High-voltage line inspection method and system based on unmanned aerial vehicle

Abstract

The invention is suitable for the technical field of unmanned aerial vehicle inspection, and particularly relates to a high-voltage line inspection method and system based on an unmanned aerial vehicle, and the method comprises the steps: obtaining a high-voltage line map and high-voltage line setting parameters; a basic inspection path is generated, the unmanned aerial vehicle is controlled to conduct inspection based on the basic inspection path, and the unmanned aerial vehicle shifts towards the two sides in turn according to preset parameters in the inspection process; the horizontal position of the unmanned aerial vehicle is determined based on the laser ranging data, and correction processing is conducted; and constructing a two-dimensional model of each high-voltage line, determining the vertical flight height of the unmanned aerial vehicle, and checking the sag of the high-voltage lines. The unmanned aerial vehicle is provided with the laser range finder, the distance between the unmanned aerial vehicle and the high-voltage lines can be actively detected in the inspection process, the high-voltage lines are modeled according to the position relation between the unmanned aerial vehicle and the high-voltage lines, and therefore whether the high-voltage lines are abnormal or not is judged; and the position of the unmanned aerial vehicle can be corrected according to the position distribution of the high-voltage line, and the high-voltage line inspection efficiency is improved.

Description

Technical Field

[0001] This invention belongs to the field of unmanned aerial vehicle (UAV) inspection technology, and in particular relates to a method and system for inspecting high-voltage lines based on UAVs. Background Technology

[0002] High-voltage line inspection is a key measure to ensure the safe and stable operation of the power system. Through regular and special inspections, including ground patrols and pole climbing inspections, potential faults such as insulator damage, broken conductor strands, and loose hardware can be detected and addressed in a timely manner. Changes in line load, temperature, and other operating conditions can be monitored to prevent damage to the lines caused by external factors such as illegal construction, tree growth, and construction excavation. This ensures the reliability of power supply and reduces the occurrence of power outages.

[0003] With the development of drone technology, the inspection of high-voltage lines is gradually being completed by drones, which greatly improves the efficiency of the inspection. However, in the current drone inspection process, the drone mainly adopts the initial inspection by humans, and the drones carry out subsequent inspections according to the path of the initial inspection. However, this detection method cannot directly detect whether there are any abnormalities in the high-voltage lines, and can only be judged by humans, which is quite difficult to identify. Summary of the Invention

[0004] The purpose of this invention is to provide a high-voltage line inspection method based on drones, which aims to solve the problem that existing technologies cannot directly detect whether there are abnormalities in high-voltage lines and can only rely on manual judgment, which is difficult to identify.

[0005] This invention is implemented as follows: a high-voltage line inspection method based on unmanned aerial vehicles (UAVs), the method comprising:

[0006] The system acquires high-voltage line maps and high-voltage line setting parameters. The high-voltage line map records the location of the high-voltage lines, and the high-voltage line setting parameters record the distribution parameters of the high-voltage lines between any two adjacent towers, including the tower distance and the high-voltage line length. The drone is equipped with a laser rangefinder.

[0007] A basic inspection path is generated based on the high-voltage line map. The drone is then controlled to perform the inspection based on the basic inspection path. During the inspection, the drone deviates to both sides alternately according to preset parameters.

[0008] During the inspection process, laser ranging data is acquired, and the horizontal position of the drone is determined based on the laser ranging data, and correction processing is performed.

[0009] A two-dimensional model of each high-voltage line is constructed based on laser ranging data. The vertical flight altitude of the UAV is determined based on the two-dimensional model, and the sag of the high-voltage line is checked.

[0010] Preferably, the step of generating a basic inspection path based on the high-voltage line map, controlling the drone to perform inspections based on the basic inspection path, and having the drone alternately shift to both sides according to preset parameters during the inspection process specifically includes:

[0011] Identify the location of the towers in the high-voltage line map, and determine the location of the high-voltage lines between adjacent towers based on the location of the towers.

[0012] The positions of high-voltage lines between adjacent towers are sampled to obtain the coordinates of multiple inspection points, and a basic inspection path is generated based on the coordinates of the inspection points.

[0013] The drone is controlled to perform inspections based on the basic inspection path. When it is about to reach the inspection point, the drone is controlled to shift to both sides. The amount of shift is determined according to the high-voltage line setting parameters.

[0014] Preferably, the step of acquiring laser ranging data during the inspection process, determining the horizontal position of the UAV based on the laser ranging data, and performing correction processing specifically includes:

[0015] During the inspection process, laser ranging is continuously performed, and the ranging results are filtered to obtain laser ranging data, which includes the ranging value and the corresponding ranging time.

[0016] The time it takes for the drone to pass each high-voltage line and the distance to each high-voltage line are determined based on the ranging value and the corresponding ranging time.

[0017] Based on the time it takes for the drone to pass the outermost high-voltage line, control the drone to fly to the middle position between the high-voltage lines.

