Wind turbine blade clearance monitoring device, system and generator set

Abstract

The application discloses a kind of wind generating set blade clearance monitoring device, system and generating set, and generating set is provided with monitoring system, this monitoring system includes monitoring device, charge measuring device and data processing terminal, monitoring device includes flexible pipe, multiple positive and negative plates, positive plate and negative plate are distributed in flexible pipe along the axial direction, and respectively with positive wire and negative wire electric connection.Flexible pipe is installed in the PS surface inside wind generating set blade, and from the blade root to the blade tip place.Positive and negative wire connects charge measuring device, and the charge amount of monitoring device is measured by charge measuring device.Charge measuring device sends the charge amount measured to data processing terminal, and data processing terminal determines the blade deformation of blade tip relative to blade root according to charge amount data, to realize the real-time monitoring of blade clearance value.

Description

Technical Field

[0001] This invention relates to the field of monitoring technology for wind turbine generator sets, specifically to a wind turbine generator set blade clearance monitoring device, system, and generator set. Background Technology

[0002] Blade deformation is strongly correlated with blade structural safety. Excessive blade deformation can not only reduce the fatigue life of the blade structure or cause direct damage, but may also lead to insufficient clearance and further collision with the tower, creating potential safety hazards to the overall structure of the wind turbine. Therefore, blade deformation monitoring is particularly important in large wind turbines. Currently, most blade deformation monitoring methods use strain gauges placed at different cross-sections along the blade axis. However, this approach is costly and requires sophisticated construction techniques, so it is generally only used in prototype testing and cannot achieve full life-cycle monitoring of the blade. Secondly, radar or video methods are used to monitor the blade's shape or tip, mainly for blade clearance protection under extreme conditions. However, these methods, when deployed externally, require high environmental adaptability, and currently, neither radar nor video solutions can achieve all-weather monitoring.

[0003] Patent CN105822508A discloses a method for measuring blade deformation by arranging wires inside the blade. This method can only monitor expansion and contraction along the blade's axial direction, but is insensitive to changes in the blade's curvature. The blade tip is flat and slender, resulting in small expansion and contraction but large curvature changes during deformation. Although expansion and contraction are strongly correlated after blade production and finalization, measuring only the expansion / contraction change is clearly less sensitive, and the method disclosed in this patent has certain limitations in practical application. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention proposes a wind turbine blade clearance monitoring device, system, and generator set, capable of monitoring blade expansion and contraction as well as curvature changes. The specific technical solution is as follows:

[0005] In a first aspect, a wind turbine blade clearance monitoring device is provided, comprising:

[0006] Flexible tube;

[0007] Multiple positive electrode plates and multiple negative electrode plates are arranged axially inside the flexible tube, and the positive electrode plates and negative electrode plates are arranged alternately along the central axis of the flexible tube.

[0008] Both the positive and negative leads are arranged along the flexible tube and are electrically connected to the positive and negative plates, respectively.

[0009] In conjunction with the first aspect, in a first possible implementation of the first aspect, the flexible tube includes an outer tube and an inner tube, and the positive electrode plate and the negative electrode plate are fixed inside the inner tube.

[0010] In conjunction with the first aspect, in a second possible implementation of the first aspect, the elastic modulus of the flexible tube is less than the elastic modulus of the wind turbine blade.

[0011] In conjunction with the first aspect, in a third possible implementation of the first aspect, the adjacent positive and negative plates are spaced 2 mm apart.

[0012] In conjunction with the first aspect, in a fourth possible implementation of the first aspect, the positive and negative conductors are arranged in an S-shape along the flexible tube.

[0013] In conjunction with the first aspect, in the fifth possible implementation of the first aspect, the positive and negative conductors are symmetrically distributed at 180 degrees on the cross-section of the flexible tube.

[0014] Secondly, a wind turbine blade clearance monitoring system is provided, comprising:

[0015] The wind turbine blade clearance monitoring device described in the first aspect and any one of the first to fifth implementable methods of the first aspect;

[0016] A charge measuring device, electrically connected to the positive and negative wires, is configured to measure the charge data of the wind turbine blade clearance monitoring device.

[0017] The data processing terminal is connected to the charge measurement device and configured to determine the blade clearance value of the wind turbine generator set based on the charge data.

[0018] In conjunction with the second aspect, in a first possible implementation of the second aspect, the data processing terminal includes:

[0019] The data acquisition module is configured to acquire a large amount of experimental data and charge data measured by the charge measurement device. The experimental data includes charge experimental data and the distance from the blade tip to the ground.

[0020] The curve fitting module is configured to perform curve fitting based on a large amount of experimental data to obtain the curve fitting equation between charge and distance from the ground.

