DE102018009230A1 - Method and system for operating a wind turbine - Google Patents

Abstract

In a method according to the invention for operating a wind power plant, which has a rotor (130) which can be rotated about a rotor axis (R) with at least two rotor blades (30) which can be individually adjusted about its blade axis (B) and a tracking drive (20) for wind tracking of the rotor about a yaw axis (G), blade angles of the rotor blades are adjusted in a tracking operating mode about their blade axis to support a wind tracking movement by the tracking drive (S40, S60), an amplitude of this blade angle adjustment being reduced by or to a predetermined value (S55) if a yaw rate of the Rotor lies around the yaw axis in a predetermined reduction speed range, which has a lower reduction speed limit; and / or increased by or to a predetermined value if a yaw rate of the rotor about the yaw axis lies in a predetermined increase speed range which has an upper increase speed limit.

Description

The present invention relates to a method and system for operating a wind energy installation and a computer program product for carrying out the method.

In wind turbines that have a rotor with rotor blades that can be rotated about a horizontal rotor axis, it is known per se to use a tracking drive to rotate the rotor about a vertical yaw axis in order to reduce a deviation between its rotor axis and a varying wind direction (“wind tracking”) .

In particular, with increasing rotor diameters, the loads on such tracking drives increase.

The object of the present invention is to improve the operation of a wind turbine.

This object is achieved by a method with the features of claim 1. Claims 6, 7 provide protection for a system or computer program product for carrying out a method described here. The subclaims relate to advantageous further developments.

According to one embodiment of the present invention, a wind energy installation has a rotor which, in one embodiment, in particular in a nacelle, is rotatable (mounted) about a rotor axis.

In one embodiment, the rotor is coupled to a generator for converting wind energy into electrical energy or has a generator, in one embodiment the wind energy installation is provided for feeding electrical energy into a power grid, in particular it is set up or is used for this purpose.

According to an embodiment of the present invention, the rotor has at least two, in particular at least three, rotor blades, which or their blade angles, in particular with the aid of a blade adjustment device which is motorized, in particular electromotive, and / or hydraulic, individually or separately around their (respective) blade axes are adjustable or rotatable or are adjusted or rotated, in one embodiment (also) during operation or with the rotor rotating about its rotor axis.

According to one embodiment of the present invention, the wind energy installation has a tracking drive which, in a tracking operating mode, adjusts the rotor or its rotor axis, in particular the nacelle relative to a tower on which it is rotatably arranged, about a yaw axis in such a way or with the proviso that a deviation between the rotor axis and a wind direction recorded, or predicted, in one embodiment, in particular current wind direction, in particular in a horizontal plane, is reduced (“wind tracking of the rotor”) or is provided for this, in particular is set up or used.

In one embodiment, this can improve the conversion of wind energy into mechanical or electrical power by the wind energy installation.

In an embodiment with a direction of gravity, the yaw axis encloses an angle which is at most 30 °, in particular at most 15 °. In one embodiment, the yaw axis is, at least substantially, vertical (aligned).

Additionally or alternatively, the rotor axis forms an angle with one or the direction of gravity, which is at least 60 °, in particular at least 75 °, and / or at most 120 °, in particular at most 105 °. In one embodiment, the rotor axis is at least substantially horizontally (aligned), in a further development (slightly) inclined against the horizontal, preferably by at least 2 ° and / or at most 10 °.

Additionally or alternatively, the rotor axis in one embodiment forms an angle with the yaw axis which is at least 60 °, in particular at least 75 °, and / or at most 120 °, in particular at most 105 °. In one embodiment, the rotor and yaw axes are at least essentially perpendicular to one another.

In one embodiment, this can (further) improve the conversion of wind energy into mechanical or electrical power by the wind energy installation.

In one embodiment, the tracking drive has one or more electric and / or hydraulic motor (s) for electromotive or hydraulic wind tracking of the rotor or nacelle around the yaw axis or opposite the tower, in one embodiment with the aid of a single-stage or multi-stage transmission . In one embodiment, the wind energy installation has at least one, in particular mechanical, electrical and / or hydraulic, parking brake for fixing an (angular) position of the rotor or the nacelle around the yaw axis or with respect to the tower.

According to an embodiment of the present invention, the blade angles of the rotor blades are changed by their (respective) Blade axis adjusted in such a way or with the proviso that a wind tracking movement is supported by the tracking drive.

In one embodiment, the blade angles are cyclically or periodically adjusted with the speed of the rotor about its rotor axis (“rotor speed”), in one embodiment the individual (amplitudes of this) blade angle adjustment (s) of the individual rotor blades are mutually phase-shifted about the rotor axis, in a version by a constant angle, which in one version is equal to 360 ° divided by the number of rotor blades.

This is based on the idea that such a blade angle adjustment can aerodynamically induce a torque about the yaw axis, which torque can advantageously be used to support the wind tracking movement by the tracking drive.

In this way, loads of the tracking drive can be reduced in one embodiment, in particular larger wind power plants or constant wind power plants with smaller tracking drives (slast) can therefore be operated with constant tracking drives.

According to an embodiment of the present invention, the blade angles of the rotor blades are adjusted about their (respective) blade axis to support a wind tracking movement by the tracking drive when the wind power installation is operated in the tracking operating mode, an amplitude of this blade angle adjustment, in particular with respect to a reference value, around or on a predetermined (first reduction) value is reduced if a yaw rate of the rotor, in particular its rotor axis, about the yaw axis, in particular in terms of magnitude or signed, lies in a predetermined (adjustable) design (first) reduction speed range which is a ( first) has the lower speed limit, in particular is limited by this (down).

Additionally or alternatively, according to an embodiment of the present invention for or when operating the wind energy plant in the tracking operating mode, the blade angles of the rotor blades are adjusted about their (respective) blade axis to support a wind tracking movement by the tracking drive, an amplitude of this blade angle adjustment, in particular with respect to or the reference value, by or to a predetermined (first increase) value, if a yaw rate of the rotor about the yaw axis, in particular in terms of magnitude or signed, is within a predetermined (adjustable) embodiment (first) increase speed range that is one Has (first) upper increase speed limit, in particular is limited by this (up).

In one embodiment, the amplitude of the blade angle adjustment to support a wind tracking movement by the tracking drive has the reference value determined in one embodiment, in particular constant, in particular adjustable, or variable, if the yaw rate is below the (first) reduction speed range or the (first) ) lower reduction speed limit and / or above the (first) increase speed range or the (first) upper increase speed limit, in particular within a normal speed range, and the reduced (first reduction) value, if the yaw rate is within the (first) reduction speed range and / or the (first increase) value, in contrast, if the yaw rate is within the (first) increase speed range.

This is based in particular on the idea that such a step-like reduction or increase in one embodiment can achieve stable (re) s operating behavior while at the same time advantageously converting wind energy into mechanical or electrical power by means of the wind energy installation.