[0018] Preferably, the steps of constructing a two-dimensional model of each high-voltage line based on laser ranging data, determining the vertical flight altitude of the UAV based on the two-dimensional model, and verifying the sag of the high-voltage line specifically include:

[0019] Acquire the drone's positioning data, match the corresponding laser ranging data based on the positioning data, construct a two-dimensional coordinate system, and construct the high-voltage line ranging point in the two-dimensional coordinate system based on the laser ranging data;

[0020] Connect the high-voltage line ranging points to obtain a two-dimensional model, and perform function fitting based on the coordinates of the high-voltage line ranging points to construct the fitting function for the current high-voltage line;

[0021] The length and span of the high-voltage line are determined based on the high-voltage line setting parameters. A simulation function for the high-voltage line is generated, and the matching degree between the fitted function and the simulation function is calculated to determine whether there is any abnormal sag.

[0022] Preferably, the distance between the drone and each high-voltage line is determined based on laser ranging data, and the subsequent drone flight altitude is adjusted based on the distance between the drone and the high-voltage line.

[0023] Another object of the present invention is to provide a high-voltage line inspection system based on unmanned aerial vehicles (UAVs), the system comprising:

[0024] The parameter acquisition module is used to acquire high-voltage line maps and high-voltage line setting parameters. The high-voltage line map records the location of the high-voltage lines, and the high-voltage line setting parameters record the distribution parameters of the high-voltage lines between any two adjacent towers, including the tower distance and the high-voltage line length. The UAV is equipped with a laser rangefinder.

[0025] The inspection control module is used to generate a basic inspection path based on the high-voltage line map, and control the drone to carry out inspection based on the basic inspection path. During the inspection, the drone deviates to both sides alternately according to preset parameters.

[0026] The horizontal correction module is used to acquire laser ranging data during the inspection process, determine the horizontal position of the UAV based on the laser ranging data, and perform correction processing.

[0027] The cable inspection module is used to construct a two-dimensional model of each high-voltage line based on laser ranging data, determine the vertical flight altitude of the UAV based on the two-dimensional model, and check the sag of the high-voltage line.

[0028] Preferably, the inspection control module includes:

[0029] The high-voltage line positioning unit is used to identify the location of the towers in the high-voltage line map and determine the location of the high-voltage line between adjacent towers based on the location of the towers.

[0030] The path generation unit is used to sample the position of the high-voltage line between adjacent towers, obtain the coordinates of multiple inspection points, and generate a basic inspection path based on the coordinates of the inspection points.

[0031] The offset control unit is used to control the drone to perform inspections according to the basic inspection path. When it is about to reach the inspection point, it controls the drone to offset to both sides. The offset amount is determined according to the high-voltage line setting parameters.

[0032] Preferably, the horizontal correction module includes:

[0033] The laser ranging unit is used to continuously perform laser ranging during the inspection process, filter the ranging results, and obtain laser ranging data, which includes the ranging value and the corresponding ranging time.

[0034] The information calculation unit is used to determine the time it takes for the UAV to pass each high-voltage line and the distance to each high-voltage line based on the ranging value and the corresponding ranging time;

[0035] The position correction unit is used to control the drone to fly to the middle position between the high-voltage lines based on the time it takes for the drone to pass the outermost high-voltage line.

[0036] Preferably, the cable inspection module includes:

[0037] The ranging point construction unit is used to acquire the UAV's positioning data, match the corresponding laser ranging data based on the positioning data, construct a two-dimensional coordinate system, and construct the high-voltage line ranging point in the two-dimensional coordinate system based on the laser ranging data.

[0038] The function fitting unit is used to connect the high-voltage line ranging points to obtain a two-dimensional model, and to perform function fitting based on the coordinates of the high-voltage line ranging points to construct the fitting function of the current high-voltage line.

[0039] The function matching unit is used to determine the length and span of the high-voltage line based on the high-voltage line setting parameters, generate a simulation function of the high-voltage line, calculate the matching degree between the fitted function and the simulation function, and determine whether there is any sag anomaly.

[0040] Preferably, the distance between the drone and each high-voltage line is determined based on laser ranging data, and the subsequent drone flight altitude is adjusted based on the distance between the drone and the high-voltage line.

[0041] This invention provides a high-voltage line inspection method based on unmanned aerial vehicles (UAVs). By equipping the UAV with a laser rangefinder, the distance between the UAV and the high-voltage line can be actively detected during the inspection process. The high-voltage line can be modeled based on the positional relationship between the UAV and each high-voltage line, thereby determining whether there are any abnormalities in the high-voltage line. Furthermore, the position of the UAV can be corrected based on the positional distribution of the high-voltage line, thus improving the efficiency of high-voltage line inspection. Attached Figure Description

[0042] Figure 1 A flowchart illustrating a high-voltage line inspection method based on unmanned aerial vehicles (UAVs) provided in an embodiment of the present invention;

[0043] Figure 2 The flowchart illustrates the steps of generating a basic inspection path based on a high-voltage line map, controlling a drone to perform inspections based on the basic inspection path, and having the drone alternately shift to both sides according to preset parameters during the inspection process, as provided in this embodiment of the invention.

[0044] Figure 3 A flowchart illustrating the steps of acquiring laser ranging data during inspection, determining the horizontal position of a drone based on the laser ranging data, and performing deviation correction processing, as provided in an embodiment of the present invention.

[0045] Figure 4The flowchart illustrates the steps of constructing a two-dimensional model of each high-voltage line based on laser ranging data, determining the vertical flight altitude of the UAV based on the two-dimensional model, and verifying the sag of the high-voltage line, as provided in this embodiment of the invention.

[0046] Figure 5 An architecture diagram of a high-voltage line inspection system based on unmanned aerial vehicles (UAVs) is provided for an embodiment of the present invention.

