Single-beidou RTK high-precision positioning method for power transmission line working condition monitoring

Abstract

The application discloses a single Beidou RTK high-precision positioning method for power transmission line working condition monitoring, and relates to the technical field of unmanned aerial vehicle positioning, solves the problem that an unmanned aerial vehicle is prone to electromagnetic interference in the positioning process, and causes low precision, the application accurately determines the position characteristics of a reference station associated satellite, such as locking the associated time when the satellite signal strength is the highest, accurately calculates the characteristic distance by using the signal strength parameter, and then determines the position of the associated satellite, thereby providing a high-precision reference basis for subsequent unmanned aerial vehicle positioning. In the unmanned aerial vehicle positioning process, the characteristic time difference of the unmanned aerial vehicle, the reference station and the associated satellite signal is comprehensively utilized to calculate the distance, and the position points are accurately screened through the spatial position relationship, so that the positioning accuracy is greatly improved, and the strict requirement of the power transmission line working condition monitoring on the centimeter-level or even higher precision positioning can be met.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of unmanned aerial vehicle positioning, in particular to a single Beidou RTK high-precision positioning method for power transmission line working condition monitoring. BACKGROUND

[0002] With the continuous growth of the demand for electricity in modern society, the safe and stable operation of the power transmission line, as the key channel for power transmission, is of great importance; the power transmission line often crosses complex and diverse geographical environments, including high mountains, valleys, forests and densely populated areas, etc., which makes the line face many potential safety hazards such as tower inclination, line icing and external damage. In order to timely discover and deal with these potential risks and ensure reliable power supply, efficient and accurate working condition monitoring of the power transmission line becomes an inevitable requirement.

[0003] Among the existing power transmission line working condition monitoring methods, the traditional positioning technology has many limitations in terms of accuracy and reliability; for example, the conventional GPS positioning is greatly affected by factors such as satellite signal coverage, building obstruction and signal interference, and it is difficult to achieve high-precision positioning in complex geographical environments, which greatly reduces the accuracy of the monitoring data and cannot provide accurate line condition information for the operation and maintenance personnel. Although some positioning systems based on ground stations can improve the positioning effect to some extent, they have limited coverage, high construction and maintenance costs and other problems, which cannot meet the needs of long-distance and large-scale power transmission line monitoring.

[0004] At the same time, with the gradual application of unmanned aerial vehicle technology in the power industry, it has become a trend to use unmanned aerial vehicles to carry monitoring equipment for the inspection of power transmission lines; however, to fully utilize the advantages of unmanned aerial vehicle inspection and achieve fine monitoring of power transmission lines, the problem of high-precision positioning of unmanned aerial vehicles during flight must be solved. Only by accurately knowing the position of the unmanned aerial vehicle can it be ensured to fly accurately according to the preset route, conduct comprehensive and detailed inspection of the power transmission line facilities, and accurately record the position information of each monitoring point, providing a reliable basis for subsequent data analysis and fault diagnosis.

[0005] Under this background, the single Beidou RTK high-precision positioning method emerges as the times require; the Beidou satellite navigation system, as a satellite navigation system independently developed by China, has the advantages of wide signal coverage and strong anti-interference capability. Combined with the RTK (Real-Time Kinematic) technology, by setting up a reference station in the power transmission line and using an unmanned aerial vehicle equipped with a Beidou RTK receiver as a mobile station, real-time differential positioning is realized, which is expected to break through the bottleneck of traditional positioning technology and provide a high-precision and high-reliability positioning solution for power transmission line working condition monitoring, thereby promoting the upgrading and development of power transmission line monitoring technology. SUMMARY

[0006] In view of the deficiencies of the prior art, the single Beidou RTK high-precision positioning method for power line working condition monitoring is provided, which solves the problem that the unmanned aerial vehicle is easily affected by electromagnetic interference in the positioning process, resulting in low precision.

