A dual-antenna positioning error correction method based on attitude sensing data

Abstract

The present invention provides a method for correcting the positioning error of a dual-antenna based on attitude sensing data, which includes installing a main antenna A, a secondary antenna B, and an attitude sensor on the nacelle at the top of the wind turbine tower; then controlling the rotation of the wind turbine nacelle to obtain the initial coordinates of the nacelle rotation center when the wind turbine rotor stops rotating; during the operation of the wind turbine, obtaining the horizontal offset of the nacelle rotation center through the position changes of the main antenna A and the secondary antenna B; at the same time, obtaining the horizontal offset of the wind turbine tower through the attitude sensor; when the difference between the two is greater than the set correction threshold, using the horizontal offset of the wind turbine tower obtained by the attitude sensor to replace and correct the horizontal offset of the nacelle rotation center. The replacement correction method in the present invention can avoid the abnormal data mutation that occurs intermittently in the high-frequency differential resolution of the Beidou dual-antenna receiver, reduce the positioning error, and is conducive to reflecting the true tilt state of the wind turbine tower.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power monitoring, and in particular to a dual-antenna positioning error correction method based on attitude sensing data. Background Art

[0002] As a pollution-free, renewable green energy, wind energy is of great significance in solving the global energy crisis and environmental crisis. With the development of science and technology, wind power technology has become quite mature, and larger and better-performing wind turbines have been developed and put into production and trial operation. However, since most wind turbines are installed in areas with harsh environments, they are prone to failure. If there is no timely fault warning, it will not only affect the service life and working efficiency of wind power equipment, but may even lead to major accidents such as wind turbine damage, causing irreparable losses.

[0003] The wind turbine tower is an important load-bearing structure for the wind rotor and nacelle. For large wind turbines, the height is usually more than 100 meters. However, during the operation of the wind turbine, the wind rotor will be subjected to wind forces of different loads, resulting in a certain displacement. The tower, as the only supporting structure for the blades, will be subjected to complex and changeable loads such as wind thrust and torque, forcing the nacelle on the top of the tower to deviate from the center position, causing the tower to tilt and deform. When the deformation is too large, it is easy to cause the wind rotor to hit the tower and the fatigue of the tower structure to increase, or the tower foundation to tilt, endangering the safe operation of the wind turbine.

[0004] In the prior art, the tower top displacement is usually obtained by the following two methods:

[0005] 1. Single antenna GPS positioning method:

[0006] A single-antenna GPS measuring station is installed in the tower nacelle, and a GPS base station is deployed on the ground to monitor the displacement of the tower top through differential positioning. This solution uses a single-antenna GPS positioning method. Since the measuring station is installed in the tower top nacelle, and the nacelle is not a completely regular body, the actual tower center position cannot be accurately found during the installation process. There is an error between the GPS installation point and the actual center point of the tower, and the measurement accuracy cannot meet the millimeter-level displacement measurement requirements of the wind turbine tower top.

[0007] 2. Acceleration integral measurement method:

[0008] Multiple acceleration sensors are installed at different heights inside the tower. The accelerations in the two horizontal directions of x and y are measured by multiple acceleration sensors, and the measured accelerations are integrated twice to measure the displacement of the tower top. There are problems such as the inability to accurately obtain the initial position, the large cumulative error of the integral operation and low accuracy, and there are construction difficulties in installing the acceleration sensors in layers inside the tower.

[0009] In summary, there is an urgent need for a dual-antenna positioning error correction method based on attitude sensing data to solve the problems existing in the prior art. Summary of the invention

[0010] The present invention aims to provide a dual-antenna positioning error correction method based on attitude sensing data to solve the problem of large measurement error of the existing wind turbine tower offset.