[0021] The data calculation module is configured to calculate the blade clearance value based on the curve fitting equation obtained by the curve fitting module, according to the charge data, blade installation cone angle, and main shaft elevation angle.

[0022] Thirdly, a wind turbine generator set is provided, comprising:

[0023] As described in the second aspect, in the wind turbine blade clearance monitoring system, the flexible tube is disposed on the PS surface inside the wind turbine blade and extends along the blade from the blade root to the blade tip.

[0024] In conjunction with the third aspect, in the first possible implementation of the third aspect, the flexible tube is fixed to the blade using a multi-point fixing method.

[0025] Beneficial effects: When the wind turbine blade clearance monitoring device, system and generator set of the present invention are used, the capacitance value of the monitoring device installed on the blade will change when the wind turbine blade undergoes expansion or curvature changes. By measuring the charge of the monitoring device, the blade deformation of the blade tip relative to the blade root caused by the expansion or curvature changes can be determined, thus realizing real-time monitoring of the blade clearance value. Attached Figure Description

[0026] To more clearly illustrate the specific embodiments of the present invention, the accompanying drawings used in the specific embodiments will be briefly described below. In all the drawings, the elements or parts are not necessarily drawn to scale.

[0027] Figure 1 This is a schematic diagram of the structure of a wind turbine blade clearance monitoring device provided in an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the structure of a wind turbine blade clearance monitoring system provided in an embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of the mounting cone angle of the wind turbine blades and the structure of the main shaft.

[0030] Figure label:

[0031] 1-Flexible tube, 2-Positive electrode plate, 3-Negative electrode plate, 4-Positive electrode wire, 5-Negative electrode wire, 6-Charge measuring device, 7-Data processing terminal. Detailed Implementation

[0032] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the technical solution of the present invention and are therefore intended to limit the scope of protection of the present invention.

[0033] like Figure 1 The schematic diagram shown is of a wind turbine blade clearance monitoring device. The monitoring device includes:

[0034] Flexible tube 1;

[0035] Multiple positive electrode plates 2 and multiple negative electrode plates 3 are arranged axially inside the flexible tube 1, and the positive electrode plates 2 and negative electrode plates 3 are arranged alternately along the central axis of the flexible tube 1.

[0036] Positive electrode wire 4 and negative electrode wire 5 are both arranged along the flexible tube 1 and are electrically connected to the positive electrode plate 2 and the negative electrode plate 3, respectively.

[0037] Specifically, the monitoring device consists of a flexible tube 1, multiple positive plates 2, multiple negative plates 3, a positive electrode wire 4, and a negative electrode wire 5. All positive plates 2 and negative plates 3 are axially distributed within the flexible tube 1, with their surfaces perpendicular to the central axis of the flexible tube 1. The positive plates 2 and negative plates 3 are sequentially spaced along the flexible tube 1 and electrically connected to the positive electrode wire 4 and negative electrode wire 5, respectively, which are arranged along the flexible tube 1.

[0038] The entire flexible tube 1 can be installed inside the PS surface of the wind turbine blade, i.e., the windward side, and 0.5 meters from the blade root to the blade tip. The positive and negative wires 5 can be led out from the blade root and connected to a constant voltage source. A charge measuring device 6, such as a charge meter, can be connected in series between the constant voltage source and the positive and negative wires 5.

[0039] In this way, the expansion and contraction, as well as the curvature changes, of the blade can be transmitted to the flexible tube 1, causing it to expand, contract, or bend. This results in a change in the capacitance of the monitoring device, which in turn causes a change in the charge measured by the charge meter. Through experimental calibration, the correlation curve between the charge and the expansion and contraction, and curvature changes of the blade can be determined. By combining the measured charge with the calibrated correlation curve, the blade deformation relative to the blade root can be determined. The blade clearance value can then be calculated using this deformation, thus enabling real-time monitoring of the blade clearance value.

[0040] In this embodiment, optionally, the flexible tube 1 includes an outer tube and an inner tube, and the positive electrode plate 2 and the negative electrode plate 3 are fixed inside the inner tube. The outer tube can serve as a protector and insulator, the inner tube can be used to fix the positive and negative electrode plates 3, and the positive and negative electrode wires 5 can be disposed between the inner tube and the outer tube.

[0041] In this embodiment, optionally, the elastic modulus of the flexible tube 1 is less than that of the wind turbine blade. Specifically, both the inner and outer tubes can be made of the same elastic material, and the elastic modulus of this material needs to be much smaller than that of the material used in the wind turbine blade. In this way, placing the measuring device on the wind turbine blade will not change the stiffness of the blade body and will not have a significant impact on the operation of the blade.

