Wind turbine generator blade damage positioning system
By combining passive impedance sensing components with digital twin models, the problem of sensor deployment affecting the dynamic characteristics of wind turbine blades has been solved, achieving high-precision damage location and low-cost monitoring.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-05
- Publication Date
- 2026-03-27
AI Technical Summary
When existing sensors are deployed on wind turbine blades, dense deployment affects dynamic characteristics, while sparse deployment cannot capture local damage. At the same time, they require independent power supply, are difficult to maintain, and are costly, making it difficult to achieve high-precision damage location.
A passive impedance-type sensing component is adopted. The reader transmits radio frequency signals and receives backscattered signals. The processor extracts signal features and combines them with a digital twin model to determine the damage location. The sensing component is passively powered and lightweight design avoids structural impact.
It achieves centimeter-level precise location of surface damage on wind turbine blades, reducing deployment costs, simplifying maintenance, and avoiding significant changes in weight and aerodynamic shape.
Smart Images
Figure CN121738833A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of wind turbine generators, in particular to a wind turbine generator blade damage positioning system. BACKGROUND
[0002] The wind turbine generator is long-term operated in harsh environment, and the blade is prone to fatigue cracks and other damages, which needs to be monitored by sensors. However, the existing sensors are large in weight and volume, and if densely deployed, the dynamics characteristics of the wind turbine generator blade will be significantly changed, and if sparsely deployed, the local damage cannot be captured. Meanwhile, the sensors need to be independently powered, which is difficult to deploy and maintain, and the cost is high. How to deploy the monitoring network to realize high-precision positioning of the surface damage of the wind turbine generator blade has become a technical problem to be solved at present. SUMMARY
[0003] In view of the above problems, the present application is proposed to provide a wind turbine generator blade damage positioning system which overcomes the above problems or at least partially solves the above problems.
[0004] In order to solve the above problems, in the first aspect of the present application, the present application discloses a wind turbine generator blade damage positioning system, the wind turbine generator blade includes a wind turbine generator blade body and a main load-bearing structure, one end of the wind turbine generator blade body is connected to the main load-bearing structure, the wind turbine generator blade has a corresponding digital twin model, and the system comprises: a reader / writer arranged on the main load-bearing structure, used for transmitting a radio frequency signal and receiving a backscattering signal; a passive impedance type sensing assembly arranged on the wind turbine generator blade body, used for modulating the radio frequency signal into a backscattering signal when detecting a strain signal of the wind turbine generator blade body; a processor electrically connected with the reader / writer, used for extracting a signal feature of the backscattering signal, determining a current spatial coordinate of the passive impedance type sensing assembly according to the signal feature, determining a spatial coordinate offset between the current spatial coordinate and a preset reference spatial coordinate, and determining a damage position of the wind turbine generator blade in the digital twin model based on the spatial coordinate offset.
[0005] Optionally, the passive impedance type sensing assembly includes a strain sensing element, a sensing antenna and a modulation circuit, the modulation circuit is located between the sensing antenna and the strain sensing element, the strain sensing element has an initial circuit parameter, and the strain sensing element is used for modulating the initial circuit parameter into a sensing circuit parameter according to the waveform of the strain signal; the modulation circuit is used for transmitting the sensing circuit parameter to the sensing antenna; The sensing antenna has an initial reflection coefficient. The sensing antenna is used to receive the radio frequency signal. Based on the sensing circuit parameters, the initial reflection coefficient is modulated into a working reflection coefficient. Based on the working reflection coefficient, the radio frequency signal is reflected to form the backscattered signal.
[0006] Optionally, the passive impedance sensing component further includes a flexible substrate electrically connected to the strain sensing element, the sensing antenna, and the modulation circuit.
[0007] Optionally, the initial circuit parameters include an initial capacitance value, the sensing circuit parameters include a sensing capacitance value, and the strain sensing element is a capacitor, used to modulate the initial capacitance value into the sensing capacitance value based on the strain signal.
[0008] Optionally, the initial circuit parameters include an initial resistance value, the sensing circuit parameters include a sensing resistance value, and the strain sensing element is a resistor, used to modulate the initial resistance value into the sensing resistance value based on the strain signal.
[0009] Optionally, there are multiple passive impedance sensing components, which are attached to the wind turbine blade body in an array.
[0010] Optionally, there may be multiple readers, which are distributed across different main load-bearing structures.
[0011] Optionally, the main load-bearing structure includes a root and a web, at least one of the root and the web being connected to the reader / writer.
[0012] Optionally, the signal characteristics include at least one of the following: received signal strength indication, signal phase, arrival time, and resonant frequency.
[0013] Optionally, the processor is configured to, when the wind turbine blades are in a healthy state, establish a mapping database between the reference signal characteristics of the passive impedance sensing component and the reference spatial coordinates; and compare and match the signal characteristics with the mapping database to calculate the current spatial coordinates.
[0014] Optionally, the system further includes a system linkage interface, and the processor is further configured to trigger an external monitor to collect data on the damage location through the system linkage interface after the damage location is determined.