In one embodiment, the amplitude of the blade angle adjustment in order to support a wind tracking movement is gradually reduced or downgraded by the tracking drive to the (first) reduction value if the yaw rate, in particular in terms of amount or sign, exceeds the (first) lower reduction speed limit . Additionally or alternatively, the amplitude of the blade angle adjustment in order to support a wind tracking movement by the tracking drive is gradually increased or upgraded in one embodiment to or to the (first) increase value if the yaw rate, in particular in terms of amount or sign, increases the (first) upper increase - Speed limit is below.

This is based in particular on the idea of reducing the support of a wind tracking movement induced by the tracking drive by the blade angle adjustment in the case of a (too) high yaw rate or increasing the support of a wind tracking motion induced by the tracking drive on the blade angle adjustment at a (too) low yaw rate.

In one embodiment, no or at least one reducing speed range, in particular at least two reducing speed ranges, and / or at most four reducing speed ranges, or in a preferred embodiment exactly one reducing speed range or exactly two reducing speed ranges, is or are provided in the tracking operating mode , for which the amplitude of the blade angle adjustment is (in each case) speed range-specific or reduced by or to the corresponding (speed range-specific reduction) value.

Additionally or alternatively, in an embodiment in the tracking operating mode, no or at least one increase speed range, in particular at least two increase speed ranges, and / or at most four increase speed ranges, in a preferred embodiment exactly one increase speed range or exactly two increase speed ranges. Speed ranges are provided for which the amplitude of the blade angle adjustment is (in each case) speed range-specific or increased by or to the corresponding (speed range-specific increase) value.

This is based in particular on the idea that such a very limited speed range or number of steps (in number) in one embodiment enables particularly stable operating behavior to be achieved with the wind energy installation at the same time advantageously converting wind energy into mechanical or electrical power. Additionally or alternatively, in one embodiment, sensors and / or operational management can be designed to be robust and / or existing wind turbines can be advantageously retrofitted, preferably without or with minor hardware changes, and / or the effects in the event of a fault are limited and / or to be easily mastered.

Accordingly, in an embodiment in the tracking operating mode, the blade angles are adjusted, the amplitude of the blade angle adjustment being reduced by or to a predetermined (second reduction) value in support of a wind tracking movement by the tracking drive if the yaw rate, in particular in terms of amount or sign, is reduced to a predetermined value , in an embodiment adjustable second reduction speed range, which has a second lower reduction speed limit, in particular limited by this (down), and / or is increased by or to a predetermined (second increase) value if the Yaw rate, in particular in terms of amount or sign, lies in a predetermined, adjustable, second increase speed range, which has a second upper increase speed limit, in particular limited by this (down).

In one embodiment, the first or second reduction speed range can be open on one side or upwards or have a (first or second) upper reduction speed limit or be limited by this (up). Additionally or alternatively, in one embodiment, the first or second increase speed range can be open on one side or downwards or have a (first or second) lower increase speed limit or be limited by this (downwards). In one embodiment, the second lower speed limit is equal to the first upper speed limit and / or the second upper speed limit is equal to the first lower speed limit. In one embodiment, the first or second upper reduction speed limit can be equal to a maximum possible or permissible yaw rate of the rotor about the yaw axis or also (theoretically or mathematically) infinitely or, as already mentioned, the first or second reduction speed range can be open at the top . Additionally or alternatively, in one embodiment the first or second lower increase speed limit may be zero or negative. In one embodiment, this also advantageously covers (rare) cases in which the rotor is pressed in a direction opposite to the desired tracking movement, for example due to unexpected turbulence or the like. Additionally or alternatively, in one embodiment, the (first) upper increase speed limit is smaller than the (first) lower reduce speed limit, in particular the (first) lower reduce speed limit and / or the (first) upper increase speed limit Limit the normal speed range in which a reference value of the amplitude of the blade angle adjustment to support a wind tracking movement by the tracking drive is neither reduced nor increased.

In one embodiment, the amplitude of the blade angle adjustment is reduced by the first reduction value when the first lower reduction speed limit is exceeded and, when the (higher) second lower reduction speed limit is exceeded, reduced again by the same or a different reduction value. In one embodiment, the amplitude of the blade angle adjustment is reduced to the first reduction value when the first lower reduction speed limit is exceeded and is reduced to the second reduction value which is smaller than the first reduction speed when the (higher) second lower reduction speed limit is exceeded. Is worth.

In one embodiment, the amplitude of the blade angle adjustment is reduced by the first increase value when the first upper increase speed limit is undershot and once again fall below the (lower) second upper increase speed limit by the same or a different increase value. In one embodiment, the amplitude of the blade angle adjustment is reduced to the first increase value when the first lower increase speed limit is undershot and is reduced to the second increase value when the (lower) second lower increase speed limit is undershot, which is less than the first increase value. Is worth.

In one embodiment, the first and / or second reduction and / or increase speed range and / or the normal speed range (in each case) extends over at least 0.05 ° per second [° / s], in particular at least 0.1 ° per Second, in one version at least 0.2 ° per second.

As a result, in one version, in particular in a combination of two or more of the above-mentioned versions, particularly stable operating behavior can be achieved with the wind power plant advantageously converting wind energy into mechanical or electrical power.

• - Ermitteln eines Windnachführbedarfs, in einer Ausführung mittels Ermitteln, insbesondere messtechnisches Erfassen, einer Abweichung zwischen einer, insbesondere aktuellen oder gemittelten, Windrichtung und der Rotorachsrichtung, insbesondere deren horizontaler Komponente;
• - Ermitteln der Amplitude der Blattwinkelverstellung zur Unterstützung der Windnachführbewegung durch den Nachführantrieb, insbesondere des Referenzwertes, in einer Ausführung auf Basis einer insbesondere empirisch und/oder mithilfe einer Simulation, vorgegebenen, insbesondere abgespeicherten und/oder einstellbaren, Abbildung von Windnachführbedarfswerten auf einen oder mehrere Blattwinkelverstellungsamplitudenwerte, insbesondere mithilfe eines Kennfeldes oder dergleichen;
• - Einstellen der individuellen Blattwinkel der Rotorblätter auf Basis dieser ermittelten Amplitude
• - Ermitteln, insbesondere messtechnisches Erfassen oder Prognostizieren, eines Ist-Wertes der Giergeschwindigkeit des Rotors um die Gierachse; wenigstens einen der Schritte:
• - stufenförmiges Reduzieren der ermittelten Amplitude, falls der Ist-Wert eine oder mehrere vorgegebene, insbesondere einstellbare (untere Reduzier-)Geschwindigkeitsgrenzen überschreitet; und/oder
• - stufenförmiges Erhöhen der ermittelten Amplitude, falls der Ist-Wert eine oder mehrere vorgegebene, insbesondere einstellbare (obere Erhöhungs-)Geschwindigkeitsgrenzen unterschreitet; sowie den Schritt:
• - (gegebenenfalls) Ein- bzw. Verstellen der individuellen Blattwinkel der Rotorblätter auf Basis dieser ermittelten und um eine oder mehrere Stufen reduzierten bzw. erhöhten Amplitude auf.