[0047] Figure 6 An architecture diagram of an inspection control module provided in an embodiment of the present invention;

[0048] Figure 7 An architecture diagram of a horizontal correction module provided in an embodiment of the present invention;

[0049] Figure 8 This is an architecture diagram of a cable inspection module provided in an embodiment of the present invention. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0051] like Figure 1 The diagram shows a flowchart of a high-voltage line inspection method based on a drone provided in an embodiment of the present invention. The method includes:

[0052] S100 acquires high-voltage line maps and high-voltage line setting parameters. The high-voltage line map records the location of the high-voltage lines, and the high-voltage line setting parameters record the distribution parameters of the high-voltage lines between any two adjacent towers, including the tower distance and the length of the high-voltage lines. The drone is equipped with a laser rangefinder.

[0053] In this step, a high-voltage line map is obtained. The high-voltage line map records the location of each tower in the high-voltage line, including the tower coordinates and height. The high-voltage line setting parameters record the distance between any two adjacent towers and the length of the high-voltage cable between the two towers. For example, tower A and tower B are two adjacent towers. The altitude of tower A is 420 meters and the altitude of tower B is 450 meters. The straight-line distance between them is 1000 meters and the length of the high-voltage cable between them is 1200 meters. The drone is equipped with an image acquisition device to acquire images of the high-voltage line. The drone is also equipped with a laser rangefinder to continuously measure distances vertically downwards.

[0054] The S200 generates a basic inspection path based on the high-voltage line map, and controls the drone to carry out inspections based on the basic inspection path. During the inspection, the drone deviates to both sides alternately according to preset parameters.

[0055] In this step, a basic inspection path is generated based on the high-voltage line map. The projection of the high-voltage lines between towers onto the horizontal plane is a straight line. Sampling is performed along this straight line to determine multiple inspection points, such as setting an inspection point every 10 meters horizontally. Image acquisition is performed at the inspection points, and the coordinates of the inspection points are recorded. The inspection points are then connected to generate the basic inspection path. The drone then flies at a preset altitude according to the basic inspection path. Upon reaching an inspection point, image acquisition is performed using an image acquisition device. During this process, continuous distance measurement is performed using a laser rangefinder. Other types of distance measuring devices can also be used instead of a laser rangefinder. During the inspection process, to ensure the accuracy of sampling at the inspection points, the drone is controlled to shift to both sides of the high-voltage lines. At this time, the laser rangefinder on the drone will detect the high-voltage lines, thus determining the time it takes for the drone to pass each high-voltage line.

[0056] The S300 acquires laser ranging data during inspections, determines the drone's horizontal position based on the laser ranging data, and performs correction processing.

[0057] In this step, laser ranging data is acquired during the inspection process. The laser ranging data only includes the measurement data of the high-voltage line by the drone. Since the high-voltage line is at high altitude, the laser ranging data with a range value greater than the preset value is filtered out based on the ranging value. The laser ranging data records the time when the drone passes through each high-voltage line, thereby determining the position of the high-voltage line on both sides, and then controlling the drone to move to the center position between the two outer high-voltage lines so that the drone can pass through the inspection point.

[0058] The S400 constructs a two-dimensional model of each high-voltage line based on laser ranging data, determines the vertical flight altitude of the UAV based on the two-dimensional model, and verifies the sag of the high-voltage line.

[0059] In this step, a two-dimensional model of each high-voltage line is constructed based on laser ranging data. When the UAV flies between two sets of towers, it will pass the same high-voltage line multiple times, generating multiple sets of laser ranging data. The laser ranging data is distributed along the lines connecting the towers. By constructing a two-dimensional coordinate system, the laser ranging data belonging to the same high-voltage line are marked in the two-dimensional coordinate system, thus allowing the fitting function of the high-voltage line to be obtained. When the tower is installed, its high-voltage line setting parameters are already determined. The distribution of the cable between the towers can be determined based on the span, height difference, and high-voltage line length, in order to construct a simulation function of the high-voltage line. By comparing the simulation function and the fitting function, it can be determined whether there are any anomalies in the high-voltage line. When there are no anomalies in the high-voltage line, the position of the UAV between the two sets of towers can be determined based on the laser ranging data obtained from each measurement, thus realizing the position verification of the UAV.

[0060] like Figure 2 As shown, in a preferred embodiment of the present invention, the steps of generating a basic inspection path based on a high-voltage line map, controlling a drone to perform inspections based on the basic inspection path, and having the drone alternately shift to both sides according to preset parameters during the inspection process specifically include:

[0061] S201, Identify the location of the towers in the high-voltage line map, and determine the location of the high-voltage line between adjacent towers based on the location of the towers.

[0062] In this step, the location of the towers in the high-voltage line map is identified. The GPS coordinates of the towers are recorded in the high-voltage line map. The high-voltage line map is a planar map, that is, the coordinates in the height direction are discarded. After the location of the towers is determined, the horizontal distance between the towers can be obtained. The high-voltage lines between the towers are distributed between two groups of towers, and their projection on the horizontal plane is a parallel line.

[0063] S202, sample the positions of the high-voltage lines between adjacent towers to obtain the coordinates of multiple inspection points, and generate a basic inspection path based on the coordinates of the inspection points.

