RECORDING OF MEASURED VALUES FOR A WIND TURBINE

Abstract

A method for recording at least one measured value, wherein the measured value is recorded by means of at least one measuring drone, and the measuring drone flies into a predefinable position to record the measured value, is held in the predefinable position by a position adjustment or its change in relation to the predefinable position is recorded, records the at least one measured value, and transmits the at least one recorded measured value or at least one value representing said recorded measured value to an evaluation device and/or stores said recorded measured value.

Claims

1. A method comprising: recording at least one measured value, wherein the at least one measured value is recorded by at least one measuring drone, wherein the recording includes: flying the at least one measuring drone into a predefinable position to record the measured value; holding the at least on measuring drone in the predefinable position by a position adjustment or its change in relation to the predefinable position is recorded; recording the at least one measured value; and storing the at least one recorded measured value or at least one value representing said recorded measured value in a controller.

2. The method as claimed in claim 1, wherein the at least one measured value is a sound value measured by a microphone.

3. The method as claimed in claim 1, wherein the predefinable position is a first predefinable position, the method further comprising flying the at least one measuring drone into a second predefinable position and holding the at least one measuring drone in the second predefinable position by a position adjustment or its change in relation to the second predefinable position, and said measuring drone records at least one further measured value.

4. The method as claimed in claim 1 wherein at least one measured wind value is recorded as a measured value, in particular with a measuring sensor of the drone configured as a measured wind value recording means.

5. The method as claimed in claim 4, wherein at least one value is selected as the at least one measured wind value from the list containing: a wind speed; a wind direction; and a gustiness of the wind.

6. The method as claimed in claim 4, wherein the measuring drone: is held in the predefinable position by a position adjustment; and/or is held in a predefinable attitude by an attitude adjustment; and the at least one wind value is derived from the position adjustment the attitude adjustment or both.

7. The method as claimed in claim 1, wherein at least two measuring drones alternate with one another during the recording of the measured values in order to record the measured values without interruption.

8. The method as claimed in claim 1, wherein a plurality of measuring drones are used simultaneously and record the measured values in different predefinable positions.

9. The method as claimed in wherein the at least one measured value is one of: at least one wind shear, at least one wind veer, and a wind field.

10. The method as claimed in claim 1, wherein the position adjustment of the measuring drone is performed by at least one measuring system, wherein the at least one measuring system is: a measuring system evaluating GPS data, a measuring system evaluating GPS data supplemented with one or more stationary reference receivers, a measuring system evaluating ultrasonic measurements, and a measuring system evaluating radar measurements.

11. The method as claimed in claim 1 further comprising recording weather information, wherein the weather information is one of: air temperature, precipitation type, precipitation quantity, relative humidity, air density, and air pressure.

12. The method as claimed in claim 1, wherein a plurality of measuring drones are held at different heights in relation to one, wherein each of the measuring drones records measured values at the respective heights to form a virtual measuring mast.

13. The method as claimed in claim 1, wherein the at least one measuring drone is positioned upwind of the wind power installation.

14. A method for operating at least one wind power installation, wherein the wind power installation is operated depending on at least one wind value and the at least one wind value is recorded by at least one measuring drone using the method as claimed in claim 1.

15. A measuring drone for recording at least one measured value, the measuring drone comprising: a flight control device configured to cause the measuring drone to fly into a predefinable position and hold the flight control device in the predefinable position, wherein a change in the position of the measuring drone in relation to the predefinable position is recorded; a measuring means configured to record the at least one measured value; and a transmission means configured to transmit to a controller the at least one recorded measured value or at least one value representing said at least one recorded measured value.

16. The measuring drone as claimed in claim 15, wherein the measuring means is at least one microphone configured to record measured sound values.

17. The measuring drone as claimed in claim 15, wherein the measuring means is connected via a cable or a spacer to a main body.

18. The measuring drone as claimed in claim 17, wherein a plate is arranged on the cable or on the spacer between the measuring means and the main body, wherein the plate is a sound-reflecting plate.

19. The measuring drone as claimed in claim 15, wherein the measuring means comprises at least one measured wind value recording means.

20. The measuring drone as claimed in claim 15, comprising: one or more electrically driven propellers with an essentially vertical axis of rotation, wherein the flight control device is prepared to control at least one actuator selected from the list containing: the one or more electrically driven propellers, an adjustment means to adjust alignment of the vertical axis of rotation of each propeller, an attitude control means to control an attitude of the measuring drone, and a direction control means to control a flight direction of the measuring drone.

