DE10065314B4 - Method and device for monitoring the condition of rotor blades on wind turbines - Google Patents

Abstract

Method for monitoring the condition of rotor blades on wind power plants by means of a reception, a transmission and a measured value acquisition and processing of signals as well as a signal transformation, an evaluation and a performance of countermeasures, characterized
a) that a measurement of internal rotor resonance, natural frequency, continuous and reflected structure-borne sound signals by means of at least one rotor blade associated sound / vibration receiver (sensor (11, 12)) takes place at whose output electrical, from the material internally transmitted sound Signals converted signals are output,
b) that an input of sound signals selectively from at least one rotor blade associated sound / pulse transmitter (actuator (9, 10)), the triggering in the rotor blade (1, 2, 3) is caused by an evaluation unit (23), or one Self-excitation as a result of operating noise during plant operation,
c) that the electrical signals are converted into a form of spectra,
d) that a comparison is made by means of spectral analysis between these spectra and the spectra of spectral libraries, wherein the spectral libraries are stored in mass data memories (30, 32) and their spectra are defective or undamaged.

Description

The The invention relates to a method for monitoring the condition of rotor blades on wind turbines by means of reception, transmission and measured value acquisition and processing of signals as well as a signal transformation, an evaluation and implementation of countermeasures.

The The invention also relates to a device for carrying out the Procedure, with at least one sensor that receives the received signals into electrical signals, with an evaluation unit, the receives and processes the electrical signals transmitted by the sensors with at least one mass data storage containing spectral libraries with at least one comparison module for spectral analysis and comparing the measured spectrum with those in the spectral libraries held reference spectra and with a countermeasure triggering device.

The rotor blades are highly loaded components whose extension in length and Width has steadily increased over the past few years. At present, theirs is Length to to 40m and at the tips occur high speeds. The rotor blades need centrifugal forces, wind currents, turbulence withstand a wide range of weather conditions in continuous operation.

For the economic Operating a wind turbine, a long life of the rotor blades is crucial. Currently, a lifetime of about 20 years is specified. The problem is that to achieve this lifetime frequent regular checks on-site by visual inspection, e.g. from cranes, necessary are. Repairs always only start when the damage is visually apparent can be seen. In part, the repairs are very expensive. In order to it falls Wind turbine in their power generation during standstill off.

One Problem is that microcracks and material changes preferably within the rotor blade material containing the mechanical Properties and tension conditions already significantly change can, not be detected during the visual inspections.

A device for detecting loads on the rotor blades of a wind turbine is known from the document DE 198 47 982 A1 in which at least one linear element is mounted in the root area of the rotor blades, the load peaks due to vibrations or other overloads of the rotor blade as a whole recorded at the Rotorblattfuß by the relative position of two locations, eg the position of a rotor blade with respect to the shaft or the position of two Rotor blades to each other by a linear element and a displacement detecting position sensor is determined. The linear element detects strains so that certain overload conditions can be selectively detected.

The Problem of the known device is that the loads of the rotor blade considered as a whole unit with a mechanical Device - the Linear element - im Area of the rotor blade foot be measured. This can only make the determination whether the rotor blade was damaged in the area of the rotor blade foot. On the inner condition of the rotor blade but can not make any statement become. It also can not be the area of a faulty state in the entire rotor blade, in particular a damaged spot there be limited to there repair measures in and / or on the material or in the area of the supporting or supporting construction for the achievement a longer one Perform life to be able to. Also can generally punctual damage to Rotor blade can not be detected, which is a shutdown of the plant would require.

A method for determining the technical condition of rotor blades of a wind turbine is disclosed in the document DE 195 34 404 A1 In a model of the wind turbine operating in a computer, the theoretical values for rotational speed and rotational acceleration of the rotor blades as a function of their circulation around the axis of rotation are known, and this is compared with the corresponding measured values of the wind power plant during operation. Here, too, it is a question of monitoring the rotor blades as a whole, to what extent the loads on the rotor blade reaches or exceeds the design values. Material errors that occur during operation are not taken into account. It is assumed from the initial values.

In the DE 199 48 194 A1 describes a method in which the wind turbine is monitored as a unit by recording airborne noise spectra. To do this, a sound pickup is mounted on the outside of the tower to detect changes in the aerodynamic body or ice build-up on the rotor blades as soon as there are noises due to turbulence or specific noise. The problem with this method is that the reference noise spectrum in undisturbed operation already by vibrations that are transmitted from adjacent components on the transducer, or by direct or indirect wind noise, for example, on the rotor blades, and be measured difficult to reproduce sound spectra. A problem is also that the noise spectra have no or vanishingly small portions of the material-related natural frequency spectra and so are not detectable with changes in the material of a single rotor blade.

In addition, from the document DE 42 40 600 C1 in contrast to the method on wind-powered, moving rotor blades, a method for detecting and assessing structural damage to engine or jet-powered aircraft known for the fuselage and its associated rigid wings, in which a generator for excitation signals, namely sine or noise signals used is mounted in the vibration measuring sensors on the aircraft, in which excited with said excitation signals vibrations in the aircraft structure and the resulting vibrations are measured by the sensors, wherein said excitation signals and the signals measured by the sensors in digitized form to a Processor transfer functions are formed in the processor as a quotient of sensor signals and excitation signals, wherein the measured transfer functions are approximated by mathematical functions and in which a modal analysis of the sensor signals of the aircraft structure v is taken.

to execution of the known method to sliding sine signals of constant amplitude or noise signals are used, a finite element model the aircraft structure are set up with the the vibration modes the structure can be calculated and used as reference waveforms serve the modes of vibration obtained from modal analysis the associated Reference vibrations are compared and deviations are determined in the case of deviations, the finite element model for the new aircraft adjusted, but the used aircraft from the deviations from the Finite element model of the initial state structural damage can be localized the localized damages into the finite element model The strength of damaged parts is calculated using the finite element model and be used as residual strength of the aircraft.

One Problem is that with georteten structural damage the Pilots load characteristics of the wings during turns, during Start and landing or maneuvers are given at exceeding them Often not a correction or instant landing will be performed can. Also, the changes that are while of the flight, not immediately signaled, but at the earliest only after the landing. But that can be too late for a correction of flight behavior.

One Another problem is that the excitation with the slip signals constant amplitude or noise signals with aircraft own hydraulic or electrically driven rudder actuator motors from the control surfaces should be made.

When Sensors for the signal acquisition will be accelerometers or strain gauges used. The sensors can both in the wings as well as built into the fuselage. The deviations associated with structural damage when comparing the natural modes with the reference waveforms determined from different amplitude levels.

One Problem is also that with the modal analysis used no continuous monitoring carried out can be, since the test procedures only on the ground and there resting Airplane to be done before and after the flight.

In another publication DE 43 18 016 A1 A method and apparatus for determining and reducing shocks on aircraft and helicopter fuselages during the flight is known in which force generating actuator devices are mounted at certain locations to counteract vibration causing damage to the missile such that the damaging vibrations be weakened. The actuator device consists of a plurality of actuators of an active vibration control system.

The Procedure is for Wind turbines are not suitable because the wind turbine and vibration-free must run, otherwise the shutdown of the wind turbine and fundamental changes required at the facility until the vibrations and shocks are turned off.