[0015] The embodiments of this application have the following advantages: This application embodiment of the wind turbine blade includes a wind turbine blade body and a main load-bearing structure. One end of the wind turbine blade body is connected to the main load-bearing structure. The wind turbine blade has a corresponding digital twin model. The system includes: a reader / writer disposed on the main load-bearing structure for transmitting radio frequency signals and receiving backscattered signals; a passive impedance sensing component disposed on the wind turbine blade body for modulating the radio frequency signals to form backscattered signals when strain signals of the wind turbine blade body are detected; and a processor electrically connected to the reader / writer for extracting signal features of the backscattered signals, determining the current spatial coordinates of the passive impedance sensing component based on the signal features, determining the spatial coordinate offset between the current spatial coordinates and preset reference spatial coordinates, and determining the damage location of the wind turbine blade in the digital twin model based on the spatial coordinate offset. The reader transmits radio frequency (RF) signals, while the passive impedance sensing component modulates the RF signal into a backscattered signal when strain signals are detected on the wind turbine blade. The reader receives the backscattered signal, and the passive impedance sensing component is wirelessly powered by the reader, fundamentally solving the deployment and maintenance problems of traditional sensors that require independent power supplies. Simultaneously, the passive impedance sensing component can be simplified into a lightweight thin-film circuit, resulting in low cost. This allows for high-density deployment without significantly increasing the weight of the wind turbine blade or altering its aerodynamic shape, thus balancing monitoring resolution and structural impact. Based on this, the processor, electrically connected to the reader, can extract the signal characteristics of the backscattered signal and calculate its current spatial coordinates. Then, combined with preset reference spatial coordinates, it directly calculates the spatial coordinate offset reflecting structural deformation. Based on the spatial coordinate offset, the damage location is determined in the digital twin model of the wind turbine blade, achieving centimeter-level precise positioning of surface damage on the wind turbine blade. Attached Figure Description
[0016] Figure 1 This is a structural block diagram of a wind turbine blade damage location system according to this application.
[0017] Explanation of reference numerals in the attached figures: 100-reader / writer, 200-passive impedance sensing component, 210-strain sensing element, 220-sensing antenna, 230-modulation circuit, 300-processor, 400-system linkage interface. Detailed Implementation
[0018] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0019] Figure 1This diagram illustrates a structural block diagram of a wind turbine blade damage location system according to this application. The wind turbine blade includes a blade body and a main load-bearing structure. One end of the blade body is connected to the main load-bearing structure. The wind turbine blade has a corresponding digital twin model. The system includes: The reader 100 is disposed on the main load-bearing structure and is used to transmit radio frequency signals and receive backscattered signals. A passive impedance sensing component 200 is disposed on the wind turbine blade body and is used to modulate the radio frequency signal into a backscattered signal when the strain signal of the wind turbine blade body is detected. The processor 300, electrically connected to the reader 100, is used to extract the signal characteristics of the backscattered signal, determine the current spatial coordinates of the passive impedance sensing component based on the signal characteristics, determine the spatial coordinate offset between the current spatial coordinates and the preset reference spatial coordinates, and determine the damage location of the wind turbine blade in the digital twin model based on the spatial coordinate offset.
[0020] Specifically, multiple readers 100 can be installed on the main load-bearing structure of the wind turbine blade, such as the root and web of the blade, forming a reader 100 network. This network maintains stability during monitoring, ensuring no relative displacement between the readers 100 and the wind turbine blade, thus guaranteeing that the radio frequency signals emitted by the readers 100 stably cover the entire monitoring area and provide continuous wireless power. Furthermore, multiple passive impedance sensing components 200 can be deployed on the surface of the wind turbine blade, such as the leading edge, trailing edge, and cap, forming a highly dense sensing array. When excited by a strain signal, the passive impedance sensing component 200 modulates the radio frequency signal to generate a backscattered signal, which the readers 100 can receive.
[0021] Furthermore, the wind turbine blade damage location system also includes a processor 300, which is electrically connected to the reader 100. After the reader 100 receives these backscattered signals, the processor 300 can extract the signal features from the backscattered signals and, using radio frequency positioning algorithms (such as fingerprint positioning algorithms), can accurately locate the area where damage or abnormal strain signals have occurred. For example, it can determine the current spatial coordinates of the passive impedance sensing component 200 based on the signal features, determine the spatial coordinate offset based on the current spatial coordinates and the preset reference spatial coordinates, and determine the damage location in the digital twin model of the wind turbine blade based on the spatial coordinate offset.
[0022] In another wind turbine blade damage location system of this application, the wind turbine blade includes a blade body and a main load-bearing structure. One end of the blade body is connected to the main load-bearing structure. The wind turbine blade has a corresponding digital twin model. A reader 100 is fixedly installed on the main load-bearing structure, such as the root or web of the wind turbine blade. The reader 100 can realize ultra-high frequency radio frequency identification (i.e., UHF RFID). The reader 100 can integrate transmitting and receiving antennas respectively. The core function of the reader 100 is to transmit radio frequency signals of a specific frequency and receive backscattered signals reflected back from passive impedance sensing components 200. The passive impedance sensing components 200 are mainly set on the surface areas of the wind turbine blade that need to be monitored (such as the leading edge, trailing edge, and beam cap), and can be deployed at a high density. When the radio frequency signal transmitted by the reader 100 illuminates these passive impedance sensing components 200, they are activated. When a wind turbine blade generates a strain signal due to internal cracks or localized damage, this strain signal can cause a change in the impedance value of the passive impedance sensing component 200. This, in turn, modulates the reflection characteristics of the sensing antenna 220 inside the passive impedance sensing component 200 in real time, thereby changing the signal characteristics (such as the received signal strength indication, signal phase, arrival time, and resonant frequency) of the backscattered signal reflected back by the passive impedance sensing component 200. In other words, the strain signal at that location can be reflected through the signal characteristics. Furthermore, the reader 100 is electrically connected to the processor 300, which can transmit all the backscattered signals received from the passive impedance sensing components 200 to the processor 300. The processor 300 can extract the signal characteristics of the backscattered signals and associate them with the preset reference spatial coordinates of each passive impedance sensing component 200 in the digital twin model of the wind turbine blade, thereby establishing a mapping database. Then, when a strain signal occurs, the spatial coordinate offset can be obtained by calculating the current spatial coordinates of the passive impedance sensing component 200 and combining them with the preset reference spatial coordinates. Finally, the processor 300 can map this coordinate offset to the digital twin model of the wind turbine blade to accurately locate the damage location.
