State monitoring device, rotor blade, and wind turbine comprising same

Abstract

The invention relates to a state monitoring device for at least one rotor blade (16) of a wind turbine (10), having at least one flexible sensor device with a plurality of measuring sections, which are arranged on a plurality of sections of the rotor blade (16) and are designed so as to measure at least one respective parameter, and a processing device for detecting and / or processing the measured parameters. The invention also relates to a rotor blade (16) for a wind turbine (10), having at least one such state monitoring device, and to a wind turbine (10), having such a state monitoring device or such a rotor blade.

Description

[0001] Title: Condition monitoring device, rotor blade and wind turbine therewith

[0002] Description

[0003] The invention relates to a condition monitoring device for at least one rotor blade of a wind turbine, a rotor blade having such a condition monitoring device, and a wind turbine having such a condition monitoring device.

[0004] Wind turbine rotor blades require regular maintenance because they are exposed to wind, weather, and other influences, such as bird strikes. A key part of a maintenance visit is checking for physical damage to the rotor blades. Such damage can be caused, for example, by quality fluctuations in manufacturing, which can lead to the separation of bonded structures or the detachment of individual layers. Furthermore, damage can occur during use, for example, due to fatigue fractures, lightning strikes, and / or corrosion.

[0005] For designs made from materials where damage is readily visible, a visual inspection of the rotor blades is performed. Other materials may require follow-up inspection, for example, using ultrasound.

[0006] Despite regular inspections, the aging state of the rotor blades can only be determined very imprecisely, so large safety margins are factored into the design of the rotor blades. Since the frequency of both isolated events with sometimes high loads, such as bird strikes or hail, as well as the contribution of changing external influences, such as weather, particularly frost and ice, is difficult to predict and also depends on the exact location of the wind turbine, inspections are also scheduled at a frequency that includes a safety margin. Complex loads, such as shear and moment loads, are only inadequately modeled. Due to the high and changing loads on the rotor blades, regular inspections are necessary at least once a year.

[0007] During an inspection, a wind turbine is forced to shut down and cannot generate electricity. Depending on the design, disassembly of the rotor blades may be necessary. Even today, wind turbine inspections are primarily carried out by human technicians.

[0008] All these aspects result in high costs, which represent a significant proportion of the total costs over the lifetime of a wind turbine.

[0009] Against this background, the invention solves the problem of reducing the effort caused by inspections.

[0010] The object is achieved by a condition monitoring device according to claim 1, a rotor blade according to claim 10, and a wind turbine according to claim 12. Advantageous embodiments are the subject of the dependent claims.

[0011] The problem is solved by a condition monitoring device for at least one rotor blade of a wind turbine, comprising at least one flexible sensor device with a plurality of measuring sections, wherein the measuring sections are arranged and configured to measure at least one parameter at a plurality of sections of the rotor blade, and a processing device for recording and / or processing the measured parameters. Measuring mechanical parameters of the rotor blade at a plurality of measuring sections allows the determination of cumulative loading as well as short-term overloads of the rotor blade. This allows conclusions to be drawn about the likelihood of damage to the rotor blade after a certain period of time. Accordingly, the inspection intervals can be adapted to the conditions prevailing at the installation site of the wind turbine.This reduces unnecessary inspections and thus also the effort caused by the inspections.

[0012] In some embodiments, the processing device is configured to detect a state of the rotor blade based on the detected parameters, wherein the state may be at least one of the normal state, warning state and / or shutdown state.

[0013] The processing device thus allows the numerous measured mechanical parameters to be summarized into a single result that is easily understood by the operator. Conditions relevant to operation can be selected for detection.

[0014] In some embodiments, the condition monitoring device is associated with an inspection device for inspecting the rotor blade, wherein the inspection can be triggered by detecting a predetermined condition.

[0015] This allows an automatic inspection of the rotor blade to be triggered without technician intervention, for example, when a warning condition is detected. This further reduces inspection costs.

[0016] In some embodiments, the inspection device comprises an unmanned aerial vehicle (UAV) for inspecting the rotor blade. Such an unmanned aerial vehicle (UAV) can particularly easily perform an inspection, such as a visual inspection, of the rotor blade, for example, from the outside. Disassembly of the rotor blade is not necessary, making this inspection particularly time-saving or even possible via remote control.

