WO2020173602A1

WO2020173602A1 - Rotor blade adjusting device for wind turbines

Info

Publication number: WO2020173602A1
Application number: PCT/EP2020/000052
Authority: WO
Inventors: Heinz-Hermann Letas
Original assignee: Senvion Deutschland Gmbh
Priority date: 2019-02-26
Filing date: 2020-02-26
Publication date: 2020-09-03
Also published as: DE102019001355A1

Abstract

The invention relates to an adjusting device for at least one rotor blade (13) of a wind rotor (12) of a wind turbine, having a blade control module (2) and an adjusting motor (20), which is connected to an electrical power supply and which actuates the rotor blade (13) in order to modify the angle of attack thereof, wherein the blade control module (2) comprises a control device which, in a normal mode, actuates the adjusting motor (20) in a controlled manner and, in an emergency mode, the adjusting motor (20) can be actuated independently of the control device, wherein the adjusting motor (50) has a shunt winding (5). In addition to the control device, an emergency speed setting device of the adjusting motor (20) is provided, which, in the emergency mode, is designed to increase or to decrease a flow through the shunt winding (5) depending on a desired speed change of the adjusting motor (20). By means of the flow, the invention thus achieves, in a remarkably simple manner, robust control of the speed of the adjusting motor in the emergency mode which is completely independent of the regular control device.

Description

Rotor blade adjustment device for wind turbines

The invention relates to a rotor blade adjustment device for wind energy installations, a wind energy installation equipped therewith, and their respective operation.

Modern wind energy plants have a wind rotor with adjustable rotor blades. Here, the rotor blades of the wind rotor can be changed with regard to their angle of attack by means of a rotor blade adjustment device. This angle of attack is also referred to as the pitch angle based on the technical term for angle of attack customary in the English-speaking world, namely "pitch". The rotor blades adjustable in this way are therefore also referred to as pitch-adjustable rotor blades. Compared to the previously common type of wind turbine with fixed rotor blades, the so-called stall-regulated wind turbines, these offer the advantage that, by adjusting the rotor blades, the mechanical power of the wind turbine, which is taken from the wind and fed into the generator system of the wind turbine, and thus ultimately also the electrical power output can be influenced. In particular, this enables the wind energy installation to “go out of the wind” in order to enable safe and efficient operation even in the case of high wind speeds. Another considerable advantage of wind energy installations with pitch-adjustable rotor blades is that in the event of a fault, the wind energy installation can be shut down quickly by moving the rotor blades into a flag position. In the event of malfunctions or when the wind turbine is shut down for safety reasons, for example due to strong storm winds, it can be achieved that the rotor behaves like a flag and no longer exerts any torque on the rotor shaft or the generator.

With regard to the rotor blade adjustment device, a basic distinction is made between three different operating modes. A first operating mode is normal operation, namely a supply of the rotor blade adjustment device from the network with electrical energy and regulation by its own control device with an actuator for the adjustment motor. This normal operating mode is also referred to as "regulated network operation". - If the network fails, a supply is provided from a storage battery provided for this purpose, with the operation of the rotor blade adjustment device still being regulated by its own control device. - If the control device or its actuator finally fails, the accumulator continues to be supplied, but speed control can no longer take place. Of the

CONFIRMATION COPY The adjusting motor is therefore operated without regulation. A wind energy installation with a correspondingly designed rotor blade adjustment device is known from EP 1 744 444 A1).

In the last-mentioned operating mode, the speed can no longer be controlled, but the result is a speed depending on an idle speed of the motor and external conditions, such as the loads exerted by aerodynamic forces on the rotor blade, the drive force (torque) of the variable speed motor depending on a Voltage of the accumulator and a temperature of the motor or accumulator. Thus there is no positive control over the speed and the adjustment rate (degrees / second) of the rotor blade. This is disadvantageous because, for reasons of safety and stability, certain adjustment speeds for the rotor blades should not be exceeded if possible. In addition, synchronization is not guaranteed with several rotor blades of the wind rotor.

This results in the unpleasant risk that differences can arise between the rotor blades of the wind rotor, which lead to different blade angles and thus to undesirable additional loads. For a safe shutdown, especially in strong winds, this is counterproductive.

The invention is based on the object of creating an improved rotor blade adjustment device or a wind energy installation provided with such an improved rotor blade adjustment device, as well as the respective operating method, in which this disadvantage is avoided.