Of the Invention is based on the object, a method and a device to monitor the Condition of rotor blades indicate at wind turbines, which is designed so suitable that occurring damages, material changes or material aging on the surface and within the body material of rotor blades at their manufacture, transport or assembly and during operation early and locally determined signal technology recognized, evaluated and at least by supplementary Units are displayed and directly affect the plant operation - all the way to shutdown - taken becomes.

The problem is solved by the method side by the features of claim 1, others Embodiments of the method are mentioned in the subclaims. The method for monitoring according to the preamble of claim 1 is based on the application of natural frequencies and structure-borne noise and sound-running and -reflection, with resonance and natural frequencies, continuous and reflected signal spectra after transmission of excitation signals or from egg ner self-excitation during plant operation as well as operating noise can be measured. The sound signals received by means of at least one rotor blade-associated sensor and converted into electrical output signals are converted into such a form of spectra, so that a comparison with reference spectra can be carried out, which are stored in a mass storage and each of which a defined damage state or an undamaged state of a Rotor blade is assigned. If a deviation from the state in undisturbed operation (normal state) is detectable in the determined spectrum, the rotor blade state associated with this reference spectrum can be determined by means of the assignment of the deviating spectrum to at least one of the reference spectra.

When rotor blade associated Sensor according to the invention is a sound / vibration receiver to understand the relevant, sound signal suitable places of the leaf and Blade foot existing rotor blade embedded or on the surface are attached. To the material properties described above to measure, the embedding of the sensors is preferably carried out in the material of the leaf. Relevant locations are, for example, the blade tip or the edge areas of the leaf.

Corresponding An embodiment of the invention, the reference spectra the basis of model calculations and acoustic measurements from undamaged and of injured rotor blades certain frequency and amplitude spectra and / or spectra shapes / bands get that conditions where spectral libraries are stored on mass data storage from the spectra with the assignment of damage state and damage localization and further information, the received Actual frequency and Amplitude spectra and / or actual spectra forms / bands compared with the spectra stored in the spectra library and the corresponding states are determined, the at Deviations from the normal state of certain damage states and certain defects in the material of the rotor blades are assigned.

To the transmission from the rotating shaft can the measurement signals are analyzed in an evaluation unit by from the received eigen-signal spectrum or from the correlation with the over the actuators fed signals received with the sensors Spectra the relevant frequencies and amplitudes of the time spectrum or a transformed, preferably Fourier-transformed, Spectrum filtered out, which is significant for the condition assessment are.

The Measuring and excitation signals from and to the rotor blades are via a Signal / power supply transfer unit from the shaft to the stator and vice versa, wherein a signal transmission preprocessing unit (Encoder and transmitter) and a signal transmission post-processing unit (Receiver and decoders).

Out the respective comparison between the received actual frequency and amplitude spectra and / or actual spectra forms / bands and the reference spectra stored in the spectral library can be short-term as well as medium and long-term measures for the operation of the wind turbine and for the repair and maintenance of the rotor blades be derived.

At A master computer can have one Information interface, preferably a serial interface, via which the master computer is linked to the evaluation unit, which transmits status information become. Depending on Contents of the status information can be in the host computer automatically the plant operation are influenced up to the rapid shutdown and monitoring the facilities Place measures for the reaction to damage states and information on the initiation of urgency-related measures become.

The Condition monitoring the rotor blades can due to the vornehmbaren by means of the actuators, from the operation of the Plant independent Excitement even while and after production and after transport and during the Installation of the wind turbine to be performed.

in the The following explains the method.

Of the Measuring cycle is triggered in a module for measuring process control and can begin with the output of an excitation signal to the actuator via an exciter signal / auxiliary energy transmission unit, at the same time the gate of the programmable receiving unit for the open the specified measurement period and receive a measurement signal from the sensor as well as time related Frequency amplitude signal digital in the main memory of the central processing unit in a given resolution is filed.

The module for measuring process control, the is responsible for the formation of the exciter signals and received signals, belongs to a comprehensive software program module for the execution of an algorithm, which is preferably located in the central computer unit.

• – Ein Modul zur Messprozesssteuerung,
• – ein Modul zur Messsignalaufbereitung,
• – ein Vergleichsmodul,
• – ein Modul zur Feststellung des Normalzustandes,
• – ein Weiterbetriebsentscheidungs-Modul,
• – ein Modul zur Feststellung eines gestörten Zustandes,
• – ein Modul zur Signalgebung für eine Betriebsweisenänderung, wobei das Modul zur Feststellung eines gestörten Zustandes wahlweise mit dem Weiterbetriebsentscheidungs-Modul in Verbindung stehen kann.

The software program module for processing an algorithm preferably contains the following modules:

• - a module for measuring process control,
• A module for measuring signal conditioning,
• - a comparison module,
• A module for determining the normal condition,
• A post-production decision module,
• A module for determining a disturbed state,
• A mode change signaling module, wherein the fault condition detection module may optionally be in communication with the continue decision module.

In the software program module is made from the one formed in the unit Measurement signal vector in a measurement signal conditioning module, e.g. by means of subsequent fast Fourier transform, a frequency-amplitude spectrum generated. This frequency-amplitude spectrum has the same for the rotor blade typical measured natural frequencies as a spectrum in a typical normalized frequency range. It is also possible, a special, typical Determine the runtime spectrum. Subsequently, by a pattern comparison with the normalized reference spectra stored on mass data memories, that from measurements on rotor blades with defined damage states and / or from model calculations, in a comparison module a corresponding state of the measured rotor blade determined. At the same time, the weather data will influence the natural frequency spectrum can have, such as. Wind speed, wind direction, air temperature, air humidity, from a meterology module and the plant operating data, e.g. rotation speed and power, from a plant operation data module as a parameter considered.

To a comparison with the result of obtaining a normal state is the wind turbine master computer from a corresponding status signal transmitted to the continuing operation decision module and further operation the wind turbine to be maintained.

On the other hand becomes after comparison with the result of receiving a disturbed state Influence on the machine operation taken over by the Interface to the wind turbine master computer a corresponding Information packet in the form of status signals of the rotor blade state, from Signals for damage location and damage description transferred from the status data module that becomes an automatic or one through a dispatcher change to be confirmed the operation of the wind turbine according to a module for signaling for one Mode change leads.

Out an allocation table to the spectrum can be from the mass storage the relevant information as signals for localization and for the description of damage as well as for the necessary maintenance and / or Repair read and also sent to the host computer for forwarding.

To the decision that the damage when comparing spectra as not can be detected from the allocation table to the spectrum of Mass storage the information for localization and damage description and read out of the module for the necessary maintenance and repair and transmitted to the master computer be there to acoustical signaling in the form of a Table and / or in the form of a graphical representation of an action manual to give.

The from the eigenfrequency spectra, sweep and reflection signal spectra received on transmission signals as well as on operating noise and the resulting By transformation obtained signal spectra can both in terms of their individual specific frequency and amplitudes as well as in terms of entities such as frequency bands and frequency amplitude groups be rated.

