Icing measuring device and method for fan blade and wind generating set

Abstract

The invention belongs to the related technical field of wind power generation, and discloses an icing measuring device and method for a fan blade and a wind generating set. The icing measuring device comprises a pressure sensor and a processor, and the pressure sensor is arranged on the surface of the blade; the pressure sensor is used for measuring the pressure data of the upper icing when the blade rotates to the horizontal position around the axis of the hub and rotates to the upper surface of the blade around the blade root axis of the blade, and the processor is used for collecting the pressure data and calculating the gravity data of the upper icing according to the pressure data so as to obtain icing parameter information. The pressure sensor is arranged on the surface of the blade, when the blade is located at the horizontal position and the pressure sensor is located above the blade, pressure data of icing above the pressure sensor can be directly measured and obtained, then icing parameter information is calculated and obtained, the measurement process is simplified, the complexity of the device is reduced, possible error sources can be reduced, and the measurement accuracy is improved. The measurement accuracy is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field related to wind power generation, and more specifically, relates to an ice coating measurement device and method for wind turbine blades and a wind turbine generator set. Background Art

[0002] Wind power generation is a clean and renewable energy source that has been widely used around the world in recent years. However, during the process of wind power generation, wind turbine blades often encounter icing problems, especially in low wind speed and high humidity environments. Blade icing can lead to a decrease in blade aerodynamic performance, increase the operating risk of wind turbines, and even cause safety accidents. Therefore, accurate detection of blade icing parameters is of great significance for preventing and handling wind power equipment failures.

[0003] At present, blade ice detection technology mainly relies on wired active sensors and image processing technology. Among them, sensor technology is the most commonly used method. By installing temperature sensors, humidity sensors, etc. on the surface of the blade, the temperature and humidity changes on the blade surface are monitored in real time, so as to determine whether the blade is covered with ice and analyze parameters such as the thickness of the ice. Image processing technology analyzes the image of the blade surface, extracts the characteristic information of the blade surface, and then determines the ice condition of the blade. However, there are still some problems with the existing blade ice detection technology: First, sensor technologies such as temperature and humidity sensors are greatly affected by environmental factors and are prone to errors. Secondly, image processing technology has high requirements for image quality. When the image quality is poor, it will affect the accuracy of the detection results. In addition, most of the existing blade ice detection technologies can only perform qualitative analysis and cannot achieve accurate measurement of ice parameters. Summary of the invention

[0004] In view of the above defects or improvement needs of the prior art, the present invention provides an ice coverage measurement device, method and wind turbine generator set for wind turbine blades, which are used to solve the problem that the detection results of the existing blade ice coverage detection technology are prone to errors and low accuracy.

[0005] To achieve the above-mentioned purpose, according to a first aspect of the present invention, there is provided an ice covering measurement device for wind turbine blades, comprising a pressure sensor and a processor, wherein the pressure sensor is arranged on the surface of the blade, and the pressure sensor is used to measure the pressure data of the ice covering above when the blade rotates around the hub axis to a horizontal position and rotates around the root axis of the blade until the pressure sensor is located on the upper surface of the blade; the processor is used to collect the pressure data measured by the pressure sensor and infer the gravity data of the ice covering above based on the pressure data, thereby obtaining ice covering parameter information.

[0006] The ice covering measurement device for wind turbine blades provided in accordance with the present invention also includes an elastic ring sleeved on the surface of the blade, a plurality of the elastic rings are arranged along the span direction of the blade, each of the elastic rings is respectively provided with the pressure sensor to form a sensor ring, and each of the sensor rings is respectively fixed to the surface of the blade by the elastic force of the elastic ring.

[0007] According to the ice coating measurement device for wind turbine blades provided by the present invention, the pressure sensor on each of the sensor rings includes at least one of a leading edge point sensor, a trailing edge point sensor and a blade element point sensor;

[0008] The leading edge point sensor is arranged on the leading edge line of the blade element, and is used to obtain ice coating parameter information at the leading edge line of the blade element;

[0009] The trailing edge point sensor is arranged on the trailing edge line of the blade element, and is used to obtain ice coating parameter information at the trailing edge line of the blade element;

[0010] The blade element point sensor is arranged on the side surface of the blade between the leading edge line of the blade element and the trailing edge line of the blade element, and is used to obtain ice coating parameter information at the side surface.

[0011] According to the ice coating measuring device for wind turbine blades provided by the present invention, the elastic ring is formed by two elastic half rings that are detachably connected.

[0012] According to the ice-covering measuring device for wind turbine blades provided by the present invention, the pressure sensor is a wireless passive sensor, and the pressure sensor is embedded in the elastic ring;

[0013] And / or, the two elastic half rings of the elastic ring are connected at the connection point by a hook structure.

