A control method for improving the stability of the mold gap of a wind power blade

Abstract

This invention provides a method for controlling the stability of the mold closing clearance of wind turbine blades. The method includes: using a web positioning reference, monitoring unit, and adjustment structure arranged outside the mold, precisely positioning the web to a preset position in three-dimensional space to ensure consistent posture before mold insertion; using a lifting and bonding fixture to lift the web into the mold, while simultaneously collecting the web's position information and storing it in a database; calculating and predicting the mold closing clearance; and adaptively adjusting the adhesive layer thickness in areas with out-of-tolerance conditions. This invention achieves precise pre-compensation for the mold closing clearance through precise external positioning and spatial coordinate fusion calculation, effectively improving the clearance consistency in batch production. This invention ensures consistent web insertion posture through precise external positioning, achieving pre-compensation and adjustment of the mold closing clearance, effectively improving the stability of the mold closing clearance for batch blades.

Description

Technical Field

[0001] This invention relates to the field of wind turbine blade manufacturing technology, and more specifically, to a method for controlling the stability of the mold clearance of wind turbine blades. Background Technology

[0002] Wind turbine blades are assembled from a PS shell (frontal pressure side), an SS shell (leeward suction side), and an internal web. The mainstream manufacturing process involves first bonding the lower flange of the web to the main beam inside one half of the shell, then hoisting the other half of the shell downwards and fastening it in place, thus bonding the upper flange of the web to the corresponding inner wall of the shell. The vertical distance between the upper flange of the web and the inner wall of the shell is the mold closing gap, which is typically required to be controlled between 3mm and 10mm within the acceptable range. The mold closing gap directly determines the final thickness of the structural adhesive layer: too small a gap can easily lead to top mold interference and localized adhesive defects, while too large a gap results in insufficient adhesive layer thickness. Both situations significantly weaken the structural strength of the blade's bonding area and reduce the overall fatigue life of the turbine. As wind turbine blades continue to develop towards larger and lighter sizes, the overall length of the web has increased significantly, resulting in a significant decrease in the rigidity of the web itself. Due to multiple factors, such as tooling deflection during web hoisting and mold insertion, lack of a reproducible unified high-precision benchmark for the half-shell mold itself, and cumulative deformation of hoisting and bonding tooling during long-term use, the fluctuation range of the mold closing gap along the blade span continues to expand, and the difficulty of controlling the gap stability increases exponentially.

[0003] Patent application CN202010338741.6 discloses a method for testing the mold fitting compatibility of wind turbine blades. It employs a PDCA cycle to control the frequency of trial mold fittings, relies on clay sampling to measure gaps, and relies solely on padding and core-adjusting materials for post-construction repair of defects, posing a risk of missing the top mold. Patent application CN202210705967.4 discloses a wind turbine blade mold fitting gap scanning and measuring device and method. It uses guide rails on both sides of the mold, equipped with dual laser probes to scan the PS and SS shells respectively, and calculates the single-point mold fitting gap in real time based on the fixed flange distance. It also issues an audible and visual alarm when the gap is abnormal, thus eliminating the need for manual clay application to some extent. However, the testing in this method is all carried out after the web has been bonded to the shell. Problems such as web misalignment and bending deformation cannot be identified and corrected before mold insertion, requiring post-construction repairs after the web posture has solidified. Essentially, this solution still falls under the post-construction control model of "attaching first, testing later, and repairing after testing," failing to address the fundamental problem of inaccurate web plate positioning at its source.

[0004] Therefore, there is an urgent need for a method to stabilize the gap between the molds of wind turbine blades, which can achieve source location, global detection, and pre-mold repair, so as to improve the stability of the gap between the molds of the blades. Summary of the Invention

[0005] In view of this, the present invention aims to propose a control method to improve the stability of the gap between the mold and the blade of a wind turbine, so as to solve the problem that the existing technology can only carry out gap detection after the web is bonded into the mold, and cannot eliminate the tooling deformation and the deviation of the web itself in advance.

[0006] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0007] This invention provides a method for controlling the stability of the mold closing gap of wind turbine blades, comprising the following steps:

[0008] Step S1: Precise localization of the web plate in one step:

[0009] By using pre-arranged web plate positioning references, web plate positioning monitoring units, and web plate positioning adjustment structures on the outside of the mold, the web plate is positioned to a preset position in three-dimensional space to ensure that the web plate has a consistent posture before entering the mold.

[0010] Step S2: Acquisition of web plate position information:

[0011] The location information of the web plate was collected using hoisting and bonding fixtures and stored in the database;

[0012] Step S3: Gap Calculation and Prediction:

[0013] When bonding the first web plate, the reference mold closing gap Z1 of the first web plate is obtained by actual measurement; when bonding the nth (n>1) web plate, the reference mold closing gap Z' of the previous web plate is retrieved from the database, and the predicted mold closing gap Z of this web plate is calculated.

[0014] Step S4: Gap compensation:

[0015] Based on the calculation results of step S3, the thickness of the adhesive layer corresponding to the out-of-tolerance area of ​​the web is adaptively adjusted so that the adjusted mold closing gap falls within the qualified range.

[0016] It should be noted that, in this invention, the reference mold closing gap Z' is the gap when the previous web plate is finally molded or the predicted mold closing gap.

[0017] Furthermore, in step S1, the web plate positioning reference is one or both of a physical positioning reference and a virtual positioning reference; the web plate positioning monitoring unit is one or both of a contact monitoring device and a non-contact monitoring device.

[0018] Furthermore, in step S1, the web is first coarsely positioned using a physical positioning datum, and then finely positioned using a virtual positioning datum.

