height beacon reflector storage unit 109; each group of height beacon reflectors 201 is installed at the lap joint of each wire and the insulator of the electric tower.

[0108] As an example, the handheld high-precision position sensor and the position sensor 105 on the UAV body 102 use the same specification satellite positioning system, that is, both are Beidou positioning or both are GPS positioning systems.

[0109] The height beacon reflector storage unit 109 is used for: pre-storing the measured coordinates and measured height values of each group of height beacon reflectors 201, and performing co-location coordinate calibration with the lidar data processing unit 108 in real time. For the points with the same coordinate position as the height beacon reflector 201, perform a difference operation on the height value measured during the inspection by the lidar acquisition unit 103 and the pre-stored measured height value to obtain a compensation value.

[0110] As an example, the compensation value can be a positive value or a negative value; that is, when the height value of the height beacon reflector 201 measured by the lidar acquisition unit 103 during the inspection is greater than the pre-stored measured height value corresponding to the height beacon reflector 201 with the same coordinate, it is a positive value, and when the height value of the height beacon reflector 201 measured by the lidar acquisition unit 103 during the inspection is less than the pre-stored measured height value corresponding to the height beacon reflector 201 with the same coordinate, it is a negative value.

[0111] As an example, the coordinate parameters and height values of each group of the height beacon reflectors 201 can be recorded by eight-bit or sixteen-bit binary codes and stored in the height beacon reflector storage unit 109.

[0112] Step 2, Working process of the UAV flight platform control unit 107:

[0113] Control the UAV body 102 to take off and inspect the overhead transmission line. Through the built-in lidar acquisition unit 103, collect the three-dimensional data of the overhead transmission line and its surrounding environment in real time, and synchronously transmit the three-dimensional data back to the lidar data processing unit 108.

[0114] Through the built-in thermal imaging measurement unit 104, assist in determining whether there is a short circuit or open circuit in the wire, and feedback the measurement result to the ground control unit 106 in real time.

[0115] Control the UAV body 102 to return and complete the recovery of the UAV body 102 after the inspection.

[0116] Step 3: Working process of the laser radar data processing unit 108:

[0117] The laser radar data processing unit 108 performs thinning point cloud processing on the received three-dimensional data to actually determine whether there is a measured scratch risk between each section of the wire sag and the obstacle;

[0118] That is, it is actually determined whether there is an intersection between the wire sag and obstacles (such as trees);

[0119] Because the overhead transmission lines are relatively thin, it is easy to lose frames of wire data when the wire data collected by the laser radar acquisition unit 103 is used alone for thinning point cloud computing processing. Therefore, the laser radar acquisition unit 103 is fully used to collect the ranging data of the three-dimensional point cloud. Although it greatly reduces the computing data during high-definition image collection, reduces power consumption and equipment complexity, there will be wire frame loss during actual use, and it is impossible to accurately determine the risk of wire sag and collision with obstacles;

[0120] As an example, the laser radar acquisition unit 103 is a laser rangefinder with a fan-shaped acquisition surface.

[0121] Step 4: Working process of the logic operation unit 110;

[0122] Calculate and output whether the wire sag has the risk of scratching the environment. The calculation and judgment rules include:

[0123] ① After the parameters of the wire are measured and the compensation value is introduced, the theoretical sag value of each point of each wire section is calculated in real time;

[0124] As an example, the parameters of the wire include: wire material, ambient temperature, ambient humidity, and the height of the tower at which both ends of the wire are connected.

[0125] As an example, the ambient temperature, humidity and other parameters can be provided to the logic operation unit in real time by the sensing device of the drone body.

[0126] ② After the accuracy of the theoretical sag value of each point of each section of the wire is guaranteed by introducing the compensation value, the theoretical sag value of each point is integrated into the corresponding three-dimensional data collected and the measured wire parameters are removed, and the point cloud is thinned again to determine whether there is a theoretical collision risk between the wire sag and the obstacle;

[0127] As an example, the theoretical sag value at each point can be determined by presetting a fixed number of values ​​for each section of the wire and then performing equidistant sampling or random sampling.