In one embodiment, the method has the steps, chronological or sequential in one embodiment:

• - Determining a wind tracking requirement, in one embodiment by means of determining, in particular measuring, a deviation between a, in particular current or averaged, wind direction and the rotor axis direction, in particular its horizontal component;
• - Determining the amplitude of the blade angle adjustment to support the wind tracking movement by the tracking drive, in particular the reference value, in an embodiment based on an, in particular empirically and / or with the aid of a simulation, predetermined, in particular stored and / or adjustable, mapping of wind tracking requirement values onto one or more blade angle adjustment amplitude values , in particular with the aid of a map or the like;
• - Setting the individual blade angle of the rotor blades based on this determined amplitude
• - Determining, in particular metrological recording or forecasting, an actual value of the yaw rate of the rotor about the yaw axis; at least one of the steps:
• - Step-like reduction of the determined amplitude if the actual value exceeds one or more predetermined, in particular adjustable (lower reduction) speed limits; and or
• - Gradually increasing the determined amplitude if the actual value falls below one or more predetermined, in particular adjustable (upper increase) speed limits; as well as the step:
• - (If necessary) adjusting or adjusting the individual blade angles of the rotor blades on the basis of the amplitude determined and reduced or increased by one or more steps.

• - Mittel zum Verstellen von Blattwinkeln der Rotorblätter um ihre Blattachse zur Unterstützung einer Windnachführbewegung durch den Nachführantrieb in einem Nachführbetriebsmodus sowie wenigstens eines von:
• - Mittel zum Reduzieren einer Amplitude dieser Blattwinkelverstellung um oder auf einen vorgegebenen Wert, falls eine Giergeschwindigkeit des Rotors um die Gierachse in einem vorgegebenen Reduzier-Geschwindigkeitsbereich liegt, der eine untere Reduzier-Geschwindigkeitsgrenze aufweist; und/oder
• - Mittel zum Erhöhen einer Amplitude dieser Blattwinkelverstellung um oder auf einen vorgegebenen Wert, falls eine Giergeschwindigkeit des Rotors um die Gierachse in einem vorgegebenen Erhöhungs-Geschwindigkeitsbereich liegt, der eine obere Erhöhungs-Geschwindigkeitsgrenze aufweist.

According to an embodiment of the present invention, a system for operating the wind energy installation, in particular hardware and / or software, in particular program technology, is set up to carry out a method described here and / or has:

• - Means for adjusting blade angles of the rotor blades about their blade axis to support a wind tracking movement by the tracking drive in a tracking operating mode and at least one of:
• Means for reducing an amplitude of this blade angle adjustment by or to a predetermined value if a yaw rate of the rotor about the yaw axis is in a predetermined reduction speed range which has a lower reduction speed limit; and or
• - Means for increasing an amplitude of this blade angle adjustment by or to a predetermined value if a yaw rate of the rotor about the yaw axis lies in a predetermined increase speed range which has an upper increase speed limit.

According to an embodiment of the present invention, the blade angles of the rotor blades are adjusted about their (respective) blade axis to support a wind tracking movement by the tracking drive, or an amplitude of this blade angle adjustment depending on a rotor torque is adjusted about or when operating the wind power plant in the tracking operating mode becomes.

In one embodiment, the amplitude, in particular in terms of amount or signed, is increased from a first to a second value if the rotor torque instead of a first one, in particular in terms of amount or signed, has a larger second value or reduced from a second to a first value if the rotor torque has a smaller first value, in particular in terms of amount or with sign, instead of a second.

This is based in particular on the idea that a torque around the rotor axis in one embodiment is a particularly suitable indicator for adjusting the amplitude of the blade angle adjustment to support the wind tracking movement by the tracking drive, since it reflects the load or load condition of the wind turbine particularly well. For example, higher wind loads generally lead to larger rotor torques and, at the same time, require stronger support of a wind tracking movement induced by the tracking drive through the blade angle adjustment. Additionally or alternatively, in one embodiment, a rotor torque that is already known or already known, in particular for controlling the wind energy installation, can advantageously be used in addition to the blade angle adjustment to support a wind tracking movement by the tracking drive.

Accordingly, in one embodiment, a stable (re) s operating behavior can be achieved with the wind energy installation advantageously converting wind energy into mechanical or electrical power.

In one embodiment, the amplitude of the blade angle adjustment to support a wind tracking movement by the tracking drive is zero or is set or set if the rotor torque, in particular in terms of amount or sign, falls below a predetermined torque limit value, which is greater than zero in one embodiment. In other words, in one embodiment a, in particular cyclical, blade angle adjustment to support the wind tracking movement is suppressed by the tracking drive if or as long as the rotor torque, in particular in terms of amount or sign, falls below a predetermined torque limit value.

This is based in particular on the idea that, in one embodiment, support of a wind tracking movement induced by the tracking drive by the blade angle adjustment is not necessary on the one hand, and on the other hand, suppression of such blade angle adjustment or the reduction or adjustment of its amplitude to zero is one deterioration of the conversion of wind energy into mechanical or electrical power by the wind power installation induced by this blade angle adjustment is avoided and thus a conversion of wind energy into mechanical or electrical power by the wind power installation can be improved.

In one embodiment, the rotor torque is determined on the basis of a torque setpoint, in particular it can be a torque setpoint.

This is based, in particular, on the idea that, in one embodiment, target values are less prone to measurement errors, in particular less noisy, than actual values that are usually measured.

In one embodiment, the rotor torque can be determined indirectly, for example by dividing a power on the rotor shaft or a gearbox or generator shaft coupled to it by a rotational speed of this shaft. In one embodiment, this can improve the determination, in particular simplify it and / or increase its precision. Generally, a rotor torque is understood to mean, in particular, a torque acting on or exerted on the rotor.

According to an embodiment of the present invention, the blade angles of the rotor blades are adjusted about their (respective) blade axis to support a wind tracking movement by the tracking drive for or during operation of the wind power plant in the tracking operating mode, an amplitude of this blade angle adjustment (also) depending on a wind tracking direction of the Rotor is adjusted around the yaw axis.

This is based in particular on the idea that - in particular due to the so-called tilt angle, i.e. as a result of a (slight) inclination of the rotor axis relative to the horizontal, which in one embodiment is at least 2 ° and / or at most 10 ° - even aerodynamically without blade angle adjustment a torque is induced around the yaw axis, which acts in one direction. If the rotor is now to be wind-tracked in this direction or a wind-tracking movement is to be supported by the tracking drive in this direction by means of the blade angle adjustment, this accordingly requires a lower torque about the yaw axis induced by the, in particular cyclical, blade angle adjustment than vice versa in the case of wind tracking (moving). tion in the opposite direction or against the direction in which the torque induced without blade angle adjustment acts around the yaw axis or tries to turn the rotor.

