A floating wind measurement laser radar device and attitude compensation method

Abstract

The application discloses a floating wind measurement laser radar device and a posture compensation method, and the device comprises a wind measurement laser radar, a two-axis stabilizing platform and a floating body, wherein: the wind measurement laser radar carries out wind field measurement in multiple scanning modes through a 3D servo scanning system and a mainframe box embedded with the posture compensation method, including DBS, VAD, PPI and RHI, and can realize multiple offshore wind farm measurement application scenarios including wind profile wind field measurement and wind turbine wake measurement; the wind measurement laser radar is carried on the two-axis stabilizing platform, the influence of the floating body movement can be isolated through the two-axis stabilizing platform, the pointing of the scanning beam of the wind measurement laser radar is kept stable, the subsequent posture compensation of the wind measurement data of the laser radar does not need to consider the rotation factor any more, only needs to consider the translation factor, the posture compensation algorithm in different wind field measurement scenarios is simplified, and the background calculation amount is reduced.

Description

Technical Field

[0001] This invention relates to the field of marine wind measurement technology, specifically to a floating wind measurement lidar device and attitude compensation method. Background Technology

[0002] Doppler wind lidar, as a novel marine atmospheric wind field detection technology, meets the relevant needs of the offshore wind power industry in wind resource assessment and has been widely adopted. Compared with fixed offshore wind measurement towers, floating observation platforms provide a flexible, efficient, and low-cost means of measuring marine wind fields, enabling applications in various measurement scenarios such as vertical wind profiles, natural inflows and wakes of wind turbines. Floating wind lidar is obtained by installing traditional land-based stable platform wind lidar on offshore floating platforms, buoys, or ship hulls (collectively referred to as floating bodies) and making corresponding adaptive modifications such as wind measurement attitude correction.

[0003] The existing floating wind measurement lidar has the following shortcomings: (1) Most wind measurement lidars installed on floating bodies are optical wedge scanning lidars, which can only perform DBS (Doppler-beam-swinging) scanning to obtain the horizontal wind field of the wind profile. The scanning mode and application scenarios are relatively simple; (2) Since the lidar and the floating body are rigidly connected, the lidar measurement process will be affected by the attitude interference of the floating body's rotation and translation; (3) In order to eliminate the attitude interference of the floating body, a relatively complex attitude compensation algorithm is required, which puts forward high requirements on the design of the attitude compensation algorithm and the background calculation process. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the shortcomings of existing floating wind measurement lidar in terms of measurement scenarios and attitude compensation, thereby providing a floating wind measurement lidar device and attitude compensation method.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] In a first aspect, embodiments of the present invention provide a floating wind-measuring lidar device, comprising: a wind-measuring lidar, a two-axis stabilized platform, and a float, wherein:

[0007] The wind-measuring lidar uses a 3D servo scanning system and a main unit with an embedded attitude compensation method to perform wind field measurements in various scanning modes. The main unit is electrically connected to the first control box, which provides power, stores data, and performs related remote control operations for the wind-measuring lidar.

[0008] The main unit is fixed on the support platform of the two-axis stabilization platform and connected to the roll axis system of the two-axis stabilization platform via a connecting bracket. The roll axis system is connected to the roll motor, and the roll angle is stabilized in real time by a roll angle measuring device built into the roll motor. The roll motor is mounted on the pitch frame and connected to the pitch axis system via the pitch frame. The pitch axis system is connected to the pitch motor, and the pitch angle is stabilized in real time by a pitch angle measuring device built into the pitch motor. The roll motor and pitch motor of the two-axis stabilization platform are electrically connected to the second control box. The second control box provides power supply, data storage, and related remote control operations for the two-axis stabilization platform. The pitch motor is connected to the base platform via a bracket, and the base platform is fixed on the float.

[0009] In one embodiment, the wind field measurement using the various scanning methods includes DBS, VAD, PPI, and RHI, and the acquired wind measurement elements of the offshore wind farm include: vertical wind profile wind field, horizontal profile of wind turbine wake, and vertical profile.

[0010] In one embodiment, remote operation of the wind-measuring lidar includes: turning the wind-measuring lidar on and off, setting the scanning mode and other measurement parameters.