The solution according to the invention lies in the features of the independent claims. Advantageous further developments are the subject of the dependent claims.

In the case of an adjusting device for at least one rotor blade of a wind rotor of a wind power plant, with a blade control module and an adjusting motor which is connected to an electrical power supply and actuates the rotor blade to change its pitch angle, the blade control module comprising a control device which, in normal operation, the adjusting motor controlled actuated, and in emergency operation the adjusting motor can be actuated independently of the control device, the adjusting motor having a shunt winding, according to the invention, in addition to the control device, an emergency speed setting device of the adjusting motor is provided, which is designed to flow through the shunt winding in emergency mode depending on to increase or decrease a desired change in the speed of the variable displacement motor. The invention is based on the idea of providing an (more simply designed) independent emergency speed setting device in addition to the control device. This acts on the shunt winding of the adjusting motor. The invention has recognized that by (preferably exclusive) intervention in the excitation of the shunt winding in emergency operation, a change in speed can be carried out, specifically with simple means, that is, even if the actual control device has failed. According to the invention, the emergency speed setting device can be designed in an extremely simple manner; in particular, it is designed more simply than the actual control device or its controller (converter). On the other hand, the invention enables better control over the adjustment speed than the known from the prior art actuation of a battery-supported emergency drive by means of a simple switch, which is essentially based on the fact that the idling speed of the adjustment motor is essentially independent of the armature voltage.

The invention makes use of the knowledge that generally only small currents flow in the shunt winding. There is therefore only a small amount of circuitry required to change the flow caused by the tributary winding. In particular, passive components (for example series resistors) or only very simple active components such as a semiconductor switch (which is much simpler and more interference-free than a converter) can be sufficient. Thus, to increase the speed, a flux reduction can take place by reducing the current through the shunt winding; corresponding to the speed reduction, the flux can be increased with a split shunt winding. In particular, the emergency speed setting device is designed to act exclusively by changing the excitation of the shunt winding. A complex and fault-prone converter, as typically provided in the regular control device, is not required. Thanks to the invention, the emergency speed setting device can therefore be designed without a converter. The variable displacement motor is typically a DC motor.

By placing it on the river, the invention thus achieves, in a strikingly simple manner, a robust control of the speed of the adjusting motor in emergency operation that is completely independent of the regular control device, specifically with the simplest of means. This not only keeps costs low, but also increases operational reliability. The invention is also well suited for retrofitting.

The shunt winding is preferably designed to be divided and connected to the emergency speed setting device in such a way that the magnetic flux is increased by switchable electrical splitting of the shunt winding into divided windings in order to lower the Speed, preferably by connecting the split windings in parallel. A change in the flux of the shunt winding, in particular an increase, can thus be achieved without additional windings and in particular without additional installation space. Appropriately, switches and / or diodes are provided for the switchable splitting of the shunt winding. The provision of a diode for connecting the two parts of the shunt winding is particularly useful. A switch can thus be saved.

Alternatively or additionally, a plurality of switchable series resistors can be provided for the shunt winding to increase the speed, which series resistors are configured so that different current flows are set through the shunt winding depending on the switching state, preferably in multiple stages. In this way, with little additional effort, in particular a multi-stage reduction in the flux through the shunt winding can be achieved, to be precise with passive components alone.

Alternatively or additionally, it can also be provided that the shunt winding is designed for a reduced nominal voltage. A reduced nominal voltage is understood here to mean that the voltage for which the shunt winding is designed (nominal voltage) is lower than the voltage used to operate the adjusting motor, in particular than the nominal voltage for the armature circuit of the adjusting motor. The correspondingly reduced voltage can expediently be obtained by a reference resistor which is preferably connected in series. In this way, a reduced stress level can be achieved in a simple manner. This embodiment with reduced nominal voltage offers the advantage that not only a reduction in the flux of the shunt winding can be achieved in a simple manner, namely by reducing the voltage effectively applied to the shunt winding, but also an increase in the flux of the shunt winding. This is done by applying a voltage to the shunt winding that is higher than the reduced nominal voltage, but still below the actual operating voltage. This "higher" voltage can thus also be obtained from the operating voltage simply through a series resistor. Thanks to this trick, the actually bidirectional function of increasing or decreasing the voltage acting on the shunt winding can be converted into a unidirectional function, namely always a decrease, albeit to a different degree. This results in a maximum of flexible adjustability with a minimum of effort. The adaptation of the shunt winding to a reduced nominal voltage can take place in particular by reducing the number of turns, increasing the cross section, reducing the resistance of the winding and / or designing it for a higher current. Overall, this can expediently be carried out in such a way that no larger winding space is required and thus no additional installation space is required.