[0011] To achieve the above object, the present invention provides a dual-antenna positioning error correction method based on attitude sensing data, comprising the following steps:

[0012] Step 1: Install the main antenna A and the auxiliary antenna B on the nacelle at the top of the wind turbine tower, so that a triangle structure is formed between the rotation center point C of the nacelle, the main antenna A and the auxiliary antenna B; install an attitude sensor on the nacelle, and record the initial attitude sensor data when the wind turbine is not running;

[0013] Step 2: When the wind rotor is stopped, the wind turbine nacelle is controlled to rotate so that the wind turbine nacelle rotates n times along the circumference of the tower at a fixed angle β, where n is a positive even number and β×n=360°, and the initial coordinates of the rotation center of the nacelle are obtained through the position coordinates of the main antenna A and the auxiliary antenna B;

[0014] Step 3: During the operation of the wind turbine, several sets of data are collected, and the horizontal offset of the rotation center of the nacelle is obtained through the position changes of the main antenna A and the auxiliary antenna B; at the same time, the horizontal offset of the wind turbine tower is obtained through the attitude sensor;

[0015] Step 4: Compare the horizontal offset of the nacelle rotation center obtained in step 3 with the horizontal offset of the tower. When the difference between the two is greater than the set correction threshold, use the horizontal offset of the wind turbine tower obtained by the attitude sensor to replace the horizontal offset of the nacelle rotation center.

[0016] Preferably, in step 1, the main antenna A and the auxiliary antenna B are both Beidou antennas, which cooperate with the Beidou reference station on the ground to collect Beidou measurement data; the initial attitude sensing data includes the initial inclination angle α 0 .

[0017] Preferably, in step 2, the initial coordinates of the rotation center of the cabin are Obtained by expression 1):

[0018]

[0019] Among them, 1≤i≤n, and are respectively the coordinate value of the main antenna A at the i-th rotation and the coordinate value of the main antenna A at the i+n / 2-th rotation which is symmetrical thereto;

[0020] and They are respectively the coordinate values ​​of the sub-antenna B at the i-th rotation and the coordinate values ​​of the sub-antenna B at the i+n / 2-th rotation which is symmetrical thereto.

[0021] Preferably, in step 3, the horizontal offset L of the cabin rotation center is obtained by changing the positions of the main antenna A and the auxiliary antenna B at time t. bd By expression 4), we can get:

[0022]

[0023] in, is the horizontal coordinate of the cabin rotation center at time t in the XOY plane, (x 0 ,y 0 ) is the horizontal coordinate of the initial coordinate of the cabin rotation center in the XOY plane.

[0024] Preferably, in step 3, the coordinates of the cabin rotation center at time t are Calculate by expressions 2) to 3):

[0025]

[0026]

[0027] in, is the three-dimensional coordinate of the phase center point of the main antenna A at time t in the navigation coordinate system; is the three-dimensional coordinates of the phase center point of the main antenna A and the rotation center point C of the cabin in the carrier coordinate system b; θ is the pitch angle of the cabin, is the azimuth angle of the cabin, γ is the roll angle of the cabin, and R is the angle with respect to θ, The matrix associated with γ.

[0028] Preferably, in step 3, the horizontal offset L of the wind turbine tower is obtained by the attitude sensor corresponding to time t. Z Calculate by expression 6):

[0029] L z =H*sin(α t -α 0 ) 6);

[0030] Among them, H is the tower height, α t It is the angle data measured by the attitude sensor at time t.

[0031] Preferably, in step 4, the horizontal offset L of the cabin rotation center corresponding to the same moment is bd and the horizontal offset L of the wind turbine towerZ As a set of simultaneous data, during the operation of the wind turbine, at least 7200 sets of sample data are collected and then the correction threshold is confirmed.

[0032] Preferably, a preliminary screening operation is performed before the correction threshold is confirmed in step 4: if there is L in the jth group of simultaneous data in the sample data, bdj >H / 75 or L Zj >H / 75, the data set is eliminated; among them, L bdj is the horizontal offset of the nacelle rotation center in the jth group of simultaneous data, L Zj is the horizontal offset of the wind turbine tower in the jth group of data at the same moment.