[0011] In one embodiment, the control device includes: a control cabinet and a control computer. The gas alarm controller transmits data to the control computer for data calculation, processing, and data model comparison, and transmits the data to the cloud. At the same time, it generates control commands based on the processing results and performs safety interlock control through the control cabinet.

[0012] In one embodiment, remote operation of the two-axis stabilized platform includes: initial roll and pitch angle settings, and response sensitivity of the roll and pitch motors.

[0013] In one embodiment, an inertial navigation system consisting of an inertial rate element and an inertial position element is provided in both the roll motor and the pitch motor. The control inner loop of the two-axis stabilization platform is formed by the velocity closed loop by the inertial rate element and the position closed loop by the inertial position element collecting the platform's angular position information.

[0014] In one embodiment, the two-axis stabilization platform control algorithm adopts a PID control algorithm, which compares the real-time measured roll and pitch angles with the preset roll and pitch angles to perform real-time negative feedback control on the roll and pitch motors.

[0015] Secondly, embodiments of the present invention provide an attitude compensation method for a floating wind-measuring lidar, based on the floating wind-measuring lidar device described in the first aspect, comprising: performing DBS scanning to invert the wind profile wind field attitude compensation, specifically:

[0016] During a DBS four-beam scanning cycle, the average vertical translational velocity V of the lidar in each of the four scanning directions is obtained through the inertial navigation system. z Multiplying this by the average scanning dwell time Δt for each beam yields the vertical displacement compensation Δz = V for the scanning beams in the four directions. z ×Δt;

[0017] Vertical displacement compensation is considered for each measurement distance gate of the scanning beam: taking the upward vertical displacement as positive, when the float is instantaneously above the sea level, i.e. Δz is greater than 0, the height of each distance gate of the scanning beam is subtracted by Δz; when the float is instantaneously below the sea level, i.e. Δz is less than 0, the height of each distance gate of the scanning beam is subtracted by Δz. By compensating for the vertical displacement of each distance gate of the four scanning beams, the exit point of each beam in one DBS scanning cycle is leveled to the initial sea level height.

[0018] In one DBS scan cycle, the lowest distance gate of the beam closest to sea level is selected. This vertical height is used as the reference for interpolating the distance gates of other beams. The wind speed and direction at each distance gate height after interpolation are then calculated using a conventional DBS algorithm. Combined with the real-time three-axis translational velocity measured by the inertial navigation system, the true wind speed vector at each distance gate height in one DBS scan cycle is calculated, as shown in the following formula:

[0019] V true =V obs +V mot

[0020] Among them, V true V is the wind speed vector in the geodetic reference coordinate system. obs V is the wind speed vector measured in the lidar reference coordinate system. mot This represents the translational velocity vector of the lidar relative to the geodetic coordinate system.

[0021] In one embodiment, the DBS algorithm is a special case of the VAD algorithm. The attitude compensation process of DBS wind profile scanning to retrieve the horizontal wind field is analogized to the VAD algorithm: In a VAD scanning cycle of a wind-measuring lidar, vertical displacement compensation is performed on each scanning laser beam. Considering only the three-axis translational velocity, the true radial wind speed relative to the geodetic coordinate system can be obtained.

[0022] In one embodiment, the attitude compensation method further includes: performing horizontal PPI and vertical RHI fan-shaped scanning to obtain attitude compensation for radial wind speed, wherein:

[0023] When a wind-measuring lidar performs a horizontal PPI scan, given the following: beam pointing azimuth angle θ, and translational velocity V along the x-axis... x Translational velocity V along the y-axis yBy calculating the time step Δt, the length ΔL of the radial displacement of line segment OP can be calculated, thus obtaining the radial displacement compensation for each laser beam in PPI scanning mode.

[0024] When performing vertical RHI scanning, the wind-measuring lidar calculates the radial displacement compensation for each laser beam in a similar manner to that used for horizontal PPI scanning. For each laser beam in a single RHI scanning cycle: when the RHI scanning direction is defined as the positive x-axis and the vertical upward direction is defined as the positive z-axis, the radial displacement compensation for each RHI scanning laser beam can be obtained based on the lengths of the translational displacements in the x-axis and z-axis directions.