On the basis of before assembly by model calculations and by determined experimental investigations on undamaged and damaged rotor blades Frequency and amplitude spectra or spectra forms / bands that are unique certain rotor blade conditions, the damage-free and the specific damage attributable states assigned can be can with the received actual frequency and actual amplitude spectra as well as actual spectra forms / bands be compared.

at Deviations will at least receive an indication of whether the deviation a damage condition can be assigned, which gives rise to influence on the operation of the wind turbine, up to the rapid shutdown, to take.

The The object underlying the invention is the arrangement side by a device solved, by the features according to claim 22 is marked. Embodiments of the device are in the associated dependent claims called.

A Device for implementation of the described method can be at least one sound / vibration receiver (sensor) and optionally at least one acoustic / pulse transmitter serving as a pathogen (Actuator), the relevant, sound signal suitable places embedded or on the surface the rotor blades are attached. Both the actuator and the sensor are connected to the evaluation unit connected. This is configured to receive the sound or pulse signals for vibrational excitation produce in the material of the rotor blade, the signals to the actuators transferred to and the time window for the excitation and the reception of the signals by means of the sensors Taxes.

There the evaluation unit arranged in the static part of the wind turbine is the stator in the nacelle, while the actuator and sensor are rotating Part, located between sensor and actuator and the rotating Wave on the one hand and the evaluation unit on the other hand an analogue or digital transmission unit for transmission the excitation signals and the measuring signals. As well as the sensor outgoing signals are electrical, transmission is in both directions on the basis of alternating magnetic fields, radio waves or light signals possible.

Of the Evaluation unit comprises in addition to the comparison module mentioned above, which of the spectral analysis and the comparison of the determined spectrum with reference spectra, a module which follows the Comparison of an assignment of the determined spectrum to a rotor blade state performs. The rotor blade state is characterized both by a damaged state, i.e. the nature and extent of the damage, as well as the location marked in the rotor blade on which the damage occurred is. This assignment leads ultimately to establish the damage and the location of damage in the material of the rotor blade, in which the spectrum is determined has been.

The Sensors and actuators can optionally from the rotor blade foot outgoing fixed signal lines and optional operating power supply lines exhibit.

at Fixed in or on the rotor blade embedded lines are in it the signals to the actuators and from the sensors to and from the rotor blade on each a rotor blade transferable.

The transmission unit are Signalvor- or signal post-processing units, in particular Transmitter with encoder and receiver upstream with decoder.

To belongs to the evaluation unit a configured for it and a programmed computer system that can be accessed by means of an associated operating system as well as measuring and evaluation software generates either exciter signals and sends to the actuators as well as evaluates signals from the sensors and by comparison between the measured spectra and the spectra Spectral libraries, which are preferably stored on mass storage are assignable rotor blade conditions and associated status signals, damage information and operator hints derived, with climate data over the over a Unit for takeover are accessible from climate data as well as plant operating data, such as speed and performance over the interface is available stand, optionally considered become.

The formed status signals of the rotor blades and the associated information can over the interface be transmitted to the host of the wind turbine and there the existing surveillance switched on and for monitoring be retrieved, where the status of the rotor blades displayed there and, if harmful occur, the damage points on the rotor blade and / or within the rotor blades in Form of text, tables or graphics displayed and optionally assigned Safety-related instructions and regulations automatically initiated or suggested to the operator for execution, as well as medium or long-term maintenance or repair measures and their execution is controlled.

Corresponding a particularly advantageous embodiment form the first actuator and the first sensor comprises a first actuator / sensor pair for a leaf-length signal, by using actuator and sensor with as possible great Distance from each other in the longitudinal extent of the leaf are arranged, preferably the actuator in the vicinity of the blade foot and the sensor in the area of the free end of the leaf. One second actuator and a second sensor provide a second actuator / sensor pair for a Leaf wing cross signal For this purpose, actuator and sensor with as possible great Distance apart, but in the transverse dimension of the leaf, i. each at one of its edges, arranged.

The Signal / power supply transfer unit is connected to the evaluation unit, which is connected to the rotating shaft / rotor blades actuator signals outputs and receives sensor signals.

The evaluation unit essentially consists of the central processing unit, a memory, preferably a MOS memory, an operating unit with a connected video terminal, a connected keyboard and a connected printer, a hard disk memory, a removable disk storage and a CD player. ROM drive, from a 6-channel gene programmable sound / pulse generator and a 6-channel programmable measuring signal receiver, which are interconnected via a bus of the central processing unit, wherein the bus preferably a unit for the acquisition of climate data, in particular wind force and temperature, and preferably an interface (serial Interface), with which a communication connection to the parent control computer of the wind turbine can be produced, are connected.

Of the programmable sound / pulse generator is connected via signal lines with the Erregersignal- / power supply transfer unit and the programmable measuring signal receiver via further signal lines with the measuring signal / auxiliary power transmission unit in connection.

On a mass data storage, such as the hard disk or the CD-ROM are, can Digitized reference spectra for the rotor blades for various normal operating conditions also for fault and damage states taken from measurements on normal and defective rotor blades as well from model calculations, preferably with the FEM method.

The Signal / auxiliary energy transmission consists essentially of a transmitting / receiving device in Direction to the actuators of the leaf and a receiving / transmitting device from the direction of the sensors of the leaf, wherein the transceiver and the receiving / transmitting device, the signaling link in Region between rotor and stator, wherein the transmitting / receiving device an exciter signal / auxiliary power transmission unit and the receiving / transmitting means comprises a measurement signal / auxiliary power transmission unit represent, preferably a division with respect to Arrangement on / on the rotor and stator have.

The Erregersignal- / power supply transfer unit is connected to an excitation signal transmission preprocessing unit (Encoder and transmitter) on a stator and an exciter signal transmission post-processing unit (Receiver and decoder) on a rotor part with the actuator signal lines of Rotor blade and the actuator signal output lines leading to the evaluation unit belong, in Connection.

The Measured signal / power supply transfer unit is connected to a measurement signal transmission preprocessing unit (Encoder and transmitter) on a rotor part and a Messsignalü transmission Nachverarbeitungseinheit (Receiver and decoder) on the stator part with the sensor signal lines of Rotor blade and the sensor signal input lines to the evaluation unit to lead, in connection.

The specified method is based on solid-mechanical knowledge, after which every body according to its shape and the specific mechanical Properties with respect to all in the considered spatially extended body possible Owns natural oscillations with their harmonics. These natural vibrations arise for such a body a whole spectrum of frequencies typical of the whole body are. changed the body through internal and / or external damage and Cracks, that's how it changes the spectrum. Certain forms of vibration no longer occur or in modified Shape up.

Just change the vibration modes when the material properties, such as the modulus of elasticity, to change as a result of aging or weathering. This happens a shift in typical frequencies.

Finally acoustic signals that do not correspond to the natural frequencies that through the body to be sent, in the body when going through according to the material properties more or less attenuated and on in the body existing discontinuities and reflected on the body surfaces. Form new discontinuities or change the material properties, that's the reflection signal spectra recognizable by new reflection peaks occurring or the amplitudes change the reflection signals.

These Both acoustic methods are not synonymous with the Method of modal analysis, where it is about the determination of the Own frequencies belonging Deformations of the body go.

The above-mentioned acoustic properties of an extended body can once by appropriate acoustic measurements experimentally or computationally over a Model calculation, e.g. with the finite element model (FEM) become.