[0023] In this embodiment, a reader 100 is installed on the main load-bearing structure of a wind turbine blade and is used to transmit radio frequency signals. A passive impedance sensing component 200 is installed on the surface of the wind turbine blade and is used to detect strain signals on the surface. Under the excitation of the strain signal, the radio frequency signal is modulated to form a backscattered signal. The reader 100 is also used to receive the backscattered signal. A processor 300 is electrically connected to the reader 100 and is used to extract signal features, determine the current spatial coordinates of the passive impedance sensing component 200 based on the signal features, determine the spatial coordinate offset based on the current spatial coordinates and the preset reference spatial coordinates, and determine the damage location in the digital twin model of the wind turbine blade based on the spatial coordinate offset. Specifically, fixing the reader 100 to the main load-bearing structure of the wind turbine blade provides a stable installation foundation. This ensures the absolute position stability of the reader 100, providing a reference for subsequent positioning, which is a prerequisite for the system to achieve accurate damage location. Secondly, it ensures reliable wireless power supply and signal interaction between the reader / writer 100 and the network of passive impedance sensing components 200 on the wind turbine blade surface. The passive impedance sensing components 200 can detect surface strain signals. When excited by strain signals, they can modulate radio frequency signals to form backscattered signals. This wireless power supply avoids wiring and battery replacement, facilitating deployment and maintenance. Furthermore, the functionality of the passive impedance sensing components 200 is simplified, including only sensing and signal reflection functions, without data processing capabilities. This allows for the fabrication of lightweight thin-film circuits, resulting in low cost. High-density deployment does not significantly increase the weight of the wind turbine blades or alter their aerodynamic shape, thus balancing monitoring resolution and structural impact. Simultaneously, the passive impedance sensing components 200 can directly convert strain signals into signal characteristics, enabling the system to have high sensitivity to minute strain signals. In addition, the system includes a processor 300, which can be electrically connected to the reader 100. This processor extracts the signal characteristics of the backscattered signal and determines the current spatial coordinates of the passive impedance sensing component 200 based on these characteristics. It then determines the spatial coordinate offset based on the current spatial coordinates and a preset reference spatial coordinate, and uses this offset to pinpoint the damage location in the digital twin model of the wind turbine blade. This allows for the correlation between abnormal signal characteristics and the spatial location of structural deformation, providing a more intuitive view of the damage location and outline in the digital twin model. This achieves centimeter-level precise localization of surface damage on wind turbine blades.
[0024] In an optional embodiment of this application, the passive impedance sensing component 200 includes a strain sensing element 210, a sensing antenna 220, and a modulation circuit 230, wherein the modulation circuit 230 is located between the sensing antenna 220 and the strain sensing element 210. The strain sensing element 210 has initial circuit parameters, and the strain sensing element 210 is used to modulate the initial circuit parameters into sensing circuit parameters according to the waveform of the strain signal. The modulation circuit 230 is used to transmit the sensing circuit parameters to the sensing antenna 220; The sensing antenna 220 has an initial reflection coefficient. The sensing antenna 220 is used to receive the radio frequency signal. Based on the sensing circuit parameters, the initial reflection coefficient is modulated into a working reflection coefficient. Based on the working reflection coefficient, the radio frequency signal is reflected to form the backscattered signal.
[0025] Specifically, to convert the waveform changes of the strain signal from the wind turbine blades into signal characteristic changes, a strain sensing element 210, a modulation circuit 230, and a sensing antenna 220 are internally arranged in the passive impedance sensing component 200. When a small strain signal waveform occurs on the wind turbine blades, the initial circuit parameters of the strain sensing element 210 can be changed, modulating the initial circuit parameters into sensing circuit parameters. Simultaneously, the modulation circuit 230 serves as the terminal load of the sensing antenna 220. Under the radio frequency signal transmitted by the reader 100, the reflection coefficient of the sensing antenna 220 can be determined by both its load impedance (i.e., the sensing circuit parameters) and the characteristic impedance of the sensing antenna 220.
[0026] The formula for calculating the reflection coefficient of sensor antenna 220 is as follows: (1) in The reflection coefficient; The load impedance; For terminal load.
[0027] For example, after the waveform of the strain signal changes, the initial circuit parameters of the strain sensing element 210 can be altered, thereby changing the load impedance of the modulation circuit 230. This leads to a higher reflectance. The signal characteristics change. Thus, when the passive impedance sensing component 200 is excited by a strain signal, it modulates the radio frequency signal, and consequently, the backscattered signal also changes; that is, the strain signal directly modulates the radio frequency signal. Those skilled in the art can set the type of strain sensing element 210 according to actual needs; this application embodiment does not specifically limit this. For example, the strain sensing element 210 can be a capacitor or a resistor.
[0028] Furthermore, the modulation circuit 230 can be disposed between the sensing antenna 220 and the strain sensing element 210. It can transmit sensing circuit parameters to the sensing antenna 220. The sensing antenna 220 has an initial reflection coefficient and is used to receive radio frequency signals. Based on the sensing circuit parameters, the initial reflection coefficient is modulated into a working reflection coefficient. Based on the working reflection coefficient, the radio frequency signal is reflected to form a backscattered signal. The strain sensing element 210 is highly sensitive to changes in the waveform of the strain signal. The modulation circuit 230, located between the sensing antenna 220 and the strain sensing element 210, can change the initial circuit parameters of the strain sensing element 210 based on the waveform of the strain signal, thereby converting this into the load impedance of the modulation circuit 230. Furthermore, changes in the circuit parameters can directly cause a shift in the resonant frequency of the modulation circuit 230. As the terminal load of the sensing antenna 220, the load impedance of the modulation circuit 230 will also change at the operating frequency. According to formula (1), the load impedance directly determines the reflection coefficient of the sensing antenna 220. Therefore, changes in the waveform of the strain signal can cause changes in the impedance value, thereby modulating at least one signal characteristic of the radio frequency signal. Those skilled in the art can determine the size parameters of the sensing antenna 220 according to actual needs, and the embodiments of this application do not impose specific limitations on this.