[0025] In one embodiment, when using the low-elevation PPI scan results of a floating wind lidar device to perform VAD horizontal wind field inversion, the attitude compensation for VAD horizontal wind field inversion is performed according to the following steps, with the initial PPI scan laser beam OA as a reference:

[0026] After radial linear displacement compensation of the laser beam at each azimuth angle in a PPI scanning cycle, it is necessary to use the height of each distance gate of the OA beam as a reference to find the beam position in the subsequent PPI scanning beam whose height corresponds to the height of each distance gate of the OA beam. Based on the rotational isolation effect of the two-axis stabilization platform, the pitch angle of the subsequent PPI scanning beam is the same as that of the OA beam. The beam position on the subsequent scanning beam corresponding to the height of each distance gate of the OA beam can be deduced by using the height and pitch angle of different distance gate positions of the OA beam.

[0027] By using inverse distance weighted interpolation, the radial wind speed at the corresponding point of each distance gate height of the OA beam can be calculated from the measured radial wind speed of two adjacent distance gates on a certain PPI scanning beam. Thus, the radial wind speed in the other scanning directions corresponding to each distance gate height of the OA beam in one PPI scanning cycle can be obtained.

[0028] After obtaining the radial wind speeds at equal heights in all directions during a PPI scan cycle, the horizontal wind field at different vertical heights is inverted using the conventional VAD algorithm.

[0029] The technical solution of this invention has the following advantages:

[0030] This invention provides a floating wind-measuring lidar device and attitude compensation method. The floating wind-measuring lidar has multiple scanning modes, including DBS, VAD, PPI, and RHI, and can realize various offshore wind farm measurement applications, such as wind profile wind field, vertical profile and horizontal profile measurement of wind turbine wake. The two-axis stabilization platform can isolate the influence of the floating body's motion and maintain the pointing stability of the wind-measuring lidar scanning beam. Since the two-axis stabilization platform isolates the influence of the floating body's rotation, the subsequent attitude compensation of the lidar wind measurement data does not need to consider the rotation factor, but only the translation factor, which simplifies the attitude compensation algorithm under different wind field measurement scenarios and reduces the amount of backend computation. Attached Figure Description

[0031] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of a floating wind-measuring lidar device in an embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of the single-axis control structure of the two-axis stabilization platform in an embodiment of the present invention;

[0034] Figure 3 (A) and 3(B) are schematic diagrams of the DBS scanning laser beam and distance gate of the scanning wind-measuring lidar in the embodiments of the present invention when there is no horizontal displacement and when there is horizontal displacement, respectively.

[0035] Figure 4 This is a schematic diagram of the movement of the wind-measuring lidar beam mounted on a two-axis stabilizing platform of a floating body in an embodiment of the present invention.

[0036] Figure Labels

[0037] 1-3D servo scanning system; 2-Main chassis; 3-First connecting cable; 4-First control box; 5-Support platform; 6-Connecting bracket; 7-Roll motor; 8-Roll axis system; 9-Pitch frame; 10-Pitch motor; 11-Pitch axis system; 12-Second connecting cable; 13-Second control box; 14-Bracket; 15-Base platform; 16-Float body. Detailed Implementation

[0038] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0040] Example 1

[0041] This invention provides an attitude compensation method and apparatus for a floating wind-measuring lidar, specifically including: a wind-measuring lidar, a two-axis stabilized platform, and a float, such as... Figure 1 As shown, the wind-measuring lidar uses a 3D servo scanning system (1) and a main unit (2) with an embedded attitude compensation method to perform wind field measurements in various scanning modes. The main unit (2) is electrically connected to a first control box (4) that integrates the wind-measuring lidar power supply, data storage device and control device, so as to realize the power supply, data storage and related remote control operations of the wind-measuring lidar.

[0042] Wind-measuring lidar can perform various measurement methods, including DBS (Doppler-beam-swinging), VAD (Velocity-azimuth-display), PPI (Plan Position Indicator), and RHI (Range Height Indicator), and can be applied to various marine wind measurement scenarios such as vertical wind profile wind fields, horizontal and vertical profiles of wind turbine wakes.

[0043] In this embodiment of the invention, the main unit (2) is electrically connected to the first control box (4) via power lines, data transmission lines, and control lines. In practice, these lines can be packaged together, such as... Figure 1 The first connecting line (3) shown in the figure; remote operation of the wind measuring lidar includes: switching the wind measuring lidar on and off, setting the scanning mode and other measurement parameters.