[0007] To achieve the above object, the following technical solutions are adopted: the single Beidou RTK high-precision positioning method for power line working condition monitoring comprises the following steps:

[0008] Step one, the position of the reference station calibrated in the power line is determined, and based on the satellite signals received by the reference station, the associated time of the satellite signal with the highest strength is confirmed, and based on the confirmed associated time, the position characteristics of the associated satellite are confirmed, and the specific method is:

[0009] When the satellite signal of the associated satellite is received from the reference station, the different satellite signals associated in the subsequent different time are received and confirmed;

[0010] Confirm the strength of the received satellite signal: sort the satellite signals confirmed at different times, and sequentially confirm the amplitude of the sorted satellite signals, lock the first group of peak points and the first group of valley points of the corresponding satellite signal, the peak point is the highest amplitude point, and the valley point is the lowest amplitude point, the amplitude associated with the first group of peak points is recorded as F1, and the amplitude associated with the first group of valley points is recorded as F2, and the strength parameter FQ associated with the corresponding satellite signal is confirmed by using: FQ=(F1-F2);

[0011] According to the gradually sorted satellite signals, the associated strength parameter FQ is sorted, and from the sorted strength parameter sequence, the characteristic value is selected, and the strength parameters adjacent to the characteristic value are smaller than the value, and the time corresponding to the characteristic value is recorded as the associated time;

[0012] Record the satellite signal associated with the associated time as the undetermined signal, confirm the sending time from the undetermined signal, confirm the interval time t between the sending time and the associated time, and lock the characteristic distance by using: Vxt=JL, wherein V is a preset value;

[0013] Based on the position of the reference station and the preset signal receiving direction, a group of vectors are constructed with the position of the reference station as the initial point, the length of the vector is the characteristic distance, the vector points in the same direction as the signal receiving direction, and based on the preset surrounding angle, the vector rotates around the initial point, and the spherical region confirmed in the rotation process is taken as the position characteristics of the associated satellite.

[0014] Step two, dispatch the unmanned aerial vehicle with RTK, and control the unmanned aerial vehicle to receive the signals sent by the associated satellite and the reference station during the flight of the unmanned aerial vehicle, and based on the signal characteristics of the received signals, the position of the unmanned aerial vehicle is preliminarily positioned, and the specific method is:

[0015] The signal received by the unmanned aerial vehicle at the corresponding time belongs to the reference station, and the signal received by the unmanned aerial vehicle at the corresponding time belongs to the associated satellite;

[0016] Confirm the feature time difference associated with the ground signal at the corresponding time, lock the sending time of the ground signal and mark it as T1, and then mark the corresponding time as T2, confirm the feature time difference by: Feature time difference = |T1-T2|, and confirm the ground distance between the unmanned aerial vehicle and the reference station by: Feature time difference x V = ground distance, V is a preset value;

[0017] Confirm the feature time difference associated with the corresponding time air signal, lock the sending time of the air signal and the corresponding time, confirm the corresponding feature time difference, and then lock the air distance between the unmanned aerial vehicle and the associated satellite in combination with the preset speed V;

[0018] Based on the confirmed ground distance and the position of the reference station, take the position of the reference station as the center of the circle, and take the ground distance as the radius to confirm a group of spherical regions;

[0019] Based on the position characteristics confirmed by the associated satellite, randomly lock the feature points from the position characteristics, and confirm the straight line distance between the feature points and any point in the spherical region. The point with the same straight line distance as the air distance is marked as the positioning point, and the confirmed positioning points in the spherical region are marked in the spherical region. Different positioning points associated with different feature points are different, so there are multiple positioning points in the spherical region.

[0020] Step three, based on the positioning data associated in the preliminary positioning process of the unmanned aerial vehicle, confirm the positioning data associated at the next time, and based on the data characteristics of the positioning data between adjacent time and the flight direction of the unmanned aerial vehicle, complete the high-precision positioning process of the unmanned aerial vehicle, and bundle the real-time positioning data with the monitoring data to generate a bundled data package for display. The specific method is:

[0021] The positioning data confirmed at the last group of time is used as the initial data, and the positioning data includes spherical regions and marked positioning points.

