METHOD FOR CONDITION MONITORING OF A DRIVE STRUCTURE OR TOWER OF A WIND POWER PLANT AND WIND POWER PLANT

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a method for monitoring the condition of a drive train or tower of a wind turbine, as well as to a wind turbine. In particular, the invention relates to a wind turbine and an associated method that, for example, has sensors on one structure and can monitor the condition of another, mechanically coupled structure using these sensor data. TECHNICAL BACKGROUND

[0002] It is well known that collecting data from wind turbines promotes the sensible and safe operation of a wind turbine or wind farm. One example is wind speed measurement data, which is used to control blade pitch adjustment or, if wind speeds become too high, to shut down the rotor or turbine to protect it from damage.

[0003] Data can be collected from a variety of sensors on a wind turbine. In general, it seems desirable to collect as much data as possible about a wind turbine in order to be able to make the most accurate statements about its condition.

[0004] In practice, however, very few wind turbines are equipped with a complete set of sensors. Therefore, not all wind turbines have sensors on all relevant components. Furthermore, it would be desirable to create redundancy where appropriate.

[0005] It is therefore desirable to improve wind turbines and wind farms in such a way that the condition of relevant components can be monitored. Documents DE 10 2011 117468 A1 and DE 20 2013 007142 U1 disclose various prior art relevant to the invention. SUMMARY

[0006] Embodiments of the present disclosure provide a method for monitoring the condition of a tower of a wind turbine according to claim 1 and a wind turbine according to claim 7.

[0007] According to one embodiment of the present disclosure, a method for condition monitoring of a tower of a wind turbine is provided. The method comprises acquiring data from a condition monitoring system, wherein the condition monitoring system is provided for a structure of the wind turbine that is mechanically coupled to the drive train or tower; processing the acquired data from the condition monitoring system provided for the structure of the wind turbine that is mechanically coupled to the drive train or tower; and determining a condition of the drive train or tower from the processed data from the condition monitoring system provided for the structure of the wind turbine that is mechanically coupled to the drive train or tower.

[0008] According to a further embodiment of the present disclosure, a wind turbine is provided. The wind turbine comprises at least one drive train and one tower; a condition monitoring system, wherein the condition monitoring system is provided for a structure of the wind turbine that is mechanically coupled to the drive train or tower; and a data processing device configured to carry out a method for condition monitoring of a drive train or tower of a wind turbine.The method comprises acquiring data from a condition monitoring system, the condition monitoring system being provided for a structure of the wind turbine that is mechanically coupled to the drive train or tower; processing the acquired data from the condition monitoring system being provided for the structure of the wind turbine that is mechanically coupled to the drive train or tower; and determining a condition of the drive train or tower from the processed data from the condition monitoring system being provided for the structure of the wind turbine that is mechanically coupled to the drive train or tower. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Embodiments of the invention are illustrated in the drawings and explained in more detail in the following description. In the drawings: Fig. 1 shows an exemplary wind turbine according to embodiments; Fig. 2 shows a section of an exemplary wind turbine and a diagram illustrating natural frequency ranges according to embodiments; and Fig. 3 shows a flowchart illustrating an exemplary method for monitoring the condition of a drive train or tower of a wind turbine. DESCRIPTION OF EMBODIMENTS

[0010] Embodiments of the present disclosure are explained in more detail below. The drawings serve to illustrate one or more examples of embodiments. In the drawings, like reference numerals designate the same or similar features of the respective embodiments. Features described as part of one embodiment may also be used in conjunction with another embodiment, thus forming another embodiment.

[0011] Embodiments described herein can monitor or determine the condition of a structure by acquiring data from a structure that is mechanically coupled to that structure. Embodiments described herein particularly enable the condition monitoring of a drive train or tower of a wind turbine by means of a condition monitoring system that is connected to a structure mechanically coupled to the drive train or tower. This system is particularly advantageous for wind turbines that do not have a monitoring system for the drive train and / or the tower and / or for which redundancy is to be created. Another, additional monitoring system may also be desired, one that, for example, has a higher data rate and / or data depth, is easily accessible and / or is better integrated into the system of the wind turbine.