It is particularly useful if, in addition to the reference resistor, switchable additional resistors are provided in groups to the reference resistor. A finely graded adjustment of the voltage reduction acting on the shunt winding can thus be achieved. It is particularly useful here if one of the groups is connected to increase the total resistance and another of the groups is connected to reduce the total resistance. The total resistance is understood here to mean the total resistance resulting from the reference resistance on the one hand and the respectively connected additional resistances on the other hand.

In a particularly expedient embodiment, a step-up / step-down converter can be provided, which is connected upstream of the shunt winding. The step-up / step-down converter preferably has at least one active switching element for stepping up and / or one active switching element for stepping down. This enables the voltage for the shunt winding to be essentially freely adjusted in a simple manner. The gradation associated with series resistors can thus be effectively avoided. Since such a step-up / step-down converter can also be made very simply, with at least only one active switching element, at least one active component is required, but this is offset by the considerable advantage that overall there is a significant simplification of the structure. Thanks to the small number of components, such a simple structure is usually also a robust structure and therefore extremely fail-safe. Such a controller is much less complex than a commercially available converter, and for this reason alone is significantly better in terms of its reliability.

The boost / buck converter is advantageously designed to be divided and its first part is connected to a first part of the shunt winding and its second part is connected to the second part of the shunt winding. In this way, an appropriate combination of the advantages of the split design of the shunt winding with the simple basic concept of the boost / buck converter can be achieved. It is particularly useful if the parts the shunt winding are connected by means of a series resistor, and preferably with a diode. A switch connecting or disconnecting the two parts can thus be saved, and the series resistor also enables a flux reduction in the simplest way (the flux increase is achieved by the actuator).

In a particularly preferred embodiment, the

Boost / buck converter combined with a shunt winding designed for a reduced nominal voltage. In this case, it is sufficient if the step-up / step-down converter is designed solely for step-down, and a bidirectional functionality of increasing and decreasing the flow can still be achieved with a simplified structure.

A double-ended motor can preferably be provided as the adjusting motor. However, this is not absolutely necessary, a shunt motor is sufficient. However, the design as a double-wound motor offers the advantage that the shunt winding and its wiring can be optimized solely for the emergency operation function according to the invention. It is preferably provided that the speed adjustment takes place exclusively via the shunt winding in emergency operation.

The invention also extends to a wind power installation comprising a rotor with adjustable blades, a generator driven by the rotor for generating electrical power and an adjusting device for the blades, as described above. For a more detailed explanation, reference is made to the description above.

Furthermore, the invention extends to a corresponding method for the operation of the rotor blade adjustment device or the wind power installation, reference being made to the above description to avoid repetitions for a more detailed explanation of the procedure

The invention is explained in more detail below with reference to the accompanying drawings by way of example using practical embodiments. Show it:

1 shows a schematic overall view of a wind energy installation with a rotor blade adjustment device according to the invention;

2a, b are circuit diagrams for an adjusting motor with a shunt winding for a rotor blade of the wind energy installation according to FIG. 1; 3a-c embodiments with series resistors for reducing the flux of the shunt winding;

4a, b, embodiments with switches for dividing the shunt winding to increase flux;

5a-c show a further embodiment with a reduced nominal voltage and with resistors for lowering / increasing the flux of the shunt winding;

6 shows a further embodiment with a step-up / step-down converter for reducing / increasing the flow;

7 shows a further embodiment with a split shunt winding and with

Series resistor;

8 shows diagrams with voltage and current profiles for the embodiment according to FIG. 7;

9 shows a further embodiment with a shunt winding set to a reduced nominal voltage and with a step-down converter;

10 shows an exemplary control structure for the embodiment according to FIG. 9;

and

11 diagrams with voltage and current profiles for the embodiment according to FIG. 9.