[0014] According to the ice-covering measuring device for wind turbine blades provided by the present invention, the processor is specifically used to obtain thickness information of the ice covering the upper part according to gravity data of the ice covering the upper part and size parameter data of the pressure sensor.

[0015] According to the ice coating measurement device for wind turbine blades provided by the present invention, the processor is further used to obtain ice-coated airfoil information after ice coating based on the thickness information of ice coating above the pressure sensor.

[0016] According to the ice coating measurement device for wind turbine blades provided by the present invention, when the pressure sensor on the sensor ring includes a leading edge point sensor and / or a trailing edge point sensor, the thickness information of ice coating above the leading edge point sensor or the trailing edge point sensor is respectively:

[0017]

[0018] Among them, ti is the ice thickness at the leading edge point sensor or trailing edge point sensor on the i-th sensor ring; F i w is the pressure data obtained by the leading edge point sensor or the trailing edge point sensor on the i-th sensor ring; i is the width of the leading edge point sensor or trailing edge point sensor on the i-th sensor ring, and the width direction is the wingspan direction; l i The length of the leading edge point sensor or the trailing edge point sensor on the i-th sensor ring, where the length direction is perpendicular to the wingspan direction; g is the local gravity acceleration; ρ is the ice density;

[0019] When the pressure sensor on the sensor ring includes a blade point sensor, the thickness information of ice above the blade point sensor is specifically:

[0020]

[0021] Among them, t ij is the ice thickness at the jth blade point sensor on the i-th sensor ring; F ij is the pressure data obtained by the j-th blade point sensor on the i-th sensor ring; w ij is the width of the jth blade point sensor on the i-th sensor ring, and the width direction is the wingspan direction; l ij The length of the jth blade point sensor on the i-th sensor ring; β ij is the angle between the tangent line of the j-th blade point sensor on the i-th sensor ring and the horizontal line.

[0022] According to a second aspect of the present invention, a method for measuring ice coating on a wind turbine blade is provided. Based on any one of the above-mentioned devices for measuring ice coating on a wind turbine blade, the method for measuring ice coating comprises:

[0023] Rotate the blade around the hub axis so that the blade is in a horizontal position, and rotate the blade around the blade root axis so that the pressure sensor is located on the upper surface of the blade;

[0024] Collecting pressure data measured by the pressure sensor;

[0025] Ice coating parameter information at the pressure sensor is acquired according to the pressure data.

[0026] According to a third aspect of the present invention, there is provided a wind turbine generator set, comprising blades, on which is provided any one of the above-mentioned ice coating measurement devices for wind turbine blades.

[0027] In general, compared with the prior art, the above technical solutions conceived by the present invention provide an ice measurement device and method for wind turbine blades and a wind turbine generator set:

[0028] 1. The pressure sensor is arranged on the surface of the blade. When the blade is in a horizontal position and the pressure sensor is located above the blade, the pressure data of the ice above the pressure sensor can be directly measured and obtained, and then the ice parameter information can be calculated and obtained. Compared with the existing ice detection technology that obtains parameters indirectly by temperature sensors, humidity sensors and image processing, the present invention proposes to select ice pressure as the physical quantity to be measured, and can directly measure and obtain ice-related gravity information, so that the actual parameter information of the ice layer can be reflected more accurately. In addition, ice pressure detection only needs to measure pressure, and does not need to monitor other physical quantities such as temperature and humidity, which simplifies the measurement process, reduces the complexity of the device, and is also conducive to reducing possible error sources and improving measurement accuracy.

[0029] 2. An elastic ring is used to set and fix the pressure sensor, that is, the pressure sensor is set on the elastic ring to form a sensor ring, which is tightly attached to the surface of the blade and can accurately locate the position to be measured; the use of an elastic ring to connect the pressure sensor makes the sensor ring have excellent flexibility and stretchability, and can fit tightly on the surface of the blade to adapt to the deformation and movement of the blade in various environments. This design ensures stable contact between the pressure sensor and the blade, thereby effectively improving the accuracy of the measurement;

[0030] 3. It is proposed that the pressure sensor on the sensor ring may include at least one of a leading edge point sensor, a trailing edge point sensor and a blade element point sensor, which can be flexibly set according to actual needs, and a method for implementing ice coverage measurement using pressure sensors at different parts of the blade is provided, which can realize ice coverage measurement at multiple parts of the blade, and is conducive to more comprehensive and accurate acquisition of ice coverage information of the blade;

[0031] 4. With the help of wireless passive pressure sensors for detection, there is no need to lay complex cable lines, which greatly simplifies the installation and maintenance process. This not only reduces the installation cost, but also avoids detection failures caused by line problems. In contrast, wired active sensors require laying a large number of wires, which not only has high installation costs but is also difficult to maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the arrangement of a pressure sensor in an ice coating measurement device for wind turbine blades provided by the present invention;