[0029] This application embodiment of the passive impedance sensing component 200 includes a strain sensing element 210, a sensing antenna 220, and a modulation circuit 230. The modulation circuit 230 is located between the sensing antenna 220 and the strain sensing element 210. The strain sensing element 210 has initial circuit parameters and is used to modulate the initial circuit parameters into sensing circuit parameters according to the waveform of the strain signal. The modulation circuit 230 is used to transmit the sensing circuit parameters to the sensing antenna 220. The sensing antenna 220 has an initial reflection coefficient and is used to receive radio frequency signals. Based on the sensing circuit parameters, the initial reflection coefficient is modulated into a working reflection coefficient, and the radio frequency signal is reflected based on the working reflection coefficient to form a backscattered signal. This passive impedance sensing component can establish a "strain signal-circuit parameter-signal characteristic" conversion channel through the sensing antenna 220, the modulation circuit 230, and the strain sensing element 210. First, the modulation circuit 230 can be positioned between the sensing antenna 220 and the strain sensing element 210. This ensures that the signal characteristics can be modulated as quickly as possible after the circuit parameters are changed according to the waveform of the strain signal, thereby improving the conversion sensitivity from strain signal to signal characteristics. Furthermore, positioning the modulation circuit 230 between the sensing antenna 220 and the strain sensing element 210 creates a compact spatial relationship, enabling the integration of sensing, modulation, and reflection functions onto a single substrate. This not only achieves weight reduction for the passive impedance sensing component 200 but also lowers deployment costs.
[0030] In an optional embodiment of this application, the passive impedance sensing component 200 further includes a flexible substrate electrically connected to the strain sensing element 210, the sensing antenna 220, and the modulation circuit 230.
[0031] To achieve the integration of the strain sensing element 210, the sensing antenna 220, and the modulation circuit 230, the passive impedance sensing component 200 may further include a flexible substrate. This allows the strain sensing element 210, the modulation circuit 230, and the sensing antenna 220 to be fabricated on the flexible substrate. Those skilled in the art can determine the component fabrication process according to actual needs, and this application embodiment does not impose specific limitations on this. For example, the components can be integrated through photolithography and etching steps. The flexible substrate can also be a flexible printed circuit board. Furthermore, the strain sensing element 210, the sensing antenna 220, and the modulation circuit 230 are not discretely mounted, but are directly connected through conductive lines fabricated on the flexible substrate. Therefore, the strain sensing element 210, the modulation circuit 230, and the sensing antenna 220 can achieve a reliable electrical connection. Those skilled in the art can determine the size parameters and material of the flexible substrate according to actual needs, and this application embodiment does not impose specific limitations on this. For example, a total thickness of less than 0.5 mm and a weight of 1-2 grams can be achieved using materials such as polyimide.
[0032] The passive impedance sensing component 200 in this embodiment also includes a flexible substrate, which is electrically connected to the strain sensing element 210, the sensing antenna 220, and the modulation circuit 230. Using a flexible substrate allows it to serve as an integrated substrate, enabling the electrical connection of the strain sensing element 210, the sensing antenna 220, and the modulation circuit 230 through internal wiring. Firstly, the flexible substrate achieves structural lightweighting, resulting in a very low added mass for the entire passive impedance sensing component 200. This fundamentally ensures that high-density deployment will not significantly alter the weight and aerodynamic shape of the wind turbine blades, thus balancing monitoring resolution and structural impact. Secondly, the flexible substrate allows the passive impedance sensing component 200 to fit more closely to the wind turbine blade body with its complex curvature. Simultaneously, the integrated flexible substrate can be connected to the strain sensing element 210, the sensing antenna 220, and the modulation circuit 230 via conductive lines, eliminating traditional welding methods and improving the reliability of the passive impedance sensing component 200 under harsh environments such as long-term vibration. Meanwhile, by utilizing flexible substrates, mass production can be achieved, and the cost of a single passive impedance sensing component 200 is low, enabling the deployment of a dense sensing network consisting of hundreds of passive impedance sensing components 200 on the wind turbine blade body.
[0033] In an optional embodiment of this application, the initial circuit parameters include an initial capacitance value, the sensing circuit parameters include a sensing capacitance value, and the strain sensing element 210 is a capacitor used to modulate the initial capacitance value into the sensing capacitance value based on the strain signal.
[0034] Specifically, in order to achieve real-time monitoring of the strain signal of the wind turbine blades, the strain sensing element 210 in this system can be configured as a capacitor. The capacitor is used to modulate the initial capacitance value into a sensing capacitance value based on the strain signal, thereby modulating the signal characteristics. The resistor is used to convert the strain signal into a resistance value, thereby modulating the radio frequency signal.
[0035] For example, the capacitor can be an interdigital capacitor. This interdigital capacitor is fabricated on a flexible substrate, and its sensing capacitance value is highly sensitive to strain signals within the plane of the flexible substrate, as shown in the following formula: (2) in This is the value of the sensing capacitance; This is the initial capacitance value; This is the sensitivity coefficient; This is a strain signal.
[0036] Based on the above formula (2), it can be concluded that the strain signal of the wind turbine blade changes linearly with the value of the sensing capacitance. This capacitor, together with an integrated inductor, constitutes the modulation circuit 230. Its resonant frequency can be referenced... The following formula: (3) in The resonant frequency; Pi; For integrated inductors; This is the value of the sensing capacitance; This is the initial capacitance value.