[0019] Furthermore, in step S1, the web plate positioning reference includes a first direction positioning reference, a second direction positioning reference, and a third direction positioning reference; the web plate positioning monitoring unit is correspondingly provided with a first direction positioning monitoring unit, a second direction positioning monitoring unit, and a third direction positioning monitoring unit; the web plate positioning adjustment structure includes a first direction positioning adjustment structure, a second direction positioning adjustment structure, and a third direction positioning adjustment structure.

[0020] Furthermore, in step S1, the positioning method in the first direction is as follows:

[0021] A first-direction feature point is pre-formed on the web plate. A limiting area formed by dual-beam laser projection is used as a virtual positioning reference for the first direction. The position of the first-direction feature point relative to the limiting area is monitored by a first-direction positioning monitoring unit. The first-direction feature point is adjusted to the limiting area by a traveling vehicle to complete the first-direction positioning.

[0022] Furthermore, in step S1, the positioning method in the second direction is as follows:

[0023] A square steel bar is set on the left or right side of the web as a second directional positioning reference, and at least two laser rangefinders with known spacing are used as second directional positioning monitoring units to measure the distance from the web to the square steel bar.

[0024] A second-direction positioning adjustment structure driven by a hydraulic cylinder is set on the other side of the web plate to push the web plate to move in the second-direction positioning reference direction until the measurement value fed back by the laser range sensor reaches the preset positioning threshold, thus completing the second-direction positioning.

[0025] The torsion angle of the web in the second direction is calculated from the difference between the measurements of the two laser rangefinders.

[0026] Furthermore, in step S1, the positioning method in the third direction is as follows:

[0027] A third-party positioning and adjustment structure is set at the bottom of the web so that the web falls into the upper plane of the third-party positioning and adjustment structure;

[0028] At least two laser rangefinders are placed below the bonding surface of the web plate. The distance from the laser rangefinder itself to the bonding surface of the web plate is measured. The third-party positioning adjustment structure is driven by a hydraulic cylinder to complete the lifting and lowering adjustment until the difference between the measured value and the theoretical value of the laser rangefinder is within the preset range, thus completing the third-party positioning.

[0029] Furthermore, in step S2, before the web plate is lifted into the mold using the lifting and bonding fixture, the relative position information P1 of the bonding surface on the web plate is collected based on the lifting and bonding fixture; the deformation compensation information P2 of the lifting and bonding fixture is collected based on the calibration device; P1 and P2 are superimposed and calculated to obtain the absolute spatial position information P3 of the bonding surface on the web plate under the external global reference, and the P3 obtained in this calculation is stored in the database.

[0030] It should be noted that the specific detection method for the relative position information P1, deformation compensation information P2, and absolute spatial position information P3 in step S2 includes the following steps:

[0031] Step S21: Obtain the relative position information P1 of the bonding surfaces on the web.

[0032] A local coordinate system is established based on the hoisting and bonding fixture, and the relative position information P1 of the bonding surface on the web relative to the local coordinate system is obtained.

[0033] Step S22: Obtain the deformation compensation information P2 of the hoisting and bonding fixture.

[0034] A global coordinate system is established based on the external structure with known coordinates, and the deformation compensation information P2 of the hoisting and bonding fixture is obtained.

[0035] Step S23: Reconstruct the absolute spatial position information P3 of the bonding surface on the web.

[0036] The relative position information P1 and the deformation compensation information P2 are fused together in spatial coordinates to eliminate the deformation error of the hoisting and bonding fixture, and to reconstruct the absolute spatial position information P3 of the bonding surface on the web in the global coordinate system.

[0037] It should be noted that in step S23 of this invention, the deformation compensation information P2 of the lifting and bonding fixture refers to: the elastic deformation data generated by the lifting and bonding fixture after adsorbing the web due to its own weight and the contact constraint of the web. This data is used to correct the reference error in subsequent measurements to eliminate the influence of fixture deformation on positioning accuracy; and the spatial homogeneous transformation matrix T from the local coordinate system to the global coordinate system is constructed based on the deformation compensation information P2. match As shown in Equation 1 below:

[0038] Formula 1;

[0039] Where R is a 3×3 spatial rotation correction matrix, used to compensate for the spatial distortion and tilt attitude deviation of the tooling; t is a 3×1 spatial translation correction vector, used to compensate for the overall drift and gravitational sinking deflection of the tooling. Using this matrix, spatial coordinate transformation and deformation error compensation are performed on the local point cloud data P1 to reconstruct the absolute spatial position point cloud data P3=T. match ⋅P1. In the one-dimensional height measurement direction, the above spatial homogeneous transformation calculation can be directly simplified to algebraic subtraction P3=P1−P2.

[0040] This invention utilizes deformation correction parameters to compensate and correct the measured first relative position data, thereby eliminating the cumulative measurement error caused by the flexible deformation of the tooling and reconstructing the bonding surface on the web in the global coordinate system C. global The absolute spatial position below.

[0041] Furthermore, in step S21, a guide device is arranged on the lifting and bonding fixture, and a measuring device moving along the guide device continuously sweeps and measures the bonding surface on the web to obtain the relative position information P1.

[0042] Furthermore, the measuring device is one or more of a laser profile scanner, a lidar, and a laser rangefinder; the guiding device is a track and a track slider fixed on the crossbeam of the hoisting and bonding fixture frame; the measuring device slides and scans along the track, using the displacement value as the lateral coordinate and the vertical distance from the measuring device to the bonding surface on the web as the longitudinal height coordinate, to reconstruct the relative height point cloud data of the entire length dimension as the relative position information P1.

[0043] Furthermore, in step S22, deformation compensation information P2 is obtained using a calibration component. The calibration component includes a calibration device and a calibration object. One of the calibration device and the calibration object is placed on an external structure with known coordinates, and the other is placed on the hoisting and bonding fixture.