[0022] The same processing method as step two is used to confirm the positioning data associated at the current time as verification data.

[0023] Mark several positioning points in the initial data as initial points, mark several positioning points in the verification data as verification points, mark the flight direction of the unmanned aerial vehicle as a reference direction, select the initial points in turn, and move the initial points according to the reference direction according to the confirmed reference direction, and determine whether there is a verification point completely coinciding with the initial point in the moving process, if there is, mark the initial point and the verification point as high-precision positioning points, if not, continue to confirm until the high-precision positioning points are confirmed;

[0024] When positioning subsequently, start from the high-precision positioning points determined at the previous moment, and lock the high-precision positioning points from the positioning points confirmed at the next moment according to the reference direction, complete the high-precision positioning process, and based on the high-precision positioning process performed in real time, bundle the working condition data and positioning data monitored by the unmanned aerial vehicle, and display the bundled data packet.

[0025] The application provides a single Beidou RTK high-precision positioning method for power line working condition monitoring.

[0026] The application accurately determines the position characteristics of the associated satellite of the reference station, such as locking the associated moment with the highest satellite signal strength, accurately calculates the characteristic distance using the signal strength parameter, and then determines the position of the associated satellite, thereby providing a high-precision reference basis for subsequent unmanned aerial vehicle positioning. In the unmanned aerial vehicle positioning process, the characteristic time difference of the signals of the unmanned aerial vehicle, the reference station and the associated satellite is comprehensively utilized to calculate the distance, and the positioning points are accurately screened through the spatial position relationship, thereby greatly improving the accuracy of positioning and meeting the strict requirements of power line working condition monitoring on centimeter-level or even higher precision positioning.

[0027] From the analysis and processing of satellite signals by the reference station to the real-time reception and positioning calculation of signals during the flight of the unmanned aerial vehicle, to the comparison of positioning data at adjacent moments and the rapid determination of high-precision positioning points, the entire process is coherent and efficient. Without too much manual intervention, a large amount of positioning data processing and analysis can be completed in a short time, greatly shortening the monitoring period and improving the working efficiency of power line working condition monitoring. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The figure is a schematic diagram of the method of the application;

[0029] Figure 2 The figure is a schematic diagram of the determination of the associated moment. DETAILED DESCRIPTION

[0030] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0031] Please refer to Figure 1 The present application provides a single Beidou RTK high-precision positioning method for power line working condition monitoring, comprising the following steps:

[0032] Step one, the position of the reference station calibrated in the power line is determined, and based on the satellite signals received by the reference station, the associated time when the satellite signal strength is the highest is confirmed, and based on the confirmed associated time, the position characteristics of the associated satellite are confirmed. There is a Beidou receiver in the reference station, which receives the satellite signal through an antenna. The antenna has a certain directivity and receiving range. Only when the satellite is within the effective receiving angle range of the antenna, the receiver can receive a stronger signal. Therefore, the strength can be confirmed based on the associated satellite signal in the corresponding direction, the associated time when the satellite signal strength is the highest is locked, and the position is locked based on the corresponding associated time. After the position is locked, the position of the subsequent unmanned aerial vehicle can be effectively positioned in real time, so as to achieve high-precision positioning processing effect. The specific sub-steps for confirming the corresponding position characteristics of the associated satellite are as follows:

[0033] Combined with Figure 2 From the time when the satellite signal of the associated satellite is received from the reference station, the different satellite signals associated in the subsequent different time are received and confirmed;

[0034] Confirm the strength of the received satellite signal: sort the satellite signals confirmed at different times, and sequentially confirm the amplitude of the sorted satellite signals, lock the first group of peak points and the first group of valley points of the corresponding satellite signal. The peak point is the highest amplitude point, and the valley point is the lowest amplitude point. The amplitude associated with the first group of peak points is recorded as F1, and the amplitude associated with the first group of valley points is recorded as F2. The strength parameter FQ associated with the corresponding satellite signal is confirmed by FQ=(F1-F2);