[0064] In this step, the location of the high-voltage line between adjacent towers is sampled. Specifically, in the high-voltage line map, two groups of towers are connected by a straight line, and sampling is carried out along this straight line. The sampling distance is a preset value, such as setting an inspection point every 20 meters. The inspection height is determined according to the height of the tower to obtain the coordinates of the inspection point. The coordinates of the inspection points are connected to obtain the basic inspection path between the two groups of towers. In the subsequent measurement process, the basic inspection path is adjusted.

[0065] S203 controls the drone to perform inspections based on the basic inspection path. When it is about to reach the inspection point, it controls the drone to shift to both sides. The amount of shift is determined according to the high-voltage line setting parameters.

[0066] In this step, the drone is controlled to inspect according to the basic inspection path. When the drone arrives at a tower, it will fly from one tower to the next along the basic inspection path. At the start of flight, it begins at a preset height from the tower; for example, if the tower's altitude is 300 meters, it will start at 303 meters. The drone's horizontal coordinates are determined by the basic inspection path. Between two inspection points, the drone adopts an S-shaped flight trajectory. The drone's flight speed is decomposed into three directions: the X-axis (parallel to the horizontal plane and parallel to the high-voltage line projection), the Y-axis (parallel to the horizontal plane and perpendicular to the X-axis), and the Z-axis (perpendicular to the horizontal plane, i.e., the altitude direction). The drone's velocity component in the X-axis direction remains constant. During inspection, the drone's starting position is first located to obtain the current high-voltage line spacing corresponding to the tower, i.e., the spacing L between two adjacent high-voltage lines. The drone is then controlled to move towards the Y-axis... The drone moves in the positive direction, maintaining a constant velocity component along the Y-axis. During flight, the laser rangefinder detects the corresponding high-voltage lines and records the last high-voltage line appearing in the positive Y-axis direction. It then flies in the opposite direction and records the last high-voltage line appearing in the negative Y-axis direction. The midpoint between these two positions is the drone's starting position. The drone begins its inspection from this position, moving along the X-axis. During inspection, as the drone reaches one inspection point and flies to the next, it is controlled to offset in both the positive and negative Y-axis directions. This allows the laser rangefinder to detect the position of the outermost high-voltage line. For example, if the leftmost high-voltage line is detected, the corresponding Y-axis coordinate is A; if the rightmost high-voltage line is detected, the corresponding Y-axis coordinate is C. The Y-axis coordinate of the sampling point is (A+C) / 2, thus determining the drone's real-time position and achieving accurate positioning along the Y-axis.

[0067] like Figure 3 As shown, in a preferred embodiment of the present invention, the steps of acquiring laser ranging data during the inspection process, determining the horizontal position of the UAV based on the laser ranging data, and performing correction processing specifically include:

[0068] S301 continuously performs laser ranging during the inspection process, filters the ranging results, and obtains laser ranging data, which includes the ranging value and the corresponding ranging time.

[0069] In this step, laser ranging is continuously performed during the inspection process. The ranging value is the smallest when passing high-voltage lines. High-voltage lines are screened according to the preset ranging range. For example, ranging results with a detection distance greater than 10 meters are screened out. The ranging value and corresponding ranging time of each set of laser ranging data are recorded.

[0070] S302 determines the time it takes for the drone to pass each high-voltage line and the distance between the drone and each high-voltage line based on the ranging value and the corresponding ranging time.

[0071] S303 controls the drone to fly to the middle position between the high-voltage lines based on the time it takes for the drone to pass the outermost high-voltage line.

[0072] In this step, the time it takes for the drone to pass each high-voltage line and the distance between each high-voltage line are determined based on the ranging value and the corresponding ranging time. Between two inspection points, the drone will shift to the left once, then to the right once, and finally return to the middle position and continue to fly in the X-axis direction, thus ensuring that the drone passes through the inspection point and acquires images through the image acquisition device when it arrives at the inspection point.

[0073] like Figure 4 As shown, in a preferred embodiment of the present invention, the steps of constructing a two-dimensional model of each high-voltage line based on laser ranging data, determining the vertical flight altitude of the UAV based on the two-dimensional model, and verifying the sag of the high-voltage line specifically include:

[0074] S401: Acquire the drone's positioning data, match the corresponding laser ranging data based on the positioning data, construct a two-dimensional coordinate system, and construct the high-voltage line ranging point in the two-dimensional coordinate system based on the laser ranging data.

[0075] In this step, the drone's positioning data is acquired. The corresponding positioning data is retrieved based on the time in the laser ranging data. For example, if a set of laser ranging data is acquired at time T0, the corresponding positioning data of the drone at that time is retrieved. Based on the positioning data and the corresponding laser ranging data, the distance between the drone and the high-voltage line at that location is determined. The point detected on the high-voltage line is the high-voltage line ranging point, and the coordinates of the high-voltage line ranging point are recorded.

[0076] S402 connects the high-voltage line ranging points to obtain a two-dimensional model, and performs function fitting based on the coordinates of the high-voltage line ranging points to construct the fitting function for the current high-voltage line.

[0077] In this step, the high-voltage line ranging points are connected. A two-dimensional coordinate system is constructed, and the positions of adjacent towers are marked in the two-dimensional coordinate system. Then, the coordinates of the high-voltage line ranging points (discarding the Y coordinate) are marked in the two-dimensional coordinate system. There will be multiple coordinate points in the two-dimensional coordinate system. The above coordinate points are fitted to obtain the fitting function corresponding to the high-voltage line.