21. The measuring drone as claimed in claim 15 further comprising: an electric battery configured to store electrical energy, or a trailing cable configured to supply electrical energy.

22. The measuring drone as claimed in claim 15, comprising: one or more propellers driven by at least one internal combustion engine with an essentially vertical axis of rotation, wherein the flight control device is prepared to control at least one actuator selected from the list containing: the one or more electrically driven propellers, an adjustment means for adjusting alignment of the vertical axis of rotation of each propeller, an attitude control means to control an attitude of the measuring drone, and a direction control means to control a flight direction of the measuring drone.

23. (canceled)

24. A measuring arrangement for recording at least one measured value that is a measured sound value or a measured wind value, by using a plurality of measuring drones, and wherein the arrangement comprises: a plurality of measuring drones as claimed in claim 15; and a base station to perform at least one function from the list containing the functions: supplying the measuring drones with electrical energy, capturing recorded measured values, and coordinating the measuring drones with one another.

25. A wind power installation comprising: a nacelle; and a rotor with rotor blades for generating electrical power from wind, wherein: the wind power installation is configured to be controlled depending on at least one measured value; and has a data transmission means configured to receive measured values or values representing said measured values that have been recorded and transmitted by at least one measuring drone as claimed in claim 15.

26. (canceled)

27. The wind power installation as claimed in claim 25, wherein a charging point is provided for the electrical charging of the at least one measuring drone, wherein the charging point is arranged on the nacelle of the wind power installation.

28. A wind power system for generating electrical power from wind, the wind power system comprising at least one wind power installation as claimed in claim 25.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0061] The invention will now be explained in detail below by way of example on the basis of embodiments with reference to the accompanying figures.

[0062] FIG. 1 shows a wind power installation in a perspective representation.

[0063] FIG. 2 shows a windfarm in a schematic representation.

[0064] FIG. 3 shows an example of a control diagram to carry out a method according to the invention.

[0065] FIGS. 4-7 show different configurations of a wind power system with a wind power installation and a plurality of measuring drones.

[0066] FIG. 8 shows a measuring drone with a microphone.

DETAILED DESCRIPTION

[0067] FIG. 1 shows a wind power installation 100 with a tower 102 and a nacelle 104. A rotor 106 with three rotor blades 108 and a spinner 110 is arranged on the nacelle 104. The rotor 106 is set in rotational motion by the wind during operation and thereby drives a generator in the nacelle 104.

[0068] FIG. 2 shows a windfarm 112 with, by way of example, three wind power installations 100, which may be identical or different. The three wind power installations 100 thus represent essentially any number of wind power installations of a windfarm 112. The wind power installations 100 provide their power, i.e., in particular, the generated current, via an electric windfarm grid 114. The currents or powers of the individual wind power installations 100 generated in each case are added together and a transformer 116 is usually provided to step up the voltage in the windfarm and then feed it at the feed-in point 118, which is also generally referred to as the PCC, into the supply grid 120. FIG. 2 is only a simplified representation of a windfarm 112, which, for example, shows no control, although a control is obviously present. The windfarm grid 114 may, for example, also be designed differently in that, for example, a transformer is also present at the output of each wind power installation 100, to name but one different example embodiment.

[0069] FIG. 3 shows a simplified adjustment structure of one embodiment for a position control of a measuring drone, including evaluation of control values of the adjustment for recording measured values, such as wind speed and wind direction. The measuring drone is contained therein as a system 302. During flight operation, the measuring drone 302 is more or less randomly positionable in space and its position is indicated here by the coordinates x, y and z. Here, for example, the coordinate x can indicate a position in the north-south direction, the coordinate y can indicate a position in the east-west direction and the coordinate z can indicate a vertical direction and therefore the height of the measuring drone 302. These three coordinates x, y and z accordingly form the output parameters of the system for the position adjustment.

[0070] A predefined position can be predefined by the corresponding target values x.sub.s, y.sub.s and z.sub.s. A target-actual value comparison is now carried out for each of the coordinates x, y and z on the summing elements 311, 312 and 313, wherein the actual values x.sub.i, y.sub.i, and z.sub.i are incorporated with negative signs.