[0037] Based on the above formula (3), the relationship between the sensing capacitance value and the resonant frequency can be obtained. The modulation circuit 230 can be used as the load of the sensing antenna 220, and can be selected in the UHF band (such as 920-925MHz). This operating frequency band has good penetration in composite materials and can meet the positioning accuracy requirements. Those skilled in the art can also determine the operating frequency band according to actual needs, and this application embodiment does not make specific limitations in this regard. In addition, its load impedance is extremely sensitive to the resonant frequency shift at the operating frequency of the reader 100, thereby changing the reflection coefficient of the sensing antenna 220. Therefore, the change in capacitance value ultimately modulates the signal characteristics of the radio frequency signal through the modulation circuit 230, for example, it can be a shift in the resonant frequency. Those skilled in the art can also determine the type of capacitor according to actual needs, and this application embodiment does not make specific limitations in this regard.
[0038] The initial circuit parameters in this embodiment include an initial capacitance value, and the sensing circuit parameters include a sensing capacitance value. The strain sensing element 210 is a capacitor, used to modulate the initial capacitance value into a sensing capacitance value based on the strain signal. When the strain sensing element 210 is a capacitor, the initial capacitance value is modulated into a sensing capacitance value based on the strain signal. The sensing capacitance value is used to modulate the radio frequency signal, which can directly convert mechanical deformation into a change in capacitance value, resulting in a more sensitive response.
[0039] In an optional embodiment of this application, the initial circuit parameters include an initial resistance value, the sensing circuit parameters include a sensing resistance value, and the strain sensing element 210 is a resistor used to modulate the initial resistance value into the sensing resistance value based on the strain signal.
[0040] Furthermore, when the strain sensing element 210 is a resistor, its resistance value changes linearly with the strain signal. The initial resistance value can be modulated into a sensing resistance value based on the strain signal. This resistor can be directly used as a terminating load resistor of the sensing antenna 220 or as a component in the modulation circuit 230. Changes in its resistance value can directly alter the load impedance of the sensing antenna 220, thereby changing the reflection coefficient of the sensing antenna 220. This also enables modulation of the signal characteristics of the radio frequency signal. Those skilled in the art can also determine the type of resistor according to actual needs; this application does not specifically limit this.
[0041] The initial circuit parameters in this embodiment also include an initial resistance value, and the sensing circuit parameters also include a sensing resistance value. The strain sensing element 210 is a resistor, used to modulate the initial resistance value into a sensing resistance value based on the strain signal. When the strain sensing element 210 is a resistor, the initial resistance value is modulated into a sensing resistance value based on the strain signal. The sensing resistance value is used to modulate the radio frequency signal, which can directly convert mechanical deformation into a change in resistance value, resulting in higher measurement accuracy.
[0042] In an optional embodiment of this application, there are multiple passive impedance sensing components 200, which are attached to the wind turbine blade body in an array.
[0043] To achieve "dense" monitoring of wind turbine blades, multiple passive impedance sensing components 200 need to be deployed. For example, these components can be arrayed across the entire blade body or key monitoring areas (such as the leading and trailing edges). The array consists of hundreds of independent and identical passive impedance sensing components 200. The distribution of these components can be tailored to the aerodynamic shape and structural risks of the wind turbine blade. For instance, high-density deployment can be used in high-risk areas (such as the easily corroded leading edge and the blade cap), while low-density deployment can be used in low-risk areas. Those skilled in the art can also determine the deployment spacing of the passive impedance sensing components 200 according to actual needs; this embodiment does not specifically limit this. For example, a high-density deployment spacing can be 10cm × 10cm, while a low-density deployment spacing can be 20cm × 30cm, thus improving resource utilization. In practical applications, each passive impedance sensing component 200 can be fabricated as a flexible substrate, allowing it to be directly attached to the wind turbine blade body.
[0044] In this embodiment, multiple passive impedance sensing components 200 are used, distributed in an array and attached to the wind turbine blade body. Deploying multiple passive impedance sensing components 200 forms a dense sensing network, enabling the detection of concentrated local strain signals and micro-cracks, thus achieving early warning of wind turbine blade damage. Secondly, by distributing multiple passive impedance sensing components 200 in an array on the wind turbine blade body, a complete mapping database of the signal characteristics of the passive impedance sensing components 200 and preset reference spatial coordinates can be generated, providing a data foundation for subsequent damage localization. Furthermore, the cost of a single passive impedance sensing component 200 is extremely low. Simultaneously, its wireless, passive, and lightweight characteristics ensure that high-density deployment does not significantly increase the weight of the wind turbine blade or alter its aerodynamic shape, thereby balancing monitoring resolution and structural impact.
[0045] In one optional embodiment of this application, the number of readers 100 is multiple, and the readers are distributed in different main load-bearing structures.
[0046] Specifically, the number of readers 100 can be set to multiple, mainly fixedly installed at different main load-bearing structural positions on the wind turbine blades. Each reader 100 includes a transmitting and receiving antenna, which can transmit radio frequency signals through the transmitting antenna and receive backscattered signals through the receiving antenna, thus constructing a reader 100 network that can provide multiple spatial observation points. When the readers 100 are working, they can transmit radio frequency signals synchronously or in a time-division manner to excite the passive impedance sensing components 200 of the entire wind turbine blade body. In addition, when the passive impedance sensing components 200 reflect backscattered signals, the distributed readers 100 can synchronously receive backscattered signals from the same passive impedance sensing component 200 from different spatial observation points, enabling the system to simultaneously collect multiple sets of signal characteristics from the same passive impedance sensing component 200, thereby providing a data basis for subsequent damage location. Those skilled in the art can choose the location of the readers 100 according to actual needs, and this application embodiment does not specifically limit this.