The Measurements can at undamaged and damaged rotor blades carried out be possible, with an assignment of the damage state to the spectrum is possible. In the calculations can Damage states, like mechanical damage and cracks or material changes simulated and the spectra are assigned to the damage states. Also can from the FEM recalculation of measured spectra the model and the adjusted model parameters and material properties become.

This can be a database for the Bewer tion of spectra measured in operation and the associated states.

In the rotor blades Wind turbines have at least one sensor and optionally at least one an actor. These sensors / actuators are relevant to sound signal suitable Place embedded or attached to the surface, preferably from the rotor blade foot outgoing permanently installed signal lines and, if necessary, operating power supply lines exhibit. For cables firmly embedded in or on the rotor blade The signals are transmitted to and from the sensors to and from the rotor blade root. The signal transmission from the rotating rotor blade / shaft to the fixed part of the wind turbine is done with a suitable analog or digital measurement signal transmission device preferably based on electrical or magnetic alternating fields, electromagnetic Fields in the range of radio waves or light signal transmission links.

This transfer unit upstream is preferably a signal preprocessing unit. To the transmission The measuring signals are analyzed by the rotating shaft in an evaluation unit. from the received measurement signals or from the in correlation with the over the exciters fed signals received signal responses on the part the measuring signal receiver the relevant frequencies and amplitudes of the time spectrum or a transformed - e.g. Fourier transformed spectrum which filters out significantly for the condition assessment of the rotor blade are.

in the Difference to the modal analysis showing the waveforms e.g. on the wings and analyzed on the fuselage of an airplane, and on the method of transfer functions Here, the acoustic spectra of the system and the measurement and the evaluation of the natural frequencies, self-noise, running signal or reflection effects considered.

The inventive method based on the fact that only with self-excited and foreign excited vibrations and impulses for diagnostic purposes whose amplitudes are not in the area of general Component vibrations range, the rotor blade state monitors becomes.

Is appropriate it, that the rotor blades rotated by wind turbines at least in the area of the rotor blade feet / adjusted can be or activated in the stall-controlled aerodynamic brakes, so that the wind forces can no longer act and thus reduces the rotation to a minimum number of revolutions or even stop what is actually the shutdown or that Shut down the wind turbine means.

further developments and additional Embodiments of the invention are described in further subclaims.

The Invention is based on an embodiment explained in more detail by means of several drawings.

It demonstrate:

1 a schematic representation of a known wind turbine with three rotor blades in central symmetry,

2 a schematic representation of a rotor blade with actuators / sensors that are connected to electrical signal and power lines,

3 a view in the main shaft axis direction on the stator of the signal / power transmission unit with cross section of the main shaft of the wind turbine,

4 a schematic detail of the signal / power transmission unit on the main shaft of the wind turbine,

5 a schematic side view with a transmission winding on the rotor attachment of the signal / power transmission unit,

6 a block diagram of the evaluation unit for controlling the measuring process, for evaluation, monitoring and visualization of the state of the rotor blades and influencing the operating regime of the wind turbine,

7 a block diagram of the signal / auxiliary power transmission unit for actuator signals,

8th a block diagram of the signal / power transmission unit for measuring signals and

9 a schematic flowchart for performing the method for visualization and monitoring of the state of the rotor blades and influencing the operating regime of the wind turbine.

In 1 is the overall view of a wind turbine 40 with the three rotor blades 1 . 2 . 3 attached to a horizontal shaft 6 are fixed, located in the upper end of the mast 4 in a vertically rotatable gondola 5 is shown.

The 2 shows representative of the rotor blade 1 with regard to the three identical rotor blades 1 . 2 . 3 , The rotor blade 1 consists of a leaf wing 7 and from an associated rotor blade foot 8th ,

In the material of the leaf wing 7 There are two actuators 9 and 10 as well as two sensors 11 and 12 , Each of the actors 9 . 10 is with an associated actuator signal line 13 . 14 and auxiliary power lines (not shown) and each of the sensors is connected to a measuring signal line 15 . 16 and auxiliary power lines (not shown) continuously up to the rotor blade foot 8th connected. As a transmission medium in the leaf 7 sound is used. The first actor 9 and first sensor 11 form a first actuator / sensor pair for a leaf longitudinal signal, while the second actuator 10 and the sensor 12 represent a second actuator / sensor pair for a leaf wing cross signal.

In 3 is a view in Hauptwachsachsrichtung on the stator 17 the signal / power transmission unit 20 and the cross section of the shaft passing through the stator 6 in the gondola 5 on the mast 4 shown.

By the in 4 illustrated stator 17 the signal / power transmission unit 20 is the wave 6 led, on which the signal lines 13 to 16 and possibly auxiliary power lines (not shown) to the rotor blade 1 up to the wave-side measuring signal transmission preprocessing unit (transmitter, not shown) 22m the signal / power transmission unit 20 from which the converted signals by means of electromagnetic fields on the part of the unit in the stator 17 transmitting the signal transmission post-processing unit (receiver, not shown) 21m the signal / power transmission unit 20 follows, from which the received measurement signals on the measurement signal lines 15 ' . 16 ' a central processing unit 24 via a programmable measuring signal receiver 34 be supplied.

For the actuator signals, a corresponding device with reversal of the transmission / reception direction is present, which in 7 is shown.

In 5 will be on the shaft 6 attached rotor attachment 18 the signal / power transmission unit 20 with an applied associated winding 19 shown.

The signal / power transmission unit 20 is with an evaluation unit 23 connected.

In 6 is a schematic block diagram of the evaluation unit 23 shown. The evaluation unit 23 consists essentially of the central processing unit (CPU) 24 , from a store 25 , preferably a MOS memory, from an operating unit 26 with a connected video terminal 27 , with an attached keyboard 28 and with a connected printer 29 , from a hard disk drive (hard disk) 30 , a removable disk storage 31 and a CD-ROM drive 32 , from a 6-channel programmable sound / pulse generator 33 and a 6-channel programmable signal receiver 34 that over a bus 35 the central processing unit 24 connected to each other. At the bus 35 are still one unit 36 for taking over climate data, in particular wind force and temperature, and preferably an interface (serial interface) 37 , with which a communication connection to the higher-level master computer 38 the wind turbine 40 is made, connected.

The programmable sound / pulse generator 33 is over the signal lines 13 ' . 14 ' with the exciter signal / power transmission unit 20a connected. The excitation signals to the actuators 9 . 10 run in the direction 51 (Arrow). The programmable measuring signal receiver 34 is over the measuring signal lines 15 ' . 16 ' with the measuring signal / auxiliary power transmission unit 20m connected. The measuring signals from the sensors 11 . 12 run in the direction 50 (Arrow). The control of the over the bus 35 connected units 33 . 20a respectively. 34 . 20m , the data exchange between them and the processing of data is handled by the central processing unit 24 , This is on the hard disk space 30 filed a multitask real-time operating system, its core components in memory 25 , in particular in a MOS memory stand.

On a mass data storage, as is the hard disk space 30 or the CD-ROM drive 32 are still digitized comparative spectra for the rotor blades 1 . 2 . 3 for various normal operating states as well as for fault and damage states, which are obtained from measurements on normal and defective rotor blades as well as from model calculations, preferably with the FEM method.