Accordingly, in one embodiment, the amplitude of the blade angle adjustment to support a wind tracking movement is set by the tracking drive in such a way that it is at a first Wind tracking direction and in a second wind tracking direction opposite to this, in particular under otherwise identical (ambient) conditions, have an offset from one another, this offset being constant in one embodiment. In another embodiment, the offset depends on one or the rotor torque, in a further development it is linear. In particular, the offset can thus increase (directly) proportionally with increasing rotor torque in one embodiment. In one embodiment, the offset is or is predefined, in particular set, or predefined, in particular adjustable. Correspondingly, in one embodiment, the offset (then constant during operation) or the dependency on the rotor torque, in particular a proportionality factor between the rotor torque and offset, is predetermined, in particular set, or predetermined, in particular adjustable.

As a result, in one embodiment, a stable (re) operating behavior and / or a particularly advantageous conversion of wind energy into mechanical or electrical power can be realized by the wind energy installation.

According to one embodiment of the present invention, the blade angles of the rotor blades are adjusted about their (respective) blade axis to support a wind tracking movement by the tracking drive, in particular individually and / or cyclically, for or when operating the wind energy plant in the tracking operating mode, the blade angle depending on an amplitude of this blade angle adjustment can also be adjusted by a lead angle in such a way or with the proviso that even with maximum blade angle adjustment to support a wind tracking movement by the tracking drive, a minimum blade angle is (can) be maintained. In this case, a blade angle is at a maximum in one embodiment if the rotor blade has a so-called flag position in which the conversion of wind energy into mechanical or electrical power is minimal. Correspondingly, a minimum blade angle denotes a maximum permissible adjustment away from the flag position or towards a position in which the conversion of wind energy into mechanical or electrical power is at a maximum.

This is based in particular on the idea that the blade angle adjustment to support a wind tracking movement by the tracking drive blade angle could fall below a minimum blade angle, which indicates overloading of the rotor blades and / or a stall on the rotor blades.

Accordingly, in one embodiment, the blade angles are adjusted in addition to the blade angle adjustment to support a wind tracking movement by the tracking drive by a lead angle dependent on the amplitude of this blade angle adjustment, this adjustment by the lead angle preferably taking place in the direction of the flag position of the rotor blades, in which the conversion of wind energy in mechanical or electrical performance becomes or is minimal.

In one embodiment, the blade angles are adjusted collectively by the (common) lead angle. Additionally or alternatively, the lead angle is at least 0.5 ° and / or at most 5 °.

As a result, in one embodiment, a stable (re) operating behavior and / or a particularly advantageous conversion of wind energy into mechanical or electrical power can be realized by the wind energy installation.

• - Ermitteln eines Windnachführbedarfs, in einer Ausführung mittels Ermitteln, insbesondere messtechnisches Erfassen, einer Abweichung zwischen einer, insbesondere aktuellen oder gemittelten, Windrichtung und der Rotorachsrichtung, insbesondere deren horizontaler Komponente;
• - Ermitteln der Amplitude der Blattwinkelverstellung zur Unterstützung der Windnachführbewegung durch den Nachführantrieb, in einer Ausführung auf Basis einer insbesondere empirisch und/oder mithilfe einer Simulation, vorgegebenen, insbesondere abgespeicherten und/oder einstellbaren, Abbildung von Windnachführbedarfswerten auf Blattwinkelverstellungsamplitudenwerte, insbesondere mithilfe eines Kennfeldes oder dergleichen; und
• - Einstellen der individuellen Blattwinkel der Rotorblätter auf Basis dieser Amplitude,

wobei diese Amplitude in Abhängigkeit von einem Rotordrehmoment um die Rotorachse und/oder einer Windnachführungsrichtung des Rotors um die Gierachse ermittelt wird und/oder die Blattwinkel in Abhängigkeit von einem ermittelten Vorhaltewinkel zur Einhaltung eines minimalen Blattwinkels eingestellt werden.In one embodiment, the method has the following steps:

• - Determining a wind tracking requirement, in one embodiment by means of determining, in particular measuring, a deviation between a, in particular current or averaged, wind direction and the rotor axis direction, in particular its horizontal component;
• - Determining the amplitude of the blade angle adjustment to support the wind tracking movement by the tracking drive, in an embodiment based on an, in particular empirically and / or with the aid of a simulation, predetermined, in particular stored and / or adjustable, mapping of wind tracking requirement values to blade angle adjustment amplitude values, in particular with the aid of a map or the like ; and
• Setting the individual blade angles of the rotor blades on the basis of this amplitude,

wherein this amplitude is determined as a function of a rotor torque about the rotor axis and / or a wind tracking direction of the rotor about the yaw axis and / or the blade angles are set as a function of a determined lead angle to maintain a minimum blade angle.

• - Ermitteln des Rotordrehmoments;
• - Ermitteln der Windnachführungsrichtung; und/oder
• - Ermitteln des Vorhaltewinkels.

The method accordingly has at least one of the steps:

• - determining the rotor torque;
• - determining the wind tracking direction; and or
• - Determine the lead angle.

• - Mittel zum Verstellen von Blattwinkeln der Rotorblätter um ihre Blattachse zur Unterstützung einer Windnachführbewegung durch den Nachführantrieb in einem Nachführbetriebsmodus

sowie wenigstens eines von:

• - Mittel zum Verstellen einer Amplitude dieser Blattwinkelverstellung in Abhängigkeit von einem Rotordrehmoment um die Rotorachse und/oder einer Windnachführungsrichtung des Rotors um die Gierachse; und/oder
• - Mittel zum Verstellen der Blattwinkel zusätzlich (zu der Blattwinkelverstellung zur Unterstützung einer Windnachführbewegung durch den Nachführantrieb) um einen Vorhaltewinkel in Abhängigkeit von einer Amplitude dieser Blattwinkelverstellung (zur Unterstützung einer Windnachführbewegung durch den Nachführantrieb)zur Einhaltung eines minimalen Blattwinkels.

As already mentioned, according to one embodiment of the present invention, a system for operating the wind energy installation, in particular hardware and / or software, in particular program technology, is set up to carry out a method described here. Accordingly, according to an embodiment of the present invention, it has:

• - Means for adjusting blade angles of the rotor blades about their blade axis to support a wind tracking movement by the tracking drive in a tracking operating mode

as well as at least one of:

• - Means for adjusting an amplitude of this blade angle adjustment as a function of a rotor torque about the rotor axis and / or a wind tracking direction of the rotor about the yaw axis; and or
• - Means for adjusting the blade angle in addition (to the blade angle adjustment to support a wind tracking movement by the tracking drive) by a lead angle depending on an amplitude of this blade angle adjustment (to support a wind tracking movement by the tracking drive) to maintain a minimum blade angle.