[0033] Preferably, the modified threshold Q in step 4 is calculated by expression 7):

[0034] Q = σ * ω * η 7);

[0035] Where σ is the correlation coefficient, which is calculated by expression 8):

[0036]

[0037] Among them, m is the number of data groups retained at the same time after the sample data is initially screened, L bdk is the horizontal offset of the cabin rotation center in the kth group of simultaneous data among the m groups of simultaneous data retained, L Zk is the horizontal offset of the wind turbine tower in the kth group of simultaneous data among the m groups of simultaneous data retained;

[0038] ω is the reliability coefficient, which is calculated by expression 9):

[0039]

[0040] Among them, Ratio is the residual ratio of the ambiguity fixed suboptimal result and the optimal result of Beidou data;

[0041] η is the correction rate coefficient, and its value range is 0.15562~0.15645.

[0042] Preferably, in step 4, after confirming the correction threshold Q, the pth group of simultaneous data obtained during the monitoring process is corrected in real time. bdp -L Zp |>Q, the horizontal offset of the wind turbine tower obtained by the attitude sensor is used to replace the horizontal offset of the nacelle rotation center; where L bdp is the horizontal offset of the cabin rotation center in the pth group of simultaneous data, L Zp is the horizontal offset of the wind turbine tower in the pth group of data at the same moment.

[0043] The application of the technical solution of the present invention has the following beneficial effects:

[0044] (1) In the present invention, by arranging dual antennas on the top of the cabin, the main antenna, the auxiliary antenna and the cabin rotation center point are distributed in a triangular structure, which can conveniently calculate the coordinates of the cabin rotation center point and reduce the measurement error caused by the deviation between the antenna installation position and the cabin rotation center point.

[0045] (2) In the present invention, positioning monitoring is performed through the main and auxiliary antennas, and monitoring is performed through the attitude sensor at the same time, which can realize the verification between different types of monitoring data, thereby improving the accuracy of the horizontal offset finally obtained.

[0046] (3) In the present invention, the cabin is manually controlled to rotate at a fixed angle along the circumference of the tower. The wind turbine rotor is in a stopped state, and the blades are not affected by wind force, which will not cause the tower to deflect. It is more convenient to determine the initial coordinates of the cabin rotation center through dual antennas. The initial coordinate values ​​of the cabin rotation center are calculated by multiple pairs of symmetrical coordinate values. The calculation is simple and reliable.

[0047] (4) In the present invention, by comparing the horizontal offset of the cabin rotation center obtained by Beidou monitoring data with the horizontal offset of the tower obtained by the attitude sensor, when the difference between the two is greater than the set correction threshold, the horizontal offset of the wind turbine tower obtained by the attitude sensor is used to replace the horizontal offset of the cabin rotation center for correction. This can avoid the abnormal data mutation that occurs when the high-frequency differential decomposition of the Beidou dual-antenna receiver is uncertain, and is conducive to reflecting the actual tilt state of the wind turbine tower.

[0048] (5) In the present invention, positioning error correction is performed after at least 7200 sets of data are collected. When the sample size is greater than 7200 sets, the collected data is sufficient to include the experimental demand for abnormal Beidou data, and at the same time, it is not necessary to spend too much time on data initialization.

[0049] (6) In the present invention, before performing substitution correction, the sample data is first screened to eliminate obviously abnormal measurement data, which can reduce the amount of calculation in the substitution correction process.

[0050] (7) In the present invention, the correlation coefficient σ is introduced in the process of confirming the correction threshold, which is used to characterize the degree of deviation between the Beidou measurement data and the attitude meter measurement data under normal data conditions; the reliability coefficient ω is introduced to associate the reliability factor of the Beidou data itself; the correction rate coefficient η is introduced to ensure that under any circumstances, the correction rate of the Beidou data using this method can always achieve the optimal effect; through the association of these three comprehensive coefficients, the elimination of abnormal mutation data is more accurate, and the wind turbine swing data is closer to the actual swing trajectory of the wind turbine operation.