[0071] In each case, this then produces an adjustment error, i.e., e.sub.x, e.sub.y and e.sub.z. The adjustment errors are then incorporated into the first subcontroller 320. The first subcontroller 320 has an individual thrust controller for each coordinate, i.e., an X thrust controller 321, a Y thrust controller 322 and a Z thrust controller 323. Each of these three thrust controllers of the first subcontroller 320 outputs a thrust which is to be set, i.e., a thrust power which is to be set, in the corresponding coordinate direction, i.e., the thrusts or thrust powers S.sub.x, S.sub.y and S.sub.z. The index in each case indicates the relevant direction. These three thrusts S.sub.x, S.sub.y and S.sub.z can therefore be referred to as control parameters or correcting parameters. The term control parameter is to be preferred here as no direct physical control of an actuator is yet involved, as will become clear below. In this example of a system, as shown in FIG. 3, the implementation is based on a measuring drone 302 which is controlled by controlling its propellers in terms of the rotational speed n and in terms of a tilting of the axis of rotation of the propellers in two tilting directions, i.e., the tilting directions and .

[0072] In order to adjust the vertical position z of the measuring drone 302, it can be assumed in simple terms that this can be achieved via a setting of the rotational speed n. A rotational speed controller 333 is provided accordingly. This controller receives the target vertical thrust S.sub.z as input and calculates a target rotational speed n.sub.s therefrom.

[0073] For the position adjustment in the x direction and y direction, a setting of the vertical axis of the propellers in terms of the two tilting angles and is available as a final control element, wherein these two tilting angles and can be adjusted in directions at right angles to one another. These two tilting angles and should be adjusted together, particularly if the alignment of the measuring drone 302 can vary in relation to the x direction and y direction. The multi-parameter controller 331 is therefore provided in the structure shown by way of example in FIG. 3. This controller takes account jointly of the two thrusts S.sub.x and S.sub.y in the x and y direction respectively and outputs target values for the two tilting angles and , i.e., the target angles .sub.s and .sub.s., as a joint result. In the case of an exact alignment of the measuring drone 302, for example in the north-south direction, if the tilting angle then relates precisely to the north-south direction and the tilting angle relates precisely to the east-west direction, a separation of this multi-parameter controller 331 into two single controllers would be conceivable, so that the proposed thrust in the x direction S.sub.x would therefore directly change only the tilting angle and the thrust in the y direction S.sub.y would directly affect only the tilting angle . However, since this precondition is not normally met, a corresponding conversion into the multi-parameter controller 331 can take place or be taken into account by considering the alignment of the measuring drone 302, which is denoted here as the attitude L. This attitude L is input into the multiparameter controller 331 for this purpose.

[0074] The multiparameter controller 331 together with the rotational speed controller 333 thus forms a second subcontroller 330.

[0075] In any case, the results of this simplified and clear structure shown in FIG. 3 of the multiparameter controller 331 and the rotational speed controller 333 are the target values .sub.s and .sub.s for two tilting angles of the propellers and the target rotational speed n.sub.s for the rotational speed of the propellers. These three target parameters are input accordingly into the system 302 and are therefore transferred to the measuring drone 302 for implementation, or they are transferred to the corresponding final control elements for adjustment of the propeller axes and the motors for setting the rotational speed. These final control elements themselves can of course in each case also have an adjustment structure as an inner control cascade.

[0076] In the idealized case where the measuring drone 302 is located exactly and immovably in its predefined position, i.e., as predefined by the target coordinates x.sub.s, y.sub.s and z.sub.s, a stationary accuracy would be provided for this position adjustment and the adjustment errors e.sub.x, e.sub.y and e.sub.z would therefore be 0. In this situation, the wind speed V.sub.w and wind direction R.sub.w can be derived from the thrusts of the three coordinate directions, i.e., S.sub.x, S.sub.y and S.sub.z. It is of course assumed here, unless there is no wind, that these thrusts S.sub.x, S.sub.y and S.sub.z have non-zero values. The first subcontroller 320 accordingly has an integral component in each of its blocks. Thus, the x thrust controller 321, the y thrust controller 322 and the z thrust controller 323 in each case have an integral or integrally acting component. The measurement recording block or controller 340 receives the three thrust values S.sub.x, S.sub.y and S.sub.z in order to calculate the wind speed V.sub.w and wind direction R.sub.w. In order to allocate the wind values calculated therefrom, i.e., the wind speed V.sub.w and the wind direction L.sub.w to the respective coordinates in which they were recorded, these coordinates x, y and z are similarly input into the measurement recording block 340. The wind values can be allocated accordingly to these coordinates x, y and z. The measurement recording block 340 outputs the wind speed V.sub.w (x, y, z) and the wind direction R.sub.w (x, y, z) accordingly. These wind values can then be further processed and can also be used, taking account of the coordinates allocated to them, in order to record a wind field. To record a wind profile, it may suffice here to take account of the vertical coordinates z only. If the wind field is to be recorded, particularly for the entire rotor plane, the coordinates x and y are also required, wherein the coordinates x and y can be converted into a representation with only one varying horizontal coordinate.