According to an embodiment of the present invention, the blade angles of the rotor blades are adjusted about their (respective) blade axis to support a wind tracking movement by the tracking drive for or when operating the wind energy installation in the tracking operating mode, the tracking drive for wind tracking the rotor about the yaw axis by a predetermined, In one embodiment, an adjustable, in particular constant, or variable waiting time after the blade angle adjustment of the rotor blades about their blade axis is activated to support this wind tracking movement.

In one embodiment, the blade angle adjustment of the rotor blades is thus first activated to support the wind tracking movement, and after the waiting time the tracking drive is then used to carry out the wind tracking movement induced by it.

If, in a preferred embodiment, the wind power installation has at least one parking brake, this parking brake is first released in an embodiment after a predetermined, in particular constant, or variable (first) waiting time after activation of the blade angle adjustment, and after a predetermined, in one Execution adjustable, in particular constant, or variable further (second) waiting time after releasing the parking brake, the tracking drive is activated, so that the tracking drive is activated by a waiting time after the blade angle adjustment to support the wind tracking movement, which is the sum of these two waiting times.

This is based in particular on the idea that particularly high loads can act on the drive at the beginning of a tracking operating mode, for example due to inertia, static friction or the like. By activating the blade angle adjustment in advance to support a wind tracking movement by the tracking drive, high initial loads can advantageously be at least partially absorbed or compensated for in one embodiment by the blade angle adjustment. Additionally or alternatively, in such an embodiment, such a forward movement of the blade angle adjustment to support a wind tracking movement by the tracking drive can advantageously already have a corresponding supporting, aerodynamically induced torque.

In this way, loads of the tracking drive can be reduced in one embodiment, in particular larger wind power plants or constant wind power plants with smaller tracking drives (slast) can therefore be operated with constant tracking drives.

In one embodiment, the waiting time is specified as a function of a rotor rotational frequency, a wind speed and / or a rotor torque about the rotor axis.

The specification as a function of a rotor rotational frequency is based in particular on the idea that, at higher rotor rotational frequencies, a corresponding, in particular sufficient, supporting torque can be built up more quickly about the yaw axis through the blade angle adjustment to support a wind tracking movement by the tracking drive. Accordingly, in one embodiment, the tracking drive for wind tracking the rotor around the yaw axis is activated by a first waiting time after the blade angle adjustment of the rotor blades about their blade axis to support this wind tracking movement, and in the case of a higher second rotor rotating frequency by a shorter second waiting time after the blade angle adjustment.

Analogously, the specification as a function of a wind speed is based in particular on the idea that, at higher wind speeds, the blade angle adjustment to support a wind tracking movement by the tracking drive enables a corresponding, in particular sufficient, supporting torque to be built up around the yaw axis more quickly. Correspondingly, in a version with a first Wind speeds of the tracking drive for wind tracking of the rotor around the yaw axis are activated for a first waiting time after the blade angle adjustment of the rotor blades about their blade axis to support this wind tracking movement and, at a higher second wind speeds, for a shorter second waiting time after the blade angle adjustment.

The specification as a function of a rotor torque is based in particular on the idea already explained that a torque about the rotor axis can be a particularly suitable indicator for the (setting of) the waiting time, since it reflects the load or load condition of the wind energy installation particularly well. For example, higher wind loads generally lead to larger rotor torques and, at the same time, require stronger support of a wind tracking movement induced by the tracking drive through the blade angle adjustment. Additionally or alternatively, in one embodiment, a rotor torque that is already present or is known in any case, in particular for controlling the wind energy installation, can also be used to determine the waiting time. Accordingly, in one embodiment, the tracking drive for wind tracking the rotor about the yaw axis is activated for a first waiting time after the blade angle adjustment of the rotor blades about their blade axis to support this wind tracking movement, and for a higher second rotor torque by a longer second waiting time after the blade angle adjustment.

As a result, in each case, in particular in combination of two or three of the above-mentioned influencing variables rotor rotational frequency, wind speed and rotor torque, a short waiting time can advantageously be adapted to the situation, and the wind tracking as a whole can thereby be accelerated.

In one embodiment, the tracking drive for wind tracking of the rotor about the yaw axis is deactivated together, or, at least essentially, simultaneously with the blade angle adjustment of the rotor blades about their blade axis in order to support this wind tracking movement.

This is based in particular on the idea that at the end of a tracking operating mode, small (re) loads can act on the drive. By deactivating the blade angle adjustment to support a wind tracking movement together with the tracking drive, a deterioration in the conversion of wind energy into mechanical or electrical power as a result of this blade angle adjustment can be ended more quickly, and thus the conversion of wind energy into mechanical or electrical power by the wind power installation be improved.

In another embodiment, the tracking drive for wind tracking of the rotor about the yaw axis is deactivated by a predetermined lead time before the blade angle adjustment of the rotor blades about their blade axis to support this wind tracking movement.

In this way, loads of the tracking drive can be further reduced in one embodiment, in particular, therefore, larger wind turbines or constant wind turbines with smaller tracking drives (slast) can be operated with constant tracking drives.

In one embodiment, the waiting time between the activation of the blade angle adjustment and the activation of the tracking drive is at least 0.25 seconds or 250 ms, in particular at least 0.5 seconds or 500 ms, and / or at most 30 seconds, in particular at most 5 seconds, in one execution at most 2.5 seconds.

In this way, the duration of the wind tracking and the load on the tracking drive can be minimized in one embodiment.

According to an embodiment of the present invention, the blade angles of the rotor blades are adjusted about their (respective) blade axis to support a wind tracking movement by the tracking drive for or during operation of the wind power plant in the tracking operating mode, with a commanded phase shift of an amplitude of this blade angle adjustment relative to a rotor-fixed reference angle position by Rotor axis is dynamically adjusted depending on a rotor rotational frequency of the rotor around the rotor axis. In one embodiment, the rotor-fixed reference angle position is determined on the basis of a determined (in particular metrologically recorded) rotor (rotational) position.

In particular due to mechanical, hydraulic, electrical, in particular electromotive or magnetic and / or signal inertia, a commanded amplitude of the blade angle adjustment is only realized with a certain delay. In addition, the transient aerodynamics cause a delay in the build-up of the supporting torque induced by the blade angle adjustment around the yaw axis. As a result, the support of a wind tracking movement induced by the tracking drive is impaired by the blade angle adjustment.

These delays can be at least partially compensated for by a phase shift in the commanded amplitude of the blade angle adjustment compared to a rotor-fixed reference angle position, and the support can thus be improved.