FIG. 1 shows an exemplary embodiment for a wind energy installation provided with a rotor blade adjustment device according to the invention, which is designated in its entirety by the reference number 1. It comprises a tower 10 as a substructure. At its upper end, a gondola 11 is arranged pivotably in a horizontal plane (azimuth plane). A wind rotor 12 is rotatably arranged on one end face of the nacelle 11. It comprises a plurality of rotor blades 13, which are arranged in a hub 14 of the wind rotor 12 so as to be adjustable with respect to their setting angle β. The wind rotor 12 drives a (not shown) Rotor shaft to a generator 15, which cooperates with a converter 16 to convert the mechanical power supplied by the wind rotor 12 into electrical power, which is output via a connection line 10 from the wind turbine.

A blade control module 2 is arranged in the rotor hub 16 and is designed to adjust the setting angle β of the rotor blades 13. The blade control module 2 comprises an adjusting motor 20 which is controlled by a control unit 21 by means of an actuator 22. The actuator 22 is typically designed as a converter.

In the variant shown in FIG. 2a), the adjusting motor 20 is designed as a direct current double-wound motor 20 '. This comprises an armature circuit 3 with an armature resistor RA 31 and an armature inductance LA 32 and a series winding 33 with a series winding inductance LRF 34 and a series winding resistor RRF 35. A shunt winding 5 is also provided, which has a shunt inductance LNF 54 and a shunt resistor RNF 53. The supply takes place by means of a battery 29, which can be switched on via a contactor 23 in emergency operation.

In the variant shown in FIG. 2b), the adjusting motor 20 has a simplified design, namely as a pure direct current shunt motor. Like the embodiment according to FIG. 2a), it has an armature circuit 3 and a shunt winding 5, but no series winding 33. Otherwise, the design corresponds to that shown in FIG. 2a), with the same components having the same reference numerals.

A first embodiment of the invention provides for the flux to be reduced in the shunt field generated by the shunt winding 5 by means of one or more switchable series resistors 7. A first embodiment of an emergency speed setting device 4 suitable for this is shown in FIG. The variant shown in FIG. 3a) additionally includes a series resistor 71 for the shunt winding 5, which can be switched on via a switch 71 '. The regular ground path of the shunt winding 5 is switched via a switch 70 '. By operating the switch 71 '(and opening the switch 70'), the current flow through the shunt winding 5 is reduced and a flux lowering is thereby achieved. An increase in speed can thus be achieved. It should be noted that in this embodiment the switch 71 'is omitted and can be replaced by a bridge; The current flow through the shunt winding 5 can be reduced simply by opening the switch 70 ′. In Figure 3b) and 3c) two further variants are shown, each having series resistors 72 and 73, which are switched accordingly via additional switches 72 'and 73'. In the variant according to Figure 3b), the series resistors 71, 72, 73 are graduated in size, the resistance value of the series resistor 71 is smaller than the resistance value of the series resistor 72 and which in turn is smaller than the resistance value of the series resistor 73 Degree of the desired reduction then exactly one of the switches 71 ', 72' or 73 'actuated. This can result in a gradation of the current flow through the shunt winding 5 and accordingly different increases in speed can be achieved. The variant according to FIG. 3c) differs only in that several of the switches 71 ', 72' and 73 'can also be actuated at the same time, and thereby a gradation is achieved. Here, too, it applies that, for the sake of simplicity, the stage with the greatest reduction in the current flow, that is to say that contains the greatest resistance (in this case that is in each case the resistor 73 '), can be implemented without a switch and instead be permanently connected by a bridge.

Reference is now made to FIG. 4. Reference is first made to FIG. 4a). An embodiment is shown there in which the shunt winding 5 is divided into two parts 51, 52. Each of the parts has its own partial inductance 54 ‘and its own partial resistance 53‘. Several switches 75, 76, 77 are provided via which the two parts 51, 52 can be switched on individually and switched in parallel and in series. If only the switch 77 is closed, then the two parts 51, 52 are connected in series, so that they basically behave like an original shunt winding 5. If, however, the switch 77 is open and instead the switches 75, 76 are closed; both parts 51, 52 are connected in parallel so that there is an increase in flow. This reduces the speed of the adjusting motor 20. In the variant shown in FIG. 4b), the switch 77 is replaced by a diode 78 which connects the two parts 51, 52 of the shunt winding 5 in series. When the switches 75, 76 are open, the current flows through both parts 51, 52 of the shunt winding 5, i. H. there is no increase in the flow. If, on the other hand, the two switches 75, 76 are closed, the two parts 51, 52 are effectively connected in parallel, so that an increase in the flux through the shunt winding 5 as a whole and thus a reduction in speed results.