[0033] Figure 2 is a schematic diagram of a first arrangement of a sensor ring provided by the present invention on a blade;

[0034] Figure 3 is a schematic diagram of a second arrangement of the sensor ring provided by the present invention on a blade;

[0035] Figure 4It is a front view of the sensor ring provided by the present invention and a schematic diagram of the dimensions of the blade element point sensor;

[0036] Figure 5 is a side view of a sensor ring provided by the present invention;

[0037] Figure 6 is a top view of the sensor ring provided by the present invention;

[0038] Figure 7 It is a schematic diagram of an ice-covered airfoil at the leading edge line of a blade after ice-covered provided by the present invention;

[0039] Figure 8 is a side view schematic diagram of an ice-covered airfoil of a blade after ice-covering provided by the present invention;

[0040] Fig. 9 This is a schematic diagram of the ice measurement principle of the blade point sensor provided by the present invention:

[0041] Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0042] 1-leading edge point sensor; 2-blade point sensor; 3-elastic ring; 4-connecting structure; 5-trailing edge point sensor. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] See also Figure 1 , this embodiment 1 provides an ice coating measurement device for wind turbine blades, the ice coating measurement device includes a pressure sensor and a processor, the pressure sensor is arranged on the surface of the blade, the pressure sensor is used to measure the pressure data of ice coating above when the blade rotates around the hub axis to a horizontal position and rotates around the root axis of the blade until the pressure sensor is located on the upper surface of the blade, the processor is used to collect the pressure data measured by the pressure sensor and infer the gravity data of ice coating above according to the pressure data, thereby obtaining ice coating parameter information.

[0045] In this embodiment, a pressure sensor is used to measure and obtain ice parameter information on the surface of the wind turbine blade. The pressure sensor is set on the surface of the blade, and the blade can be rotated around the hub axis to a horizontal position. The blade is in a horizontal position, that is, the cross-sectional axis of the blade root is in a horizontal state. Then the blade can be rotated around its own cross-sectional axis of the blade root, that is, the pitch angle is adjusted, so that the pressure sensor to be measured is located on the upper surface of the blade, that is, facing upward. The blade itself can be specifically rotated until the pressure sensor is located above the blade, so that the pressure sensor to be measured can obtain the pressure data of the ice above. The pressure data can reflect the gravity of the ice above, and the gravity information of the ice above can be obtained by measuring the pressure sensor. Other parameter information of the ice above can also be calculated based on the gravity information of the ice above, such as judging whether there is ice and ice thickness parameters, so as to achieve ice measurement.

[0046] Furthermore, an ice coverage measurement device for wind turbine blades also includes an elastic ring 3 sleeved on the surface of the blade, a plurality of the elastic rings 3 are arranged along the span direction of the blade, each of the elastic rings 3 is respectively provided with the pressure sensor to form a sensor ring, and each of the sensor rings is respectively fixed to the blade surface by the elastic force of the elastic ring 3.

[0047] like Figure 2 As shown, the pressure sensor is mounted on the blade in the form of a sensor ring, and each sensor ring may be provided with one or more pressure sensors, along the span direction. Figure 2 In the x-direction, multiple sensor rings can be set on the surface of the blade to measure ice coverage at multiple different parts of the blade. The sensor rings can be set directly on the surface of the blade, which can facilitate the installation of the pressure sensor on the surface of the blade without damaging the surface of the blade.

[0048] Further, the pressure sensor on each of the sensor rings includes at least one of a leading edge point sensor 1, a trailing edge point sensor 5, and a blade element point sensor 2;

[0049] The leading edge point sensor 1 is arranged on the leading edge line of the blade element of the blade, and is used to obtain ice coating parameter information at the leading edge line of the blade element; the leading edge point sensor 1 is used to measure the pressure data of ice coating above when the blade is in a horizontal position and the leading edge point sensor 1 is located above the blade, and then obtain the ice coating parameter information at the leading edge line of the blade element according to the pressure data;

[0050] The trailing edge point sensor 5 is arranged on the trailing edge line of the blade element of the blade, and is used to obtain ice coating parameter information at the trailing edge line of the blade element; the trailing edge point sensor 5 is used to measure the pressure data of ice coating above when the blade is in a horizontal position and the trailing edge point sensor 5 is located above the blade, and then obtain the ice coating parameter information at the trailing edge line of the blade element according to the pressure data.

[0051] The blade point sensor 2 is arranged on the side of the blade between the leading edge line of the blade and the trailing edge line of the blade, and is used to obtain ice coverage parameter information at the side; the blade point sensor 2 is used to measure the pressure data of ice coverage above when the blade is in a horizontal position and the blade point sensor 2 is located above the blade, that is, the side of the blade is facing upward (which can be achieved by adjusting the pitch angle), and then obtain the ice coverage parameter information on the side of the blade based on the pressure data.