[0035] According to the satellite signals sorted step by step, the associated strength parameter FQ is sorted. From the strength parameter sequence sorted in sequence, the characteristic value is selected, and the strength parameters adjacent to the characteristic value are both smaller than the value (that is, the characteristic value is the peak value in the sorting process, and such peak value is the strongest value of the strength characteristic. The time corresponding to such value is the strongest time). The time corresponding to the characteristic value is recorded as the associated time;

[0036] Mark the satellite signal associated with the associated time as an undetermined signal, confirm the sending time from the undetermined signal (the satellite will give the signal a time stamp when it sends the signal, so the sending time can be directly confirmed), confirm the interval time t between the sending time and the associated time, adopt: V x t = JL lock feature distance, V is a preset value, generally take 299792458 m / s, which is the propagation speed of the signal in the vacuum;

[0037] Based on the location of the reference station and the preset signal receiving direction (the signal receiving direction is determined according to the facing position of the corresponding reference station, which can be directly obtained), taking the location of the base station as the initial point, a set of vectors are constructed, the length of the vector is the feature distance, the vector points in the same direction as the signal receiving direction, and based on the preset rotation angle, the vector is rotated according to the initial point, the preset rotation angle is generally 0.02°, and the spherical region confirmed in the rotation process is taken as the position feature of the associated satellite;

[0038] Specifically, according to the confirmed strongest signal, it is confirmed that the direction of the corresponding signal is relatively consistent with the signal receiving direction, and then based on the corresponding receiving time difference and the transmission rate of the signal, the corresponding feature vector is locked, and based on the starting point and the facing direction determined by the corresponding feature vector, the corresponding feature vector is rotated according to the preset rotation angle, then a space region can be confirmed, which belongs to the position feature of the corresponding satellite, and then the subsequent specific position confirmation can be based on the position feature to achieve the effect of high-precision positioning.

[0039] Step two, dispatch the unmanned aerial vehicle with RTK, and control the unmanned aerial vehicle to receive the signals sent by the associated satellite and the reference station during the flight of the unmanned aerial vehicle, and based on the signal characteristics of the received signals, the position of the unmanned aerial vehicle is preliminarily positioned, and the specific processing method for positioning is:

[0040] Mark the signal received by the unmanned aerial vehicle at the corresponding time as the ground signal, and mark the signal received by the unmanned aerial vehicle at the corresponding time as the air signal;

[0041] Confirm the feature time difference associated with the ground signal at the corresponding time, lock the sending time of the ground signal and mark it as T1, and then mark the corresponding time as T2, adopt: Feature time difference = |T1-T2| to confirm the feature time difference, and adopt: Feature time difference x V = ground distance to confirm the ground distance between the unmanned aerial vehicle and the reference station, V is a preset value, generally take 299792458 m / s;

[0042] Confirm the feature time difference associated with the air signal at the corresponding time, lock the sending time of the air signal and the corresponding time, confirm the corresponding feature time difference, and then lock the air distance between the UAV and the associated satellite in combination with the preset speed V;

[0043] Based on the confirmed ground distance and the location of the reference station, the location of the reference station is taken as the center of the circle, and the ground distance is taken as the radius to confirm a group of spherical regions (based on the confirmed center and the corresponding radius, a group of spherical regions can be locked in three-dimensional space, and the points on the spherical region circle surface are all possible UAV location points based on the point feature determined by the corresponding signal feature);

[0044] Based on the position feature confirmed by the associated satellite, a feature point is randomly locked from the position feature, and the straight line distance between the feature point and any point in the spherical region is confirmed. The point with the same straight line distance as the air distance is recorded as the positioning point, and the confirmed positioning points are marked in the spherical region. Different positioning points associated with different feature points are different, so there are multiple positioning points in the spherical region.