[0078] S403: Determine the length and span of the high-voltage line based on the high-voltage line setting parameters, generate a simulation function for the high-voltage line, calculate the matching degree between the fitted function and the simulation function, and determine whether there is any abnormal sag.

[0079] In this step, the length and span of the high-voltage line are determined based on the high-voltage line setting parameters. The span between the towers and the length of the high-voltage line are known. Based on the relevant parameters of the high-voltage line, the high-voltage line as a whole belongs to the catenary model, thus constructing the corresponding catenary model. This catenary model can be represented by a function, i.e., a simulation function. Then, the matching degree between the simulation function and the fitting function is calculated. If the matching degree is greater than the preset value, it means that there is no abnormality in the sag of the current high-voltage line. Conversely, if the matching degree is not greater than the preset value, it means that there is an abnormality in sag. At this time, there may be a situation of tower tilting or cable stretching deformation, which requires maintenance.

[0080] The catenary model is represented as:

[0081]

[0082] Where a, c, and d are the parameters to be solved. Given the height of the tower, the span, and the length of the high-voltage line, the above parameters are solved to obtain the simulation function of the high-voltage line.

[0083] The degree of matching between the simulated function and the fitted function is obtained by calculating the mean square error. The mean squared deviation between the simulated function f(x) and the fitted function g(x) is calculated over n sampling points:

[0084]

[0085] If the MSE is greater than the preset value, an anomaly is determined.

[0086] During the drone's flight, since the high-voltage line is curved, in order to maintain the detection distance, after each detection, the distance between the drone and the high-voltage line is determined, and then the drone's flight altitude is adjusted, that is, the Z-axis coordinate of the drone's flight is changed, so that the distance between the drone and the high-voltage line is always within the preset range, thereby ensuring that the captured image is more stable and avoiding image changes caused by distance changes, which would affect the focus and recognition of the high-voltage line.

[0087] like Figure 5 As shown, an embodiment of the present invention provides a high-voltage line inspection system based on unmanned aerial vehicles (UAVs). The system includes:

[0088] The parameter acquisition module 100 is used to acquire high-voltage line maps and high-voltage line setting parameters. The high-voltage line map records the location of the high-voltage lines, and the high-voltage line setting parameters record the distribution parameters of the high-voltage lines between any two adjacent towers, including the tower distance and the high-voltage line length. The UAV is equipped with a laser rangefinder.

[0089] In this system, the parameter acquisition module 100 acquires a high-voltage line map, which records the location of each tower in the high-voltage line, including the tower coordinates and height. The high-voltage line setting parameters record the distance between any two adjacent towers and the length of the high-voltage cable between the two towers. For example, tower A and tower B are two adjacent towers. The altitude of tower A is 420 meters and the altitude of tower B is 450 meters. The straight-line distance between them is 1000 meters, and the length of the high-voltage cable between them is 1200 meters. The drone is equipped with an image acquisition device, which is used to acquire images of the high-voltage line. The drone is also equipped with a laser rangefinder, which is used for continuous vertical downward distance measurement.

[0090] The inspection control module 200 is used to generate a basic inspection path based on the high-voltage line map, and control the drone to carry out inspection based on the basic inspection path. During the inspection, the drone deviates to both sides alternately according to preset parameters.

[0091] In this system, the inspection control module 200 generates a basic inspection path based on the high-voltage line map. The projection of the high-voltage lines between towers onto the horizontal plane is a straight line. Sampling is performed on this straight line to determine multiple inspection points, such as setting an inspection point every 10 meters horizontally. Image acquisition is performed at the inspection points, the coordinates of the inspection points are recorded, and the inspection points are connected to generate the basic inspection path. The UAV then flies at a preset altitude according to the basic inspection path. When it arrives at an inspection point, it acquires images through an image acquisition device. During this process, continuous ranging is performed using a laser rangefinder. Other types of ranging devices can also be used instead of laser rangefinders. During the inspection process, in order to ensure the sampling accuracy of the inspection points, the UAV is controlled to shift to both sides of the high-voltage lines. At this time, the laser rangefinder on the UAV will detect the high-voltage lines, thereby determining the time it takes for the UAV to pass each high-voltage line.

[0092] The horizontal correction module 300 is used to acquire laser ranging data during the inspection process, determine the horizontal position of the UAV based on the laser ranging data, and perform correction processing.

[0093] In this system, the horizontal correction module 300 acquires laser ranging data during the inspection process. The laser ranging data only includes the measurement data of the UAV to the high-voltage line. Since the high-voltage line is at high altitude, the laser ranging data with a range value greater than the preset value is filtered out based on the ranging value. The laser ranging data records the time when the UAV passes through each high-voltage line, thereby determining the position of the high-voltage line on both sides, and then controlling the UAV to move to the center position between the two outer high-voltage lines, so that the UAV can pass through the inspection point.

[0094] The cable inspection module 400 is used to construct a two-dimensional model of each high-voltage line based on laser ranging data, determine the vertical flight altitude of the UAV based on the two-dimensional model, and check the sag of the high-voltage line.