[0052] When the sensor ring is provided with a blade element point sensor 2, a plurality of blade element point sensors 2 can be respectively provided at the corresponding positions of the sensor ring and each side surface of the blade. When the sensor ring is provided with the above three sensors, the leading edge point sensor 1 is correspondingly located at the leading edge line of the blade element, the trailing edge point sensor 5 is correspondingly located at the trailing edge line of the blade element, and the blade element point sensor 2 is correspondingly located at the side surface, and the elastic ring 3 can better fix the position of each sensor.

[0053] In some specific embodiments, the pressure sensor is arranged at the leading edge line of the blade element or the trailing edge line of the blade element, or the pressure sensor is arranged at both the leading edge line and the trailing edge line of the blade element, and a plurality of blade element point sensors 2 may be arranged at the corresponding positions of each sensor ring and each side surface of the blade, so that when the blade is rotated to the horizontal position, the blade element leading edge line, the trailing edge line and the side surface of the blade element may be rotated upward respectively by adjusting the pitch angle to realize ice measurement at different positions. Figure 1 and Figure 2 In the embodiment shown, a leading edge point sensor 1 and a trailing edge point sensor 5 are provided; Figure 3 In the illustrated embodiment, a leading edge point sensor 1 and a plurality of blade element point sensors 2 are provided.

[0054] Furthermore, if Figure 4 and Figure 5 As shown, the elastic ring 3 is formed by two elastic half rings that are detachably connected.

[0055] In this embodiment, the pressure sensor is a wireless passive sensor. The sensor ring is a ring-shaped wireless passive sensor. Multiple sensor rings form a ring-shaped body-attached wireless passive pressure sensor group. The ring-shaped body-attached wireless passive pressure sensor group is composed of a plurality of ring-shaped wireless passive sensors, each of which is composed of two semi-ring-shaped wireless passive pressure sensors connected end to end and attached to the surface of the blade.

[0056] In some specific embodiments, for each annular wireless passive sensor, there is a pressure detection sensor at the leading edge point of the blade element, and a certain number of small wireless passive sensors at the blade element points are arranged at the remaining positions. That is, each sensor ring is provided with a leading edge point sensor 1 and multiple blade element point sensors 2. It is worth noting that the sensors are arranged at the leading edge point because the leading edge point design is usually more rounded, and the ice thickness is larger (easy to be covered with ice), while the trailing edge design is sharper. Although it will also be covered with ice, its thickness can be ignored. The rest is a connecting component, that is, an elastic member. The elastic member can be an elastic band made of elastic material. When the annular wireless passive sensor is at different positions of the blade, the elastic material can be appropriately and naturally contracted to ensure that the sensor is close to the surface of the blade.

[0057] In this embodiment, the pressure sensor is set as a wireless passive sensor, and detection is performed with the help of the wireless passive sensor, which has the characteristics of low power consumption and long life. Since the wireless passive sensor does not require continuous power supply, the energy consumption is extremely low, thereby extending the service life of the sensor. In contrast, wired active sensors require regular battery replacement or charging, which not only increases maintenance costs, but may also cause detection interruptions. An elastic ring 3 is set to connect the sensors to form a sensor ring, and the sensor ring can be fixed on the surface of the blade by elastic force, which is convenient for the setting, positioning and position adjustment of the pressure sensor, and is also conducive to improving the setting applicability of the sensor ring. The sensor fixing method will not cause damage to the blade, and is convenient for installation and disassembly.

[0058] Furthermore, the wireless passive pressure sensor can be powered by a signal source, a vibration power supply, or a solar power supply, and can use wireless communication such as Bluetooth for signal transmission. The specific wireless passive form is not limited.

[0059] Specifically, the pressure sensor is embedded in the elastic ring 3; a small opening can be opened on the surface of the elastic ring 3, and the sensor can be embedded inside the elastic member, and the fixing method is simple and reliable. The leading edge point sensor 1, the trailing edge point sensor 5 and the blade element point sensor 2 can also be set as flexible sensors, which are conducive to better fitting on the blade surface and improving the reliability of position fixation.

[0060] The two elastic half rings of the elastic ring 3 are connected at the connection point by a hook structure. Figure 4 and Figure 5 A connection structure 4 is provided between two elastic half rings in any sensor ring, and the connection of the two elastic half rings is realized through the connection structure 4, thereby forming a sensor ring. The connection structure 4 can be a hook structure, and multiple hooks can be provided between the two elastic half rings to realize a detachable connection of the two elastic half rings. The connection method is simple and easy to install and disassemble. The connection structure 4 can also be in other forms for the purpose of achieving a firm connection, which is not specifically limited.