The following are the 7 . 8th considered together.

The signal / auxiliary power transmission device 20 consists essentially of a transmitting / receiving device in the direction of the actuators 9 . 10 of the leaf 7 and from a receiving / transmitting device from the direction of the sensors 11 . 12 of the leaf 7 , The transmitting / receiving device and the receiving / transmitting device relate to the signaling link in the region between the rotor and the stator 17 wherein the transmitting / receiving device comprises an exciter signal / auxiliary power transmission unit 20a and the receiving / transmitting means comprises a measurement signal / auxiliary power transmission unit 20m each representing a bipartition with respect to rotor and stator 17 have, being on the stator 17 the stator unit 21 with the excitation signal transmission preprocessing unit 21a and the measurement signal transmission post-processing unit 21m is attached and on the rotor, the rotor unit 22 with the measurement signal transmission preprocessing unit 22m and the excitation signal transmission post-processing unit 22a is appropriate.

In 7 is the exciter signal / power transmission unit 20a with the exciter signal preprocessing unit (encoder and transmitter) 21a on a stator part and the exciter signal transmission post-processing unit (receiver and decoder) 22a on a rotor part with the Aktorsignalleitungen 13 . 14 of the respective rotor blade 1 and the actuator signal output lines 13 ' . 14 ' to the evaluation unit 23 belong, shown as a schematic block diagram.

In 8th is the measurement signal / auxiliary power transmission unit 20m with the measuring signal transmission preprocessing unit (encoder and transmitter) 22m on a rotor part and the measuring signal transmission post-processing unit (receiver and decoder) 21m on the stator part with the sensor signal lines 15 . 16 of the respective rotor blade 1 and the sensor signal input lines 15 ' . 16 ' to the evaluation unit 23 lead, shown as a schematic block diagram.

Between the excitation signal transmission pre- and excitation signal transmission post-processing units ( 22a - 21a ) and between the measurement signal transmission front and the measurement signal transmission post-processing units ( 22m - 21m ) is each a transmission link 57 present in which the information and the energy is preferably transmitted on the basis of alternating magnetic fields, radio waves and / or light signals.

In 9 a schematic block diagram and a flow chart of the implementation of a monitoring process with the device according to the invention is shown and explained. The inventive method is set forth with the inventive device for monitoring below for the method using the natural frequencies. In particular, the explanation of the measured value processing steps on which the method is based is based on the flowchart in FIG 9 as well as the 6 ,

The procedure is for the rotor blade 1 shown. In the same way it runs for the other rotor blades 2 . 3 from. The method is based on the application of natural frequencies and structure-borne sound and sound-running and sound reflection behavior, the resonance and natural frequencies, continuous and reflected signal spectra after transmission of excitation signals or from the self-excitation during plant operation and the operating noise, are measured the received and derived from transformation signal spectra are evaluated in terms of their individual specific frequency and amplitudes but also in terms of totalities, based on model calculations and by acoustic measurements of undamaged and damaged rotor blades 1 . 2 . 3 certain frequency and amplitude spectra and / or spectra shapes / bands associated with these states are obtained, storing spectra libraries on mass data 30 . 32 from the spectra with the assignment of damage state and damage localization and other information, preferably for plant operation and for maintenance and repair, are constructed, wherein the received actual frequency and amplitude spectra and / or actual spectra forms / bands with the in spectra are compared and the corresponding states are determined in the case of deviations from the normal state of certain damage states and specific damage sites 39 in the material of the rotor blades 1 . 2 . 3 be assigned.

• – Ein Modul 41 zur Messprozesssteuerung,
• – ein Modul 42 zur Messsignalaufbereitung,
• – ein Vergleichsmodul 46,
• – ein Modul 47 zur Feststellung des Normalzustandes,
• – ein Weiterbetriebsentscheidungs-Modul 56,
• – ein Modul 48 zur Feststellung eines gestörten Zustandes,
• – ein Modul 52 zur Signalgebung für eine Betriebsweisenänderung, wobei das Modul 48 zur Feststellung eines gestörten Zustandes wahlweise mit dem Weiterbetriebsentscheidungs-Modul 56 in Verbindung stehen kann.

The method is a software program module 49 assigned to the processing of an algorithm which preferably contains the following modules:

• - One module 41 for measuring process control,
• - a module 42 for measuring signal conditioning,
• - a comparison module 46 .
• - a module 47 to determine the normal condition,
• - a business continuation decision module 56 .
• - a module 48 for the determination of a disturbed condition,
• - a module 52 signaling for a mode change, wherein the module 48 for determining a fault condition optionally with the further-operation decision module 56 can be connected.

The measuring cycle is triggered in the module 41 for measuring process control and begins with the output of an excitation signal to the actuator 9 via the exciter signal / auxiliary power transmission unit 20a , At the same time the gate of the more channel programmable signal receiver becomes 34 open for the given measuring period and that from the sound transmission 55 Measurement signal from the sensor obtained in the rotor blade 11 received and as time-related frequency amplitude signal digital in memory 25 the central computer unit 24 filed in a given resolution. The module 41 for measurement process control, which is responsible for the formation of the exciter signals and received signals, belongs to the comprehensive software program module 49 for processing an algorithm that is also in the central processing unit 24 located. From the associated measurement signal vector, a frequency-amplitude spectrum or a propagation time spectrum in the module is obtained by subsequent measurement signal processing, eg with fast Fourier transformation 42 generated for measurement signal conditioning. It shows that for the rotor blade 1 typical measured spectra in a typical normalized frequency range. By a pattern comparison with those on a mass storage 30 or 32 stored normalized natural frequency spectra from measurements and / or model calculations is in the comparison module 46 determines a suitable condition. The weather data, such as wind speed, wind direction, air temperature, humidity, from a meterology module 43 and plant operating data, eg, speed and power, from a plant operation data module 44 over the interface 37 from the master computer 38 taken as a parameter.

If it is a normal state after the comparison, then the master computer 38 a corresponding status signal from the further-operation decision module 56 over the interface 37 transmitted and continued operation is maintained.

If, after the comparison, a faulty state is involved, in the case of a considerable damage which has definitely been determined, the machine operation is influenced by the interface 37 a corresponding information packet in the form of status signals of the rotor blade state, of signals for location of the damage location and for description of damage status from the information data module 45 to the master computer 38 is transmitted to an automatic or to be confirmed by a dispatcher change the operation of the wind turbine 40 according to a module 52 to signal for a change of operation. This action is also signaled acoustically in the control room and forwarded to higher-level facilities. From an allocation table to the spectrum from the mass storage 30 . 32 the information is read out as signals for localization and damage description as well as for the necessary repair and also via the interface 37 to the master computer 38 forwarded for forwarding.

If the damage is not detected significantly during the spectral comparison, the allocation table becomes the spectrum of the mass memory 30 . 32 the information on localization and damage description as well as the necessary maintenance and repair from the information data module 45 read out and to the master computer 38 passed there to give an action manual even after acoustic signaling in the form of a table and / or in the form of a graphical representation.