[0051] In addition to the above-described objects, features and advantages, the present invention has other objects, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0053] Figure 1 is a structural schematic diagram of a fan in an embodiment of the present application;

[0054] Figure 2 It is a schematic diagram of obtaining the initial coordinates of the rotation center of the cabin in step 2 of the embodiment of the present application;

[0055] Figure 3 is a schematic diagram of the position change of the rotation center of the nacelle in the XOY plane during the operation of the wind turbine in an embodiment of the present application;

[0056] Figure 4 This is a schematic diagram of the principle of obtaining the horizontal offset of the wind turbine tower through the attitude sensor in an embodiment of the present application. DETAILED DESCRIPTION

[0057] The embodiments of the present invention are described in detail below with reference to the accompanying drawings, but the present invention can be implemented in many different ways as defined and covered by the claims.

[0058] Example:

[0059] See also Figures 1 to 4 , a dual-antenna positioning error correction method based on attitude sensing data, this embodiment is applied to the horizontal offset monitoring and error correction of the tower in the wind turbine generator set.

[0060] The wind turbine generator set in this embodiment is as follows Figure 1 As shown, it includes a tower arranged on a foundation. For a large wind turbine, the tower length can usually reach more than 100 meters. The nacelle is rotatably arranged on the top of the tower and can rotate 360° along the circumferential direction of the tower to find the windward direction and improve the efficiency of wind power generation. The rotation center of the nacelle is located on the center line of the nacelle rotation axis. The rotation axis of the wind wheel is coaxially rotated with the nacelle.

[0061] A dual-antenna positioning error correction method based on attitude sensing data comprises the following steps:

[0062] Step 1: Install the main antenna A and the auxiliary antenna B on the nacelle at the top of the wind turbine tower, so that a triangular structure is formed between the nacelle rotation center point C, the main antenna A and the auxiliary antenna B; and set tilt sensors at the relative positions of the main antenna A, the auxiliary antenna B and the center point of the tower, and the setting method of the tilt sensor is performed in accordance with the setting method in patent document CN114251239A.

[0063] The main antenna A and the auxiliary antenna B can select compatible antennas such as GNSS antennas, or can select antennas such as GPS antennas and Beidou antennas. In this embodiment, the main antenna A and the auxiliary antenna B are both Beidou antennas, which cooperate with the Beidou base station on the ground to realize the collection of Beidou measurement data on the top of the cabin; by using dual antennas to position and monitor the cabin, the monitoring accuracy can be improved and the positioning error caused by single antenna monitoring can be avoided.

[0064] Install an attitude sensor on the nacelle and record the initial attitude sensor data when the wind turbine is not running. The initial attitude sensor data includes the initial inclination angle α 0 .

[0065] Step 2: When the wind rotor is stopped, the wind turbine nacelle is controlled to rotate, so that the wind turbine nacelle rotates n times along the circumferential direction of the tower at a fixed angle β, where n is a positive even number, and β×n=360°, and n / 2 pairs of symmetrical measurement coordinates can be obtained. The initial coordinates of the rotation center of the nacelle are obtained through the position coordinates of the main antenna A and the auxiliary antenna B;

[0066] By manually controlling the nacelle to rotate along the circumferential direction of the tower, when the wind turbine rotor is in a stopped state, the blades are not affected by the wind force and will not cause the tower to deflect. In this embodiment, the fixed angle of rotation of the wind turbine nacelle is 45°, and the number of rotations is 8 times, and 4 sets of symmetrically measured three-dimensional coordinate values ​​can be obtained, such as Figure 2 As shown, A 1 , B 1 With A 5 , B 5 is a pair of symmetrically measured three-dimensional coordinate values, A 2 , B 2 With A 6 , B 6 is a pair of symmetrically measured three-dimensional coordinate values. Similarly, the cabin rotation center C 0 The initial coordinates of Obtained by expression 1):

[0067]

[0068] Among them, 1≤i≤n, and are respectively the coordinate value of the main antenna A at the i-th rotation and the coordinate value of the main antenna A at the i+n / 2-th rotation which is symmetrical thereto;

[0069] and They are respectively the coordinate values ​​of the sub-antenna B at the i-th rotation and the coordinate values ​​of the sub-antenna B at the i+n / 2-th rotation which is symmetrical thereto.