[0017] In some embodiments, the inspection device comprises an unmanned, surface-based drone for inspecting the rotor blade.

[0018] Such a drone can, for example, efficiently perform a surface inspection and / or an ultrasonic inspection. This eliminates the need for manual inspections, which require maintenance personnel to climb on and / or inside the rotor blades. Furthermore, disassembly of the rotor blade, which is conceivable in extreme cases, is also unnecessary. This makes this inspection particularly time-saving or can even be performed remotely. Ideally, an inspection performed by drones can be automated. Such drones can be used on both the outer and inner surfaces of the rotor blade.

[0019] In some embodiments, the sensor device may be heatable at least in sections.

[0020] This makes it possible, for example, to cost-effectively remove ice from the rotor blade. In particular, it is possible to cost-effectively cover large areas of the rotor blade with the sensor device. Furthermore, the heatable sensor device can at least impede the formation of ice on the surface of a rotor blade before it even begins to form. In some embodiments, at least part of the

[0021] Sensor device can be laminated together with layers of the rotor blade.

[0022] This ensures particularly precise recording of mechanical parameters through the frictional connection with the rotor blade material, thus improving the precision of detecting the need for inspection. Furthermore, if the sensor device is designed to be heatable, no additional heating layer made of a material unsuitable for lamination is necessary in the rotor blade.

[0023] In some embodiments, the sensor device comprises a sensor fabric.

[0024] Such sensor fabrics are particularly adaptable to curved shapes, such as rotor blades. They are also space-saving, lightweight, easy to process, and provide a wide range of measurement sections in a particularly simple manner.

[0025] In some embodiments, the sensor device comprises an energy harvesting device.

[0026] This enables largely autonomous operation of the condition monitoring device, for example through piezoelectric energy recovery from vibration.

[0027] The object is further achieved by a rotor blade for a wind turbine, comprising at least one of the above-mentioned condition monitoring devices.

[0028] By incorporating the condition monitoring device, inspection intervals are adjusted to the actual load on the rotor blade, thus reducing the effort required for inspections. Furthermore, especially when the sensor fabric is used over large areas, detailed analysis of mechanical and / or other parameters is possible immediately and / or continuously. This allows, for example, a digital twin of the rotor blade to be created in a computer to identify problems and / or gain insights into the properties of the rotor blade, for example, for material testing.

[0029] In some embodiments, the sensor device is at least partially laminated into the rotor blade.

[0030] This enables particularly precise measurement of the mechanical parameters on the rotor blade.

[0031] The object is further achieved by a wind turbine having at least one of the above-mentioned condition monitoring devices.

[0032] By incorporating the condition monitoring device, the inspection intervals are adjusted to the actual load on the rotor blade, thus reducing the effort required for inspections. If the sensor device is designed to be heatable, ice formation and the associated damage can be prevented from the outset, thus extending the inspection intervals. In some embodiments, the wind turbine has a control device for controlling the wind turbine, wherein the control device is configured to shut down the wind turbine upon detection of a predetermined shutdown condition.

[0033] If the processing device detects an overload and / or damage to at least one rotor blade based on the measured mechanical parameters, the wind turbine is automatically shut down.

[0034] This allows an immediate inspection of the rotor blade that triggers the shutdown, for example by means of the inspection device if the wind turbine has such an inspection device.

[0035] Example

[0036] An embodiment of the invention is illustrated in the drawings and explained in more detail below. They show:

[0037] Fig. 1 is a schematic representation of a wind turbine according to an embodiment of the present invention;

[0038] Fig. 2 is a schematic representation of a section of a rotor blade with sensor devices according to an embodiment of the present invention;

[0039] Fig. 3 is a schematic representation of a laminated section of a rotor blade with a laminated sensor fabric according to an embodiment of the invention and

[0040] Fig. 4 is a schematic representation of a cross section through a rotor blade with possible arrangements of sensor devices according to embodiments of the present invention.