If, as already explained above, the individual (amplitudes of) the blade angle adjustment (s) of the individual rotor blades are mutually phase-shifted about the rotor axis, then in one embodiment, all (amplitudes of) the blade angle adjustment (s) of the individual rotor blades are additionally adjusted by the same value compared to one rotor-fixed reference angle position out of phase about the rotor axis, which thus represents a commanded phase shift of an amplitude of the blade angle adjustment to support a wind tracking movement by the tracking drive in the sense of the present invention. A commanded phase shift in the sense of the present invention is, in one embodiment, a phase shift which, in particular currently, is output by a controller and / or as a target value or a, in particular current, target value.

The dynamic adjustment of the commanded phase shift as a function of a rotor rotational frequency is based in particular on the idea that, at higher rotor rotational frequencies, the commanded phase shift, as it were, has to be kept stronger in order to be able to provide support for a wind tracking movement by the tracking drive in an aerodynamically timely manner and at a sufficient level.

Correspondingly, in one embodiment, the commanded phase shift has a first phase shift value for a first value of the rotor rotational frequency and a second phase shift value which is larger, in particular in terms of amount, for a larger second value of the rotor rotational frequency.

In addition to a component that is dependent on the rotor rotational frequency or dynamic, the commanded phase shift in one embodiment can also have a component that is independent or static of the rotor rotational frequency.

As a result, mechanical, hydraulic, electrical, in particular electromotive or magnetic and / or signal-related inertia can advantageously be at least partially compensated for in one embodiment.

• - Ermitteln eines Windnachführbedarfs, in einer Ausführung mittels Ermitteln, insbesondere messtechnisches Erfassen, einer Abweichung zwischen einer, insbesondere aktuellen oder gemittelten, Windrichtung und der Rotorachsrichtung, insbesondere deren horizontaler Komponente;
• - Ermitteln der Amplitude der Blattwinkelverstellung zur Unterstützung der Windnachführbewegung durch den Nachführantrieb, in einer Ausführung auf Basis einer insbesondere empirisch und/oder mithilfe einer Simulation, vorgegebenen, insbesondere abgespeicherten und/oder einstellbaren, Abbildung von Windnachführbedarfswerten auf Blattwinkelverstellungsamplitudenwerte, insbesondere mithilfe eines Kennfeldes oder dergleichen; und
• - Einstellen der individuellen Blattwinkel der Rotorblätter auf Basis dieser Amplitude, sowie die Schritte:
• - Ermitteln einer Rotordrehfrequenz;
• - Ermitteln einer Phasenverschiebung der Amplitude in Abhängigkeit von der Rotordrehfrequenz; und
• - Einstellen der individuellen Blattwinkel der Rotorblätter auf Basis dieser Phasenverschiebung;

und/oder den Schritt:

• - Aktivieren des Nachführantriebs zum Windnachführen des Rotors um die Gierachse um eine vorgegebene Wartezeit nach Aktivieren der Blattwinkelverstellung der Rotorblätter um ihre Blattachse zur Unterstützung dieser Windnachführbewegung

auf. In einer Ausführung wird eine Rotor(dreh)position ermittelt, insbesondere messtechnisch erfasst, und eine rotorfeste Referenzwinkellage, auf die die Phasenverschiebung bezogen ist, auf Basis dieser Rotor(dreh)position ermittelt.In one embodiment, the method has the following steps:

• - Determining a wind tracking requirement, in one embodiment by means of determining, in particular measuring, a deviation between a, in particular current or averaged, wind direction and the rotor axis direction, in particular its horizontal component;
• - Determining the amplitude of the blade angle adjustment to support the wind tracking movement by the tracking drive, in an embodiment based on an, in particular empirically and / or with the aid of a simulation, predetermined, in particular stored and / or adjustable, mapping of wind tracking requirement values to blade angle adjustment amplitude values, in particular with the aid of a map or the like ; and
• - Setting the individual blade angles of the rotor blades based on this amplitude, as well as the steps:
• - determining a rotor rotational frequency;
• - Determining a phase shift of the amplitude as a function of the rotor rotational frequency; and
• - Setting the individual blade angle of the rotor blades based on this phase shift;

and / or the step:

• - Activation of the tracking drive for wind tracking of the rotor about the yaw axis by a predetermined waiting time after activation of the blade angle adjustment of the rotor blades about their blade axis to support this wind tracking movement

on. In one embodiment, a rotor (rotary) position is determined, in particular measured, and a rotor-fixed reference angle position, to which the phase shift is based, is determined on the basis of this rotor (rotary) position.

A means in the sense of the present invention can be designed in terms of hardware and / or software, in particular a data, or signal, preferably digital, processing, in particular microprocessor unit (CPU), graphics card (GPU) that is data or signal connected to a memory and / or bus system ) or the like, and / or have one or more programs or program modules. The processing unit can be designed to process commands that are implemented as a program stored in a memory system, to acquire input signals from a data bus and / or to output signals to a data bus. A storage system can have one or more, in particular different, storage media, in particular optical, magnetic, solid-state and / or other non-volatile media. The program can be designed in such a way that it embodies or is capable of executing the methods described here, so that the processing unit can carry out the steps of such methods and thus in particular can operate the wind energy installation. A computer program product can, in one embodiment, have, in particular non-volatile, storage medium for storing a program or with a program stored thereon, execution of this program prompting a system or a control, in particular a computer, to implement a method or one or more described here to carry out his steps.

In one embodiment, one or more, in particular all, steps of the method are carried out completely or partially automatically, in particular by the system or its means.

In one embodiment, the system has the wind turbine.

• einen um eine Rotorachse drehbaren Rotor mit wenigstens zwei individuell um ihre Blattachse verstellbaren Rotorblättern und
• einen Nachführantrieb zum Windnachführen des Rotors um eine Gierachse aufweist, wobei in einem Nachführbetriebsmodus Blattwinkel der Rotorblätter um ihre Blattachse zur Unterstützung einer Windnachführbewegung durch den Nachführantrieb verstellt werden,
• wobei eine Amplitude dieser Blattwinkelverstellung
  • - um oder auf einen vorgegebenen Wert reduziert wird, falls eine Giergeschwindigkeit des Rotors um die Gierachse in einem vorgegebenen Reduzier-Geschwindigkeitsbereich liegt, der eine untere Reduzier-Geschwindigkeitsgrenze aufweist; und/oder
  • - um oder auf einen vorgegebenen Wert erhöht wird, falls eine Giergeschwindigkeit des Rotors um die Gierachse in einem vorgegebenen Erhöhungs-Geschwindigkeitsbereich liegt, der eine obere Erhöhungs-Geschwindigkeitsgrenze aufweist.