[0061] Furthermore, the ice covering measurement device for wind turbine blades also includes a processor, which is specifically used to obtain gravity data of the ice covering above based on the pressure data of the ice covering above measured by the pressure sensor; and to obtain thickness information of the ice covering above based on the gravity data of the ice covering above and the dimensional parameter data of the pressure sensor.

[0062] The processor is a data processing module. The processor is connected to the pressure sensor in communication, and can receive the pressure data measured by the pressure sensor, and obtain the thickness information of the ice above through calculation. The specific process of obtaining the thickness information of the ice above is: deriving the volume calculation formula of the ice above the pressure sensor according to the size parameters of the pressure sensor, deriving the gravity calculation formula according to the volume calculation formula, obtaining the actual gravity data of the ice above according to the pressure data, and then obtaining the thickness information of the ice above according to the gravity calculation formula and the actual gravity data.

[0063] When the pressure sensor includes the leading edge point sensor 1 and / or the trailing edge point sensor 5, the pressure data collected by the leading edge point sensor 1 and the trailing edge point sensor 5 can be directly used as the gravity data of the ice covering the upper part, thereby obtaining the thickness information of the ice covering the upper part; specifically, the ice covering the upper part of the pressure sensor can be equivalent to a cube to derive the volume calculation formula, that is, the volume calculation formula is the product of the width, length and ice thickness of the pressure sensor. When the pressure sensor includes the blade element point sensor 2, the pressure data collected by the blade element point sensor 2 is used as the component force of the gravity data of the ice covering the upper part, and then according to the angle between the tangent line of the blade element point sensor 2 on the blade and the horizontal line, the gravity data can be derived according to the pressure data, thereby obtaining the thickness information of the ice covering the upper part.

[0064] In this embodiment, ice gravity is selected as the physical quantity to be measured. Pressure data related to gravity can be directly collected through a pressure sensor, and gravity data can be obtained based on the pressure data. Then, the thickness of the ice is estimated by the gravity generated by the ice layer on the blade. This method directly links the mass and thickness of the ice, so it can more accurately reflect the actual thickness of the ice layer. Compared with other complex physical quantity monitoring methods, ice gravity detection only needs to measure gravity, and does not need to monitor other physical quantities such as temperature and humidity. This simplifies the detection process, reduces the complexity of the system, and reduces possible sources of error.

[0065] Further, when the pressure sensor on the sensor ring includes a leading edge point sensor 1 and / or a trailing edge point sensor 5, the thickness information of ice above the leading edge point sensor 1 or the trailing edge point sensor 5 is respectively:

[0066]

[0067] Among them, t iis the ice thickness at the leading edge point sensor 1 or the trailing edge point sensor 5 on the i-th sensor ring; F i w is the pressure data measured by the leading edge point sensor 1 or the trailing edge point sensor 5 on the i-th sensor ring; i is the width of the leading edge point sensor 1 or the trailing edge point sensor 5 on the i-th sensor ring, and the width direction is the wingspan direction; l i The length of the leading edge point sensor 1 or the trailing edge point sensor 5 on the i-th sensor ring is perpendicular to the wingspan direction; g is the local gravity acceleration; ρ is the ice density. That is, both the leading edge point sensor 1 and the trailing edge point sensor 5 use the above formula to measure the ice thickness.

[0068] When the pressure sensor on the sensor ring includes a blade point sensor 2, the thickness information of ice above the blade point sensor 2 is specifically:

[0069]

[0070] Among them, t ij is the ice thickness at the jth blade point sensor 2 on the i-th sensor ring; F ij is the pressure data measured by the jth blade point sensor 2 on the i-th sensor ring; w ij is the width of the j-th blade point sensor 2 on the i-th sensor ring, and the width direction is the wingspan direction; l ij The length of the jth blade point sensor 2 on the i-th sensor ring; β ij is the angle between the tangent line of the j-th blade point sensor 2 on the i-th sensor ring and the horizontal line.

[0071] In some specific embodiments, a gravity-thickness conversion submodule may be set in the processor, and the gravity-thickness conversion submodule is used to convert the sensor data into the ice thickness at the location. The module specifically includes two parts: one part is a leading edge point and / or trailing edge point ice thickness calculation module, and the other part is an ice thickness calculation module around the blade element.

[0072] The calculation process of ice thickness at the leading edge point and the trailing edge point is the same. Taking the calculation of ice thickness at the leading edge point as an example, the specific calculation process of the ice thickness calculation module at the leading edge point and / or the trailing edge point is as follows: for a certain wind turbine blade, when the angle with the horizontal line is 0° and the leading edge line is on the top, that is, when the pitch angle of the blade is 0 (in this state, the ice gravity is completely converted into sensor pressure, and there is no force decomposition problem), the reading F of sensor 1 at the i-th leading edge point is i That is the ice pressure on the sensor (ice gravity G i ), calculated according to formula (1):

[0073] G i =ρ·Vi ·g (1)

[0074] Where g is the local gravitational acceleration, in m / s 2 ; ρ is the ice density, unit is kg / m 3 ; V i is the volume of ice covered on the i-th leading edge point sensor 1.