[0041] The figures contain partially simplified, schematic representations. In some cases, identical reference symbols are used for identical, but possibly not identical, elements. Different views of identical elements may be scaled differently.

[0042] Directional indications such as “left”, “right”, “top” and “bottom” are to be understood with reference to the respective figure and can vary in the individual representations compared to the object depicted.

[0043] The wind turbine 10 shown in Fig. 1 has a nacelle 12 on which a hub 14 is mounted, from which rotor blades 16 protrude. One of the rotor blades 16 has a flat sensor device with a sensor fabric 18, each of which has a plurality of measuring sections for measuring at least one parameter. The sensor fabric 18 is arranged in or on the rotor blade 16 so that it can measure the parameter(s) on and / or in a plurality of sections of the rotor blade 16.

[0044] The wind turbine 10 further comprises an inspection device 20. In some embodiments, the inspection device comprises, for example, an unmanned aerial vehicle, such as a drone. In some embodiments, the inspection device comprises, for example, an unmanned surface-based vehicle, for example, for inspecting inner and / or outer surfaces of the rotor blade 16.

[0045] A control device 22 is provided for controlling the wind turbine 10. The control device 22 comprises, in particular, a processing device for detecting the parameters measured by the sensor fabric 18. The processing device and / or the control device 22 can be configured to detect a state of the rotor blade 16 based on the detected parameters, wherein the state can be at least a normal state or a warning state.

[0046] For example, the sensor device together with the processing device forms a condition monitoring device.

[0047] For this purpose, the processing device monitors, for example, whether the measured mechanical parameters exceed predetermined maximum values ​​or fall below predetermined minimum values. In further embodiments, the processing device can also monitor, for example, whether the measured mechanical parameters deviate from predetermined normal values ​​by a predetermined factor. The predetermination of the normal values ​​can also be carried out, for example, by calibration after installation of the wind turbine 10.

[0048] The processing device detects a rotor blade condition from the measured mechanical parameters, for example, using one or more of the rules mentioned in the previous paragraph. As long as the mechanical parameters do not exceed the predetermined limits, i.e., they do not exceed the predetermined maximum values, fall below the predetermined minimum values, and / or deviate from the predetermined normal values ​​by more than a predetermined factor, the processing device detects a normal condition.

[0049] As soon as the mechanical parameters leave the predetermined limits, the processing device detects a warning condition, for example.

[0050] In addition to detecting a condition, the processing device can, for example, in some embodiments, assign the events and / or parameters relevant for triggering the respective condition to the measurement sections and thus to the sections of the rotor blade where they occurred. Furthermore, the processing device can classify the parameters and / or their changes.

[0051] The warning state can mean, for example, that an inspection of at least one of the rotor blades 16 is necessary because a mechanical event has been detected that could have led to damage. For this purpose, the sensor fabric 18 can be designed, for example, to measure a parameter, such as pressure, strain, temperature, vibration, humidity, and / or acceleration at the measuring sections. For example, a point load event caused, for example, by hail, ice on the rotor blades, or bird strike, which could lead to damage, could be measured as a short-term pressure increase that exceeds a predetermined maximum pressure. Damage to the rotor blade 16 could also occur, for example, if a permanent strain on the rotor blade 16 is detected by the sensor fabric 18.

[0052] There are a variety of other known conditions that could trigger a warning condition. In some embodiments, the processing device may include sensors for environmental conditions or receive data from such sensors, for example, humidity and / or temperature. If these measured environmental conditions, for example, move outside a desired range, the processing device may detect a warning condition. In some embodiments, the processing device may, for example, be configured to sum measured mechanical loads over a longer period of time, weight measured mechanical loads, and / or combine measured mechanical loads from different measurement sections to detect a warning condition. In further embodiments, the processing device may detect other conditions, for example, a shutdown condition indicating a necessary shutdown of the wind turbine 10.These embodiments can be combined as desired to achieve reliable detection of warning and / or shutdown states.

[0053] In some embodiments, the wind turbine 10 may, for example, be configured to use the warning state as a shutdown state. Thus, if the control device 22 detects a warning state (and thus simultaneously a shutdown state), it shuts down the wind turbine 10, for example.