FIG. 5 shows a variant in which the shunt winding 5 is designed for a reduced nominal voltage UNF _red . In order to reduce the supply voltage UB to the now reduced nominal voltage UNF _{red of} the shunt winding 5 is a specially designed reference resistor 74 is provided and connected in series with the shunt winding 5 (in the illustrated embodiment to ground). The reference resistor 74 is dimensioned in such a way that at the rated current through the shunt winding 5, such a voltage drop U _A occurs that, based on the operating voltage UB of the adjusting motor 20 applied to the armature circuit 3, the voltage drops just enough that it reaches the reduced rated voltage UNF _red . This is shown in Figure 5a). In order to be able to bring about a change in the current flow through the shunt winding 5, further branches are preferably connected in parallel to the reference resistor 74, as shown in FIG. 5b), which have series resistors 70, 72 and a switch 70 ', 72' each. A switch 74 ′ is also provided for the branch with the reference resistor 74. In this case, the series resistor 70 is dimensioned such that it is somewhat smaller than the reference resistor 74 and the resistor 72 is dimensioned such that it is somewhat greater than the reference resistor 74. Thus, depending on which of the switches 70 ', 72' or 74 'is actuated, an increase or reduction in the current flow through the shunt winding 5 can be achieved. Thus, simply by providing series resistors with switches, an increase or reduction in the speed of the adjusting motor 20 can be brought about. As shown in FIG. 5c), additional branches with series resistors 71, 73 and corresponding switches 71 ', 73' can be provided in order to achieve a finer gradation with regard to flux increase or flux reduction of the shunt winding 5 and thus a speed reduction or speed increase of the adjustment motor 20 to reach.

In a further embodiment shown in Figure 6, the increase or reduction of the flux through the shunt winding 5 takes place not by means of series resistors, but through the use of a step-up / step-down converter 8. This is with its input to the voltage supply UB and its output to the Shunt winding 5 to closed. The step-up / step-down converter 8 can be designed in a simple manner and has only a single active switch 81, 82 (for example an IGBT each) for stepping down or stepping up the output voltage. The switch 81 is arranged at the input of the step-up / step-down converter 8 and is connected in series with a diode 83 connected in the reverse direction. A capacitor 80 is also connected to the input. This switch 81 is used to step down the output voltage. The voltage generated in this way is dissipated via an inductance 85 connected to the node between switch 81 and the cathode of diode 82. The second switch 82 is arranged at the other end of the inductance 85 and switches to ground; Furthermore, a diode 84 is switched in the forward direction and leads to the output of the step-up / step-down converter 8. A second capacitor 85 is also connected to the output. By pulsing the first switch 81 (without Confirming the second switch 82) a reduced voltage is generated, which is passed through by the diode 84 to the output of the step-up / step-down converter 8. If, on the other hand, the first switch 81 is switched on in a stationary manner and the second switch 82 is actuated in a pulsed manner instead, the voltage at the output of the step-up / step-down converter 8 is increased using the inductance 85 as a charging choke and the second capacitor 85 as a storage capacitor. The shunt winding 5 is connected to the output. In this way, depending on the voltage generated by the step-up / step-down converter 8, the current flow through the shunt winding 5 can be changed and the flow generated by it can be controlled, whereby a speed increase or speed decrease can be controlled accordingly.

The embodiments can also be combined with one another. Thus, the step-up / step-down converter 8 shown in FIG. 6 can also be used in the case of a split design of the shunt winding 5 corresponding to the embodiment according to FIG a reverse-biased diode 83 'and 84'. The first part 51 of the shunt winding 5 is supplied by the first switch 8T. Correspondingly, the second part 52 of the shunt winding 5 is led to ground via the second switch 82 ‘. The first part 51 and the second part 52 are connected to one another via a series-connected combination of a forward-biased diode 86 and a resistor 87. Using the second switch 8T, the voltage U1 via the first part 51 of the shunt winding 5 and thus the Current flow 11 can be set and the voltage U2 across the second part 52 of the shunt winding 5 and thus the current flow I2 can be set accordingly by means of the second switch 82 '. It should be noted that resistor 87 is optional. If it does not apply, however, no flux reduction (and thus no increase in speed) is possible, only an increase in the flux (and thus a decrease in speed). It should also be noted that the number of windings of the two partial windings 51, 52 is preferably identical in order to avoid undesirable transformer effects.