[0042] In this embodiment, optionally, considering the balance between sensitivity and cost control for monitoring needs, the adjacent positive electrode plate 2 and negative electrode plate 3 are spaced 2 mm apart. It should be understood that this embodiment is only illustrative with an example of a 2 mm spacing between the positive electrode plate 2 and negative electrode plate 3, but the present invention is not limited to this, and the spacing between the positive electrode plate 2 and negative electrode plate 3 can also be other values.

[0043] In this embodiment, optionally, the positive electrode wire 4 and the negative electrode wire 5 are arranged in an S-shape along the flexible tube 1. Specifically, the positive electrode wire 4 and the negative electrode wire 5 are routed in an S-shape between the inner and outer tubes, which allows for a certain amount of expansion and contraction allowance to ensure that the wires will not break when the blade bends or expands.

[0044] In this embodiment, optionally, since the wires are S-shaped, the positive wire 4 and the negative wire 5 are arranged on the same side, which may easily overlap and cause a short circuit. Therefore, the positive wire 4 and the negative wire 5 are symmetrically distributed at 180 degrees on the cross-section of the flexible tube 1. In this way, a large space is reserved between the positive wire 4 and the negative wire 5 to avoid the positive wire 4 and the negative wire 5 from overlapping.

[0045] like Figure 2 The diagram shown illustrates a wind turbine blade clearance monitoring system, which includes:

[0046] The aforementioned wind turbine blade clearance monitoring device;

[0047] The charge measuring device 6 is electrically connected to the positive electrode wire 4 and the negative electrode wire 5, and is configured to measure the charge data of the wind turbine blade clearance monitoring device.

[0048] The data processing terminal 7 is connected to the charge measuring device 6 by signal and is configured to determine the blade clearance value of the wind turbine generator set based on the charge data.

[0049] Specifically, the monitoring system consists of the aforementioned monitoring device, charge measuring device 6, and data processing terminal 7. The flexible tube 1 of the monitoring device can be installed inside the wind turbine blade on the PS surface, i.e., the windward side, extending 0.5 meters from the blade root to the blade tip. Positive and negative leads 5 can be led out from the blade root and connected to the charge measuring device 6. The charge measuring device 6 includes a constant voltage source and a charge meter. After the positive and negative leads 5 exit the flexible tube 1, they can be connected to the positive and negative terminals of the constant voltage source, respectively. A charge meter can be connected between the positive and negative terminals of the constant voltage source to measure the charge on the capacitor of the monitoring device.

[0050] Since the expansion, contraction, and curvature changes of the blade can be transmitted to the flexible tube 1, causing it to expand, contract, or bend, this results in a change in the capacitance of the monitoring device, and consequently, a change in the charge measured by the charge meter. The charge meter can send the measured charge to the data processing terminal 7, which can pre-store correlation curves between the charge and the expansion, contraction, and curvature changes of the blade, determined through experimental calibration. Combining the received charge data and the experimentally calibrated correlation curves, the data processing terminal 7 can determine the blade deformation relative to the blade root, and calculate the blade clearance value using this deformation, thus achieving real-time monitoring of the blade clearance value.

[0051] In this embodiment, optionally, the data processing terminal 7 includes:

[0052] The data acquisition module is configured to acquire a large amount of experimental data and charge data measured by the charge measuring device 6. The experimental data includes charge experimental data and the distance from the blade tip to the ground.

[0053] The curve fitting module is configured to perform curve fitting based on a large amount of experimental data to obtain the curve fitting equation between charge and distance from the ground.

[0054] The data calculation module is configured to calculate the blade clearance value based on the curve fitting equation obtained by the curve fitting module, according to the charge data, blade installation cone angle, and main shaft elevation angle.

[0055] Specifically, the data processing terminal 7 consists of a data acquisition module, a curve fitting module, and a data calculation module. The data acquisition module can acquire experimental data obtained from multiple experiments and charge data measured in real time by a charge meter. The experimental data includes charge data and ground clearance data obtained through loading experiments on the blades.

[0056] During the loading experiment on the blade, the blade was placed horizontally with the PS (power point) facing upwards. The greater the load, the greater the blade deformation, and the closer the blade tip was to the ground. Therefore, the distance between the blade tip and the ground can effectively reflect the blade deformation. Throughout the experiment, the charge data measured by the charge gauge and the distance between the blade tip and the ground were recorded. By combining this data with the height of the blade root at a fixed point on the experimental platform, the blade deformation relative to the blade root could be calculated.

[0057] To avoid complex data calculations, a curve fitting module can be used to fit a large amount of experimental data to derive the curve fitting equation between charge and distance from the ground. The data calculation module, combining the real-time measured charge data and the curve fitting equation, can calculate the blade deformation relative to the blade root. Then, by combining the blade installation cone angle and main shaft elevation angle after the blade is installed in the unit, the blade deformation can be converted into the distance between the blade tip and the tower, i.e., the blade clearance value.