[0054] In some embodiments, the wind turbine 10 can be configured, for example, such that an inspection is triggered by the inspection device 20 when the warning condition or the shutdown condition is present. Furthermore, the wind turbine 10 can be configured, for example, such that the inspection is only triggered when the wind turbine 10 has been shut down and the rotor blades 16 have come to a standstill.

[0055] A plurality of sensor fabrics 18 are arranged on or in a section of the rotor blade 16 shown in Fig. 2. One sensor fabric 18 is arranged in the region of a leading edge 24, one sensor fabric is arranged in the region of a trailing edge 26, and one sensor fabric 18 is arranged on an inner side 28 of the rotor blade 16.

[0056] The sensor fabrics 18, which are arranged in the area of ​​the leading edge 24 and the trailing edge 26, can be designed, for example, to measure strain, pressure, and temperature. The sensor fabric 18, which is arranged on the inner side 28 of the rotor blade 16, can be designed, for example, to measure vibrations.

[0057] In some embodiments, at least one of the sensor fabrics 18 is heatable. This can be achieved in particular by conducting current through the heatable sensor fabric 18, thereby heating it. Such a heatable sensor fabric 18 is advantageously arranged, for example, in the region of the leading edge 24, since ice formation can occur more frequently there. In some embodiments, the processing device can be configured to determine a need to heat the sensor fabric 18 from sensors, for example of the sensor fabric 18 and / or other connected sensors. In this case, the processing device can largely autonomously prevent or at least impede icing of the rotor blade 16. For this purpose, the processing device can, in some embodiments, have a Cl decision device.

[0058] The sensor fabrics 18 can, for example, be arranged on a surface of the rotor blade 16. In further embodiments, the sensor fabrics 18 can, for example, also be arranged within the walls of the rotor blade 16. This is particularly advantageous when the rotor blade 16 comprises a material formed from several interconnected layers (composite material).

[0059] A section of such a composite material is shown in Fig. 3. The sensor fabric 18 is arranged, for example, as an additional layer between several material layers 30. Due to this arrangement and the direct connection to the layers 30, the sensor fabric 18 can, for example, directly measure the mechanical parameters to which the material layers 30 are also subject. This allows individual events, such as bird strikes or hailstorms, to be detected and localized with particular precision.

[0060] One of many possible arrangements of the sensor fabrics 18 in the rotor blade 16 is shown, for example, in Fig. 4. The sensor fabrics 18 can be arranged not only in outer walls of the rotor blade 16, for example, in the region of the leading edge 24 or the trailing edge 26, but also in internal structures, such as a web 32. In some embodiments, the processing device can be implemented separately from the control device 22. In further embodiments, multiple processing devices can be provided.

[0061] In some embodiments, the sensor fabric 18 may also extend over the entire outer surface of the rotor blade 16 or even within the entire walls of the rotor blade 16. In further embodiments, for example, sensor fabric 18 is provided in at least 10%, at least 50%, at least 80%, or at least 95% of the walls of the rotor blade 16.

[0062] The sensor fabric 18 can, for example, be a fabric that has measuring fibers, for example, fibers whose resistance changes upon stretching. In further embodiments, the measuring fibers can have piezoelectric properties. The measuring fibers are arranged in the fabric, for example, in such a way that the processing device can detect the desired parameter at a plurality of measuring sections, for example directly or by combining the measured electrical properties of the measuring fibers. In further embodiments, the sensor fabric 18 can, for example, have fibers made of nanotubes. In further embodiments, the fibers can, for example, also provide a power supply.

[0063] In some embodiments, the sensor fabric 18 may include an energy harvesting device, for example, piezoelectric and / or piezoresistive fibers. The electrical energy harvested by such fibers, for example, from vibration, can be used to power devices, such as the processing device and / or the processing device. In some embodiments, for example, a rechargeable battery may be provided for storing electrical energy.