[0047] In this embodiment, multiple readers 100 are distributed across the main load-bearing structures of different wind turbine blades. By constructing a network of readers 100, multiple stable spatial observation points are provided for the system. This allows the backscattered signals reflected by each passive impedance sensing component 200 to be received by different spatial observation points, enabling the direct acquisition of multiple sets of signal characteristics from the same passive impedance sensing component 200. The network of multiple readers 100 provides multi-dimensional raw data, allowing the processor 300 to construct a mapping database of "signal characteristics of passive impedance sensing components 200 and preset reference spatial coordinates". Based on this, by matching the real-time current spatial position with the preset reference spatial coordinates in the mapping database, centimeter-level precision determination of surface damage to wind turbine blades can be achieved.
[0048] In an optional embodiment of this application, the main load-bearing structure includes a root and a web, at least one of the root and the web being connected to the reader 100.
[0049] For example, the reader 100 can be fixedly installed on the root and web of the wind turbine blade, and connected to its transmitting and receiving antennas via coaxial cables. Therefore, the transmitting and receiving antennas are also fixed on the main load-bearing structures, because the main load-bearing structures are the core components of the wind turbine blades that bear the load. The root mainly bears huge torque and bending moment, while the web mainly provides shear strength. Installing the reader 100 on these two main load-bearing structures can provide a stable installation foundation for the reader 100.
[0050] The wind turbine blades in this embodiment include a root and a web, with at least one of the root and web connected to a reader 100. Firstly, the reader 100 can be installed on the main load-bearing structures such as the root and web, achieving a stable mechanical installation and effectively resisting stress from the rotation and vibration of the wind turbine blades, preventing the reader 100 from loosening or being damaged. Secondly, the reader 100 located on the main load-bearing structure has the shortest antenna and coaxial cable wiring, thus avoiding the signal attenuation risk caused by wiring on non-load-bearing structures. Installing the reader 100 on the main load-bearing structures such as the root and web provides a stable wireless power transmission and signal acquisition point for the entire dense network of passive impedance sensing components 200, which is the physical basis for the maintenance-free operation of the passive impedance sensing component 200 network throughout the entire life cycle of the wind turbine blade.
[0051] In an optional embodiment of this application, the signal characteristics include at least one of the following: received signal strength indication, signal phase, arrival time, and resonant frequency.
[0052] Furthermore, the reader 100 can periodically transmit radio frequency signals to provide wireless power excitation for the passive impedance sensor network 200. Simultaneously, the reader 100 receives and analyzes the backscattered signals reflected from all passive impedance sensor networks 200. Specifically, the processor 300 extracts the signal characteristics of the backscattered signal from each passive impedance sensor 200, including at least the Received Signal Strength Indication (RSSI), signal phase, Time of Arrival (TOA), and resonant frequency. Among them, the received signal strength indicator is mainly used to characterize the attenuation of the radio frequency signal on the propagation path. Its change can reflect the relative change in the distance between the passive impedance sensing component 200 and the reader 100, and can also reflect the abrupt change in material properties (such as delamination and cracks) on the signal propagation path. The signal phase is more sensitive to the change in the distance between the passive impedance sensing component 200 and the reader 100. The core function of the signal phase is to provide relative displacement information. The arrival time can characterize the absolute time delay of the radio frequency signal from the reader 100 to the passive impedance sensing component 200 and back. The core function of the arrival time is to calculate the absolute distance between the passive impedance sensing component 200 and multiple readers 100. The resonant frequency is determined by the modulation circuit 230 of the passive impedance sensing component 200 itself. The resonant frequency can directly represent the local state (such as strain signal and temperature) change on the surface of the wind turbine blade. Through multi-dimensional signal feature extraction, the local strain signal on the surface of the wind turbine blade can be directly captured by the offset value of the real-time resonant frequency. Building upon this foundation, it is possible to further integrate multi-dimensional signal features such as signal strength index (RSSI), signal phase, and time of arrival (TOA), and determine the current position coordinates of the passive impedance sensing component 200 based on positioning algorithms such as fingerprint positioning or differential arrival methods. Furthermore, by combining these with preset reference spatial coordinates, the spatial coordinate offset reflecting structural deformation is directly calculated. Based on this spatial coordinate offset, the damage location is determined in the digital twin model of the wind turbine blade, thus achieving centimeter-level precise positioning of surface damage on the wind turbine blade.
[0053] The signal features in this application embodiment include at least one of the following: received signal strength indication, signal phase, arrival time, and resonant frequency. These signal features, such as received signal strength indication, signal phase, arrival time, and resonant frequency, can be extracted from the backscattered signal. First, the shift in resonant frequency can determine the local state changes on the wind turbine blade surface in real time. Second, simultaneously, based on the received signal strength indication, signal phase, and arrival time, fingerprint positioning algorithms or differential arrival methods can be used to directly locate the detected signal feature anomalies to the spatial coordinates of the wind turbine blade structure. Utilizing multiple signal features can improve the system's positioning reliability in complex environments.
[0054] In an optional embodiment of this application, the processor 300 is configured to establish a mapping database between the reference signal characteristics of the passive impedance sensing component 200 and the reference spatial coordinates when the wind turbine blades are in a healthy state; and compare and match the signal characteristics with the mapping database to calculate the current spatial coordinates.