[0044] The main unit (2) is fixed on the support platform (5) of the two-axis stabilization platform and connected to the roll axis system (8) of the two-axis stabilization platform via a connecting bracket (6). The roll axis system (8) is connected to the roll motor (7), and the roll angle is controlled in real time by a roll angle measuring device (e.g., a potentiometer) built into the roll motor (7). The roll motor (7) is mounted on the pitch frame (9) and connected to the pitch axis system (11) via the pitch frame (9). The pitch axis system (11) is connected to the pitch motor. (10) are connected and the pitch angle is stabilized in real time through the pitch angle measuring device (e.g., potentiometer) built into the pitch motor. The roll motor (7) and pitch motor (10) of the two-axis stabilized platform are connected to the second control box (13) which integrates power supply, data storage device and control device to realize power supply, data storage and related remote control operation of the two-axis stabilized platform. The pitch motor is connected to the base platform (15) through the bracket (14) and the base platform is fixed on the float (16).

[0045] In this embodiment of the invention, electrical connection is achieved with the second control box (13) via power lines, data transmission lines, and control lines. In practice, these lines can be packaged together, such as... Figure 1 The second connecting line (12) shown in the figure.

[0046] The floating wind-measuring lidar device proposed in this invention embodiment incorporates an inertial navigation system consisting of inertial rate elements and inertial position elements within both the roll and pitch motors. The inner loop of the two-axis stabilized platform control structure forms a velocity closed loop using inertial rate elements to suppress interference from changes in the roll and pitch angular velocities of the floating body, ensuring system stability. The outer loop uses inertial position elements to collect platform angular position information, forming a position closed loop to eliminate position deviations. Regarding the two-axis stabilized platform control algorithm, a PID (Proportional Integral Derivative) control algorithm is employed. By comparing the real-time measured roll and pitch angles with pre-set roll and pitch angles, real-time negative feedback control of the roll and pitch motors is achieved, maintaining the stability of the wind-measuring lidar's emitted beam direction. The single-axis control structure of the two-axis stabilized platform is as follows: Figure 2 As shown. Based on the above control, the device provided in this embodiment of the invention controls the movement of the two-axis stabilizing platform in the opposite direction to the attitude change of the floating body by measuring the attitude change of the floating body in real time, thereby isolating the floating body disturbance, stabilizing the platform relative to the inertial coordinate system, and thus keeping the output direction of the wind-measuring lidar beam stable.

[0047] Example 2

[0048] This invention provides an attitude compensation method for a floating wind-measuring lidar, applied to the main chassis of the wind-measuring lidar in the floating wind-measuring lidar device of Embodiment 1. The compensation methods for different scanning modes are as follows:

[0049] 1. DBS wind profile scanning is used to invert the attitude compensation of the horizontal wind field.

[0050] For wind-measuring lidar, when fixed on a two-axis stabilized platform, the platform isolates the float's three-axis rotation in real time, allowing the emitted laser beam to maintain a fixed azimuth and elevation angle. In this scenario, the lidar is only affected by the horizontal (x and y-axis directions) and vertical translational displacements of the float. According to the spatial vector superposition principle of the DBS algorithm, horizontal (x and y-axis directions) displacement does not affect radial wind speed. Only vertical displacement compensation is needed for the radial wind speed of each laser beam's range gate after vertical (z-axis) displacement. Subsequently, inverse distance weighting interpolation is performed on the radial wind speed of each range gate for the four beams in one DBS scan cycle to achieve alignment of the four beams' range gates in the z-axis direction.

[0051] The specific calculation process is as follows: During one DBS four-beam scanning cycle, the average vertical translational velocity V in the four scanning directions is obtained through the inertial navigation system. z Multiplying this by the average scanning dwell time Δt for each beam yields the vertical displacement compensation Δz = V for the scanning beams in the four directions. z ×Δt. Vertical displacement compensation is considered for each measurement range gate of the scanning beam: taking upward vertical displacement as positive, when Δz is greater than 0 (i.e., the float is instantaneously above sea level), the height of each range gate of the beam is subtracted by Δz; when Δz is less than 0 (i.e., the float is instantaneously below sea level), the height of each range gate of the beam is subtracted by Δz. By compensating for the vertical displacement of the four beam range gates in the z-axis direction, the exit points of all beams are aligned with the initial sea level height.