If there is no suitable comparison spectrum for the measured spectrum to be assigned to a fault, then the master computer is used 38 a corresponding status signal is sent with the request to the supervisor to accept the situation and to make a decision. The measured spectrum can be transmitted remotely from the master computer 38 transmitted to the supplier of the monitoring system, the remote diagnostics to the request with a response to the host computer 38 and the dispatcher responds which state is assigned to that spectrum and what actions are required.

The inventive method is based on the use of natural frequencies and structure-borne noise and sound-running and -reflection, since these acoustic properties closely related to the state of a rotor blade 1 . 2 . 3 are linked. Mechanical damage and cracks and material changes inside and on the surface have a significant influence on the acoustic properties, as certain natural frequencies, certain reflection signals, running signal attenuation and the operating noise are closely linked to the mechanical properties. The dependencies can be determined experimentally with measurements on rotor blades of different states and by simulation of the effects of defects and material changes in the rotor blade 1 . 2 . 3 eg calculated with FEM models.

Measured and evaluated are the natural frequency spectra, continuous and Reflection signal spectra on transmitted-sound or impulse signals as well as operating noise. The received and derived from it by transformation signal spectra be considered in terms of their individual specific frequency and amplitudes, but also in terms of entities such as frequency bands and frequency amplitude groups rated.

On the basis of previously through model calculations and through experimental Investigations on undamaged and damaged rotor blades certain frequency and amplitude spectra or spectra forms / bands, the uniquely determined rotor blade conditions, the damage-free and the certain damages states to be assigned, can be assigned are compared with the received actual frequency and actual amplitude spectra as well as actual spectra forms / bands.

In the case of deviations, at least one indication is first of all obtained as to whether the deviation corresponds to one Damage condition can be assigned, which gives rise to influence on the operation of the wind turbine 40 , to the emergency stop, to take. Furthermore, in principle, the location of the damaged area to be assigned to the state becomes 39 on the rotor blade to be monitored 1 reported if the condition is contained in the spectral library. Based on this, measures are proposed for the further operation of the wind turbine 40 as well as for maintenance and repair work to repair the damage. Unmatchable spectra are registered and sent to the evaluation unit responsible for the algorithm for further evaluation 23 or in their extension optionally transmitted via remote data transmission. Optionally, an indication of the condition and the information to the affected wind turbine can be obtained there with a fuzzy logic in conjunction with the otherwise incoming findings of other systems 40 be sent back. For the other rotor blades 2 . 3 the same applies.

One Advantage of the method according to the invention lies in the production of objective evaluation data, which coincides with the currently performed visual considerations is limited.

The invention opens up the possibility that the damaged areas 39 can be detected continuously and in good time by means of integrated technical means through constant monitoring during operation, so that the laborious manual periodic inspections with necessary interruptions to operation can be omitted. On the one hand, this leads to considerable cost savings. On the other hand, the terms of the wind turbines would be 40 extend per year and improve the yield.

Due to the detection of damage in the rotor blades 1 . 2 . 3 already at the time of development - if necessary and possible - repairs can be arranged immediately.

Especially with the coating materials of the rotor blades 1 . 2 . 3 It can be used to prevent damage from increasing to destruction, thus achieving a significant reduction in repair costs. With the invention, a long-lasting shutdown of the wind turbines is thus avoided in the event of destruction, which leads to a significant loss of income.

One Another advantage of the invention is the possibility of material testing of Rotor blade already before installation at the wind turbine by the respective rotor blade first at the factory, then on site after transport and during installation acoustic Investigations are carried out and the signals with standardized Setpoints are compared. Are the signal values within one predetermined tolerance width, a quality-assured state of the rotor blades can be defined become.

Claims (37)