[0045] Specifically, after the specific position feature of the air satellite is confirmed, the subsequent position point confirmation can be based on the specific feature of the UAV in the actual flight process. Based on the confirmed position point, the positioning points existing in the spherical region are confirmed. There can be multiple groups of positioning points. In order to achieve high-precision positioning, the position feature of the adjacent time is confirmed, and the high-precision positioning point is determined based on the flight direction of the UAV.

[0046] Step three, based on the positioning data associated in the preliminary positioning process of the UAV, the positioning data associated in the next time is confirmed, and the high-precision positioning process of the UAV is completed based on the data features of the positioning data between adjacent times and the flight direction of the UAV. The data of real-time positioning and monitoring data are bundled to generate a bundled data package for display, and the specific way to complete the high-precision positioning process is:

[0047] The positioning data confirmed in the last group of time (the corresponding time in step two) is taken as the initial data, and the positioning data includes the spherical region and the marked positioning point.

[0048] The same processing method as step two is used to confirm the positioning data associated with the current time as verification data.

[0049] The initial data is marked as an initial point, the verification data is marked as a verification point, the flight direction of the unmanned aerial vehicle is marked as a reference direction, the initial point is selected, and the initial point is moved according to the reference direction, and it is determined whether there is a verification point completely coinciding with the initial point in the moving process, if there is, the initial point and the verification point are marked as high-precision positioning points, if not, the confirmation is continued until the high-precision positioning points are confirmed;

[0050] When positioning subsequently, the high-precision positioning points determined at the previous moment are started, and the high-precision positioning points are locked from the positioning points confirmed at the next moment according to the reference direction, and the corresponding working condition data and positioning data monitored by the unmanned aerial vehicle are bundled based on the real-time high-precision positioning process, and the bundled data packet is confirmed and displayed.

[0051] Specifically, there are two groups of continuous moments, in the previous moment, there are a plurality of positioning points marked, and in the next moment, there are associated positioning points, the positioning points of the previous moment are initial points, and the positioning points of the next moment are verification points, the corresponding flight direction is based on the corresponding initial point, and the corresponding flight direction can confirm the subsequent verification point, the initial point and the verification point are the confirmed high-precision positioning points, so that the corresponding bundled data packet can be confirmed based on the corresponding high-precision positioning points and the actual working condition monitoring data.

[0052] Part of the data in the above formula is dimensionless numerical calculation, and the contents not described in detail in the specification all belong to the prior art known to those skilled in the art.

[0053] The above embodiments are only used to illustrate the technical method of the present application and are not limited, although the present application is described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical method of the present application.

Claims

1. A single Beidou RTK high-precision positioning method for power line working condition monitoring, characterized in that, Comprise the following steps: Step one, the position of the calibration station in the transmission line is determined, and based on the satellite signal received by the reference station, the associated time of the highest satellite signal strength is confirmed, and based on the confirmed associated time, the position characteristics of the associated satellite are confirmed; Step two, the unmanned aerial vehicle with RTK is dispatched, and in the process of flight, the unmanned aerial vehicle receives the signals sent by the associated satellite and the reference station, and based on the signal characteristics of the received signals, the position of the unmanned aerial vehicle is preliminarily positioned; Step three, based on the positioning data associated in the preliminary positioning process of the unmanned aerial vehicle, the positioning data associated in the next moment is confirmed, and based on the data characteristics of the positioning data between adjacent moments and the flight direction of the unmanned aerial vehicle, the high-precision positioning process of the unmanned aerial vehicle is completed, and the real-time positioning data is bundled with the monitoring data to generate a bundled data package for display.

2. The single Beidou RTK high-precision positioning method for power transmission line working condition monitoring according to claim 1, characterized in that, In step one, the specific way to confirm the associated time is: From the moment when the reference station receives the satellite signal of the associated satellite, the satellite signals associated in the subsequent different moments are received and confirmed; Confirm the strength of the received satellite signal: sort the satellite signals confirmed at different times, and sequentially confirm the amplitude of the sorted satellite signals, lock the first group of peak points and the first group of valley points of the corresponding satellite signal, the peak point is the highest amplitude point, and the valley point is the lowest amplitude point, record the amplitude associated with the first group of peak points as F1, and record the amplitude associated with the first group of valley points as F2, and confirm the strength parameter FQ associated with the corresponding satellite signal by using: FQ=(F1-F2); According to the gradually sorted satellite signals, the associated strength parameter FQ is sorted, and from the sequence of the sorted strength parameters, the characteristic value is selected, and the strength parameters before and after the characteristic value are both less than the value, and the time corresponding to the characteristic value is recorded as the associated time.