[0044] Furthermore, during the process of the measuring device acquiring the relative position information P1, the calibration device monitors the spatial position change of the calibration object in real time, and based on the coordinate offset of the calibration object in the global coordinate system, it deduces the displacement and attitude change data of the hoisting and bonding fixture as the deformation compensation information P2.

[0045] This invention uses a calibration object as a spatial reference object, employs a measuring device to monitor the coordinate changes of the spatial reference object, and obtains deformation compensation information P2 through inverse solving.

[0046] Furthermore, the calibration object is a plurality of reflective targets arranged at equal intervals on the crossbeam of the hoisting and bonding fixture frame, and the calibration device is a plurality of industrial cameras arranged parallel to the length direction of the web plate and fixed at a position on the outside of the mold.

[0047] Furthermore, step S23 also includes obtaining the absolute spatial position information P3' of the bonding surface on the web of the first reference blade, which satisfies: P3'=P1'-P2'; where P1' and P2' are the relative position information and deformation compensation information obtained when scanning the reference blade, respectively.

[0048] Furthermore, step S5, feedback adjustment, is also included:

[0049] Calculate the difference between the absolute spatial position information P3 of this web and the absolute spatial position information P3' of the previous web, denoted as ΔP=P3-P3'; for areas where the change of ΔP exceeds the preset range, perform feedback optimization and adjustment of equipment structure or web positioning parameters.

[0050] Furthermore, it also includes step S6, gap retesting:

[0051] After the lower bonding surface of the web plate is bonded to the inner side of the shell, the mold closing gap is re-measured. If the re-measured mold closing gap is within the preset range, the mold is closed normally. If the re-measured mold closing gap exceeds the preset range, the web plate is compensated for the gap until the re-measured mold closing gap reaches the preset range. The last measured re-measured mold closing gap is recorded as the reference mold closing gap Z' of this web plate.

[0052] Furthermore, during the web bonding and curing process, the mold closing gap is re-measured using the hoisting bonding fixture as a reference, and this is used as a re-measurement of the mold closing gap.

[0053] It should be noted that existing technologies rely on the clay method to obtain the actual measured gap; this invention, however, directly uses the mold closing gap measured by the tooling as the standard. This is because current main beams mostly adopt the pultrusion beam process, and their thickness direction variation is extremely small. Compared with the positioning and deformation errors of the web plate, these are negligible. Therefore, the height of the inner wall of the SS shell can be regarded as a constant reference, and the tooling measurement results have sufficient engineering accuracy.

[0054] Compared with existing technologies, the control method for improving the stability of the mold closing gap of wind turbine blades described in this invention has the following advantages:

[0055] (1) This invention pre-sets a positioning reference, a positioning monitoring unit, and a positioning adjustment structure outside the mold. In the first, second, and third directions, each web plate is locked to the same preset spatial position, ensuring the consistency of the web plate's posture before entering the mold. This eliminates the problem of web plate posture drift caused by the lack of a unified reference inside the mold and the distortion of data from manual retesting in traditional processes. At the same time, this invention uses a line laser scanner to continuously scan and measure along the guide rail to obtain continuous position information over the entire length of the web plate. This overcomes the risk of missed judgments in the sparse discrete sampling of the traditional clay method, enabling the measurement data to truly reflect the gap state at any position, providing a complete and reliable data foundation for subsequent gap prediction.

[0056] (2) The present invention completes the full-size gap prediction and adhesive layer thickness compensation adjustment before the web is bonded, so that the mold closing gap meets the qualified requirements before the web is bonded and cured. It realizes the active control mode of "test first and control later, pre-adjustment in advance", avoids the waste of time and mold occupation caused by repeated mold flipping and multiple repairs due to gap deviation, significantly shortens the production cycle and reduces manufacturing costs.

[0057] (3) This invention stores the absolute spatial position information P3 and the predicted gap Z of each blade in the database, so that subsequent blades can be iteratively calculated based on the measured or predicted data of the previous blade. This effectively eliminates the cumulative error caused by factors such as mold elastic deformation, slow temperature drift, and wear of positioning reference during the production process. With the feedback adjustment mechanism, the equipment structure or positioning parameters of the area where the ΔP change exceeds the preset range are continuously optimized, forming a complete control closed loop of "measurement → prediction → compensation → remeasurement → feedback", so that the mold gap control results have good consistency and repeatability. Attached Figure Description

[0058] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0059] Figure 1 This is a schematic diagram of the mold closing gap for wind turbine blades.

[0060] Figure 2 This is a schematic diagram showing the positioning of the web in the first direction;

[0061] Figure 3 This is a schematic diagram showing the positioning of the second and third directions of the web.

[0062] Figure 4 A schematic diagram of the overall structure of the positioning tooling frame;

[0063] Figure 5 This is a schematic diagram of the spatial location information of the bonding surface on the web.

[0064] Explanation of reference numerals in the attached figures:

[0065] 1. SS shell; 2. PS shell; 3. Web plate; 4. Mold closing clearance; 101. First direction; 102. Second direction; 103. Third direction; 5. Virtual positioning reference for the first direction; 501. Physical positioning reference for the first direction; 502. Positioning monitoring unit for the first direction; 503. Feature point for the first direction; 6. Positioning fixture; 601. Host computer; 602. Positioning monitoring unit for the third direction; 603. Positioning adjustment structure for the third direction; 604. Positioning monitoring unit for the second direction; 605. Positioning reference for the second direction; 606. Positioning adjustment structure for the second direction; 7. Lifting and bonding fixture; 701. Measuring device; 702. Guiding device; 8. Calibration device. Detailed Implementation

[0066] The present invention will be further described below with reference to specific embodiments. First, it should be noted that the data in the following experimental examples were obtained by the inventors through numerous experiments. Due to space limitations, only a portion of these data is shown in the specification, and those skilled in the art can understand and implement the present invention based on this data. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the contents of this invention, those skilled in the art can make various modifications or alterations to the invention, and these modifications or alterations also fall within the scope of protection of this application.