The resulting voltage and current curves are shown in FIGS. 8a) to f). FIG. 8a) shows the switching on of the supply voltage at time t equal to 0.1s. A high-frequency carrier signal is present all the time, as shown by the oscillation in FIG. 8b). A control signal for the step-up / step-down converter 8 for the output voltage to be output by it is shown in FIG. 8b) with the ramp signal shown in a solid line. The active switches 81, 82 controlled in this way each set the same voltage U1 on the first part 51 and U2 on the second part 52 the shunt winding 5 a. This is shown in Figure 8c). Both voltages are identical so that the curves are superimposed. The sum of the two voltages is shown in FIG. 8d). The currents I1 and I2 that result in each case are shown in FIG. 8e), the two currents here also being identical and their curves therefore superimposed. The flux of the shunt winding 5 or of its first part 51 finally resulting from the activation of the step-up / step-down converter 8 is shown in FIG. 8f). The lower curve represents the flux through the first part 51 of the shunt winding 5 (the flux through the second part 52 is identical), and the total resulting flux through the shunt winding 5 is represented by the upper of the two curves. It can be seen that the change in the control signal (see the ramp-like increase in Figure 8b) results in a corresponding change in the voltage across the respective winding parts 51, 52 (see Figure 8c), the current flowing through them (see Figure 8e) and finally the flux can be set by the shunt winding 5 or its part 51 (see Figure 8f). A corresponding speed setting of the adjusting motor 20 can thus take place.

A further simplification is shown in FIG. It is based on the embodiment according to FIG. 3a) with a shunt winding designed for a reduced nominal voltage using a simplified controller, namely a pure buck converter 8 '. It only comprises an active switch 81, a blocking diode 83 arranged in series and connected in the reverse direction, and an input capacitor 80. An output voltage of the buck converter 8 'is thus reduced so far that it corresponds to the reduced nominal voltage UNF _{red of} the shunt winding 5 according to the embodiment shown in Figure 3 fits. By changing the control signal CTL of the buck converter 8 ', starting from the reduced nominal voltage UNF _red, an increase or decrease in the output voltage can thus be achieved in the simplest way. Functionally, this embodiment corresponds to the embodiment according to FIG. 5b or 5c, but without the need for a large number of switching devices and series resistors. You can book the advantages of constructive simplicity and stepless adjustment of the output voltage and thus the flux reduction / increase and thus increase or reduction of the speed for yourself.

An exemplary embodiment for a possible speed controller for this is shown in FIG. It is denoted in its entirety with the reference number 9 and comprises two inputs for a reference speed nref and the actual speed n, which are applied to a differential element 90. The actual output is via a switch 91 Control core connected to a PI control block 93. The signal output by the control block 93 is connected to an input of a summing member 95 via a limiting member 94, a base signal for the speed being added via another input of the summing member 95. The resulting sum signal is output as a control signal for the pulse width modulation of the actuator 8, 8 '. The switch 91 is actuated by a delay element 92. This is designed to activate the controller with its controller block 93 only after a delay. In this way, undesired behavior of the regulator 9 during the time required for the field current of the shunt winding 5 to run up can be avoided. The resulting courses are shown in FIG. In Figure 11a) the load torque of the adjusting motor 20 is shown (the zero line being highlighted by a bold horizontal line. In Figure 11b) the reference speed nref and the actual speed n are shown. The delayed start of the control 9 brought about by the delay element 92 is visualized in FIG. 11c) (jump from off to on at t = 0.75 sec.). The output value CTL of the speed control (see FIG. 10) finally resulting from the activity of the regulation and the base value are shown in FIG. 11 d) as a normalized variable. The pulse signal for controlling the active switches and the low-pass signal averaged therefrom are shown in FIG. 11e). The resulting current through the shunt winding 5 is shown in FIG. 11f) (as a standardized variable). The armature voltage Ua and the induced voltage of the motor Ui are shown in FIG. 11g), and the armature current Ia ultimately resulting therefrom is shown in FIG. 11h).