[0070] The initial coordinate values ​​of the rotation center of the cabin are calculated by using multiple pairs of symmetric coordinate values. The calculation is simple and reliable. In this embodiment, the value of n is 8.

[0071] Step 3: During the operation of the wind turbine, several sets of data are collected, and the horizontal offset of the rotation center of the nacelle is obtained through the position changes of the main antenna A and the auxiliary antenna B; at the same time, the horizontal offset of the wind turbine tower is obtained through the attitude sensor;

[0072] During the acquisition process, the Beidou measurement data is collected by the Beidou receiver at a sampling frequency of 1 time / s, and at the same time, the real-time solution is performed at a frequency of 1Hz at the front end of the receiver to record the coordinate values ​​of the main antenna A and the secondary antenna B;

[0073] During the operation of the wind turbine, the rotation center of the nacelle will be offset by the wind rotor. At different times, the position of the rotation center of the nacelle in the XOY plane is different, such as Figure 3 As shown, it shows that during operation C 1 , C 2 and C 3 The positions of the three nacelle rotation centers after being offset in the horizontal plane (i.e., in the XOY plane).

[0074] Coordinates of the cabin rotation center at time t Calculate by expressions 2) to 3):

[0075]

[0076]

[0077] in, is the three-dimensional coordinate of the phase center point of the main antenna A at time t in the navigation coordinate system; is the three-dimensional coordinates of the phase center point of the main antenna A and the rotation center point C of the cabin in the carrier coordinate system b; θ is the pitch angle of the cabin, is the azimuth angle of the cabin, γ is the roll angle of the cabin, and R is the angle with respect to θ, The matrix associated with γ.

[0078] The horizontal offset L of the cabin rotation center is obtained by the position change of the main antenna A and the auxiliary antenna B at time t bd By expression 4), we can get:

[0079]

[0080] in, is the horizontal coordinate of the cabin rotation center at time t in the XOY plane, (x 0 ,y 0 ) is the horizontal coordinate of the initial coordinate of the cabin rotation center in the XOY plane.

[0081] See also Figure 4 When the horizontal offset of the wind turbine tower is obtained by the attitude sensor, the horizontal offset of the wind turbine tower L Z It can be calculated by expression 5):

[0082] L Z =H t *sin(α t -α 0 ) 5);

[0083] Among them, H t is the straight length of the tower after deformation, α 0 is the initial inclination angle in the initial attitude sensor data, α t is the angle data measured by the attitude sensor at time t; when the tower displacement is less than the warning value, the straight line length of the tower after deformation is approximately the tower height, that is, H t =H, then the horizontal offset of the wind turbine tower is L Z Calculate by expression 6):

[0084] L Z =H*sin(α t -α 0 ) 6);

[0085] Where H is the tower height.

[0086] Step 4: Compare the horizontal offset of the nacelle rotation center obtained in step 3 with the horizontal offset of the tower. When the difference between the two is greater than the set correction threshold, use the horizontal offset of the wind turbine tower obtained by the attitude sensor to replace the horizontal offset of the nacelle rotation center.

[0087] 4.1. Sample data extraction: Before real-time data correction, the correction threshold Q must be confirmed according to the monitoring data, and the horizontal offset L of the cabin rotation center corresponding to the same time must be bd and the horizontal offset L of the wind turbine tower Z As a set of simultaneous data, during the operation of the wind turbine, after two to three hours of monitoring, at least 7,200 sets of sample data are collected to confirm the correction threshold. When the sample size is greater than 7,200 sets, the collected data is sufficient to include the experimental requirements of abnormal Beidou data, and at the same time, it does not take too much time to initialize the data.