[0067] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0068] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0069] The existing industry-standard process for controlling the bonding gap of web plates mainly consists of four steps: web plate positioning, gap acquisition, gap repair, and gap re-measurement. The specific process is as follows: After the web plate is bonded to the inside of the shell, rough positioning is first achieved with the help of a tooling fixture, and then fine positioning is achieved by manual re-measurement and adjustment. The mold closing gap is controlled by limiting the displacement of the web plate in three directions. Then, modeling clay is placed in the bonding area. After the mold is closed and flipped, the thickness of the modeling clay after being compressed is manually measured to record the gap value. Based on the measurement results, the gaps that exceed the tolerance are repaired by grinding, adding material, etc., so that the gaps are within the acceptable range. The gap detection and repair operations are repeated until the gaps of the entire section meet the standard of 3mm ≤ gap ≤ 10mm.

[0070] This traditional process has three inherent and unavoidable defects: the precision positioning process has a large range of working conditions and no unified benchmark, and the data obtained by manual re-measurement is obviously distorted, so adjusting the web posture based on this data cannot play an effective corrective role; the clay sampling inspection is a sparse and discrete sampling method, and if there are problems such as local mold top-off or gap abrupt changes in areas where clay is not laid, the measurement data cannot reflect the true gap state; it is impossible to predict the mold closing gap distribution in advance, and can only rework after problems such as gaps being too large or too small occur, and each rework requires flipping the mold for re-verification, which is cumbersome and has low overall production efficiency.

[0071] It should be noted that, as Figure 1 As shown, in the following embodiments, the first direction 101 is along the blade spanwise direction, from the blade root to the blade tip; the second direction 102 is along the airfoil chord direction, from the leading edge to the trailing edge; the third direction 103 is along the blade height direction, i.e., the local thickness direction of the blade; the mold closing gap 4 refers to the vertical distance between the flange (upper bonding surface) on the web 3 and the inner wall of the shell (SS shell).

[0072] like Figures 2-3 As shown in the figure, this embodiment provides a method for controlling the stability of the mold closing gap of a wind turbine blade, including the following steps:

[0073] Step S1: Precision positioning of the web plate 3 in one step:

[0074] By using pre-arranged web plate positioning reference, web plate positioning monitoring unit and web plate positioning adjustment structure on the outside of the mold, the web plate 3 is positioned to the preset position in three-dimensional space to ensure that the web plate 3 has a consistent posture before entering the mold.

[0075] Step S2: Acquisition of web plate 3 position information:

[0076] The position information of the web plate 3 was collected and stored in the database using the hoisting and bonding fixture 7.

[0077] Step S3: Gap Calculation and Prediction:

[0078] When bonding the first web plate 3, the reference mold closing gap Z1 of the first web plate 3 is obtained by actual measurement; when bonding the nth (n>1) web plate 3, the reference mold closing gap Z' of the previous web plate 3 is retrieved from the database, and the predicted mold closing gap Z of this web plate 3 is calculated.

[0079] Step S4: Gap compensation:

[0080] Based on the calculation results of step S3, the thickness of the adhesive layer corresponding to the out-of-tolerance area of ​​the web 3 is adaptively adjusted so that the adjusted mold closing gap falls within the qualified range.

[0081] In a preferred embodiment, the specific positioning method for step S1 is as follows:

[0082] A web plate positioning reference, a web plate positioning monitoring device, and a web plate positioning adjustment device are set up on a pre-set tooling frame outside the mold. The three work together in a coordinated manner. The positioning monitoring device detects the distance between the web plate 3 and the corresponding positioning reference in real time. Then, the positioning adjustment mechanism continuously corrects the posture of the web plate 3. The measurement and adjustment are repeated until the difference between the measured distance and the theoretical distance is ≤D (D is the web plate positioning tolerance, preferably 1mm). This completes the measurement, adjustment, and re-measurement of the web plate 3 in all directions.

[0083] It should be noted that during the positioning process in S1 of this embodiment, the first direction 101 (blade spanwise / lengthwise direction) is used to constrain the front-to-back position of the web 3 from the blade root to the blade tip, preventing overall misalignment during hoisting and mold insertion, which could lead to gap deviations and misalignment with the design expectations. The second direction 102 (blade chordwise / widthwise direction) is used to constrain the left-to-right offset and torsional tilt around the length direction of the web 3, avoiding uneven left-to-right gaps caused by inconsistent upper flange heights on both sides of the web 3. The third direction 103 (blade thicknesswise / heightwise direction) uses multi-point support to adjust the web 3 as a whole to a height shape consistent with the theoretical spatial curve of the design model, eliminating spanwise deflection deformation caused by the weight of the large web 3. The three directions work together to ensure that the web 3 is in a qualified state of "correct position, upright posture, and smooth shape" before being inserted into the mold. The absence of any direction will lead to distortion of the spatial orientation of the web 3, and the subsequent measurement and control of the mold closing gap will lose its reliable basis.

[0084] In this embodiment, a web plate positioning reference, a web plate positioning monitoring device, and a web plate positioning adjustment device are deployed on a pre-set tooling frame outside the mold. This locks each web plate 3 to the same pre-set spatial position, ensuring a high degree of consistency in the pre-mold orientation of the web plate 3 in three directions. The absolute correctness of this pre-set position is determined by existing conventional measurement methods, which will not be elaborated upon here. The core contribution of this step lies in establishing a reproducible positioning reference outside the mold, independent of various interference factors in the production environment, so that each web plate 3 is constrained to the same spatial orientation before mold closing.