[0052] Figure 3 Figures (A) and (B) are schematic diagrams of DBS four-beam laser scanning on a two-axis stabilized platform with and without horizontal displacement, respectively. Rays a, b, c, and d represent laser beams, and the dashed lines represent range gates. With horizontal displacement, laser beam a represents the instantaneous downward vertical displacement of the float along the z-axis, laser beam c represents the instantaneous backward horizontal displacement of the float along the x-axis, and laser beams b and c represent no displacement.

[0053] Among the four beams, the lowest distance gate of the beam closest to sea level is selected. This vertical height is used as the reference for interpolating the distance gates of the other beams. Then, using the conventional DBS algorithm, the observed wind speed vectors for each distance gate of the scanned beams in each direction after interpolation can be obtained. Since the wind-measuring lidar in this embodiment is deployed on a two-axis stabilized platform, the rotational interference of the floating body does not need to be considered. Only the real-time three-axis translational velocity vector measured by the inertial navigation system needs to be combined to calculate the true wind speed vectors at different distance gate heights for each beam, as shown in the following formula:

[0054] V true＝ V obs +V mot

[0055] Among them, V true V is the wind speed vector in the geodetic reference coordinate system. obs V is the wind speed vector measured in the lidar reference coordinate system. mot This represents the translational velocity vector of the lidar relative to the geodetic coordinate system.

[0056] Furthermore, since the DBS algorithm is a special case of the VAD algorithm, the idea of ​​DBS scanning attitude compensation applicable to two-axis stabilized platforms can be analogized to the VAD algorithm. That is, in a wind-measuring lidar VAD scanning cycle, vertical displacement compensation is performed on each scanning laser beam. Considering only the three-axis translational velocity of the floating body, the true radial wind speed relative to the geodetic coordinate system can be obtained.

[0057] 2. Horizontal PPI and vertical RHI sector scanning to obtain radial wind speed attitude compensation.

[0058] like Figure 4 As shown, when the scanning lidar is performing a horizontal PPI scan, given the following: beam pointing azimuth angle θ, x-axis translational speed V... x Translational speed V along the y-axis y Given a time step Δt, the radial displacement compensation for each laser beam in PPI scanning mode can be obtained simply by calculating the length ΔL of line segment OP. O is the initial position of the lidar; O' is the lidar position after translational displacement; OA is the original scanning beam direction; O'A' is the beam direction after translational displacement; θ is the azimuth angle of the stable laser beam direction (relative to due east, i.e., the x-axis). O' is the azimuth angle of OO' relative to due east; O'P is perpendicular to OA.

[0059] Further:

[0060] Therefore there is

[0061] and

[0062] Furthermore:

[0063]

[0064] The above describes the horizontal displacement compensation analysis for PPI scanning using a lidar system. When performing a vertical RHI scan, a similar approach can be used to calculate the radial displacement compensation for each RHI scan laser beam: for each RHI scan laser beam, when the RHI scan direction is defined as the positive x-axis and the vertically upward direction as the positive z-axis, only the translational displacements in the x-axis and z-axis directions need to be considered. (Refer to...) Figure 4 At this point, the calculated |OP| is the radial linear displacement compensation for each RHI scanning laser beam.

[0065] 3. Low elevation angle PPI scan to retrieve attitude compensation for horizontal wind field inversion.

[0066] When using the low-elevation PPI scan results of the floating wind lidar device described in this invention to perform VAD horizontal wind field inversion, the initial PPI scan laser beam OA is used as a reference (e.g., Figure 4 As shown), perform attitude compensation for VAD horizontal wind field inversion according to the following steps:

[0067] 1) After radial linear displacement compensation of the laser beams at different PPI scanning azimuth angles, it is necessary to use the height of each distance gate of the OA beam (i.e., h = Δl × sinδ, where h is the height of each distance gate of the OA beam relative to the horizontal plane, Δl is the radial length, and δ is the pitch angle of the PPI scan).