Method for monitoring the condition of rotor blades on wind turbines by means of a reception, transmission and measured value acquisition and processing of signals as well as signal transformation, evaluation and execution of countermeasures, characterized in that a) measurement of rotor blade internal resonant, natural frequency , Continuous and reflected structure-borne sound signals by means of at least one rotor blade-associated sound / vibration receiver (sensor ( 11 . 12 )), at the output of which electrical signals converted from the material-internal sound signals are output, b) that an injection of sound signals is optionally effected by at least one rotor blade-associated sound / pulse transmitter (actuator ( 9 . 10 )), whose triggering in the rotor blade ( 1 . 2 . 3 ) by an evaluation unit ( 23 c) that the electrical signals are converted into a form of spectra, d) that a comparison is made by means of spectral analysis between these spectra and the spectra of spectral libraries, the spectral libraries in mass data storage ( 30 . 32 ) and their spectra are assigned to defective or undamaged rotor blades (reference spectra), so that in the case of deviations from the normal state, the states corresponding thereto are determined via the reference spectra and damage states and damaged areas ( 39 ) in the material of the rotor blade ( 1 . 2 . 3 ) and e) that steps a to d are completed before countermeasures are taken. Method according to claim 1, characterized in that that on the basis of model calculations and by acoustic Measurements of undamaged and of injured rotor blades certain frequency and amplitude spectra and / or spectra shapes / bands which are the respective damage-free or known damaged condition of the rotor blade (rotor blade state) are assigned, and that the spectral libraries from the thus obtained reference spectra with the assigned damage status and the damage location and further information, preferably for plant operation as well as Maintenance and repair measures, being constructed. Method according to one of claims 1 or 2, characterized in that the measurement signals after a transmission from the rotating shaft ( 6 ) in an evaluation unit ( 23 ) can be analyzed by taking from the received eigen-signal spectrum or from the in correlation with the via the actuators ( 9 . 10 ) input signals received spectra from the sensors ( 11 . 12 ) the relevant frequencies and amplitudes of the time spectrum or a transformed, preferably Fourier-transformed spectrum are filtered out, which are significant for the condition evaluation. Method according to one of the preceding claims, characterized in that the measuring and excitation signals from and to the rotor blades ( 1 . 2 . 3 ) via a signal / power transmission unit ( 20 ) from the wave ( 6 ) to the stator ( 17 ) and vice versa, and signal transmission preprocessing units (encoders and transmitters) ( 21a . 22m ) and signal transmission post-processing units (receivers and decoders) ( 22a . 21m ) be used. Method according to one of the preceding claims, characterized in that from the respective comparison between the received spectra and the reference spectra short-term as well as medium and long-term measures for the operation of the wind turbine ( 40 ) and for the repair and maintenance of the rotor blades ( 1 . 2 . 3 ) be derived. Method according to one of the preceding claims, characterized in that to a host computer ( 38 ), in which the system operation can be automatically influenced up to the rapid shutdown, the status information via an interface ( 37 ), preferably a serial interface, are transmitted and the measures for reacting to malfunction states and / or information for initiating urgency-related measures are communicated to an installation monitoring system. Method according to one of the preceding claims, characterized in that the condition monitoring of the rotor blades ( 1 . 2 . 3 ) during production and after transport on site and during installation in the wind turbine area ( 40 ) is carried out. Method according to one of the preceding claims, characterized in that preferably in an associated central processing unit ( 24 ) a software program module ( 49 ) processes one of the algorithms using a module ( 41 ) for measurement process control, a module ( 42 ) for measurement signal conditioning, a comparison module ( 46 ), a module ( 47 ) for determining the normal state of a further-operation decision module ( 56 ), a module ( 48 ) for determining a faulty condition and / or a module ( 52 ) for operating mode signaling, wherein the module ( 48 ) for determining a fault condition optionally with the further-operation decision module ( 56 ). Method according to claim 8, characterized in that the measuring cycle in the module ( 41 ) is triggered to the measuring process control and this with the output of an excitation signal from a programmable sound / pulse generator ( 33 ) to the actuator ( 9 . 10 ) via an excitation signal / auxiliary energy transmission unit ( 20a ), at the same time the gate of a programmable signal receiving unit ( 34 ) for the given measuring period and that from the sound transmission ( 55 ) measured signal obtained from the sensor in the rotor blade ( 11 . 12 ) and as a time-related frequency amplitude signal digitally in a main memory ( 25 ) of the central processing unit ( 24 ) is stored in a predetermined resolution. Method according to one of claims 8 or 9, characterized in that from the measurement signal vector obtained by the measurement by means of subsequent transformation, preferably a fast Fourier transformation, a frequency-amplitude spectrum in the module ( 42 ) is generated for measuring signal processing, wherein the frequency-amplitude spectrum for the rotor blade ( 1 . 2 . 3 ) has typical measured natural frequencies as a spectrum in a typical normalized frequency range, and by a pattern comparison with those on the mass data storage ( 30 . 32 ) stored normalized natural frequency reference spectra from measurements and / or model calculations in the comparison module ( 46 ) a corresponding state is determined, wherein the weather data, eg wind speed, wind direction, air temperature, air humidity, from a meterology module ( 43 ) and plant operating data, eg speed and power, from a plant operating data module ( 44 ) are taken into account as parameters. Method according to one of claims 8 or 9, characterized in that from the measurement signal vector obtained by the measurement of trajectory and reflection signals by means of subsequent transformation, a frequency-dependent time-amplitude spectrum in a module ( 42 ) is generated for measuring signal processing, wherein the time-amplitude spectrum for the rotor blade ( 1 . 2 . 3 ) has typical measured transit times and reflections as a spectrum in a typical normalized frequency and time window range, and where by pattern matching with those on the mass data memories ( 30 . 32 ) stored normalized natural frequency reference spectra from measurements and / or Model calculations in a comparison module ( 46 ) a corresponding state is determined, wherein the weather data, eg wind speed, wind direction, air temperature, air humidity, from a meterology module ( 43 ) and plant operating data, eg speed and power, from a plant operating data module ( 44 ) are taken into account as parameters. Method according to one of Claims 8 to 11, characterized in that, after a comparison with the result of the maintenance of a normal state, the master computer ( 38 ) a corresponding status signal from the further-operation decision module ( 56 ) is transmitted and the continued operation is maintained. Method according to one of Claims 8 to 11, characterized in that, after the comparison with the result of the receipt of a faulty state, influence is exerted on the machine operation, in that, via the interface ( 37 ) a corresponding information packet in the form of status signals of the rotor blade state, of signals for location of the damaged area and for the description of damage status from the information data module ( 45 ) to the master computer ( 38 ), which changes to an automatic or a change of operation of the wind turbine ( 40 ) according to a module ( 52 ) leads to signaling for a mode change. Method according to one of claims 6 to 13, characterized in that from an allocation table to the reference spectrum from the mass data storage ( 30 . 32 ) the information as signals for localization and damage description and the necessary maintenance and repair and also to the host computer ( 38 ) are forwarded for onward transmission. A method according to claim 14, characterized in that after a decision, which detects the damage as a result of the spectral comparison as not significant, from the allocation table to the reference spectrum of the mass data storage ( 30 . 32 ) the information on localization and damage description as well as the necessary maintenance and repair from the information data module ( 45 ) and sent to the master computer ( 38 ) are transmitted in order to give instructions for action even after acoustic signaling in the form of a table and / or in the form of a graphic representation. Method according to one of claims 6 to 15, characterized in that in the case that for the measured, deviating from the normal state spectrum, there is no suitable comparison spectrum, the master computer ( 38 ) a corresponding status signal is sent with the request to the monitoring for remote diagnostic clarification, wherein the measured spectrum also via a remote data transmission from the master computer ( 38 ) can be transmitted to the service of the monitoring system manufacturer, who can then provide assistance. Method according to one of claims 10 to 16, characterized that from the eigenfrequency spectra, sweep and reflection signal spectra received by transmission signals as well as the operating noise and from it obtained by transformation signal spectra both in terms their individual special frequency and amplitudes as well as in terms of ensembles such as frequency bands and frequency amplitude groups be rated. Method according to one of the preceding claims, characterized characterized in that on the basis of before assembly through Model calculations and experimental tests on undamaged and damaged Rotor blades determined Reference spectra associated with clearly determined rotor blade conditions can be with the received actual frequency and actual amplitude spectra as well as actual spectra forms / bands be compared. Method according to one of the preceding claims, characterized in that in case of discrepancies between the compared spectra at least one indication is obtained as to whether the deviation can be assigned to such a damage condition giving rise to influence on the operation of the wind turbine ( 40 ), to the emergency stop. Method according to one of the preceding claims, characterized in that in non-assignable spectra optionally obtained with a fuzzy logic in conjunction with the otherwise incoming findings of other wind turbines an indication of the state and the information to the affected wind turbine ( 40 ) are returned. Method according to one of the preceding claims, characterized in that the state examination of the Ro torblattes ( 1 . 