[0095] In this system, the cable inspection module 400 constructs a two-dimensional model of each high-voltage line based on laser ranging data. When the UAV flies between two sets of towers, it will pass the same high-voltage line multiple times, generating multiple sets of laser ranging data. The laser ranging data is distributed along the line connecting the towers. By constructing a two-dimensional coordinate system, the laser ranging data belonging to the same high-voltage line are marked in the two-dimensional coordinate system, thereby fitting the fitting function of the high-voltage line. When the tower is installed, its high-voltage line setting parameters are already determined. The distribution of the cable between the towers can be determined based on the span, height difference, and high-voltage line length, so as to construct a simulation function of the high-voltage line. By comparing the simulation function and the fitting function, it can be determined whether there is any abnormality in the high-voltage line. When there is no abnormality in the high-voltage line, the position of the UAV between the two sets of towers can be determined based on the laser ranging data obtained from each measurement, thereby realizing the position verification of the UAV.

[0096] like Figure 6 As shown, in a preferred embodiment of the present invention, the inspection control module 200 includes:

[0097] The high-voltage line positioning unit 201 is used to identify the location of the towers in the high-voltage line map and determine the location of the high-voltage line between adjacent towers based on the location of the towers.

[0098] In this module, the high-voltage line positioning unit 201 identifies the location of the towers in the high-voltage line map. The GPS coordinates of the towers are recorded in the high-voltage line map. The high-voltage line map is a planar map, that is, the coordinates in the height direction are discarded. After the location of the towers is determined, the horizontal distance between the towers can be obtained. The high-voltage lines between the towers are distributed between two groups of towers, and their projection on the horizontal plane is a parallel line.

[0099] The path generation unit 202 is used to sample the position of the high-voltage line between adjacent towers, obtain the coordinates of multiple inspection points, and generate a basic inspection path based on the coordinates of the inspection points.

[0100] In this module, the path generation unit 202 samples the location of the high-voltage line between adjacent towers. Specifically, in the high-voltage line map, two groups of towers are connected by a straight line, and sampling is performed on this straight line. The sampling distance is a preset value, such as setting an inspection point every 20 meters. The inspection height is determined according to the height of the tower to obtain the coordinates of the inspection point. The coordinates of the inspection points are connected to obtain the basic inspection path between the two groups of towers. In the subsequent measurement process, the basic inspection path is adjusted.

[0101] The offset control unit 203 is used to control the drone to perform inspections according to the basic inspection path. When it is about to reach the inspection point, it controls the drone to offset to both sides. The offset amount is determined according to the high-voltage line setting parameters.

[0102] In this module, the offset control unit 203 controls the UAV inspection according to the basic inspection path. When the UAV arrives at a tower, it will fly from one tower to the next along the basic inspection path. At the start of flight, it begins at a preset height from the tower; for example, if the tower's altitude is 300 meters, it can start at 303 meters. The UAV's horizontal coordinates are determined by the basic inspection path. Between two inspection points, the UAV adopts an S-shaped flight trajectory. The UAV's flight speed is decomposed into three directions: the X-axis (parallel to the horizontal plane and parallel to the high-voltage line projection), the Y-axis (parallel to the horizontal plane and perpendicular to the X-axis), and the Z-axis (perpendicular to the horizontal plane, i.e., the altitude direction). The UAV's velocity component in the X-axis direction remains constant. During inspection, the starting position of the UAV is first located to obtain the current high-voltage line spacing corresponding to the tower, i.e., the spacing L between two adjacent high-voltage lines. The UAV is then controlled accordingly. The drone moves in the positive Y-axis direction, maintaining a constant velocity component along the Y-axis. During flight, the laser rangefinder detects the corresponding high-voltage lines and records the last high-voltage line appearing in the positive Y-axis direction. It then flies in the opposite direction and records the last high-voltage line appearing in the negative Y-axis direction. The midpoint between these two positions is the drone's starting position. From this position, the drone begins its inspection and moves along the X-axis. During inspection, as the drone reaches one inspection point and flies to the next, it is controlled to offset in both the positive and negative Y-axis directions. This allows the laser rangefinder to detect the position of the outermost high-voltage line. For example, if the leftmost high-voltage line is detected, the corresponding Y-axis coordinate is A; if the rightmost high-voltage line is detected, the corresponding Y-axis coordinate is C. Therefore, the Y-axis coordinate of the sampling point is (A+C) / 2, thus determining the drone's real-time position and achieving accurate positioning along the Y-axis.

[0103] like Figure 7 As shown, in a preferred embodiment of the present invention, the horizontal correction module 300 includes:

[0104] The laser ranging unit 301 is used to continuously perform laser ranging during the inspection process, filter the ranging results, and obtain laser ranging data, which includes the ranging value and the corresponding ranging time.

[0105] In this module, the laser ranging unit 301 continuously performs laser ranging during the inspection process. When passing high-voltage lines, the ranging value obtained is the smallest. The high-voltage lines are screened according to the preset ranging range. For example, ranging results with a detection distance greater than 10 meters are screened out. The ranging value and corresponding ranging time of each set of laser ranging data are recorded.

[0106] The information calculation unit 302 is used to determine the time it takes for the UAV to pass through each high-voltage line and the distance between the UAV and each high-voltage line based on the ranging value and the corresponding ranging time.

[0107] The position correction unit 303 is used to control the drone to fly to the middle position between the high-voltage lines based on the time it takes for the drone to pass the outermost high-voltage line.