3. The single Beidou RTK high-precision positioning method for power transmission line working condition monitoring according to claim 2, characterized in that, In step one, the specific way to confirm the position characteristics of the associated satellite is: Record the satellite signal associated with the associated time as the undetermined signal, confirm the interval time t between the sending time and the associated time from the undetermined signal, lock the characteristic distance by using: Vxt=JL, wherein V is a preset value; Based on the position of the reference station and the preset signal receiving direction, a group of vectors are constructed with the position of the reference station as the initial point, the length of the vector is the characteristic distance, the vector points in the same direction as the signal receiving direction, and based on the preset swing angle, the vector rotates around the initial point, and the spherical region confirmed in the rotation process is taken as the position characteristics of the associated satellite.

4. The single Beidou RTK high-precision positioning method for power transmission line condition monitoring according to claim 1, characterized in that, In step two, the specific way to position the position of the unmanned aerial vehicle is: Record the signal received by the unmanned aerial vehicle at the corresponding moment as the ground signal, and record the signal received by the unmanned aerial vehicle at the corresponding moment as the air signal; Confirm the feature time difference associated with the ground signal at the corresponding time, lock the sending time of the ground signal and mark it as T1, then mark the corresponding time as T2, confirm the feature time difference by: feature time difference = |T1-T2|, and confirm the ground distance between the UAV and the reference station by: feature time difference x V = ground distance, where V is a preset value; Confirm the feature time difference associated with the air signal at the corresponding time, lock the sending time of the air signal and the corresponding time, confirm the corresponding feature time difference, and then lock the air distance between the UAV and the associated satellite in combination with the preset speed V; Based on the confirmed ground distance and the location of the reference station, take the location of the reference station as the center of the circle and the ground distance as the radius to confirm a group of spherical regions; Based on the location features confirmed by the associated satellite, randomly lock feature points from the location features and confirm the straight-line distance between the feature points and any point in the spherical region. Mark the point with the same straight-line distance as the air distance as the positioning point, and mark the confirmed positioning points in the spherical region.

5. The single Beidou RTK high-precision positioning method for power transmission line working condition monitoring according to claim 4, characterized in that, The positioning points associated with different feature points are different, so there are multiple positioning points in the spherical region.

6. The single Beidou RTK high-precision positioning method for power transmission line condition monitoring according to claim 1, characterized in that, In step three, the specific way to complete the high-precision positioning process of the UAV is: Take the positioning data confirmed at the previous group of times as the initial data, which includes the spherical region and the marked positioning points; Use the same processing method as step two to confirm the positioning data associated with the current time as verification data; Mark the several positioning points marked in the initial data as initial points, the several positioning points marked in the verification data as verification points, and the flight direction of the UAV as the reference direction. Select the initial points one by one and move them according to the reference direction determined based on the confirmed reference direction. Determine whether there is a verification point that completely coincides with the initial point in the moving process. If there is, mark both the initial point and the verification point as high-precision positioning points. If not, continue to confirm until a high-precision positioning point is confirmed. When positioning subsequently, start from the high-precision positioning point determined at the previous time and lock the high-precision positioning point from the positioning points confirmed at the next time according to the reference direction to complete the high-precision positioning process.

7. The single Beidou RTK high-precision positioning method for power transmission line working condition monitoring according to claim 6, characterized in that, In step three, based on the real-time high-precision positioning process, bundle the working condition data and positioning data monitored by the corresponding UAV to confirm the bundled data package for display.

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