[0068] 2) Locate the beam points in the subsequent PPI scanning beam whose heights correspond to the gate heights of the OA beam. Due to the rotational isolation effect of the two-axis stabilizing platform, the pitch angle of the subsequent PPI scanning beam is the same as that of the OA beam. The beam points in the subsequent scanning beam corresponding to the gate heights of the OA beam are deduced from the height h and pitch angle δ of the OA beam at different gate heights, i.e., Δl = h / sinδ.

[0069] 3) Generally, the points corresponding to each height on the subsequent PPI scanning laser beam obtained through step 2) will not be exactly the measurement distance gate positions of the subsequent beam, but rather positions between two adjacent measurement distance gates of the subsequent beam. Therefore, it is necessary to use the inverse distance weighting interpolation method to calculate the radial wind speed at each height corresponding to the points from the measured radial wind speeds of the distance gates on both sides. Thus, the radial wind speeds in the remaining PPI scanning directions corresponding to each distance gate height (e.g., 5m, 10m, 15m…) of the OA beam can be obtained.

[0070] 4) After obtaining the radial wind speeds at equal heights in each direction during a PPI scan cycle, the horizontal wind field parameters (wind speed and wind direction) at different vertical heights are inverted according to the conventional VAD algorithm.

[0071] As can be seen from the above attitude compensation methods, since the floating wind lidar device isolates the rotational attitude interference of the floating body, only the translational factors need to be considered, which can simplify the wind lidar attitude compensation algorithm and reduce the amount of backend computation.

[0072] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An attitude compensation method for a floating wind-measuring lidar, applied to the main chassis of the wind-measuring lidar in a floating wind-measuring lidar device, characterized in that, include: DBS scanning is performed to retrieve attitude compensation for the wind field in the wind profile, specifically as follows: During a DBS four-beam scanning cycle, the average vertical translational velocity of the lidar in each of the four scanning directions is obtained through the inertial navigation system. V z Multiply by the average scan dwell time Δ for each beam t That is, to obtain the vertical displacement compensation Δ for the scanning beams in four directions. z = V z ×Δ t ; For each measurement distance gate of the scanning beam, vertical displacement compensation is considered: taking upward vertical displacement as positive, when the buoy is instantaneously above sea level, i.e., Δ z If the value is greater than 0, subtract Δ from the height of each distance gate of the scanning beam. z When the floating body momentarily drops below sea level, i.e., Δ z If the value is less than 0, subtract Δ from the height of each distance gate of the scanning beam. z By compensating for the vertical displacement of each distance gate of the four scanning beams, the exit point of each beam in one DBS scanning cycle is leveled to the initial sea level height. In one DBS scan cycle, the lowest distance gate of the beam closest to sea level is selected. This vertical height is used as the reference for interpolating the distance gates of other beams. The wind speed and direction at each distance gate height after interpolation are then calculated using a conventional DBS algorithm. Combined with the real-time three-axis translational velocity measured by the inertial navigation system, the true wind speed vector at each distance gate height in one DBS scan cycle is calculated, as shown in the following formula: V true =V obs +V mot Among them, V true V is the wind speed vector in the geodetic reference coordinate system. obs V is the wind speed vector measured in the lidar reference coordinate system. mot This represents the translational velocity vector of the lidar relative to the geodetic coordinate system.

2. The attitude compensation method for a floating wind-measuring lidar according to claim 1, characterized in that, The DBS algorithm is a special case of the VAD algorithm. The attitude compensation process of DBS wind profile scanning to retrieve the horizontal wind field is analogized to the VAD algorithm: In a VAD scanning cycle of a wind-measuring lidar, vertical displacement compensation is performed on each scanning laser beam. Considering only the three-axis translational velocity, the true radial wind speed relative to the geodetic coordinate system can be obtained.

3. The attitude compensation method for a floating wind-measuring lidar according to claim 2, characterized in that, Also includes: Horizontal PPI and vertical RHI sector scans are performed to obtain radial wind speed attitude compensation, wherein: When a wind-measuring lidar performs a horizontal PPI scan, it has a known beam pointing azimuth angle. θ Translational velocity along the x-axis V x Translational velocity along the y-axis V y Calculate the time step Δ t In this case, the length Δ of line segment OP, i.e., the radial linear displacement, can be calculated. L This allows us to obtain radial displacement compensation for each laser beam in PPI scanning mode; When performing vertical RHI scanning, the wind-measuring lidar calculates radial linear displacement compensation for each laser beam in a similar manner to that used in horizontal PPI scanning. For each laser beam in a RHI scanning cycle: when the RHI scanning direction is defined as the positive x-axis and the vertical upward direction is defined as the positive z-axis, the radial displacement compensation of each RHI scanning laser beam can be obtained based on the length of the translational displacement in the x-axis and z-axis directions.