[0012] For example, according to embodiments described herein, instead of measuring the vibrations at the drive train or tower directly at the drive train or tower, the vibrations at the drive train or tower may also be measured indirectly in the rotor.

[0013] In particular, natural frequencies measured on the rotor blades or other mechanically coupled structures can be classified. The natural frequencies measured on this structure can be categorized as blade natural frequencies, tower natural frequencies, drivetrain natural frequencies, etc. The frequencies classified as drivetrain natural frequencies can then be monitored for changes in both frequency values ​​and amplitudes and mode shapes. The same can be implemented analogously for the tower.

[0014] The Figure 1 shows an exemplary wind turbine 10. On the wind turbine 10 according to Figure 1For example, several sensors 11, 12, 13, 14, 15 are arranged. The sensors 11, 12, 13, 14, 15 can acquire data. The data can be relevant to the operation of the wind turbine. Furthermore, a data processing device 16 can be provided. The data processing device 16 can process the acquired data. The processed data can be transmitted via a network interface 18. In particular, the network interface 18 can be configured to connect the data processing device to a data network. The network interface can be configured to send data processed by the data processing device 16, for example, to an online-based storage and server service. The data processing device 16 can, for example, use and / or be a digital processor unit ("DPU").

[0015] Sensors 12, 13, 14, 15 can be sensors that record measurement data of a wide variety of parameters, for example, of a rotor, a gearbox, a generator, and / or generally of a (different) structure, such as a tower, on the wind turbine. One or more sensors 11, 12, 13, 14, 15 can be mounted on a wind turbine. Consequently, unless explicitly stated otherwise, the present disclosure always assumes at least one sensor or a combination of several sensors, even if only "sensor" in the singular is used for ease of addressing.

[0016] According to the embodiments described herein, a sensor 11, 12, 13, 14, 15 can be arranged on the wind turbine. The sensor 11, 12, 13, 14, 15 can be arranged on a rotor blade of the wind turbine, on a turbine of the wind turbine, on a gearbox of the wind turbine, on a tower of the wind turbine, etc., or can be an external sensor.

[0017] For example, the sensor 11, 12, 13, 14, 15 can be an optical sensor. According to embodiments described herein, the sensor 12, 13, 14, 15 can be a fiber optic sensor. In particular, the sensor 12, 13, 14, 15 can be a fiber optic strain sensor or acceleration sensor. The sensor 12, 13, 14, 15 can measure in one, two, three, or more than three axes. In particular, the sensor can be a 2D or 3D sensor.

[0018] The sensor 11, 12, 13, 14, 15 can be connected to the data processing device 16. For example, the sensor 11, 12, 13, 14, 15 can be connected to the data processing device 16 via a wired or wireless connection. If the sensor 11, 12, 13, 14, 15 and the data processing device 16 are arranged on parts of the wind turbine 10 that can move relative to one another, such as the rotor and the nacelle, a wireless connection can be advantageous. A wireless connection can be implemented, for example, via radio, in particular via a Bluetooth standard or WLAN standard.

[0019] According to embodiments described herein, the wind turbine 10 may have a sensor 15 on a rotor blade. In particular, one sensor may be provided for each rotor blade 15. The sensors 15 may be part of a condition monitoring system for the rotor blades and / or the rotor. The rotor and the rotor blades represent a structure mechanically coupled to the tower and / or the drive train. The data processing device 16 may provide condition monitoring of the drive train or tower of the wind turbine using data from the condition monitoring system of the mechanically coupled structure. In particular, the data processing device 16 may acquire data from a condition monitoring system, wherein the condition monitoring system is provided for a structure of the wind turbine that is mechanically coupled to the drive train or tower.Furthermore, the data processing device 16 can be configured to process the acquired data from the condition monitoring system provided for the structure of the wind turbine that is mechanically coupled to the drive train or tower. The data processing device 16 can also determine a condition of the drive train or tower from the processed data from the condition monitoring system provided for the structure of the wind turbine that is mechanically coupled to the drive train or tower.