2 . 3 ) before installation on the wind turbine ( 40 ) takes place by the respective rotor blade ( 1 . 2 . 3 ) first in the factory, then on site after the transport and during assembly subjected to acoustic examinations and the signals are compared with standardized target values. Device for monitoring the condition of rotor blades on wind turbines by means of a Method according to one of the preceding claims, with at least one sensor which converts the received signals into electrical signals, with an evaluation unit which receives and processes the electrical signals transmitted by the sensors, with at least one mass data memory in which spectral libraries are located, with at least one comparison module for spectral analysis and comparison of the measured spectrum with the reference spectra stored in the spectral libraries and with a countermeasure triggering device, characterized in that a) at least one rotor blade-associated sensor ( 11 . 12 ) for receiving rotor blade-internal sound signals and optionally at least one rotor blade-associated actuator ( 9 . 10 ), b) that the actuators ( 9 . 10 ) and the sensors ( 11 . 12 ) with the evaluation unit ( 23 ), in which the electrical excitation signals can be generated, are in communication and the excitation signals to the actuators ( 9 . 10 ) are transferable to the emission of sound signals inside the rotor blade, c) that between the sensors ( 11 . 12 ) and actuators ( 9 . 10 ) on the one hand and the evaluation unit ( 23 ) On the other hand, a signal / auxiliary power transmission unit ( 20 ), in which the measurement signal and excitation signal transmission takes place, and d) that in the evaluation unit ( 23 ) at least one module ( 47 . 48 ) for determining a condition of a rotor blade ( 1 . 2 . 3 ) due to an association of determined spectra and / or spectra shapes / bands of the rotor blade ( 1 . 2 . 3 ) is present to the states of defective or undamaged rotor blades in such a way that damage states and damaged areas ( 39 ) in the material of the rotor blade ( 1 . 2 . 3 ) are detectable. Device according to claim 22, characterized in that the sensors ( 11 . 12 ) and actuators ( 9 . 10 ) optionally from the rotor blade foot ( 8th ) outgoing fixed signal lines ( 13 . 14 . 15 . 16 ) and optionally operating power supply lines ( 53 . 54 ) exhibit. Device according to claim 22 or 23, characterized in that when fixed in or on the rotor blade ( 1 . 2 . 3 ) embedded signal lines ( 13 . 14 . 15 . 16 ) in it the signals to and from the actuators / sensors ( 9 . 10 . 11 . 12 ) from and to the rotor blade root ( 8th ) on each of a rotor blade ( 1 . 2 . 3 ) are transferable, wherein for the signal transmission from the rotating shaft ( 6 ) to a stator ( 17 ) in the gondola ( 5 ) of the wind turbine ( 40 ) an analog or digital signal / auxiliary power transmission unit ( 20 ) is arranged for measuring signals. Device according to one of Claims 22 to 24, characterized in that the signal / auxiliary energy transmission unit ( 20 ) Signalvor- or signal postprocessing units are assigned, which in particular transmitter with encoder and receiver are preceded by a decoder. Device according to one of claims 23 to 25, characterized in that a module ( 41 ) is responsible for measuring process control for the formation of the excitation signals and the detection of the received signals. Device according to one of claims 22 to 26, characterized in that the evaluation unit ( 23 ) comprises a configured and programmed computer system in which by means of an associated operating system and measurement and evaluation software either excitation signals generated and to the actuators ( 9 . 10 ) as well as those of the sensors ( 11 . 12 ) are evaluated, and in which as a result of a comparison between a measured spectrum and preferably on mass data storage ( 30 . 32 ) information signals and damage information of the rotor blade and operator instructions for the wind turbine can be output, wherein for consideration in comparison, climate data on a unit ( 36 ) for the transfer of climate data and plant operating data, such as speed and power, via an interface ( 37 ) are available. Device according to one of claims 22 to 27, characterized in that the evaluation unit is assigned an interface and the interface with a host computer ( 38 ) of the wind turbine ( 40 ) is connected, at which the formed status signals of the rotor blade ( 1 . 2 . 3 ), the damage information and the operator information can be transmitted and the status of the rotor blades ( 1 . 2 . 3 ), if damage conditions occur, the damaged areas ( 39 ) on and / or inside the rotor blade ( 1 . 2 . 3 ) in the form of text, tables or graphics as well as medium or long-term maintenance or repair measures are displayed. Device according to one of claims 22 to 28, characterized in that a first actuator ( 9 ) and a first sensor ( 11 ) form a first actuator / sensor pair for a leaf longitudinal signal, while a second actuator ( 10 ) and a second sensor ( 12 ) represent a second actuator / sensor pair for a leaf-wing cross signal. Device according to one of Claims 22 to 29, characterized in that the signal / auxiliary energy transmission unit ( 20 ) with the evaluation unit ( 23 ) connected is. Device according to one of claims 22 to 30, that the evaluation unit ( 23 ) essentially from the central processing unit ( 24 ), from a memory ( 25 ), preferably a MOS memory, from a control unit ( 26 ) with a connected video terminal ( 27 ), with an attached keyboard ( 28 ) and with a connected printer ( 29 ), from a hard disk space ( 30 ), a removable disk storage ( 31 ) and a CD-ROM drive ( 32 ), from a 6-channel programmable sound / pulse generator ( 33 ) and a 6-channel programmable signal receiver ( 34 ), which has a bus ( 35 ) of the central processing unit ( 24 ), whereby on the bus ( 35 ) preferably a unit ( 36 ) for the acquisition of climate data, in particular wind force and temperature and preferably an interface ( 37 ), with which a communication connection to the higher-level master computer ( 38 ) of the wind turbine ( 40 ) can be produced, are connected. Device according to one of Claims 22 to 31, characterized in that the programmable sound / pulse generator ( 33 ) via signal lines ( 13 ' . 14 ' ) with the excitation signal / auxiliary energy transmission unit ( 20a ) and the programmable measuring signal receiver ( 34 ) via further signal lines ( 15 ' . 16 ' ) with a measuring signal / auxiliary energy transmission unit ( 20m ). Device according to one of claims 22 to 32, characterized in that on a mass data storage digitized comparison spectra for the rotor blades ( 1 . 2 . 3 ) are stored for various normal operating states as well as for fault and damage states which are obtained from measurements on normal and defective rotor blades and from model calculations, preferably with the FEM method, climate data such as air speed, temperature and humidity as well as system operating data such as speed and performance, parameters can be. Device according to one of Claims 22 to 33, characterized in that the signal / auxiliary energy transmission device ( 20 ) substantially from a first receiving / transmitting device in the direction of the actuators ( 9 . 10 ) of the leaf ( 7 ) of the rotor blade ( 1 . 2 . 3 ) as well as from a second receiving / transmitting device from the direction of the sensors ( 11 . 12 ) of the leaf ( 7 ), wherein the first and second transmitting / receiving device of the signaling linkage of rotor and stator ( 17 ), wherein the first transceiver device comprises an exciter signal / auxiliary energy transmission unit ( 20a ) and the second receiving / transmitting device, a measuring signal / auxiliary power transmission unit ( 20m ), which preferably have a bipartition with respect to the arrangement on / on the rotor and stator ( 17 ), wherein on the stator ( 17 ) a stator unit ( 21 ) with an excitation signal transmission preprocessing unit ( 21a ) and a measurement signal transmission post-processing unit ( 21m ) are mounted on the rotor and a rotor unit ( 22 ) with a measurement signal transmission preprocessing unit ( 22m ) and an excitation signal transmission post-processing unit ( 22a ) are mounted. Device according to Claim 34, characterized in that the excitation signal / auxiliary energy transmission unit ( 20a ) with an exciter signal preprocessing unit (encoder and transmitter) ( 21a ) on a stator part and the exciter signal transmission post-processing unit (receiver and decoder) ( 22a ) on a rotor part with actuator signal lines ( 13 . 14 ) of the rotor blade ( 1 . 2 . 3 ) and actuator signal output lines ( 13 ' . 14 ' ), which belong to the evaluation unit ( 23 ), communicate. Device according to one of claims 34 or 35, characterized in that the measuring signal / auxiliary energy transmission unit ( 20m ) with a measurement signal transmission preprocessing unit (encoder and transmitter) ( 22m ) on a rotor part and the measurement signal transmission post-processing unit (receiver and decoder) ( 21m ) on the stator part with sensor signal lines ( 15 . 16 ) of the rotor blade ( 1 . 2 . 3 ) and sensor signal input lines ( 15 ' . 16 ' ), which belong to the evaluation unit ( 23 ), communicate. Device according to one of Claims 34 to 36, characterized in that between the exciter signal transmission front and the exciter signal transmission postprocessing units ( 22a - 21a ) and between the measurement signal transmission front and the measurement signal transmission post-processing units ( 22m - 21m ) each transmission links ( 57 ) are present, in which the information / signals and the energy / signals are preferably transferable on the basis of alternating magnetic fields, radio waves and / or light signals.