[0128] ③Perform a logical "AND" operation on each piece of the measured scraping risk data value and its corresponding theoretical scraping risk data value to obtain whether there is a warning of the scraping risk between the wire sag and the environment, that is:

[0129] When: both the measured scraping risk data value and the theoretical scraping risk data value are at risk, then the logical operation unit determines that there is a scraping risk between the wire sag and the environment;

[0130] When: both the measured scraping risk data value and the theoretical scraping risk data value are risk-free, then the logical operation unit determines that there is no scraping risk between the wire sag and the environment;

[0131] When: either the measured scraping risk data value or the theoretical scraping risk data value is at risk, then the logical operation unit determines that there is a scraping risk between the wire sag and the environment;

[0132] As an example, the height beacon reflector 201 only needs to be installed at the lap joint of the lowest wire between each two electric towers and the insulating porcelain bottle of the electric tower.

[0133] Considering that the wire sag can be calculated for the theoretical sag value based on parameters such as environmental temperature, wire material, span distance between electric towers, and height values at both ends of the wire, and its sag data value can be accurately obtained, the height beacon reflectors 201 are respectively set at the insulating porcelain bottles on the left and right sides of the lowest wire on two adjacent electric towers of a section of wire; the purpose of only setting on the lowest wire can save material costs and construction costs, because after the lowest wire sag touches an obstacle, it will naturally be alarmed. Whether the obstacle will touch the upper wire or not, it will be included in the alarm mechanism. Therefore, the lowest wire is the most sensitive value point for alarm;

[0134] As an example, the height beacon reflector 201 can also adopt an electronic transmitter with an active signal sending method, and use the electromagnetic field generated during the wire power transmission process or an external wind turbine power generation structure for green power supply.

[0135] The present invention filters out the mode of using three-dimensional high-definition shooting of real scene information, greatly reducing the amount of computation during data modeling, reducing the high-specification requirements for the chip, and also reducing power consumption and manufacturing costs; through the introduction of compensation values, a wire sag analysis mode combining two determinations is creatively designed, improving the determination accuracy of whether there is a scraping between the wire sag and obstacles; for pure ranging data, its overall amount of computation is much lower than the image modeling computation amount of high-definition photography or the fusion computation amount of ranging and photography images, further reducing the chip and device heating situation and extending the service life of the entire system.