[0020] Alternatively or additionally, the data processing device 16 can also send the acquired data via the network interface 18, so that the further processing of the data does not (only) take place directly in the wind turbine 10.

[0021] According to embodiments described herein, the at least one sensor 11, 12, 13, 14, 15 can be arranged on at least one rotor blade, a rotor, or a hub of the wind turbine. Preferably, the sensor 15 is arranged on a rotor blade. According to embodiments described herein, the sensor 11, 12, 13, 14, 15 can be a fiber optic sensor. According to embodiments described herein, the sensor 11, 12, 13, 14, 15 can be a vibration sensor or acceleration sensor. In particular, the sensor 11, 12, 13, 14, 15 can be a 2D or 3D acceleration sensor.

[0022] According to embodiments described herein, data processing device 16 may be configured to determine natural frequencies and / or determine a change in natural frequencies. In particular, the natural frequencies of the structures to which a sensor is connected and / or to which a sensor is attached, as well as of structures mechanically coupled to these structures, may be determined and monitored for changes. For example, a change in an amplitude and / or a mode shape of the natural frequencies may be monitored.

[0023] According to embodiments described herein, monitoring can also lead to the determination of a deviation of the wind turbine from normal behavior. For example, the sensor data can be used to determine whether it is within a normal range. Alternatively or additionally, the deviation of the wind turbine from normal behavior can also be determined based on the natural frequencies. In particular, based on the natural frequencies, normal operating states can be classified as distinct from abrupt, abnormal states, and a trend behavior can be identified.

[0024] According to embodiments described herein, natural frequencies can be classified as drivetrain natural frequencies or tower natural frequencies and monitored for changes. In particular, the monitoring system for a mechanically coupled structure can be used for this purpose.

[0025] Figure 2shows a section of an exemplary wind turbine 10 as well as a diagram illustrating natural frequency ranges according to embodiments.

[0026] In the Figure 2 The sensor 15 arranged on a rotor blade and the data processing device 16 are shown as an example. Figure 2 A diagram illustrating the frequencies detected by sensor 15 over the rotor speed. The diagram shows five distinguishable tracks as examples. The bottom three tracks (1. Flapwise, 1. Edgewise, 2. Flapwise) can be assigned to the rotor or rotor blades. The second track from the top can be assigned to the drive train. The top track can be assigned to the tower.

[0027] As the Figure 2shows, the data acquired by a condition monitoring system of a structure can also be used for the condition monitoring of a structure that is mechanically coupled to it. In particular, the Figure 2 that the data from the rotor condition monitoring system allows condition monitoring of the drive train or tower.

[0028] In general, the expected values ​​for the natural frequencies can depend on various factors, such as the type and / or design of the wind turbine 10. Typically, the tower natural frequencies can lie between the rotor frequency (1P) and the excitation frequency of the passing rotor blades (3P). This can be particularly the case with a so-called soft tower. In rarer cases, "soft-soft" towers are used, in which the tower natural frequencies lie below the 1P rotor frequency.

[0029] According to embodiments described herein, frequencies in the range up to 10 Hz can be used to monitor the tower's natural frequency. In particular, frequencies in a range between 0.25 and 2 Hz can be classified as the tower's natural frequency.

[0030] According to embodiments described herein, frequencies above the tower and rotor blade natural frequencies can be used to monitor the drive train natural frequency. Typical generator speeds are between 900 and 2000 revolutions per minute. Therefore, frequencies above 15 Hz (1P of the generator) and multiples thereof can be used to monitor the drive train natural frequency and / or classified as drive train natural frequency.