[0055] In practical applications, the processor 300 is electrically connected to the reader 100 network, allowing the reader 100 network to scan the passive impedance sensing component 200 network when the wind turbine blades are in a healthy state. The processor 300 can acquire the reference signal characteristics of each passive impedance sensing component 200, which may include Received Signal Strength Indicator (RSSI), signal phase, Time of Arrival (TOA), and resonant frequency. The processor 300 associates these signal characteristics with the preset reference spatial coordinates of each passive impedance sensing component 200 in the digital twin model of the wind turbine blade, establishing a mapping database of "signal characteristics of passive impedance sensing components 200 and reference spatial coordinates". During actual monitoring, the processor 300 continuously acquires the real-time signal characteristics of each passive impedance sensing component 200 and compares these real-time signal characteristics with the signal characteristics in the mapping database. Specifically, it first compares the real-time resonant frequency with the reference resonant frequency; if they are inconsistent, the passive impedance sensing component 200 is identified as an anomaly. Then, for the anomalous tags, the processor 300 can utilize its real-time acquired received signal strength indication (RSSI), signal phase, and time of arrival (TOA) and other multi-dimensional signal features to perform pattern matching and optimization calculations with the historical fingerprints of the passive impedance sensing component 200 stored in the mapping database under different preset reference spatial coordinates. For example, by using the weighted k-nearest neighbor (WKNN) method or the time difference of arrival (TDOA) method for optimization calculation, the current spatial coordinates of the passive impedance sensing component 200 after displacement can be calculated. The processor 300 combines the calculated current spatial coordinates with the preset reference spatial coordinates to determine the spatial coordinate offset, and then, by combining the resonant frequency offset, can locate the damage point on the digital twin model. In addition, spatial clustering analysis can be performed on the location results of multiple adjacent anomalous tags to further delineate the contour of the damage area.
[0056] In this embodiment, the processor 300 establishes a mapping database between the reference signal characteristics of the passive impedance sensing component 200 and preset reference spatial coordinates when the wind turbine blades are in a healthy state. The signal characteristics are compared and matched with the mapping database to calculate the current spatial coordinates. By establishing the mapping database, a unique preset reference spatial coordinate is established for each passive impedance sensing component 200 in a healthy state. Furthermore, during real-time monitoring, the current spatial coordinates of the passive impedance sensing component 200 are calculated by performing pattern matching and optimization calculations between the real-time signal characteristics and the mapping database, thereby achieving centimeter-level precise positioning of surface damage on the wind turbine blades.
[0057] In an optional embodiment of this application, the system further includes a system linkage interface 400, and the processor 300 is further configured to trigger an external monitor to collect data on the damage location through the system linkage interface 400 after determining the damage location.
[0058] Furthermore, the wind turbine blade damage location system may also include a system linkage interface 400. In the processor 300, after calculating the current spatial coordinates of the damage through comparison and matching, and further determining the damage location, if the severity exceeds a preset threshold, the processor 300 can generate a trigger command, which at least includes the current spatial coordinates. Thus, the processor 300 can send this trigger command to one or more more powerful dedicated monitors via the system linkage interface 400. These dedicated monitors typically possess high-precision sensing capabilities (such as ultrasonic probes and acoustic emission sensors), but their power consumption and cost are high, so they are usually in a dormant state to save energy. Upon receiving the trigger command from the system processor 300, these external dedicated monitors are awakened and can adjust their monitoring points according to the current location coordinate information in the trigger command. For example, they can activate the sensor cluster closest to the current location coordinates to initiate high-resolution data acquisition of the damage location and its surrounding area.
[0059] The wind turbine blade damage location system of this application embodiment also includes a system linkage interface 400. The processor 300 is further used to trigger an external monitor to collect data on the damage location after determining the damage location via the system linkage interface 400. The wind turbine blade damage location system also includes a system linkage interface 400. After determining the damage location, the processor 300 can trigger an external monitor to perform high-precision data collection on the damaged area via the system linkage interface 400. The passive impedance-type sensor component 200 network can achieve full-coverage monitoring of wind turbine blades at low cost, completing large-scale surveys and precise damage location. Once damage is detected, the system can wake up the external monitor via the system linkage interface 400 to conduct detailed data collection at that location. This design avoids the cost problem of deploying expensive, high-performance sensors on all wind turbine blades, while ensuring timely initiation of further detection upon damage detection to obtain detailed data on the damaged area, thereby improving the overall practicality and economy of the system.
[0060] This application embodiment of the wind turbine blade includes a wind turbine blade body and a main load-bearing structure. One end of the wind turbine blade body is connected to the main load-bearing structure. The wind turbine blade has a corresponding digital twin model. The system includes: a reader 100, disposed on the main load-bearing structure, for transmitting radio frequency signals and receiving backscattered signals; a passive impedance sensing component 200, disposed on the wind turbine blade body, for modulating the radio frequency signal to form a backscattered signal when a strain signal of the wind turbine blade body is detected; and a processor 300, electrically connected to the reader 100, for extracting the signal characteristics of the backscattered signal, determining the current spatial coordinates of the passive impedance sensing component 200 based on the signal characteristics, determining the spatial coordinate offset between the current spatial coordinates and the preset reference spatial coordinates, and determining the damage location of the wind turbine blade in the digital twin model based on the spatial coordinate offset. The passive impedance sensing component 200 includes a strain sensing element 210, a sensing antenna 220, and a modulation circuit 230. The modulation circuit 230 is located between the sensing antenna 220 and the strain sensing element 210. The strain sensing element 210 has initial circuit parameters and is used to modulate the initial circuit parameters into sensing circuit parameters according to the waveform of the strain signal. The modulation circuit 230 is used to transmit the sensing circuit parameters to the sensing antenna 220. The sensing antenna 220 has an initial reflection coefficient and is used to receive radio frequency signals. Based on the sensing circuit parameters, the initial reflection coefficient is modulated into a working reflection coefficient, and the radio frequency signal is reflected based on the working reflection coefficient to form a backscattered signal. The passive impedance sensing component 