[0064] In some embodiments, the processing device and / or the condition monitoring device comprises a communication device by means of which the acquired measured parameters and / or a detected condition of the rotor blade 16 can be transmitted to a communication partner, for example, a server, a router, and / or a relay. In particular, for monitoring larger wind farms, a combination of the acquired measured parameters from different wind turbines 10 can be provided. In some embodiments, the acquired measured parameters can be processed by means of a processing device, in particular a CL processing device, in order to detect a possible warning condition and / or shutdown condition.

[0065] The condition monitoring device according to the invention can be easily integrated into existing designs of rotor blades 16, since the flexible sensor device allows it to be integrated into the existing material structure without compromising the properties or performance of the material of the rotor blades 16. The flexibility of the sensor device means, in particular, that the sensor device can be arranged along a straight or curved surface. Since the incorporation of the condition monitoring device according to the invention into the rotor blades 16 does not change the process for producing the rotor blades 16, the condition monitoring device can also be easily manufactured.

[0066] The electronics required for operation, for example for the processing device and / or the control device 22, can be arranged outside the rotor blades 16, for example, and, if necessary, designed to be replaceable. The devices and methods described here can be implemented at least partially using software on commercially available computers. For example, states can be implemented by contents of a memory location in a computer's main memory. For example, the condition monitoring device and / or the processing device can comprise a computer, for example with connections to sensor devices, wherein the sensor devices can supply digital and / or analog data, for example measurement data, which are processed by software executed on the computer to form the devices.The division of the implementation of devices into hardware and / or software is left to the implementing specialist as a technical exercise.

[0067] The described condition monitoring device allows, for example, an autonomous response of the wind turbine 10 to unexpected mechanical load conditions, to environmental changes, for example, ice formation, and, in the event of a warning condition, a subsequent inspection, for example, using a drone. The condition monitoring device can be operated largely autonomously, for example, by energy recovery from vibration and / or air-controlled response to environmental influences, for example, to prevent ice formation.

[0068] List of reference symbols

[0069] wind turbine

[0070] gondola

[0071] hub

[0072] rotor blade

[0073] Sensor fabric

[0074] Inspection facility

[0075] Control device

[0076] leading edge

[0077] trailing edge

[0078] inside

[0079] Material layer

[0080] web

Claims

Claims: Condition monitoring device for at least one rotor blade (16) of a wind turbine (10), comprising at least one flexible sensor arrangement with a plurality of measuring sections, wherein the measuring sections for measuring at least one parameter are arranged and configured on a plurality of sections of the rotor blade (16), and a processing device for acquiring and / or processing the measured parameters. Condition monitoring device according to claim 1, characterized in that the processing device is configured for detecting a condition of the rotor blade (16) based on the parameters, wherein the condition can be at least one of the following states: normal state, warning state, and / or shutdown state.Condition monitoring device according to claim 2, characterized in that the condition monitoring device is associated with an inspection device (20) for inspecting the rotor blade (16), wherein an inspection can be triggered by the detection of a predetermined condition. Condition monitoring device according to claim 3, characterized in that the inspection device (20) comprises an unmanned aerial vehicle (UAV) for inspecting the rotor blade (16). Condition monitoring device according to claim 3, characterized in that the inspection device (20) comprises an unmanned, surface-bound drone for inspecting the rotor blade (16). Condition monitoring device according to any one of the preceding claims, characterized in that the sensor device is at least partially heatable. Condition monitoring device according to any one of the preceding claims, characterized in that at least one section of the sensor device is laminateable together with layers of the rotor blade (16). Condition monitoring device according to any one of the preceding claims, characterized in that the sensor device comprises a sensor fabric (18). Condition monitoring device according to any one of the preceding claims, characterized in that the sensor device comprises an energy harvesting device.Rotor blade (16) for a wind turbine (10), comprising at least one condition monitoring device according to one of the preceding claims. Rotor blade (16) according to claim 10, characterized in that at least one section of the sensor device is laminated into the rotor blade (16). Wind turbine (10) comprising at least one condition monitoring device according to one of claims 1 to 9 or a rotor blade according to one of claims 10 or 11. Wind turbine (10) according to claim 12 and claim 2, characterized by a control device for controlling the wind turbine, wherein the control device is configured to switch off the wind turbine upon detection of a predetermined shutdown state of the rotor blade (16).

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