[0077] The air density, for example, can be inferred from the vertical thrust S.sub.z, this being proposed as one aspect.

[0078] Additionally or alternatively to this adjustment according to the simplified adjustment structure shown in FIG. 3, at least the wind speed and wind direction can be derived from the inclination of the measuring drone. If drive rotors are immovably connected to the measuring drone, the rotational speed of each individual rotor and therefore its thrust are adjusted so that the desired inclination and movement direction are set. As a secondary condition, the requirement can be incorporated that the sum of the individual rotor thrusts to maintain the vertical position corresponds exactly to the flight weight or causes a desired upward or downward acceleration.

[0079] For the implementation, the software that is used can output position data and the angle of inclination. These data can be stored and transmitted telemetrically to a ground station. The evaluation can be carried out, for example, at the ground station.

[0080] FIG. 4 shows schematically a wind power system 1 with a wind power installation 100 and a plurality of measuring drones 2. In this schematic representation shown in FIG. 4, the measuring drones 2 are arranged, in relation to the schematically indicated wind 4 which is characterized by corresponding arrows, in front of the wind power installation 100, i.e., upwind of the wind power installation 100. The measuring drones 2 are arranged essentially vertically above one another and thus form a virtual measuring mast 6. According to this variant shown in FIG. 4, a supply cable 8 is provided via which the measuring drones 2 are supplied with electrical energy. The measuring drones share a common supply cable 8, which can also be referred to as a trailing cable. Through the use of this common supply cable 8, the total weight that has to be borne by the measuring drones 2, additionally due to the supply cable 8, is minimized overall. The supply is implemented here via a base station 10 which is configured here as a service vehicle. The measuring drones 2 with the supply cable 8 and the base station 10 thus also form a measuring arrangement 12 for recording at least one measured value by means of the measuring drones 2.

[0081] According to this embodiment, a measurement of measured values in a desired position in relation to the wind power installation 100 can thus be achieved in a simple manner. In particular, it is thus possible to capture not only individual measured values, but also a wind profile or a wind field or, in the case where a microphone is provided, sound profiles or sound fields, in a simple manner, always upwind of the wind power installation 100. This is essentially possible for any prevailing wind direction, since the measuring drones 2 simply have to be guided into the corresponding position upwind of the wind power installation. Said measuring drones can also track the wind in a simple manner so that a measurement can be carried out upwind even after a change in the wind direction. If necessary, the base station 10 which is configured here as a service vehicle and, in particular, provides the electrical supply of the measuring drones 2 can similarly change its position if the wind direction has changed. Alternatively, it can also be provided that the corresponding section of the supply cable 8, particularly the section between the base station 10 and the lowermost measuring drone 2, is so long that the position of the base station 10 does not have to be changed, or at least does not have to be changed in the event of slight changes in the wind direction.

[0082] FIG. 5 shows a design in which a plurality of measuring drones 2 are similarly supplied via a supply cable 8. The supply is implemented here via the wind power installation 100, wherein the supply cable 8 is connected to the nacelle 104 or is connected to a corresponding supply unit in the vicinity of the nacelle 104.

[0083] Here also, various measuring drones 2 are arranged in front of the wind power installation 100 in relation to the wind 4. It is essentially also conceivable to carry out a measurement that is not upwind of the wind power installation, if this is required.

[0084] In any case, a virtual measuring mast 6 which records measured values and, in particular, can also record a height profile of the wind 4 can also be formed in a simple manner with measuring drones 2 according to this embodiment shown in FIG. 5. Further measuring drones 2 which route the supply cable from the nacelle 104 via the rotor 106 to the desired position in which the measurement is intended to be carried out, i.e., in this example upwind of the wind power installation 100, are provided for a cable routing of the supply cable 8. The terms supply cable and trailing cable can be used synonymously here.

[0085] Captured data, in particular measured values or values corresponding thereto, can be transmitted to the wind power installation 100 or, furthermore or alternatively, to the service vehicle 11. A coordination of the measuring drones 2 and particularly the virtual measuring mast 6 also can also be performed by the service vehicle 11. A subtask of a base station, i.e., the energy supply, can be performed here by the wind power installation 100, in particular by a corresponding device in the nacelle 104.