200 also includes a flexible substrate electrically connected to the strain sensing element 210, the sensing antenna 220, and the modulation circuit 230. The initial circuit parameters include an initial capacitance value, and the sensing circuit parameters include a sensing capacitance value. The strain sensing element 210 is a capacitor used to modulate the initial capacitance value into a sensing capacitance value based on the strain signal. The initial circuit parameters also include an initial resistance value, and the sensing circuit parameters also include a sensing resistance value. The strain sensing element 210 is a resistor used to modulate the initial resistance value into a sensing resistance value based on the strain signal. Multiple passive impedance sensing components 200 are present, and these components are attached to the wind turbine blade body in an array. Multiple readers 100 are present, and they are distributed across different main load-bearing structures. The main load-bearing structure includes a root and a web, and at least one of the root and the web is connected to a reader 100. The signal characteristics include at least one of the following: received signal strength indication, signal phase, arrival time, and resonant frequency. The processor 300 is used to establish a mapping database of reference signal characteristics and reference spatial coordinates of the passive impedance sensing components 200 when the wind turbine blade is in a healthy state; and to compare and match the signal characteristics with the mapping database to calculate the current spatial coordinates.The system also includes a system linkage interface 400. The processor 300 is used to trigger an external monitor to collect data on the damage location after the damage location is determined. Firstly, by using a passive impedance-type sensing component 200 integrated into a flexible substrate, the passive impedance-type sensing component 200 is made lightweight and low-cost. This allows for high-density deployment without significantly increasing the weight of the wind turbine blades or altering their aerodynamic shape, thus balancing monitoring resolution and structural impact. Furthermore, it requires no power supply and is maintenance-free. Secondly, placing the reader 100 at the blade root or web, or other main load-bearing structures, ensures the stability of the reader 100. Thirdly, by extracting multi-dimensional signal characteristics such as the intensity indication, signal phase, arrival time, and resonant frequency of the backscattered signal reflected by the passive impedance-type sensing component 200, and comparing them with a mapping database of reference signal characteristics established in a healthy state and preset reference spatial coordinates, the current spatial coordinates are calculated, thereby achieving centimeter-level precise location of the damage. Finally, the system linkage interface 400 can also trigger an external monitor to collect detailed data on the damage point after the damage is located. This design avoids the cost burden of arranging expensive high-performance sensors throughout the entire wind turbine blade range, and can also perform high-precision detection of the damaged area through an external monitor when damage is detected, thereby improving the overall practicality and economy of the system.
[0061] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.
[0062] The above provides a detailed description of the wind turbine blade damage location system provided in this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. A wind turbine blade damage location system, characterized in that, The wind turbine blade includes a blade body and a main load-bearing structure. One end of the blade body is connected to the main load-bearing structure. The wind turbine blade has a corresponding digital twin model. The system includes: A reader / writer, disposed on the main load-bearing structure, is used to transmit radio frequency signals and receive backscattered signals; A passive impedance sensing component is disposed on the wind turbine blade body and is used to modulate the radio frequency signal into a backscattered signal when the strain signal of the wind turbine blade body is detected. The processor, electrically connected to the reader / writer, is used to extract the signal characteristics of the backscattered signal, determine the current spatial coordinates of the passive impedance sensing component based on the signal characteristics, determine the spatial coordinate offset between the current spatial coordinates and the preset reference spatial coordinates, and determine the damage location of the wind turbine blade in the digital twin model based on the spatial coordinate offset.
2. The system according to claim 1, characterized in that, The passive impedance sensing component includes a strain sensing element, a sensing antenna, and a modulation circuit, wherein the modulation circuit is located between the sensing antenna and the strain sensing element. The strain sensing element has initial circuit parameters, and the strain sensing element is used to modulate the initial circuit parameters into sensing circuit parameters according to the waveform of the strain signal. The modulation circuit is used to transmit the sensing circuit parameters to the sensing antenna; The sensing antenna has an initial reflection coefficient. The sensing antenna is used to receive the radio frequency signal. Based on the sensing circuit parameters, the initial reflection coefficient is modulated into a working reflection coefficient. Based on the working reflection coefficient, the radio frequency signal is reflected to form the backscattered signal.
3. The system according to claim 2, characterized in that, The passive impedance sensing component further includes a flexible substrate, which is electrically connected to the strain sensing element, the sensing antenna, and the modulation circuit.
4. The system according to claim 3, characterized in that, The initial circuit parameters include an initial capacitance value, the sensing circuit parameters include a sensing capacitance value, and the strain sensing element is a capacitor, used to modulate the initial capacitance value into the sensing capacitance value based on the strain signal.
5. The system according to claim 3, characterized in that, The initial circuit parameters include an initial resistance value, the sensing circuit parameters include a sensing resistance value, and the strain sensing element is a resistor, used to modulate the initial resistance value into the sensing resistance value based on the strain signal.
6. The system according to any one of claims 1-5, characterized in that, The number of passive impedance sensing components is multiple, and the passive impedance sensing components are attached to the wind turbine blade body in an array.
7. The system according to claim 6, characterized in that, The number of readers is multiple, and the readers are distributed in different main load-bearing structures.
8. The system according to claim 7, characterized in that, The main load-bearing structure includes a root and a web, at least one of which is connected to the reader / writer.
9. The system according to claim 8, characterized in that, The signal characteristics include at least one of the following: received signal strength indication, signal phase, arrival time, and resonant frequency.
10. The system according to claim 9, characterized in that, The processor is used to establish a mapping database between the reference signal characteristics of the passive impedance sensing component and the reference spatial coordinates when the wind turbine blades are in a healthy state; and to compare and match the signal characteristics with the mapping database to calculate the current spatial coordinates.
11. The system according to claim 10, characterized in that, The system also includes a system linkage interface, and the processor is further used to trigger an external monitor to collect data on the damage location through the system linkage interface after the damage location is determined.