[0108] In this module, the time it takes for the drone to pass each high-voltage line and the distance between the drone and each high-voltage line are determined based on the ranging value and the corresponding ranging time. Between two inspection points, the drone will shift to the left once, then to the right once, and finally return to the middle position and continue to fly in the X-axis direction, thus ensuring that the drone passes through the inspection point and acquires images through the image acquisition device when it arrives at the inspection point.

[0109] like Figure 8 As shown, in a preferred embodiment of the present invention, the cable inspection module 400 includes:

[0110] The ranging point construction unit 401 is used to acquire the positioning data of the UAV, match the corresponding laser ranging data according to the positioning data, construct a two-dimensional coordinate system, and construct the high-voltage line ranging point in the two-dimensional coordinate system according to the laser ranging data.

[0111] In this module, the ranging point construction unit 401 acquires the UAV's positioning data and retrieves the corresponding positioning data based on the time in the laser ranging data. For example, if a set of laser ranging data is acquired at time T0, the corresponding UAV's positioning data at that time is retrieved. Based on the positioning data and the corresponding laser ranging data, the distance between the UAV and the high-voltage line at that location is determined. The point detected on the high-voltage line is the high-voltage line ranging point, and the coordinates of the high-voltage line ranging point are recorded.

[0112] The function fitting unit 402 is used to connect the high-voltage line ranging points to obtain a two-dimensional model, and to perform function fitting based on the coordinates of the high-voltage line ranging points to construct the fitting function of the current high-voltage line.

[0113] In this module, the function fitting unit 402 connects the high-voltage line ranging points, constructs a two-dimensional coordinate system, marks the positions of adjacent towers in the two-dimensional coordinate system, and then marks the coordinates of the high-voltage line ranging points (discarding the Y coordinate) in the two-dimensional coordinate system. There will be multiple coordinate points in the two-dimensional coordinate system. The fitting function corresponding to the high-voltage line is obtained by fitting the above coordinate points.

[0114] The function matching unit 403 is used to determine the length and span of the high-voltage line according to the high-voltage line setting parameters, generate a simulation function of the high-voltage line, calculate the matching degree between the fitted function and the simulation function, and determine whether there is an abnormal sag.

[0115] In this module, the function matching unit 403 determines the length and span of the high-voltage line based on the high-voltage line setting parameters. The span between the towers and the length of the high-voltage line are known. Based on the relevant parameters of the high-voltage line, the high-voltage line as a whole belongs to the catenary model, thus constructing the corresponding catenary model. This catenary model can be represented by a function, i.e., a simulation function. Then, the matching degree between the simulation function and the fitting function is calculated. If the matching degree is greater than the preset value, it means that there is no abnormality in the sag of the current high-voltage line. Conversely, if the matching degree is not greater than the preset value, it means that there is an abnormality in the sag. At this time, there may be a situation of tower tilting or cable stretching deformation, which requires maintenance.

[0116] The catenary model is represented as:

[0117]

[0118] Where a, c, and d are the parameters to be solved. Given the height of the tower, the span, and the length of the high-voltage line, the above parameters are solved to obtain the simulation function of the high-voltage line.

[0119] The degree of matching between the simulated function and the fitted function is obtained by calculating the mean square error. The mean squared deviation between the simulated function f(x) and the fitted function g(x) is calculated over n sampling points:

[0120]

[0121] If the MSE is greater than the preset value, an anomaly is determined.

[0122] During the drone's flight, since the high-voltage line is curved, in order to maintain the detection distance, after each detection, the distance between the drone and the high-voltage line is determined, and then the drone's flight altitude is adjusted, that is, the Z-axis coordinate of the drone's flight is changed, so that the distance between the drone and the high-voltage line is always within the preset range, thereby ensuring that the captured image is more stable and avoiding image changes caused by distance changes, which would affect the focus and recognition of the high-voltage line.

[0123] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for inspecting high-voltage lines based on unmanned aerial vehicles (UAVs), characterized in that, The method includes: The system acquires high-voltage line maps and high-voltage line setting parameters. The high-voltage line map records the location of the high-voltage lines, and the high-voltage line setting parameters record the distribution parameters of the high-voltage lines between any two adjacent towers, including the tower distance and the high-voltage line length. The drone is equipped with a laser rangefinder. A basic inspection path is generated based on the high-voltage line map. The drone is then controlled to perform the inspection based on the basic inspection path. During the inspection, the drone deviates to both sides alternately according to preset parameters. During the inspection process, laser ranging data is acquired, and the horizontal position of the drone is determined based on the laser ranging data, and correction processing is performed. A two-dimensional model of each high-voltage line is constructed based on laser ranging data. The vertical flight altitude of the UAV is determined based on the two-dimensional model, and the sag of the high-voltage line is checked.

2. The high-voltage line inspection method based on unmanned aerial vehicles (UAVs) according to claim 1, characterized in that, The steps of generating a basic inspection path based on the high-voltage line map, controlling the drone to perform inspections based on the basic inspection path, and having the drone alternately shift to both sides according to preset parameters during the inspection process specifically include: Identify the location of the towers in the high-voltage line map, and determine the location of the high-voltage lines between adjacent towers based on the location of the towers. The positions of high-voltage lines between adjacent towers are sampled to obtain the coordinates of multiple inspection points, and a basic inspection path is generated based on the coordinates of the inspection points. The drone is controlled to perform inspections based on the basic inspection path. When it is about to reach the inspection point, the drone is controlled to shift to both sides. The amount of shift is determined according to the high-voltage line setting parameters.