[0086] It should be noted that, in this detailed description of the figures, particularly in the description of FIGS. 4 to 7, the same reference numbers are used for similar, possibly not identical, elements. The service vehicle 11 may, for example, differ between FIG. 4 and FIG. 5 and further figures since it provides the electrical supply of the measuring drones 2 in one case but not in another. The measuring drones 2 may also be identical in the embodiments of FIGS. 4 to 7, but may also differ. It could be provided, for example, that, according to the embodiment shown in FIG. 5, the measuring drones 2 which are arranged in front of the wind power installation 100 have a different evaluation functionality compared with the measuring drones 2 which are provided essentially only to route the supply cable 8. The measuring drones may possibly also differ in terms of their size. In particular, a measuring drone 2 which does not have to carry a trailing cable may possibly be designed as smaller than those measuring drones 2 which have to carry a cable. However, identical measuring drones 2 are preferably used for each position in order to simplify the operation of the measuring arrangement 12.

[0087] The measuring arrangement 12 shown in FIG. 6 and therefore also the wind power system 1 differ from the measuring arrangement 12 and the wind power system 1 shown in FIG. 5 essentially only insofar as a different routing of the supply cable 8 is provided, i.e., from the nacelle 104 and from the rotor 106 of the wind power installation 100 through to the position of the virtual measuring mast 6 in front of the wind power installation 100. Otherwise, reference is made to the embodiment shown in FIG. 5 for further explanations.

[0088] Finally, FIG. 7 shows a wind power system 1 and therefore also a measuring arrangement 12 in which the measuring drones 2 operate without a supply cable. Each measuring drone 2 has a battery or similar electrical energy storage device for this purpose. The measuring drones 2 can be arranged spatially independently from one another. However, the formation of a virtual measuring mast 6 is therefore also possible. A virtual measuring mast 6 of this type is formed here also, i.e., in this example from four measuring drones 2 which are similarly positioned by way of example in front of the wind power installation 100 in relation to the wind 4. These measuring drones 2 shown in FIG. 7 can therefore perform the same tasks as the measuring drones 2 with a supply cable 8 according to the embodiments shown in FIGS. 4 to 6. However, the measuring drones 2 in the embodiments shown in FIGS. 4 to 6 can essentially fly as long as required into their position and can thereby continuously perform measurements and forward the measurement results.

[0089] Two charging points 14 are provided instead for the measuring drones 2. One measuring drone 2 can be charged in each case at these charging points 14, i.e., two measuring drones 2 in total. If at least one measuring drone 2 is charged, an exchange procedure 16 can be carried out in which a charged measuring drone 2 leaves one of the charging points 14 and assumes the position of a measuring drone 2 which can then fly to the charging point 14 and can be charged there. A coordination can be performed here also by the service vehicle 11. The charging points 14, together with the service vehicle 11, can form a base station 10 for the measuring drones 2 and thus for the entire measuring arrangement 12.

[0090] According to one variant, the charging stations, wherein, in the simplest case, one charging station could also suffice, are arranged on the nacelle of the wind power installation 100. As a result, it can also be achieved, inter alia, that the charging points are thereby protected against unauthorized access. The measuring drones can then also operate completely autonomously and require no monitoring.

[0091] According to one embodiment, a solution can be provided in which the measuring drones have batteries or similar electrical energy storage devices which are exchanged for charging. A line of a plurality of batteries, e.g., five or more batteries, can be charged at an identical number of charging points for this purpose. The battery or batteries, in each case fully charged, is/are made available at the end of the line for docking onto a drone. The spent battery is removed from the drone and is placed on a charging point at the back end of the line and is charged there. Fewer drones are thus required for the same functionality and more time is available for charging, thus lengthening the service life of the batteries. An arrangement of this type can also be provided on the nacelle of the wind power installation.

[0092] Wind measurements can be carried out in front of the wind power installation from changing wind directions also. This avoids problems which are known from fixed meteorological masts in that no permanently installed meteorological mast is required, but rather an autonomously flying apparatus with automatic attitude and position adjustment is used at the same distance in the direction of flow in front of the wind power installation. This autonomously flying apparatus is referred to here as a measuring drone.

[0093] The flying object, i.e., the measuring drone, is preferably equipped with electrically driven propellers with a vertical axis of rotation which supply the necessary boosts. This measuring drone can be configured according to the principle of a multicopter. According to one embodiment, deviating from the technology of free-flying drones, batteries or accumulators no longer need to be carried as an energy source for the intended use, and the energy supply can be performed instead via a cable connection. However, the flying height is then limited by the weight of a cable of this type, i.e., a supply cable, whereas the flying time can be unlimited here.