A first aspect of the present invention relates to a method for operating a wind power plant, the

• a rotor which can be rotated about a rotor axis and has at least two rotor blades which can be adjusted individually about their blade axis and
• has a tracking drive for wind tracking of the rotor about a yaw axis, with blade angles of the rotor blades being adjusted about their blade axis in a tracking operating mode to support a wind tracking movement by the tracking drive,
• with an amplitude of this blade angle adjustment
  • is reduced by or to a predetermined value if a yaw rate of the rotor about the yaw axis lies in a predetermined reduction speed range which has a lower reduction speed limit; and or
  • - Increased by or to a predetermined value if a yaw rate of the rotor about the yaw axis lies in a predetermined increase speed range which has an upper increase speed limit.

• - um oder auf einen vorgegebenen Wert reduziert wird, falls die Giergeschwindigkeit in einem vorgegebenen zweiten Reduzier-Geschwindigkeitsbereich liegt, der eine zweite untere Reduzier-Geschwindigkeitsgrenze aufweist; und/oder
• - um oder auf einen vorgegebenen Wert erhöht wird, falls die Giergeschwindigkeit in einem vorgegebenen zweiten Erhöhungs-Geschwindigkeitsbereich liegt, der eine zweite obere Erhöhungs-Geschwindigkeitsgrenze liegt.

In a development of this first aspect, the method is characterized in that, in the tracking operating mode, the amplitude of the blade angle adjustment to support a wind tracking movement by the tracking drive

• is reduced by or to a predetermined value if the yaw rate is in a predetermined second reduction speed range which has a second lower reduction speed limit; and or
• - Is increased by or to a predetermined value if the yaw rate is in a predetermined second increase speed range, which is a second upper increase speed limit.

• - wenigstens ein, insbesondere wenigstens zwei, und/oder höchstens vier Reduzier-Geschwindigkeitsbereiche, insbesondere genau ein oder zwei Reduzier-Geschwindigkeitsbereiche, vorgesehen sind, für die die Amplitude der Blattwinkelverstellung jeweils geschwindigkeitsbereichspezifisch reduziert wird; und/oder
• - wenigstens ein, insbesondere wenigstens zwei, und/oder höchstens vier Erhöhungs-Geschwindigkeitsbereiche, insbesondere genau ein oder zwei Erhöhungs-Geschwindigkeitsbereiche, vorgesehen sind, für die die Amplitude der Blattwinkelverstellung jeweils geschwindigkeitsbereichspezifisch erhöht wird.

Additionally or alternatively, the method in a development of this first aspect is characterized in that in the follow-up operating mode

• - At least one, in particular at least two, and / or at most four reduction speed ranges, in particular exactly one or two reduction speed ranges, are provided, for which the amplitude of the blade angle adjustment is reduced in each case in a speed range-specific manner; and or
• - At least one, in particular at least two, and / or at most four increase speed ranges, in particular exactly one or two increase speed ranges, are provided, for which the amplitude of the blade angle adjustment is increased in each case specific to the speed range.

In a development of the first aspect, in particular one of its developments mentioned above, the method is characterized in that a speed range extends over at least 0.05 ° per second.

• - Ermitteln eines Windnachführbedarfs;
• - Ermitteln der Amplitude der Blattwinkelverstellung zur Unterstützung der Windnachführbewegung durch den Nachführantrieb;
• - Einstellen der individuellen Blattwinkel der Rotorblätter auf Basis dieser Amplitude
• - Ermitteln eines Ist-Wertes der Giergeschwindigkeit des Rotors um die Gierachse;
• - stufenförmiges Reduzieren der ermittelten Amplitude, falls der Ist-Wert einen oder mehrere vorgegebene Geschwindigkeitsgrenzen überschreitet; und/oder stufenförmiges Erhöhen der ermittelten Amplitude, falls der Ist-Wert einen oder mehrere vorgegebene Geschwindigkeitsgrenzen unterschreitet; sowie
• - Einstellen der individuellen Blattwinkel der Rotorblätter auf Basis dieser Amplitude.

In a further development of the first aspect, in particular one of its further developments mentioned above, the method is characterized by the steps:

• - determining a wind tracking requirement;
• - Determining the amplitude of the blade angle adjustment to support the wind tracking movement by the tracking drive;
• - Setting the individual blade angles of the rotor blades based on this amplitude
• Determining an actual value of the yaw rate of the rotor about the yaw axis;
• - stepwise reduction of the determined amplitude if the actual value exceeds one or more predetermined speed limits; and / or incrementally increasing the determined amplitude if the actual value falls below one or more predetermined speed limits; such as
• - Setting the individual blade angles of the rotor blades based on this amplitude.

• - Mittel zum Verstellen von Blattwinkeln der Rotorblätter um ihre Blattachse zur Unterstützung einer Windnachführbewegung durch den Nachführantrieb in einem Nachführbetriebsmodus sowie
• - Mittel zum Reduzieren einer Amplitude dieser Blattwinkelverstellung um oder auf einen vorgegebenen Wert, falls eine Giergeschwindigkeit des Rotors um die Gierachse in einem vorgegebenen Reduzier-Geschwindigkeitsbereich liegt, der einer untere Reduzier-Geschwindigkeitsgrenze aufweist; und/oder
• - Mittel zum Erhöhen einer Amplitude dieser Blattwinkelverstellung um oder auf einen vorgegebenen Wert, falls eine Giergeschwindigkeit des Rotors um die Gierachse in einem vorgegebenen Erhöhungs-Geschwindigkeitsbereich liegt, der eine obere Erhöhungs-Geschwindigkeitsgrenze aufweist.

The first aspect of the present invention also relates to a system for operating a wind energy installation which individually rotates a rotor which can be rotated about a rotor axis with at least two its blade axis has adjustable rotor blades and a tracking drive for wind tracking the rotor around a yaw axis, the system being set up and / or having a method according to the first aspect, in particular one of its developments mentioned above:

• - Means for adjusting blade angles of the rotor blades about their blade axis to support a wind tracking movement by the tracking drive in a tracking operating mode and
• Means for reducing an amplitude of this blade angle adjustment by or to a predetermined value if a yaw rate of the rotor around the yaw axis lies in a predetermined reduction speed range which has a lower reduction speed limit; and or
• - Means for increasing an amplitude of this blade angle adjustment by or to a predetermined value if a yaw rate of the rotor about the yaw axis lies in a predetermined increase speed range which has an upper increase speed limit.

The first aspect of the present invention also relates to a computer program product with a program code, which is stored on a medium readable by a computer, for carrying out a method according to the first aspect, in particular one of its developments mentioned above.

• einen um eine Rotorachse drehbaren Rotor mit wenigstens zwei individuell um ihre Blattachse verstellbaren Rotorblättern und
• einen Nachführantrieb zum Windnachführen des Rotors um eine Gierachse aufweist, wobei in einem Nachführbetriebsmodus Blattwinkel der Rotorblätter um ihre Blattachse zur Unterstützung einer Windnachführbewegung durch den Nachführantrieb verstellt werden,
• wobei eine Amplitude dieser Blattwinkelverstellung in Abhängigkeit von
  • - einem Rotordrehmoment um die Rotorachse und/oder
  • - einer Windnachführungsrichtung des Rotors um die Gierachse verstellt wird; und/oder wobei
  • - die Blattwinkel in Abhängigkeit von einer Amplitude dieser Blattwinkelverstellung zusätzlich um einen Vorhaltewinkel zur Einhaltung eines minimalen Blattwinkels verstellt werden.