[0058] The specific calculations are as follows:

[0059] like Figure 3 As shown, let the blade length be L1, the blade mounting cone angle be α, the main shaft elevation angle be β, the horizontal distance from the blade root to the tower be L2 (at the height of the tower at the blade tip), and the blade deformation be D1. Then the blade clearance D2 can be calculated using the following formula.

[0060] D2=L1*Sin(α+β)+L2-D1.

[0061] A wind turbine generator set, comprising:

[0062] In the aforementioned wind turbine blade clearance monitoring system, the flexible tube 1 is installed on the PS surface inside the wind turbine blade and extends along the blade from the blade root to the blade tip.

[0063] Specifically, the wind turbine generator set is equipped with the aforementioned monitoring system. The flexible tube 1 of the monitoring device can be installed inside the wind turbine generator blade on the PS surface, i.e., the windward side, extending 0.5 meters from the blade root to the blade tip. Positive and negative conductors 5 can be led out from the blade root and connected to a charge measuring device 6. The charge measuring device 6 includes a constant voltage source and a charge meter. After the positive and negative conductors 5 exit the flexible tube 1, they can be connected to the positive and negative terminals of the constant voltage source, respectively. A charge meter can be connected between the positive and negative terminals of the constant voltage source to measure the charge quantity of the monitoring device.

[0064] Since the expansion, contraction, and curvature changes of the blade can be transmitted to the flexible tube 1, causing the flexible tube 1 to expand, contract, or bend, this results in a change in the capacitance of the monitoring device, and consequently, a change in the charge measured by the charge meter. The charge meter can send the measured charge to the data processing terminal 7, which can pre-store the correlation curve between the charge and the expansion, contraction, and curvature changes of the blade, determined through experimental calibration. By combining the received charge data and the experimentally calibrated correlation curve, the data processing terminal 7 can determine the blade deformation from the blade tip to the blade root, achieving real-time monitoring of the blade clearance value.

[0065] In this embodiment, optionally, the flexible tube 1 is fixed to the blade at multiple points to avoid affecting the performance.

[0066] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A wind turbine blade clearance monitoring system, characterized in that, This includes a wind turbine blade clearance monitoring device, a charge measurement device, and a data processing terminal; The wind turbine blade clearance monitoring device includes a flexible tube, multiple positive plates, multiple negative plates, a positive wire, and a negative wire; Multiple positive electrode plates and multiple negative electrode plates are arranged axially inside the flexible tube, and the positive electrode plates and negative electrode plates are arranged alternately along the central axis of the flexible tube. Both the positive and negative leads are arranged along the flexible tube and are electrically connected to the positive and negative plates, respectively. A charge measuring device, electrically connected to the positive and negative wires, is configured to measure the charge data of the wind turbine blade clearance monitoring device. A data processing terminal is connected to the charge measurement device and configured to determine the blade clearance value of the wind turbine generator set based on the charge data. The data processing terminal includes a data acquisition module, a curve fitting module, and a data calculation module. The data acquisition module is configured to acquire a large amount of experimental data and charge data measured by the charge measurement device. The experimental data includes charge experimental data and the distance from the blade tip to the ground. The curve fitting module is configured to perform curve fitting based on a large amount of experimental data to obtain the curve fitting equation between charge and distance from the ground. The data calculation module is configured to calculate the blade clearance value based on the curve fitting equation obtained by the curve fitting module, according to the charge data, blade installation cone angle, and main shaft elevation angle.

2. The wind turbine blade clearance monitoring system according to claim 1, characterized in that, The flexible tube includes an outer tube and an inner tube, and the positive electrode plate and the negative electrode plate are fixed inside the inner tube.

3. The wind turbine blade clearance monitoring system according to claim 1, characterized in that, The elastic modulus of the flexible tube is less than that of the wind turbine blade.

4. The wind turbine blade clearance monitoring system according to claim 1, characterized in that, The positive and negative plates are spaced 2 mm apart.

5. The wind turbine blade clearance monitoring system according to claim 1, characterized in that, The positive and negative conductors are arranged in an S-shape along the flexible tube.

6. The wind turbine blade clearance monitoring system according to claim 1, characterized in that, The positive and negative conductors are symmetrically distributed at 180 degrees on the cross-section of the flexible tube.

7. A wind turbine generator set, characterized in that, include: The wind turbine blade clearance monitoring system as described in claim 1, wherein the flexible tube is disposed on the PS surface inside the wind turbine blade and extends along the blade from the blade root to the blade tip.

8. The wind turbine generator set according to claim 7, characterized in that, The flexible tube is fixed to the blade using a multi-point fixing method.

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