[0136] The above are only the preferred embodiments of the present invention. It should be understood that the description of the above embodiments is only used to help understand the method and its core idea of the present invention, and is not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An unmanned aerial vehicle-based real-time detection system for overhead transmission line corridors, characterized in that, Including: An unmanned aerial vehicle (UAV) flight platform, a ground control unit, and multiple groups of height beacon reflectors; The UAV flight platform includes: a UAV body, and a lidar acquisition unit, a thermal imaging measurement unit, and a position sensor disposed on the UAV body; The lidar acquisition unit uses a lidar rangefinder to collect data on electric wires, height beacon reflectors, and environmental parameters in real time; The thermal imaging measurement unit is used to: assist in determining whether there is a short circuit or an open circuit in the electric wire, and feedback the measurement result to the ground control unit in real time; The position sensor uses: a high-precision position sensor; and is used for synchronizing with the position coordinates of the height beacon reflector; The ground control unit includes: a UAV flight platform control unit, a lidar data processing unit, a height beacon reflector storage unit, and a logic operation unit; The UAV flight platform control unit is used to: control the flight instructions of the UAV body, the acquisition instructions of the lidar acquisition unit, the measurement instructions of the thermal imaging measurement unit, and the coordinate calibration instructions of the position sensor; The lidar data processing unit is used to: process the data collected by the lidar acquisition unit, and perform thinning point cloud processing on the three-dimensional data of the actual electric wire and the ground environment in real time, and actually determine whether there is a measured scraping risk between each section of the electric wire sag and the obstacle; The height beacon reflector storage unit is used to: pre-store the measured coordinates and measured height values of each group of height beacon reflectors, and perform the same position coordinate calibration with the lidar data processing unit in real time. For the points with the same coordinate position as the height beacon reflector, perform a difference operation on the height value of the height beacon reflector measured during the lidar acquisition unit inspection and the pre-stored measured height value to obtain a compensation value; The logic operation unit is used to: calculate and output whether there is a scraping risk between each section of the electric wire sag and the environment. The calculation and determination rules include: ① Through the parameters of the electric wire, and after introducing the compensation value, calculate the theoretical sag values of each point of each section of the electric wire in real time; ② After ensuring the accuracy of the theoretical sag values of each point of each section of the electric wire by introducing the compensation value, integrate the theoretical sag values of each point into the corresponding collected three-dimensional data from which the measured electric wire parameters have been removed, and perform thinning point cloud processing again to secondarily determine whether there is a theoretical scraping risk between the electric wire sag and the obstacle; ③ Perform a logical "AND" operation on each section of the measured scraping risk data value and its corresponding theoretical scraping risk data value to obtain whether there is a warning of scraping risk between the electric wire sag and the environment, that is: When: both the measured scraping risk data value and the theoretical scraping risk data value are at risk, then the logic operation unit determines that there is a scraping risk between the electric wire sag and the environment; When: both the measured scraping risk data value and the theoretical scraping risk data value are risk-free, then the logic operation unit determines that there is no scraping risk between the electric wire sag and the environment; When: either the measured scraping risk data value or the theoretical scraping risk data value is at risk, then the logic operation unit determines that there is a scraping risk between the electric wire sag and the environment; The described height beacon reflector: uses a glass prism reflector. Since the glass prism reflector is easy to reflect the laser ranging signal, it is easy to determine its own position information and height information; each group of the height beacon reflectors is installed at the lap joint of each wire and the insulator of the electric tower.

2. The real-time detection system for overhead transmission line channels based on drones according to claim 1, characterized in that, The described UAV body uses: a UAV with the ability of vertical takeoff and landing by rotors and fixed-wing cruise.

3. The real-time detection system for overhead transmission line channels based on drones according to claim 1, wherein The parameters of the described wire include: wire material, ambient temperature, ambient humidity, and the height of the electric towers where the two ends of the wire are lapped.

4. The real-time detection system for overhead transmission line channels based on an unmanned aerial vehicle according to claim 3, wherein The parameters of the ambient temperature and humidity are provided to the described logic operation unit in real time by the induction device carried by the UAV body.

5. The real-time detection system for overhead transmission line channels based on an unmanned aerial vehicle according to claim 1, characterized in that, The theoretical sag values of each point are determined by equidistant sampling or random sampling after presetting a fixed number of values for each section of the wire.

6. The real-time detection system for overhead transmission line channels based on unmanned aerial vehicles according to claim 1, characterized in that, The described height beacon reflector only needs to be installed at the lap joint of the lowest wire and the insulator of the electric tower between each two electric towers.