[0088] 4.2. Preliminary screening: Preliminary screening of N groups of sample data. If there is L in the jth group of simultaneous data bdj >H / 75 or L Zj >H / 75, the data set is eliminated; among them, L bdj is the horizontal offset of the nacelle rotation center in the jth group of simultaneous data, L Zj is the horizontal offset of the wind turbine tower in the jth group of data at the same moment.

[0089] According to the GB 50135-2019 High-rise Structure Design Standard, the horizontal displacement angle limit of free-standing tower steel structure is That is, Δu≤H / 75, where Δu is the horizontal displacement and H is the height of the tower steel structure; combined with the wind turbine tower structure, the maximum allowable distance of the tower offset center position C (i.e., the nacelle rotation center) in normal operation is H / 75, and the maximum allowable value is generally much larger than the warning value set during deformation monitoring.

[0090] 4.3. Calculation of modified threshold value: After completing the initial screening, m groups of simultaneous data are retained, and the modified threshold value Q is calculated by expression 7):

[0091] Q = σ * ω * η 7);

[0092] Wherein, σ is the correlation coefficient, which is used to characterize the degree of deviation between Beidou measurement data and attitude instrument measurement data under normal data conditions, and is calculated by expression 8):

[0093]

[0094] Among them, m is the number of data groups retained at the same time after the sample data is initially screened, L bdk is the horizontal offset of the cabin rotation center in the kth group of simultaneous data among the m groups of simultaneous data retained, L Zk is the horizontal offset of the wind turbine tower in the kth group of simultaneous data among the m groups of simultaneous data retained;

[0095] ω is the reliability coefficient, which is calculated by expression 9):

[0096]

[0097] Among them, Ratio is the residual ratio of the ambiguity fixed suboptimal result and the optimal result of Beidou data, that is, the reliability factor of Beidou data, where 3.0≤Ratio≤50, and the larger the value of Ratio is, the higher the reliability of Beidou data. When the selected Ratio is less than 3, it means that the data reliability is too low, and the Beidou receiver does not output the solution result. According to experimental data, the Ratio value of normal Beidou measurement data is usually around 20, and 50 is taken as the upper limit, that is, when the Ratio value is greater than 50, it is still calculated as 50. The purpose of introducing the reliability coefficient ω is to associate the reliability factor of the Beidou data itself, that is, the higher the reliability of the Beidou data, the less abnormal data needs to be eliminated, and the lower the reliability, the more abnormal data needs to be eliminated;

[0098] η is the correction rate coefficient, and its value range is 0.15562~0.15645. The introduction of this parameter is to ensure that under any circumstances, the correction rate of Beidou data using this method can always achieve the optimal effect.

[0099] Through experimental verification, when η takes different values, the correction rate of Beidou abnormal mutation data after initial screening is shown in the following table:

[0100] Table 1 Correction situation table corresponding to the correction rate coefficient value

[0101] Serial number η value Correction rate 1 0.15303 64.52％ 2 0.15460 88.87％ 3 0.15562 95.16％ 4 0.15575 96.77％ 5 0.15623 98.39％ 6 0.15631 96.13％ 7 0.15645 95.42％ 8 0.15767 87.10％ 9 0.16106 66.13％

[0102] It can be seen from Table 1 that when the value range of η is 0.15562-0.15645, the correction rate of abnormal mutation data can reach more than 95%, which can successfully correct the error of Beidou real-time positioning data and achieve the purpose of correcting the error of dual-antenna positioning data through attitude sensing data.

[0103] 4.4. Positioning data correction: During the monitoring process, the horizontal offset L of the cabin rotation center measured by the Beidou antenna bd and the horizontal offset L of the wind turbine tower measured by the attitude sensor Z The gap is relatively small. Since Beidou measurement data has higher accuracy, dual-antenna monitoring data is mainly used when monitoring the horizontal offset of the tower, supplemented by attitude sensing data.