4. The attitude compensation method for a floating wind-measuring lidar according to claim 3, characterized in that, When using the low-elevation PPI scan results of a floating wind lidar device to perform VAD horizontal wind field inversion, the attitude compensation for VAD horizontal wind field inversion is performed according to the following steps, with the initial PPI scan laser beam OA as a reference: After radial linear displacement compensation of the laser beam at each azimuth angle in a PPI scanning cycle, it is necessary to use the height of each distance gate of the OA beam as a reference to find the beam position in the subsequent PPI scanning beam whose height corresponds to the height of each distance gate of the OA beam. Based on the rotational isolation effect of the two-axis stabilization platform, the pitch angle of the subsequent PPI scanning beam is the same as that of the OA beam. The beam position on the subsequent scanning beam corresponding to the height of each distance gate of the OA beam can be deduced by using the height and pitch angle of different distance gate positions of the OA beam. By using inverse distance weighted interpolation, the radial wind speed at the corresponding point of each distance gate height of the OA beam can be calculated from the measured radial wind speed of two adjacent distance gates on a certain PPI scanning beam. Thus, the radial wind speed in the other scanning directions corresponding to each distance gate height of the OA beam in one PPI scanning cycle can be obtained. After obtaining the radial wind speeds at equal heights in all directions during a PPI scan cycle, the horizontal wind field at different vertical heights is inverted using the conventional VAD algorithm.

5. A floating wind-measuring lidar device, characterized in that, include: The system includes a wind-measuring lidar, a two-axis stabilized platform, and a floating body, among which: The wind-measuring lidar uses a 3D servo scanning system and a main unit housing embedded with the attitude compensation method described in any one of claims 1-4 to perform wind field measurements in various scanning modes. The main unit housing is electrically connected to the first control box, which provides power supply, data storage, and related remote control operations to the wind-measuring lidar. The main unit is fixed on the support platform of the two-axis stabilization platform and connected to the roll axis system of the two-axis stabilization platform via a connecting bracket. The roll axis system is connected to the roll motor, and the roll angle is stabilized in real time by a roll angle measuring device built into the roll motor. The roll motor is mounted on the pitch frame and connected to the pitch axis system via the pitch frame. The pitch axis system is connected to the pitch motor, and the pitch angle is stabilized in real time by a pitch angle measuring device built into the pitch motor. The roll motor and pitch motor of the two-axis stabilization platform are electrically connected through a second control box for power supply, data storage, and related remote control operations of the two-axis stabilization platform. The pitch motor is connected to the base platform via a bracket, and the base platform is fixed on the float.

6. The floating wind-measuring lidar device according to claim 5, characterized in that, Multiple scanning measurement methods are used, including DBS, VAD, PPI, and RHI. Various wind measurement elements of offshore wind farms are obtained, including vertical wind profile wind field, horizontal and vertical profiles of wind turbine wake.

7. The floating wind-measuring lidar device according to claim 5, characterized in that, Remote operation of the wind-measuring lidar includes: turning the wind-measuring lidar on and off, setting the scanning mode, and other measurement parameters.

8. The floating wind-measuring lidar device according to claim 5, characterized in that, Remote operation of a two-axis stabilized platform includes: initial roll and pitch angles, and response sensitivity of the roll and pitch motors.

9. The floating wind-measuring lidar device according to claim 5, characterized in that, Both the roll motor and the pitch motor are equipped with an inertial navigation system consisting of an inertial rate element and an inertial position element. The control inner loop of the two-axis stabilizing platform is formed by the velocity closed loop of the inertial rate element and the position closed loop of the platform by the inertial position element collecting the angular position information of the platform.

10. The floating wind-measuring lidar device according to claim 9, characterized in that, The two-axis stabilization platform control algorithm adopts the PID control algorithm, which compares the real-time measured roll and pitch angles with the preset roll and pitch angles to perform real-time negative feedback control of the roll and pitch motors.

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