Claims

1. Adjusting device for at least one rotor blade (13) of a wind rotor (12) one

Wind power plant, with a blade control module (2) and an adjusting motor (20) which is connected to an electrical power supply and actuates the rotor blade (13) to change its angle of attack, the blade control module (2) comprising a control device which is used in normal operation Adjusting motor (20) actuated in a controlled manner, and in emergency operation the adjusting motor (20) can be actuated independently of the control device, the adjusting motor (50) having a shunt winding (5), characterized in that, in addition to the control device, an emergency speed adjusting device for the adjusting motor (20) is provided, which is designed to increase or decrease a flux through the shunt winding (5) in emergency operation depending on a desired change in the speed of the adjusting motor (20).

2. Adjusting device according to claim 1, characterized in that the emergency speed adjusting device is designed to act exclusively by changing an excitation of the shunt winding (5).

3. Adjusting device according to claim 1 or 2, characterized in that a split shunt winding is provided and connected to the emergency speed control device that by switchable electrical splitting of the shunt winding (5) into split windings (51, 52) whose magnetic flux is increased to Lowering the speed, preferably by connecting the split windings (51, 52) in parallel, the switchable splitting preferably taking place by means of at least one switch (75, 76, 77) and / or at least one diode (78).

4. Adjusting device according to one of the preceding claims, characterized in that a plurality of switchable series resistors (71, 72, 73) for the Ne- Shunt winding (5) is provided to increase the speed, which are configured so that, depending on the switching state, different current flows are set through the shunt winding (5), preferably in multiple stages.

5. Adjusting device according to one of the preceding claims, characterized in that the shunt winding (5) is designed for a reduced nominal voltage (UNFred), wherein a reference resistor (74) is preferably connected in series to adapt to an operating voltage.

6. Adjusting device according to claim 5, characterized in that switchable

Additional resistors are provided in preferably two groups to the reference resistor (74), one of the groups being connected to increase the total resistance and another of the groups being connected to decrease the total resistance.

7. Adjusting device according to one of the preceding claims, characterized in that a step-up / step-down converter (8) is provided, which is connected upstream of the shunt winding (5).

8. Adjusting device according to claim 7, characterized in that the step-up / step-down converter (8) comprises at least one active switching element (82) for stepping up and / or an active switching element (81) for stepping down.

9. Adjusting device according to claim 7 or 8, characterized in that the

The step-up / step-down converter (8) is divided and connected with its first part to a first part (51) of the shunt winding (5) and with its second part (52) to the second part of the shunt winding (5).

10. Adjusting device according to claim 9, characterized in that the two

Parts (51, 52) of the shunt winding by means of a diode (86), and preferably with a series resistor (87), are connected.

11. Adjusting device according to one of the preceding claims, characterized in that the adjusting motor (20) is designed as a double-ended motor.

12. Adjusting device according to claim 11, characterized in that the emergency speed control acts exclusively on the adjusting motor via the precipitation winding in emergency operation.

13. Wind energy installation comprising a rotor (12) with adjustable rotor blades

(13), a generator (15) driven by the rotor for generating electrical power and an adjustment device for at least one rotor blade (13) of a wind rotor (12) of a wind turbine, with a blade control module (2) and an adjustment motor (20) which is connected to an electrical power supply and actuates the rotor blade (13) to change its angle of attack, the blade control module (2) comprising a control device (21) which actuates the adjustment motor (20) in a controlled manner in normal operation, and the adjustment motor in emergency operation (20) can be operated independently of the control device (21), the adjusting motor (50) having a shunt winding (5), characterized in that in addition to the control device (21) an emergency speed adjusting device (4) of the adjusting motor (20) is provided which is designed for this purpose, a flow through the shunt winding (5) depending on a desired speed change of the Vers control motor (20) to increase or decrease.

14. Method for operating an adjusting device for at least one rotor blade

(13) of a wind rotor (12) of a wind power plant, with a blade control module (2) and an adjusting motor (20) which is connected to an electrical power supply and operates the rotor blade (13) to change its angle of attack, the blade control module (2) comprises a control device which actuates the adjusting motor (20) in a controlled manner in normal operation, and in emergency operation the adjusting motor (20) can be actuated independently of the control device, the adjusting motor (50) having a shunt winding (5), characterized in that im Emergency operation an emergency speed adjustment of the adjusting motor (20) takes place, wherein in emergency operation a flux through the shunt winding (5) is increased or decreased depending on a desired change in speed of the adjusting motor (20).

15. The method according to claim 14, characterized in that an adjusting device according to one of claims 2 to 13 is used.