[0085] In this embodiment, as Figure 4As shown, a positioning fixture 6 is used to position and adjust the posture of the web plate 3 in the second direction 102 and the third direction 103. The positioning fixture 6 integrates a third-direction positioning monitoring unit 602, a third-direction positioning adjustment structure 603, a second-direction positioning monitoring unit 604, a second-direction positioning reference 605, and a second-direction positioning adjustment structure 606. The third-direction positioning adjustment structure 603 is a hydraulically driven support component used to support the web plate 3 and drive it to move up and down along the third direction 103, achieving coarse positioning and precise adjustment of the web plate 3's height. The second-direction positioning reference 605 is a rigid limiting component that cooperates with the second-direction positioning adjustment structure 606 to laterally clamp and push the web plate 3, achieving translational positioning of the web plate 3 along the second direction 102. The second-direction positioning reference 605 provides a positioning reference for the web plate 3 in the second direction, and the second-direction positioning adjustment structure 606 provides driving force for the web plate 3 in the second direction. The third-direction positioning monitoring unit 602 and the second-direction positioning monitoring unit 604 are sensors arranged at corresponding workstations, used to collect the position data of the web plate 3 in real time and feed it back to the control system to assist in completing the high-precision positioning of the web plate 3.

[0086] It should be noted that this embodiment does not limit the shape of the positioning fixture 6 or the specific structure of its support. Any structural form that can achieve the above-mentioned coarse positioning, sensing detection and multi-directional adjustment functions is within the protection scope of this solution.

[0087] In step S2 of this embodiment, when the web plate 3 is lifted into the mold using the lifting and bonding fixture 7, the relative position information P1 of the bonding surface on the web plate 3 is collected based on the lifting and bonding fixture 7; the deformation compensation information P2 of the lifting and bonding fixture 7 is collected based on the calibration device 8; P1 and P2 are superimposed and calculated to obtain the absolute spatial position information P3 of the bonding surface on the web plate 3 under the external global reference, and the P3 obtained in this calculation is stored in the database.

[0088] It should be noted that after the measurement and gap compensation are completed, the web plate 3 is lifted into the mold using the lifting and bonding fixture 7. When the web plate 3 falls to the preset height, the lifting and bonding fixture 7 cooperates with the preset docking part (including but not limited to positioning pins, positioning grooves or flange stops) on the mold. The docking part restricts the spatial position and posture of the lifting and bonding fixture 7, thereby indirectly locking the position and posture of the web plate 3, so that it is consistent with the first precise positioning posture established on the positioning fixture 6, and avoids additional errors introduced by the lifting disturbance.

[0089] Example 1

[0090] A control method for improving the stability of the mold closing gap of wind turbine blades includes the following steps: Step S1: Precision positioning of web 3 in one step

[0091] The web plate 3 is precisely positioned outside the mold based on the preset standard coordinates. The specific operation is as follows: A tooling frame is independently built on the outside of the PS shell 2 and SS shell 1 forming mold, including a complete set of positioning references, positioning monitoring equipment and positioning adjustment mechanism in the first, second and third directions. The three dimensions are simultaneously calibrated before the web plate 3 is assembled to the PS shell 2. In this embodiment, the web plate positioning tolerance D is preferably taken as 1mm.

[0092] (1) First direction 101 calibration

[0093] The first direction physical positioning reference 501 is a rigid retaining wall fixed to the ground and distributed on the front and rear sides of the blade, serving as a coarse positioning limiter for the web plate 3; the first direction virtual positioning reference 5 is a standard limiting area formed by dual-beam laser projection; the first direction positioning monitoring unit 502 is an industrial camera, whose lens is aimed at the preset first direction feature point 503 of the web plate 3; the web plate first direction positioning adjustment device is a crane.

[0094] During operation, the web plate 3 is first pushed along the first direction 101, so that the end of the web plate 3 abuts against the first direction physical positioning reference 501, completing the rough spanwise positioning. After the rough positioning is completed, the first direction virtual positioning reference 5 is activated, which forms a standard positioning area through dual-beam laser projection. The industrial camera acquires images formed by the first direction feature points 503 in real time and transmits them to the host computer 601. The host computer 601 magnifies and displays the relative offset between the first direction feature points 503 and the standard positioning area. The operator manipulates the crane to fine-tune the position of the web plate 3 and continuously observes the screen until the first direction feature points 503 are completely aligned with the standard positioning area, and the difference between the actual position and the theoretical position of the feature points is ≤1mm. The first direction positioning is then completed.

[0095] (2) Second direction 102 calibration

[0096] The second direction positioning reference 605 is a square steel perpendicular to the plane formed by the first direction and the second direction, serving as a positioning limiter for the web plate 3; the second direction positioning monitoring unit 604 consists of multiple sets of laser rangefinders; the second direction positioning adjustment structure 606 consists of a hydraulic push rod and a side plate that cooperates with it.

[0097] During operation, the web plate 3 is first pushed laterally so that the side of the web plate 3 is in contact with the second direction positioning reference 605, completing the coarse chordal limit. After the coarse positioning is completed, the laser range sensor collects the distance data between the side of the web plate 3 and the reference in real time and transmits it to the host computer 601. The host computer 601 calculates the tilt angle of the web plate 3 by combining multiple sets of distance measurement values. The operator manipulates the hydraulic push rod to push the web plate 3 slightly and continuously fine-tunes the lateral position until the web plate 3 is centered along the second direction 102 and the tilt deviation meets the requirements. The sensor outputs the positioning signal, and the second direction positioning is completed.

[0098] (3) Third-party calibration of 103

[0099] The third-party positioning adjustment structure 603 is a platform located on the lower side of the web plate 3. Its upper plane is a physical positioning reference, and the structure also has a lifting and adjustment function, serving as a positioning support for the web plate 3. The third-party positioning monitoring unit 602 is a laser rangefinder sensor set on the lower side of the third-party positioning adjustment structure 603 and arranged vertically, with its front plane serving as a virtual positioning reference.