[0104] However, when the Beidou receiver uses 1Hz high-frequency differential data to solve the distance of the tower's offset rotation center point in real time, there is a differential data interruption; at the same time, the tower top motor runs at a huge power, and the Beidou receiver runs in a strong electromagnetic environment. Under strong electromagnetic interference, data distortion may occur; considering the above two objective factors, the Beidou dual-antenna receiver will have abnormal data mutations when the high-frequency differential decomposition is not performed, which cannot reflect the actual tilt state of the wind turbine tower. The horizontal offset L of the wind turbine tower measured by the attitude sensor is required. ZThe horizontal offset L of the nacelle rotation center measured by BeiDou bd The abnormal mutation data in the .

[0105] For the pth group of simultaneous data (p is a positive integer) obtained after confirming the modified threshold Q, when |L bdp -L Zp |>Q (L bdp is the horizontal offset of the cabin rotation center in the pth group of simultaneous data, L Zp is the horizontal offset of the wind turbine tower in the pth group of data at the same time), and the horizontal offset L of the wind turbine tower obtained by the attitude sensor is used. Zp Horizontal offset L from the nacelle rotation center bdp Make an alternative correction.

[0106] Step 5: Determine whether to immediately execute the fan shutdown command based on the comparison between the corrected horizontal offset and the warning value.

[0107] L represents the corrected horizontal offset. When the value of L is greater than the warning value set during deformation monitoring, the wind turbine shutdown command is executed to prevent the tower from deforming too much and causing the wind wheel to hit the tower, increase the fatigue of the tower structure, or cause the tower foundation to tilt, endangering the safe operation of the wind turbine.

[0108] When the value of L is less than the warning value set during deformation monitoring, it means that the fan is operating normally and there is no safety risk.

[0109] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A dual-antenna positioning error correction method based on attitude sensing data, It is characterized in that The following steps are involved: Step 1: Install the main antenna A and the auxiliary antenna B on the nacelle at the top of the wind turbine tower, so that a triangle structure is formed between the rotation center point C of the nacelle, the main antenna A and the auxiliary antenna B; install an attitude sensor on the nacelle, and record the initial attitude sensor data when the wind turbine is not running; Step 2: When the wind rotor is stopped, the wind turbine nacelle is controlled to rotate so that the wind turbine nacelle rotates n times along the circumference of the tower at a fixed angle β, where n is a positive even number and β×n=360°, and the initial coordinates of the rotation center of the nacelle are obtained through the position coordinates of the main antenna A and the auxiliary antenna B; Step 3: During the operation of the wind turbine, several sets of data are collected, and the horizontal offset of the rotation center of the nacelle is obtained through the position changes of the main antenna A and the auxiliary antenna B; at the same time, the horizontal offset of the wind turbine tower is obtained through the attitude sensor; Step 4: Compare the horizontal offset of the nacelle rotation center obtained in step 3 with the horizontal offset of the tower. When the difference between the two is greater than the set correction threshold, use the horizontal offset of the wind turbine tower obtained by the attitude sensor to replace the horizontal offset of the nacelle rotation center.

2. A dual-antenna positioning error correction method based on attitude sensing data according to claim 1, It is characterized in that In the step 1, the main antenna A and the auxiliary antenna B are both Beidou antennas, which cooperate with the Beidou reference station on the ground to realize the collection of Beidou measurement data; the initial attitude sensing data includes the initial inclination angle α 0 .

3. A dual-antenna positioning error correction method based on attitude sensing data according to claim 1 or 2, It is characterized in that In step 2, the initial coordinates of the cabin rotation center By expression (1), we can obtain: Among them, 1≤i≤n, and are respectively the coordinate value of the main antenna A at the i-th rotation and the coordinate value of the main antenna A at the i+n / 2-th rotation which is symmetrical thereto; and They are respectively the coordinate values ​​of the sub-antenna B at the i-th rotation and the coordinate values ​​of the sub-antenna B at the i+n / 2-th rotation which is symmetrical thereto.