3. The high-voltage line inspection method based on unmanned aerial vehicles (UAVs) according to claim 1, characterized in that, The steps of acquiring laser ranging data during the inspection process, determining the horizontal position of the UAV based on the laser ranging data, and performing correction processing specifically include: During the inspection process, laser ranging is continuously performed, and the ranging results are filtered to obtain laser ranging data, which includes the ranging value and the corresponding ranging time. The time it takes for the drone to pass each high-voltage line and the distance to each high-voltage line are determined based on the ranging value and the corresponding ranging time. Based on the time it takes for the drone to pass the outermost high-voltage line, control the drone to fly to the middle position between the high-voltage lines.

4. The high-voltage line inspection method based on unmanned aerial vehicles (UAVs) according to claim 1, characterized in that, The steps of constructing a two-dimensional model of each high-voltage line based on laser ranging data, determining the vertical flight altitude of the UAV based on the two-dimensional model, and verifying the sag of the high-voltage line specifically include: Acquire the drone's positioning data, match the corresponding laser ranging data based on the positioning data, construct a two-dimensional coordinate system, and construct the high-voltage line ranging point in the two-dimensional coordinate system based on the laser ranging data; Connect the high-voltage line ranging points to obtain a two-dimensional model, and perform function fitting based on the coordinates of the high-voltage line ranging points to construct the fitting function for the current high-voltage line; The length and span of the high-voltage line are determined based on the high-voltage line setting parameters. A simulation function for the high-voltage line is generated, and the matching degree between the fitted function and the simulation function is calculated to determine whether there is any abnormal sag.

5. The high-voltage line inspection method based on unmanned aerial vehicles (UAVs) according to claim 4, characterized in that, The distance between the drone and each high-voltage line is determined based on laser ranging data, and the drone's subsequent flight altitude is adjusted accordingly.

6. A high-voltage line inspection system based on unmanned aerial vehicles (UAVs), characterized in that, The system includes: The parameter acquisition module is used to acquire high-voltage line maps and high-voltage line setting parameters. The high-voltage line map records the location of the high-voltage lines, and the high-voltage line setting parameters record the distribution parameters of the high-voltage lines between any two adjacent towers, including the tower distance and the high-voltage line length. The UAV is equipped with a laser rangefinder. The inspection control module is used to generate a basic inspection path based on the high-voltage line map, and control the drone to carry out inspection based on the basic inspection path. During the inspection, the drone deviates to both sides alternately according to preset parameters. The horizontal correction module is used to acquire laser ranging data during the inspection process, determine the horizontal position of the UAV based on the laser ranging data, and perform correction processing. The cable inspection module is used to construct a two-dimensional model of each high-voltage line based on laser ranging data, determine the vertical flight altitude of the UAV based on the two-dimensional model, and check the sag of the high-voltage line.

7. The high-voltage line inspection system based on unmanned aerial vehicles (UAVs) according to claim 6, characterized in that, The inspection control module includes: The high-voltage line positioning unit is used to identify the location of the towers in the high-voltage line map and determine the location of the high-voltage line between adjacent towers based on the location of the towers. The path generation unit is used to sample the position of the high-voltage line between adjacent towers, obtain the coordinates of multiple inspection points, and generate a basic inspection path based on the coordinates of the inspection points. The offset control unit is used to control the drone to perform inspections according to the basic inspection path. When it is about to reach the inspection point, it controls the drone to offset to both sides. The offset amount is determined according to the high-voltage line setting parameters.

8. The high-voltage line inspection system based on unmanned aerial vehicles (UAVs) according to claim 6, characterized in that, The horizontal correction module includes: The laser ranging unit is used to continuously perform laser ranging during the inspection process, filter the ranging results, and obtain laser ranging data, which includes the ranging value and the corresponding ranging time. The information calculation unit is used to determine the time it takes for the UAV to pass each high-voltage line and the distance to each high-voltage line based on the ranging value and the corresponding ranging time; The position correction unit is used to control the drone to fly to the middle position between the high-voltage lines based on the time it takes for the drone to pass the outermost high-voltage line.

9. The high-voltage line inspection system based on unmanned aerial vehicles (UAVs) according to claim 6, characterized in that, The cable inspection module includes: The ranging point construction unit is used to acquire the UAV's positioning data, match the corresponding laser ranging data based on the positioning data, construct a two-dimensional coordinate system, and construct the high-voltage line ranging point in the two-dimensional coordinate system based on the laser ranging data. The function fitting unit is used to connect the high-voltage line ranging points to obtain a two-dimensional model, and to perform function fitting based on the coordinates of the high-voltage line ranging points to construct the fitting function of the current high-voltage line. The function matching unit is used to determine the length and span of the high-voltage line based on the high-voltage line setting parameters, generate a simulation function of the high-voltage line, calculate the matching degree between the fitted function and the simulation function, and determine whether there is any sag anomaly.

10. The high-voltage line inspection system based on unmanned aerial vehicles (UAVs) according to claim 9, characterized in that, The distance between the drone and each high-voltage line is determined based on laser ranging data, and the drone's subsequent flight altitude is adjusted accordingly.

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