[0100] During operation, the web plate 3 is placed stably on the upper support plane of the third-direction positioning and adjustment structure 603 to complete the rough limiting in the thickness direction. After the rough positioning is completed, the third-direction positioning monitoring unit 602 measures the difference between the upper flange of the web plate 3 and the theoretical height in real time and transmits it to the host computer 601. The host computer 601 controls the third-direction positioning and adjustment structure 603 to rise and fall synchronously according to the height difference, and continuously fine-tunes the overall height of the web plate 3 until the difference between the measured height and the theoretical height is ≤1mm, and the third-direction positioning is completed.

[0101] Step S2: Acquisition of position information of web plate 3

[0102] like Figure 5 As shown, after the web plate 3 completes the external precision positioning, it is still fixed on the positioning fixture 6; at this time, the position information of the web plate 3 is collected with the help of the lifting and bonding fixture 7; the calibration device 8 and the calibration object work together to collect the deformation data of the lifting and bonding fixture 7 itself.

[0103] The hoisting and bonding fixture 7 is a gantry structure with a guide device 702 on the top crossbeam. When the hoisting and bonding fixture 7 is in a static state where the web plate 3 has been adsorbed but not yet lifted into the mold, the position information P1 of the web plate 3 relative to the hoisting and bonding fixture 7 is collected by the measuring device 701 on the guide device 702. At the same time, the deformation compensation information P2 of the fixture is collected in real time by the calibration device 8 outside the workshop in conjunction with the calibration object set on the hoisting and bonding fixture 7, and the absolute spatial position coordinate information P3 of the web plate 3 is calculated.

[0104] In this embodiment, the guiding device 702 is a track and track slider fixed in the internal space of the top crossbeam of the hoisting and bonding fixture 7. The track slider moves through a drive motor and a gear and rack transmission mechanism. The measuring device 701 is a line laser scanner. The calibration device 8 consists of multiple industrial cameras with known spatial reference coordinates. These industrial cameras are arranged parallel to the first direction 101 on a fixed position on the wall outside the workshop mold. The calibration object is a 60mm×60mm reflective target, which is arranged at equal intervals on the track inside the hoisting and bonding fixture 7 (e.g., one every 2m along the length direction).

[0105] It should be noted that in this embodiment, the positions of the calibration device 8 and the calibration object can be interchanged, that is, the calibration object is set in an external fixed position and the calibration device 8 is set on the hoisting and bonding fixture 7.

[0106] (1) Obtain the relative position information P1 of the bonding surfaces on web 3:

[0107] During testing, a guide device 702, mounted on the lifting and bonding fixture 7 and arranged along the first direction 101, works in conjunction with a measuring device 701 to collect data. During data collection, the control terminal sends a measurement command to the measuring device 701, driving it to move and sweep along the guide device 702 in the first direction 101. The measuring device then projects and receives detection signals onto the upper bonding surface of the web 3, acquiring the relative height position of the upper bonding surface in the local measurement coordinate system of the lifting and bonding fixture 7 in real time, and transmitting this information to the control terminal (host computer 601) for recording.

[0108] During specific testing, a local coordinate system C is established using the hoisting and bonding fixture 7 as a local reference. local The line laser scanner slides along the track, using the displacement value of the drive motor as the lateral coordinate and the vertical distance from the receiving surface of the line laser scanner to the bonding surface on the web 3 as the longitudinal height coordinate. The host computer 601 then reconstructs the relative height point cloud data along the entire length. For example, the line laser scanner measures h=245.3mm at 0m from the blade root, h=244.8mm at 1m, and so on, up to the blade tip, forming a relative position point cloud data covering the entire length of the web 3. This data is defined as relative position point cloud data along the track of the hoisting bonding fixture 7 (local coordinate system C). local The relative position information P1 in the local measurement coordinate system established based on ).

[0109] (2) Obtain deformation compensation information P2 for hoisting and bonding fixture 7:

[0110] While the aforementioned measuring device 701 slides along the track, in order to eliminate the bending deformation error caused by the self-weight load and clamping force of the large-span hoisting and bonding fixture 7, an external stable reference is introduced for real-time dynamic calibration. During the sliding scan, the calibration device 8 observes the calibration object in real time and collects relative displacement data, which is transmitted to the control terminal (host computer 601) to calculate the displacement correction amount caused by the deformation of the hoisting and bonding fixture 7 itself.

[0111] During specific testing, a global coordinate system C is established using calibration device 8 as the external global reference. globalAn industrial camera captures real-time images of the target and transmits them to a host computer 601. The host computer 601 calculates the current deflection of the hoisting and bonding fixture 7 at each target location due to deformation caused by its own weight, based on the target's displacement in the image. For example, the target at 0m sinks 0.5mm, at 2m 1.2mm, at 4m 2.1mm, and so on. Since the targets are discontinuously distributed in space (e.g., approximately 40 targets are arranged in an 80m long fixture), and P1 recorded in the host computer 601 is a continuous high-density point cloud (e.g., one measuring point every 1mm), this embodiment uses a quadratic spline interpolation algorithm to fit the discrete target deflection into a continuous deformation curve corresponding one-to-one with P1 along the length direction. This curve is defined as the hoisting and bonding fixture 7 (in the global coordinate system C). global (The following is the deformation compensation information P2.)