[0075] As attached Figures 4 to 6 As shown in Figure 2. Assume that the ice on each sensor is close to a rectangular parallelepiped, which is called an ice body. The width of each ice body is w i is the width of the sensor ring (the width direction is the wingspan direction), unit is m. Length l i is the length of sensor 1 at the leading edge of the sensor ring, i.e., the dimension along the length direction (the length direction is perpendicular to the wingspan direction, and the length is the length of the semi-ring sensor projected onto the horizontal plane perpendicular to the wingspan direction, such as Figure 6 As shown in the figure, the unit is m. Therefore, according to the volume calculation formula of a cuboid, the volume calculation formula of the ice-covered body at the leading edge of the blade element at the i-th sensor ring can be obtained (2):

[0076] V i =w i ·l i ·t i (2)

[0077] Therefore, formula (3) can be inferred from formula (1) and formula (2), where t i It is the ice thickness at the leading edge of the blade element at the i-th sensor ring, in meters.

[0078]

[0079] The ice thickness calculation module around the blade element is used to calculate the ice thickness at the blade element point sensor 2. The specific calculation process is: for a certain wind turbine blade, when it is in a horizontal position and the pitch angle is 90° (clockwise or counterclockwise) when it is completely stopped, it is easier to calculate the ice thickness at other positions except the leading edge point. In this state, the ice thickness t on the jth blade element point small wireless passive sensor on the i-th annular wireless passive sensor is now explained. ij Formula derivation process.

[0080] As attached Figure 4-Figure 6 As shown. The reading F of the small wireless passive sensor at the jth leaf element on the i-th ring wireless passive sensor ij That is the ice pressure on the sensor (ice gravity G ij ) is calculated according to formula (4):

[0081] F ij =G ij·cosβij=ρ·V ij ·g·cosβ ij (4)

[0082] Where g is the local gravitational acceleration, in m / s 2 ; ρ is ice density, unit: kg / m 3 ; V ij is the ice volume on the i-th leading edge point sensor 1, β ij is the angle between the tangent line at the edge of the blade and the horizontal line, that is, the acute angle. Fig. 9 shown.

[0083] Assume that the ice on each sensor is close to a cuboid. The width w of the ice at the jth blade point on the i-th sensor ring is ij is the sensor ring width, unit m; length l ij is the sensor length in the sensor ring. The length of the blade point sensor 2 can be the dimension along the circumference of the sensor ring, in m. Therefore, according to the rectangular volume calculation formula, the ice volume V at the jth blade point on the i-th sensor ring is ij The calculation is based on formula (5):

[0084] V ij =w ij ·l ij· ·t ij (5)

[0085] Therefore, formula (6) can be inferred from formula (4) and formula (5), where t ij It is the ice thickness at the jth blade point on the ith sensor ring, in meters.

[0086]

[0087] Similarly, the ice thickness at each blade point on the other side is also calculated using the above method.

[0088] The processor is also used to obtain ice-covered airfoil information after ice coating based on the thickness information of ice above the pressure sensor. An ice-covered airfoil calculation module can also be set in the processor, and the ice-covered airfoil calculation module obtains the overall ice-covered airfoil based on the ice thickness and initial airfoil data output by each pressure sensor at the sensor ring position. During the data processing process of this module, it is stipulated that the ice-covered airfoil of the same type of sensor between two adjacent sensor rings changes linearly; and the ice-covered airfoil between two adjacent sensors along the circumferential direction on the same sensor ring can change linearly or be smoothly connected according to the initial airfoil, such as Figure 7 and Figure 8 shown.

[0089] The second embodiment provides an ice coating measurement method for a wind turbine blade. The ice coating measurement method is based on the ice coating measurement device for a wind turbine blade described in any one of the above embodiments. The ice coating measurement method includes:

[0090] Rotate the blade around the hub axis so that the blade is in a horizontal position, and rotate the blade around the blade root axis so that the pressure sensor is located on the upper surface of the blade;

[0091] Collecting pressure data measured by the pressure sensor;

[0092] Ice coating parameter information at the pressure sensor is acquired according to the pressure data.

[0093] During the icing measurement process, the wind turbine can be in a shutdown state, and the blade to be measured is first rotated around the hub to a horizontal position, and then when the pressure sensor includes a leading edge point sensor 1, the blade is rotated around itself, that is, the pitch angle is adjusted so that the leading edge point sensor 1 is located above the blade, and the icing parameter information of the leading edge of the blade element is obtained according to the pressure data measured by the sensor; when the pressure sensor includes a trailing edge point sensor 5, the blade is rotated around itself, that is, the pitch angle is adjusted so that the trailing edge point sensor 5 is located above the blade, and the icing parameter information of the trailing edge of the blade element is obtained according to the pressure data measured by the sensor; when the pressure sensor includes a blade point sensor 2, the blade is rotated around itself, that is, the pitch angle is adjusted so that the side of the blade faces upward, and the icing parameter information of the side of the blade is obtained according to the pressure data measured by the sensor; the two sides of the blade can be measured in turn.