[0094] Alternatively, battery-powered flying objects, i.e., particularly measuring drones with a battery, can be used. Due to the limited flying time, a cyclical replacement of the flying object with a different, freshly charged object can be implemented. In this case, the replacing object, i.e., the measuring drone, flies from a charging point installed on the ground or on the nacelle, such as the charging point 14, to the position of the object which is to be replaced, while the object which is to be replaced flies back to the charging point. The flying objects described here are also referred to as measuring drones and these terms can be used synonymously in this context. If the charging times are greater than the flying times, it is proposed to arrange correspondingly more charging points and objects per object position in order to maintain temporally continuous operation as far as possible.

[0095] Conventional systems, such as, for example, gyros, including electronic gyros, and optical systems or combinations thereof are proposed for the attitude adjustment.

[0096] The position adjustment is intended to hold the object rigidly at a predefined position and height, wherein the position can still be changed. GPS-based systems and possibly ultrasonic devices and radar devices are used for this purpose and for height measurement. The accuracy of GPS-based systems can be substantially improved through the use of stationary reference receivers on or near the wind power installation. This is also known as Differential GPS.

[0097] Since the wind direction and the wind speed are the primarily required measurement parameters, the control parameters calculated by the flight controller to maintain the position can be used directly as a measurement signal. Alternatively or additionally, the flying object could also carry conventional measuring sensors.

[0098] It is proposed, in particular, to station a plurality of these objects, i.e., these flying objects, at a geometric position, but at different heights, thus forming a virtual meteorological mast, i.e., in particular a virtual meteorological mast 6 shown in FIGS. 4 to 7.

[0099] If the wind power installation tracks the wind, i.e., if the wind changes its direction, such a column of flying objects which can form the aforementioned virtual meteorological mast can be transferred into a correspondingly new position, in particular into the then new position upwind of the wind power installation.

[0100] The disadvantage here with a tracking of this type could be the cable-connected energy supply, which would similarly have to track the wind. This can be avoided by means of a preferred embodiment of the invention in which the energy supply of the flying objects, i.e., the measuring drones 2, is provided from the nacelle. FIGS. 5 and 6 show a variant of this type in which the cables are routed around the rotor. This can be done, for example, above or below the rotor, i.e., below the rotor diameter or below the rotor surface.

[0101] A cyclical replacement of battery-powered flying objects, i.e., battery-powered measuring drones, avoids the disadvantages of the cable operation as a whole, but may require a greater number of flying objects and additional charging points with correspondingly higher costs. A cyclical replacement of this type is described by way of example in FIG. 7.

[0102] The invention has been described particularly for measurement for the use of wind power installations. However, other measuring tasks in the atmosphere which involve flows in the range from 0 to 300 meters above ground level and which must invariably be stationary can thereby be performed if necessary.

[0103] However, it is provided, in particular, to use the invention as a replacement for stationary meteorological masts.

[0104] It is thus particularly proposed to provide an arrangement of flying platforms, i.e., flying objects or measuring drones, at fixed positions, i.e., particularly predefinable positions, for measuring purposes. It is advantageous to combine a plurality of such platforms to form virtual meteorological masts. An unlimited flying time is at least theoretically achievable by means of a cable-connected energy supply. An energy supply can be provided here from the ground or from a nacelle of a wind power installation. Position adjustment signals or attitude adjustment signals can be used as a measured value. A telemetric wireless data transmission to a central station is particularly preferably implemented. A central station of this type can form part of a described base station. However, the transmitted data can also be evaluated instead or additionally at other locations, such as in a process computer of a wind power installation or in a windfarm controller in a windfarm in a central evaluation unit which does not have to be in the immediate vicinity of the measuring drones or the aforementioned flying platforms. It should be noted that the term flying platforms is used here to emphasize that flying platforms of this type are not intended to fly as an end in itself, but rather to perform measuring tasks in particular and thus create a platform for the performance of these measuring tasks.

[0105] FIG. 8 shows a measuring drone 2 with a microphone 80. The microphone 80 serves to capture measured values, i.e., measured sound values, such as the sound pressure or frequencies of the sound. The microphone 80 is suspended with a cable 82 below the drone 2 on the main body 84 of the drone 2. The part of the drone on which the propellers 85 are arranged is referred to the main body 84 of the drone 2. A sound-reflecting plate 86 which shields the noises of the drone 2 is located on the cable 82 above the microphone 80.