[0112] (3) Reconstruct the absolute spatial position information P3 of the bonding surface on web 3:

[0113] In this stage, the computing terminal (host computer 601) mainly performs spatial coordinate system fusion calculations on the relative position information P1 and deformation compensation information P2 collected in the aforementioned steps. Based on the translation vector t and rotation matrix R contained in the deformation compensation information P2, the host computer 601 constructs a spatial homogeneous deformation correction matrix T that transforms the local measurement coordinate system to the global reference coordinate system. match As shown in Equation 1 below:

[0114] Formula 1;

[0115] Where R is a 3×3 spatial rotation correction matrix, used to compensate for the spatial distortion and tilt attitude deviation of the tooling; t is a 3×1 spatial translation correction vector, used to compensate for the overall drift and gravitational sinking deflection of the tooling. Using this matrix, spatial coordinate transformation and deformation error compensation are performed on the local point cloud data P1 to reconstruct the absolute spatial position point cloud data P3=T. match ⋅P1. In the one-dimensional height measurement direction, the above spatial homogeneous transformation calculation can be directly simplified to algebraic subtraction P3=P1−P2. The absolute position data of the upper web 3 is stored as the reference data and defined as P3' (where P3'=P1'−P2').

[0116] During the calculation, deformation correction parameters are used to compensate and correct the measured first relative position data, thereby eliminating the cumulative measurement error caused by the flexible deformation of the tooling, and reconstructing the bonding surface on the web 3 in the global coordinate system C. global The absolute spatial position below.

[0117] Step S3: Gap Calculation and Prediction

[0118] After obtaining the absolute position information P3 of web 3, the host computer 601 compares it spatially with the reference data stored in the database, and combines it with the reference mold closing clearance Z' of the previous web 3 to calculate the predicted mold closing clearance Z of the current web 3. The specific calculation logic is as follows:

[0119] For the first blade, since there is no historical data available for reference, the traditional clay molding method is used to obtain the baseline mold gap Z'. Specifically, five clay measuring points are arranged every meter along the first direction 101 of the web 3. After molding, the compressive thickness of the clay at each measuring point is measured, and the measured gap distribution curve Z' along the entire length of the first blade is obtained by interpolation fitting. At the same time, the absolute spatial position information P3 of the first web 3 collected in step S2 is stored in the database as the baseline absolute position P3' of the next web 3, forming the initial reference benchmark required for subsequent blade calculations.

[0120] For the nth blade (n>1), the host computer 601 retrieves the reference mold closing clearance Z' and reference absolute spatial position P3' of the previous blade (i.e. the (n-1)th blade, or the first blade when n=2) from the database. Combining the absolute spatial position P3 output by step S2 of this blade, the host computer 601 calculates the predicted mold closing clearance Z of this blade point by point along the first direction 101, Z=Z'-(P3-P3') and P3=P1-P2;

[0121] The mold closing clearance of the previous mold plate at a certain position is Z', and the absolute height of the corresponding web plate 3 is P3'; the absolute height of the web plate 3 of this mold plate at that position is P3. Therefore, assuming the inner wall height of the shell remains constant, the change in the height of the web plate 3 is P3 - P3'. If the web plate of this mold plate is higher than the previous mold plate, the clearance decreases; if the web plate of this mold plate is lower than the previous mold plate, the clearance increases.

[0122] After the calculation is completed, the host computer 601 outputs a predicted clearance report in the form of a curve and a table. The acceptable range for the mold closing clearance is 3mm ≤ Z ≤ 10mm. When the predicted value Z exceeds this acceptable range, the host computer 601 outputs an out-of-tolerance warning report to guide the operator in subsequent step S4 to perform pre-compensation by locally thickening (when the clearance is greater than 10mm) or thinning (when the clearance is less than 3mm) the adhesive layer outside the mold. Through the above calculation and output, global prediction and out-of-tolerance warnings for the mold closing clearance are achieved.

[0123] Step S4: Gap Compensation

[0124] The operator reads the predicted gap report output by the host computer 601. If all predicted gaps meet the condition of 3mm≤Z≤10mm, no compensation is required. If there are areas with out-of-tolerance, pre-compensation is performed outside the mold. The compensation is divided into two methods: if the gap is too small (Z<3mm, with the risk of top mold interference): the corresponding section of the flange on the web plate 3 is ground and thinned to reduce the height of the web plate 3 and increase the mold closing gap 4; if the gap is too large (Z>10mm, insufficient adhesive layer thickness): glass fiber and adhesive layer are locally laid on the flange on the web plate 3 to achieve thickening compensation and reduce the mold closing gap 4.

[0125] All compensation processes are completed outside the mold, which reduces the mold occupation, labor, and adhesive material loss caused by multiple hoisting and repeated mold flipping of the SS shell 1 from the source.

[0126] Step S5: Feedback and Adjustment

[0127] The host computer 601 automatically calculates the deviation ΔP=P1−P2−P3' over the entire length of the web 3, where P3=P1−P2. When the fluctuation range of ΔP in a certain section exceeds the preset threshold, the host computer 601 automatically traces the source of the deviation and outputs the corresponding tooling optimization parameters.

[0128] If the deviation is caused by the three-dimensional reference offset of the positioning fixture 6, then the installation positions of the first-direction virtual positioning reference 5, the second-direction positioning monitoring unit 604, and the third-direction positioning monitoring unit 602 shall be corrected.

[0129] If the deviation is caused by the hydraulic cylinder stroke error of the third-direction positioning adjustment structure 603 and the second-direction positioning adjustment structure 606, then the hydraulic system control parameters are corrected.

[0130] If the deviation is caused by deformation of the hoisting and bonding fixture 7 due to long-term use, then optimize the support points of the fixture and adjust the shooting parameters of the calibration device 8 simultaneously.

[0131] When performing the above operation on the next batch of web plates 3, the systematic deviation pre-compensation is completed directly based on the optimized parameters, continuously reducing the fluctuation of the mold closing gap during the batch production process, and forming a production optimization closed loop.