4. The dual-antenna positioning error correction method based on attitude sensing data according to claim 1, It is characterized in that In step 3, the horizontal offset L of the cabin rotation center is obtained by changing the positions of the main antenna A and the auxiliary antenna B at time t. bd By expression (4), we can obtain: in, is the horizontal coordinate of the cabin rotation center at time t in the XOY plane, (x 0 ,y 0 ) is the horizontal coordinate of the initial coordinate of the cabin rotation center in the XOY plane.

5. The dual-antenna positioning error correction method based on attitude sensing data according to claim 4, It is characterized in that In step 3, the coordinates of the cabin rotation center at time t Calculate by expressions (2) to (3): in, is the three-dimensional coordinate of the phase center point of the main antenna A at time t in the navigation coordinate system; is the three-dimensional coordinates of the phase center point of the main antenna A and the rotation center point C of the cabin in the carrier coordinate system b; θ is the pitch angle of the cabin, is the azimuth angle of the cabin, γ is the roll angle of the cabin, and R is the angle with respect to θ, The matrix associated with γ.

6. The dual-antenna positioning error correction method based on attitude sensing data according to claim 4, It is characterized in that In step 3, the horizontal offset L of the wind turbine tower is obtained by the attitude sensor at time t. Z Calculated by expression (6): L z =H*sin(α t -a 0 ) (6); Among them, H is the tower height, α t It is the angle data measured by the attitude sensor at time t.

7. The dual-antenna positioning error correction method based on attitude sensing data according to claim 6, It is characterized in that In step 4, the horizontal offset L of the cabin rotation center corresponding to the same time bd and the horizontal offset L of the wind turbine tower Z As a set of simultaneous data, during the operation of the wind turbine, at least 7200 sets of sample data are collected and then the correction threshold is confirmed.

8. The dual-antenna positioning error correction method based on attitude sensing data according to claim 7, It is characterized in that Before confirming the correction threshold in the fourth step, a preliminary screening operation is performed: If there is an L bdj > H / 75 or an L Zj > H / 75 in the data of the j-th group at the same time in the sample data, the data of this group is excluded; where L bdj is the horizontal offset of the center of rotation of the nacelle in the data of the j-th group at the same time, and L Zj is the horizontal offset of the wind turbine tower barrel in the data of the j-th group at the same time.

9. The dual-antenna positioning error correction method based on attitude sensing data according to claim 8, It is characterized in that The modified threshold Q in step 4 is calculated by expression (7): Q = σ*ω*η (7); Where σ is the correlation coefficient, which is calculated by expression (8): Among them, m is the number of data groups retained at the same time after the sample data is initially screened, L bdk is the horizontal offset of the cabin rotation center in the kth group of simultaneous data among the m groups of simultaneous data, L Zk is the horizontal offset of the wind turbine tower in the kth group of simultaneous data among the m groups of simultaneous data retained; ω is the reliability coefficient, which is calculated by expression (9): Among them, Ratio is the residual ratio of the ambiguity fixed suboptimal result and the optimal result of Beidou data; η is the correction rate coefficient, and its value range is 0.15562~0.15645.

10. The dual-antenna positioning error correction method based on attitude sensing data according to claim 9, It is characterized in that In the step 4, after confirming the correction threshold Q, the pth group of simultaneous data obtained during the monitoring process is corrected in real time. bdp -L Zp |>Q, the horizontal offset of the wind turbine tower obtained by the attitude sensor is used to replace the horizontal offset of the nacelle rotation center; where L bdp is the horizontal offset of the cabin rotation center in the pth group of simultaneous data, L Zp is the horizontal offset of the wind turbine tower in the pth group of data at the same moment.

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