7. Detection method of a real-time detection system for overhead transmission line channels based on unmanned aerial vehicles, characterized in that, Including: Step 1, parameter measurement and storage of each group of height beacon reflectors: Using a handheld high-precision position sensor combined with a laser rangefinder, collect the coordinate parameters and height values of each group of height beacon reflectors; and synchronously send them to the storage unit of the height beacon reflector; each group of the height beacon reflectors is installed at the lap joint of each wire and the insulator of the electric tower. The storage unit of the height beacon reflector is used for: pre-storing the measured coordinates and measured height values of each group of height beacon reflectors, and performing co-location coordinate calibration with the lidar data processing unit in real time. For the points with the same coordinate position as the height beacon reflector, perform a subtraction operation on the height value of the height beacon reflector measured during the inspection by the lidar acquisition unit and the pre-stored measured height value to obtain a compensation value. The compensation value is positive or negative. It is positive when the height value of the height beacon reflector measured during the inspection by the lidar acquisition unit is greater than the pre-stored measured height value corresponding to the height beacon reflector with the same coordinate, and it is negative when the height value of the height beacon reflector measured during the inspection by the lidar acquisition unit is less than the pre-stored measured height value corresponding to the height beacon reflector with the same coordinate. Step 2, working process of the UAV flight platform control unit: Control the UAV body to take off, inspect the overhead transmission line, and collect the three-dimensional data of the overhead transmission line and its surrounding environment in real time through the built-in lidar acquisition unit, and synchronously transmit the three-dimensional data back to the lidar data processing unit. Auxiliary determine whether there is a short circuit or open circuit in the wire through the built-in thermal imaging measurement unit, and feedback the measurement result to the ground control unit in real time. Control the UAV body to return and recover the UAV body after the inspection is completed. Step 3, working process of the lidar data processing unit: The lidar data processing unit performs downsampling of the point cloud through the received three-dimensional data, and actually determines whether there is a measured scraping risk between the sag of each section of the wire and the obstacle. Since the overhead transmission line is relatively thin, when simply using the wire data collected by the lidar acquisition unit and performing thinning point cloud operation processing, there is easily a situation of wire data frame loss. Therefore, although using only the lidar acquisition unit for three-dimensional point cloud ranging data acquisition greatly reduces the operation data during high-definition image acquisition and reduces power consumption and equipment complexity, in the actual use process, there will be wire frame loss, and thus it is impossible to accurately determine the risk of wire sag hitting obstacles; Step 4. The working process of the logic operation unit; Calculate and output whether there is a risk of each wire sag hitting the environment. The calculation and determination rules include: ① Through the parameters of the wire and introducing a compensation value, the theoretical sag values of each point of each section of the wire are calculated in real time; ② After introducing the compensation value to ensure the accuracy of the theoretical sag values of each point of each section of the wire, the theoretical sag values of each point are incorporated into the corresponding three-dimensional data that has been collected and the measured wire parameters have been removed, and thinning point cloud processing is performed again to secondarily determine whether there is a theoretical risk of the wire sag hitting an obstacle; ③ Perform a logical "AND" operation on the measured collision risk data value of each section and its corresponding theoretical collision risk data value to obtain whether there is a warning of the wire sag hitting the environment, that is: When: both the measured collision risk data value and the theoretical collision risk data value are at risk, then the logic operation unit determines that there is a risk of the wire sag hitting the environment; When: both the measured collision risk data value and the theoretical collision risk data value are risk-free, then the logic operation unit determines that there is no risk of the wire sag hitting the environment; When: either the measured collision risk data value or the theoretical collision risk data value is at risk, then the logic operation unit determines that there is a risk of the wire sag hitting the environment.

8. The detection method of the overhead transmission line corridor real-time detection system based on an unmanned aerial vehicle according to claim 7, characterized in that The handheld high-precision position sensor and the position sensor on the UAV body use the same specification satellite positioning system.

9. The detection method of the real-time detection system for overhead transmission line channels based on unmanned aerial vehicles according to claim 7, characterized in that, The coordinate parameters and height values of each group of the height beacon reflectors are recorded by eight-bit or sixteen-bit binary codes and stored in the height beacon reflector storage unit.

10. The detection method of the real-time detection system for overhead transmission line channels based on unmanned aerial vehicles according to claim 7, characterized in that, The lidar acquisition unit is: a laser rangefinder with a fan-shaped acquisition surface; the height beacon reflector is an electronic transmitter using an active signal transmission method, and uses the electromagnetic field generated during the wire power transmission process or an external wind turbine power generation structure for green power supply.

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