[0132] Step S6: Gap retest

[0133] After compensation, the web plate 3 is rigidly transported to the inside of the PS shell 2 by the hoisting and bonding fixture 7. The lower flange of the web plate 3 is glued and pressure cured to complete the bonding. After the posture of the web plate 3 is fixed, the mold closing gap is re-measured inside the shell with the hoisting and bonding fixture 7 as the reference. If the local points are still out of tolerance, targeted thickening or thinning can be carried out before mold closing to further improve the stability of the predicted gap and ensure 100% gap qualification.

[0134] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various alterations and modifications without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A method for controlling the stability of the mold closing gap of a wind turbine blade, characterized in that, Includes the following steps: Step S1: Precise positioning of the web (3) in one step: By using the pre-arranged web plate positioning reference, web plate positioning monitoring unit and web plate positioning adjustment structure on the outside of the mold, the web plate (3) is positioned to the preset position in three-dimensional space to ensure that the web plate (3) has a consistent posture before entering the mold; Step S2: Acquisition of web plate (3) position information: The position information of the web plate (3) was collected and stored in the database using a hoisting and bonding fixture (7); Step S3: Gap Calculation and Prediction: When bonding the first web plate (3), the reference mold closing gap Z1 of the first web plate (3) is obtained by actual measurement; when bonding the nth (n>1) web plate (3), the reference mold closing gap Z' of the previous web plate (3) is retrieved from the database, and the predicted mold closing gap Z of this web plate (3) is calculated. Step S4: Gap compensation: Based on the calculation results of step S3, the thickness of the adhesive layer corresponding to the out-of-tolerance area of ​​the web (3) is adaptively adjusted so that the adjusted mold closing gap falls into the qualified range.

2. The control method according to claim 1, characterized in that, In step S1, the web plate positioning reference is one or both of a physical positioning reference and a virtual positioning reference; the web plate positioning monitoring unit is one or both of a contact monitoring device and a non-contact monitoring device.

3. The control method according to claim 2, characterized in that, In step S1, the web plate (3) is first coarsely positioned using a physical positioning reference, and then finely positioned using a virtual positioning reference.

4. The control method according to claim 1, characterized in that, In step S1, the web plate positioning reference includes a first direction positioning reference, a second direction positioning reference (605), and a third direction positioning reference; the web plate positioning monitoring unit is provided with a first direction positioning monitoring unit (502), a second direction positioning monitoring unit (604), and a third direction positioning monitoring unit (602); the web plate positioning adjustment structure includes a first direction positioning adjustment structure, a second direction positioning adjustment structure (606), and a third direction positioning adjustment structure (603).

5. The control method according to claim 4, characterized in that, In step S1, the positioning method in the first direction (101) is as follows: A first direction feature point (503) is pre-formed on the web (3). The limiting area formed by dual-beam laser projection is used as the first direction virtual positioning reference (5). The position of the first direction feature point (503) relative to the limiting area is monitored by the first direction positioning monitoring unit (502). The first direction feature point (503) is adjusted to the limiting area by the vehicle to complete the first direction positioning.

6. The control method according to claim 4, characterized in that, In step S1, the positioning method in the second direction (102) is as follows: A square steel is set on the left or right side of the web (3) as a second direction positioning reference (605), and at least two laser rangefinders with known spacing are used as a second direction positioning monitoring unit (604) to measure the distance from the web (3) to the square steel. A hydraulic cylinder-driven second-direction positioning adjustment structure (606) is provided on the other side of the web (3) to push the web (3) to move in the direction of the second-direction positioning reference (605) until the measurement value fed back by the laser range sensor reaches the preset positioning threshold, thus completing the second-direction positioning; The twist angle of the web (3) in the second direction is calculated by the difference between the measured values ​​of the two laser rangefinders.

7. The control method according to claim 4, characterized in that, In step S1, the positioning method on the third direction (103) is as follows: A third-party positioning adjustment structure (603) is provided at the bottom of the web (3) so that the web (3) falls into the upper plane of the third-party positioning adjustment structure (603); At least two laser rangefinders are placed below the adhesive surface of the web plate (3). The distance from the laser rangefinder itself to the adhesive surface of the web plate (3) is measured. The third-direction positioning adjustment structure (603) is driven by a hydraulic cylinder to complete the lifting and lowering adjustment until the difference between the measured value and the theoretical value of the laser rangefinder is within the preset range, thus completing the third-direction positioning.

8. The control method according to claim 1, characterized in that, In step S2, before lifting the web plate (3) using the lifting and bonding fixture (7), the relative position information P1 of the bonding surface on the web plate (3) is collected based on the lifting and bonding fixture (7); the deformation compensation information P2 of the lifting and bonding fixture (7) is collected based on the calibration device (8); P1 and P2 are superimposed and calculated to obtain the absolute spatial position information P3 of the bonding surface on the web plate (3) under the external global reference, and the P3 obtained in this calculation is stored in the database.

9. The control method according to claim 8, characterized in that, It also includes step S5, feedback adjustment: Calculate the difference between the absolute spatial position information P3 of this web (3) and the absolute spatial position information P3' of the previous web (3), and record it as ΔP=P3-P3'; for areas where the change of ΔP exceeds the preset range, perform feedback optimization and adjustment of equipment structure or web positioning parameters.

10. The control method according to claim 1, characterized in that, It also includes step S6, gap retest: After the lower bonding surface of the web plate (3) is bonded to the inner side of the shell, the mold closing gap is re-measured; if the re-measured mold closing gap is within the preset range, the mold is closed normally. If the re-measured mold closing gap exceeds the preset range, the web plate (3) is compensated for the gap until the re-measured mold closing gap reaches the preset range. The last measured re-measured mold closing gap is recorded as the reference mold closing gap Z' of this web plate (3).

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