[0094] Specifically, the ice thickness information above the pressure sensor can be obtained according to the pressure data; and the ice-covered airfoil information after ice coating can be further obtained according to the ice thickness information above the pressure sensor.

[0095] The third embodiment provides a wind turbine generator set, which includes blades, and the blades are provided with an ice measurement device for wind turbine blades as described in any of the above embodiments. The wind turbine generator set also includes a driving mechanism for driving the blades to rotate and a power generation mechanism, and other configurations of the wind turbine generator set are well known to those skilled in the art and will not be described in detail here.

[0096] In some specific embodiments, a wind turbine blade ice thickness measurement device and system based on gravity detection are provided, the system mainly consists of two parts: an annular body-attached wireless passive pressure sensor group and a system data processing module. Each annular body-attached wireless passive pressure sensor, i.e., a sensor ring, is composed of at least one of a leading edge point small wireless passive sensor of a blade element, i.e., a leading edge point sensor 1, a trailing edge point small wireless passive sensor of a blade element, i.e., a trailing edge point sensor 5, and a blade element point sensor 2, and an elastic connecting material, i.e., an elastic member, and the system data processing module includes a gravity-thickness conversion submodule and an ice airfoil calculation module.

[0097] The wind turbine blade ice thickness measurement device and system based on gravity detection aims to use a ring-shaped body-attached wireless passive pressure sensor group to measure the ice gravity on the blade surface in a static state, and then obtain the blade ice thickness through the physical properties of ice and airfoil parameter interpolation, and finally obtain the wind turbine blade ice airfoil.

[0098] Specifically, before the time period when blade icing is prone to occur, the sensor ring is installed. Specifically: first adjust the blade position. For safety reasons, rotate the blade around the hub to a vertical state (parallel to the tower). Then put on the sensor ring. Before the icing season begins, put N, for example, 7 wireless passive sensor rings (evenly arranged only in the 0.1L to 0.8L area) from the hub along the blade span direction. In addition to a small wireless passive sensor at the leading edge point (used to measure the ice thickness at the leading edge line) on each sensor ring, 12 blade element point wireless passive sensors (used for ice thickness at other positions, 6 on one side) are also arranged, as shown in the attached figure. Figure 4-Figure 6 shown.

[0099] The number N of annular wireless passive pressure sensors to be arranged and the distance d between the i-th sensor ring (counting from the hub center outward) and the hub center can be determined according to the length L of the blade along the span direction. i , the width w of the i-th sensor ring i (the width of the small wireless passive sensor at the leading edge point and the trailing edge point of the blade element is specified to be the same), the length l of the small wireless passive sensor at the leading edge point of the blade element or the sensor at the trailing edge point 5 in the i-th sensor ring i After determining the sensor layout and adjustable parameters, the sensor readings in each sensor ring will be cleared to zero.

[0100] After the blades are covered with ice, for example, ice measurement can be performed when entering the monitoring time period, specifically:

[0101] Calculate the ice thickness of the leading edge line and / or trailing edge line. Take the leading edge line measurement as an example: adjust the blade position. Stop the wind turbine, rotate the blade to a horizontal position and rotate the blade until the leading edge line is on top, that is, adjust the blade pitch angle to 0°. Figure 1-Figure 3As shown. Calculate the ice thickness of scattered points (front edge points). Read the readings of the small wireless passive sensor at the front edge point on each wireless passive sensor ring, and calculate the ice thickness of the point according to formula (3). Linear interpolation. The ice thickness of the remaining front edge points between two adjacent front edge points where sensors are arranged is calculated by linear interpolation. Arrange the data. Obtain the ice thickness of the entire front edge line. As shown in the attached figure Figure 7 shown.

[0102] Calculate the ice thickness of each blade element except the leading edge point: adjust the blade position. Stop the wind turbine, rotate the blade to a horizontal position and adjust the pitch angle to 90° clockwise, that is, sideways upward; calculate the ice thickness of scattered points (other points on the blade element except the leading edge point), such as Figure 8 As shown. Read the readings of the small wireless passive sensors at the blade points on each wireless passive sensor ring, and calculate the ice thickness of all blade points on the surface according to formula (6). Linear interpolation, the ice thickness of the remaining leading edge points between two adjacent blade points where sensors are arranged is calculated by linear interpolation.