[0031] According to embodiments described herein, natural frequencies can be categorized by the magnitude of the frequency, the amplitude, and / or the damping value, as well as by analyzing the mode shapes and / or directions. Furthermore, further categorization can be performed by comparing the measured natural frequencies between the blades. Frequencies that are measured the same on all three blades (same frequency, amplitude, and phase) usually do not originate from the blades themselves, but rather from one of the mechanically coupled structures. Lower frequencies typically originate from the tower and the parts of the drive train upstream of the gearbox. Higher frequencies typically originate from the gearbox and the generator.

[0032] According to embodiments described herein, a frequency measurement can also be carried out in the hub of the rotor, for example by the sensor 11, 12, 13, 14, 15. By comparing the frequencies measured in the hub with the frequencies measured in the blade, a categorization can be made additionally or alternatively.

[0033] Figure 3 shows a flowchart illustrating a method 40 for monitoring the condition of a drive train or tower of a wind turbine according to embodiments. The wind turbine 10 can, for example, be the wind turbine 10 from Figure 1 and 2 be.

[0034] According to a box 41, the method comprises acquiring data from a condition monitoring system, wherein the condition monitoring system is provided for a structure of the wind turbine 10 that is mechanically coupled to the drive train or tower. In particular, the acquired data can be vibration data. According to a box 42, the method comprises processing the acquired data from the condition monitoring system provided for the structure of the wind turbine 10 that is mechanically coupled to the drive train or tower. According to a box 43, the method comprises determining a condition of the drive train or tower from the processed data from the condition monitoring system provided for the structure of the wind turbine 10 that is mechanically coupled to the drive train or tower.It should be noted at this point that the aspects and embodiments described herein can be combined with one another as appropriate, and that individual aspects can be omitted where this is reasonable and possible within the scope of the skilled person's skill. Modifications and additions to the aspects described herein will be familiar to those skilled in the art. The scope of the invention is defined in the claims.

Claims

1. A method for monitoring the state of a tower of a wind turbine (10), wherein the method comprises: collecting data of a state monitoring system, wherein the state monitoring system is provided for a structure of the wind turbine (10) which is mechanically coupled to the tower; processing the collected data of the state monitoring system which is provided for the structure of the wind turbine (10) which is mechanically coupled to the tower; and determining a state of the tower from the processed data of the state monitoring system which is provided for the structure of the wind turbine (10) which is mechanically coupled to the tower, characterized in that the structure is at least a rotor blade, a rotor, or a hub of the wind turbine (10).

2. The method according to claim 1, wherein the state monitoring system has at least one sensor (11, 12, 13, 14, 15) arranged on the structure, wherein in particular the sensor (11, 12, 13, 14, 15) is a fiber-optical sensor.

3. The method according to claim 1 or 2, wherein processing the data includes determining eigenfrequencies.

4. The method according to claim 3, wherein eigenfrequencies are classified as tower eigenfrequencies and are monitored for changes.

5. The method according to claim 4, wherein a change in an amplitude and / or a mode shape of the eigenfrequencies is monitored.

6. The method according to any one of the preceding claims, wherein the collected data is vibration data.

7. A wind turbine (10), comprising: a powertrain and a tower; a state monitoring system, wherein the state monitoring system is provided for a structure of the wind turbine (10) which is mechanically coupled to the tower; and a data processing device (16) which is adapted to execute the method according to any one of the preceding claims, wherein the structure is at least a rotor blade, a rotor, or a hub of the wind turbine (10).

8. The wind turbine according to claim 7, wherein the state monitoring system has at least one sensor (11, 12, 13, 14, 15) arranged on the structure, wherein in particular the sensor (11, 12, 13, 14, 15) is a fiber-optical sensor.

9. The wind turbine according to claim 8, wherein the sensor is a vibration sensor.

10. The wind turbine according to claim 8 or 9, wherein the sensor is a 2D or 3D acceleration sensor.