[0103] Adjust the blade position again. Stop the wind turbine and adjust the pitch angle to 90° counterclockwise, with the other side facing up; repeat the above steps of using blade point sensor 2 to measure the thickness (this step is only for the blade points on the other side). Repeat the above steps of using blade point sensor 2 to measure the thickness linear difference (this step is only for the blade points on the other side). Arrange the data. Obtain the complete ice-covered airfoil of each blade element, such as Figure 8 shown.

[0104] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An ice measurement device for wind turbine blades, characterized in that: It comprises a pressure sensor and a processor, wherein the pressure sensor is arranged on the surface of the blade, and the pressure sensor is used to measure the pressure data of ice covering the upper part when the blade rotates around the hub axis to a horizontal position and rotates around the blade root axis until the pressure sensor is located on the upper surface of the blade; The processor is used to collect pressure data measured by the pressure sensor and calculate gravity data of ice covering the upper part according to the pressure data, so as to obtain ice covering parameter information.

2. The ice coating measuring device for wind turbine blades according to claim 1, characterized in that: It also includes an elastic ring sleeved on the surface of the blade, a plurality of the elastic rings are arranged along the span direction of the blade, each of the elastic rings is provided with the pressure sensor to form a sensor ring, and each of the sensor rings is fixed to the surface of the blade by the elastic force of the elastic ring.

3. The ice coating measuring device for wind turbine blades according to claim 2, characterized in that: The pressure sensor on each of the sensor rings includes at least one of a leading edge point sensor, a trailing edge point sensor, and a blade element point sensor; The leading edge point sensor is arranged on the leading edge line of the blade element, and is used to obtain ice coating parameter information at the leading edge line of the blade element; The trailing edge point sensor is arranged on the trailing edge line of the blade element, and is used to obtain ice coating parameter information at the trailing edge line of the blade element; The blade element point sensor is arranged on the side surface of the blade between the blade element leading edge line and the blade element trailing edge line, and is used to obtain ice coating parameter information at the side surface.

4. The ice coating measuring device for wind turbine blades according to claim 2, characterized in that: The elastic ring is formed by detachably connecting two elastic half rings.

5. The ice coating measuring device for wind turbine blades according to claim 4, characterized in that: The pressure sensor is a wireless passive sensor, and the pressure sensor is embedded in the elastic ring; And / or, the two elastic half rings of the elastic ring are connected at the connection point by a hook structure.

6. The ice coating measuring device for wind turbine blades according to any one of claims 1 to 5, characterized in that: The processor is specifically used to obtain thickness information of the ice covering the upper part according to gravity data of the ice covering the upper part and size parameter data of the pressure sensor.

7. The ice coating measuring device for wind turbine blades according to claim 6, characterized in that: The processor is further configured to obtain ice-covered airfoil information after ice coating according to ice thickness information above the pressure sensor.

8. The ice coating measuring device for wind turbine blades according to claim 3, characterized in that: When the pressure sensor on the sensor ring includes a leading edge point sensor and / or a trailing edge point sensor, the thickness information of ice above the leading edge point sensor or the trailing edge point sensor is respectively: Among them, t i is the ice thickness at the leading edge point sensor or trailing edge point sensor on the i-th sensor ring; F i w is the pressure data obtained by the leading edge point sensor or the trailing edge point sensor on the i-th sensor ring; i is the width of the leading edge point sensor or trailing edge point sensor on the i-th sensor ring, and the width direction is the wingspan direction; l i The length of the leading edge point sensor or the trailing edge point sensor on the i-th sensor ring, where the length direction is perpendicular to the wingspan direction; g is the local gravity acceleration; ρ is the ice density; When the pressure sensor on the sensor ring includes a blade point sensor, the thickness information of ice above the blade point sensor is specifically: Among them, t ij is the ice thickness at the jth blade point sensor on the i-th sensor ring; F ij is the pressure data obtained by the j-th blade point sensor on the i-th sensor ring; w ij is the width of the jth blade point sensor on the i-th sensor ring, and the width direction is the span direction; l ij The length of the jth blade point sensor on the i-th sensor ring; β ij is the angle between the tangent line of the j-th blade point sensor on the i-th sensor ring and the horizontal line.

9. A method for measuring ice coverage on wind turbine blades, characterized in that: Based on the ice coating measurement device for wind turbine blades according to any one of claims 1 to 8, the ice coating measurement method comprises: Rotate the blade around the hub axis so that the blade is in a horizontal position, and rotate the blade around the blade root axis so that the pressure sensor is located on the upper surface of the blade; Collecting pressure data measured by the pressure sensor; Ice coating parameter information at the pressure sensor is acquired according to the pressure data.

10. A wind turbine generator set, characterized in that: It comprises a blade, on which is provided an ice coating measurement device for a wind turbine blade according to any one of claims 1 to 8.

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