A second aspect of the present invention, which can be combined in an embodiment with the above-mentioned first aspect, in particular one of its above-mentioned developments, relates to a method for operating a wind power plant, the

• a rotor which can be rotated about a rotor axis and has at least two rotor blades which can be adjusted individually about their blade axis and
• has a tracking drive for wind tracking of the rotor about a yaw axis, with blade angles of the rotor blades being adjusted about their blade axis in a tracking operating mode to support a wind tracking movement by the tracking drive,
• an amplitude of this blade angle adjustment depending on
  • - A rotor torque around the rotor axis and / or
  • - A wind tracking direction of the rotor is adjusted about the yaw axis; and / or where
  • - The blade angles are additionally adjusted by a lead angle to maintain a minimum blade angle depending on an amplitude of this blade angle adjustment.

In a development of this second aspect, the method is characterized in that the amplitude of the blade angle adjustment to support a wind tracking movement by the tracking drive is zero if the rotor torque falls below a predetermined torque limit.

Additionally or alternatively, in a further development of this second aspect, the method is characterized in that the rotor torque is determined on the basis of a torque setpoint.

In a further development of the second aspect, in particular one of its above-mentioned further developments, the method is characterized in that the amplitude of the blade angle adjustment to support a wind tracking movement by the tracking drive in a first wind tracking direction and the amplitude of the blade angle adjustment to support a wind tracking movement by the tracking drive in a for this purpose, the second wind tracking direction in the opposite direction has an offset, in particular a predetermined and / or constant or dependent on a rotor torque.

In a development of the second aspect, in particular one of its developments mentioned above, the method is characterized in that the blade angles are adjusted collectively by the lead angle.

• - Ermitteln eines Windnachführbedarfs;
• - Ermitteln der Amplitude der Blattwinkelverstellung zur Unterstützung der Windnachführbewegung durch den Nachführantrieb; und
• - Einstellen der individuellen Blattwinkel der Rotorblätter auf Basis dieser Amplitude,

wobei diese Amplitude in Abhängigkeit von einem Rotordrehmoment um die Rotorachse und/oder einer Windnachführungsrichtung des Rotors um die Gierachse ermittelt wird und/oder die Blattwinkel in Abhängigkeit von einem ermittelten Vorhaltewinkel zur Einhaltung eines minimalen Blattwinkels eingestellt werden.In a further development of the second aspect, in particular one of its further developments mentioned above, the method is characterized by the steps:

• - determining a wind tracking requirement;
• - Determining the amplitude of the blade angle adjustment to support the wind tracking movement by the tracking drive; and
• Setting the individual blade angles of the rotor blades on the basis of this amplitude,

wherein this amplitude is determined as a function of a rotor torque about the rotor axis and / or a wind tracking direction of the rotor about the yaw axis and / or the blade angles are set as a function of a determined lead angle to maintain a minimum blade angle.

• wobei das System zur Durchführung eines Verfahrens nach dem zweiten Aspekt, insbesondere einer seiner oben genannten Weiterbildungen, eingerichtet ist und/oder aufweist:
  • - Mittel zum Verstellen von Blattwinkeln der Rotorblätter um ihre Blattachse zur Unterstützung einer Windnachführbewegung durch den Nachführantrieb in einem Nachführbetriebsmodus sowie
  • - Mittel zum Verstellen einer Amplitude dieser Blattwinkelverstellung in Abhängigkeit von einem Rotordrehmoment um die Rotorachse und/oder einer Windnachführungsrichtung des Rotors um die Gierachse; und/oder
  • - Mittel zum Verstellen der Blattwinkel zur Einhaltung eines minimalen Blattwinkels zusätzlich um einen Vorhaltewinkel in Abhängigkeit von einer Amplitude dieser Blattwinkelverstellung .

The second aspect of the present invention also relates to a system for operating a wind energy installation which has a rotor which can be rotated about a rotor axis with at least two rotor blades which can be individually adjusted about its blade axis and a tracking drive for wind tracking of the rotor about a yaw axis,

• wherein the system is set up and / or has a method for carrying out a method according to the second aspect, in particular one of its above-mentioned further developments:
  • - Means for adjusting blade angles of the rotor blades about their blade axis to support a wind tracking movement by the tracking drive in a tracking operating mode and
  • - Means for adjusting an amplitude of this blade angle adjustment as a function of a rotor torque about the rotor axis and / or a wind tracking direction of the rotor about the yaw axis; and or
  • - Means for adjusting the blade angle to maintain a minimum blade angle additionally by a lead angle depending on an amplitude of this blade angle adjustment.

The second aspect of the present invention also relates to a computer program product with a program code, which is stored on a medium readable by a computer, for carrying out a method according to the second aspect, in particular one of its developments mentioned above.

• einen um eine Rotorachse drehbaren Rotor mit wenigstens zwei individuell um ihre Blattachse verstellbaren Rotorblättern und
• einen Nachführantrieb zum Windnachführen des Rotors um eine Gierachse aufweist, wobei in einem Nachführbetriebsmodus Blattwinkel der Rotorblätter um ihre Blattachse zur Unterstützung einer Windnachführbewegung durch den Nachführantrieb verstellt werden, wobei
  • - der Nachführantrieb zum Windnachführen des Rotors um die Gierachse um eine vorgegebene Wartezeit nach der Blattwinkelverstellung der Rotorblätter um ihre Blattachse zur Unterstützung dieser Windnachführbewegung aktiviert wird; und/oder
  • - eine kommandierte Phasenverschiebung einer Amplitude dieser Blattwinkelverstellung gegenüber einer rotorfesten Referenzwinkellage um die Rotorachse in Abhängigkeit von einer Rotordrehfrequenz des Rotors um die Rotorachse dynamisch verstellt wird.

A third aspect of the present invention, which can be combined in an embodiment with the above-mentioned first and / or second aspect, in particular one of its / its above-mentioned further developments, relates to a method for operating a wind energy plant, the

• a rotor which can be rotated about a rotor axis and has at least two rotor blades which can be adjusted individually about their blade axis and
• has a tracking drive for wind tracking of the rotor about a yaw axis, with blade angles of the rotor blades being adjusted about their blade axis to support a wind tracking movement by the tracking drive in a tracking operating mode, wherein
  • - The tracking drive for wind tracking of the rotor about the yaw axis is activated by a predetermined waiting time after the blade angle adjustment of the rotor blades about their blade axis to support this wind tracking movement; and or
  • - A commanded phase shift of an amplitude of this blade angle adjustment relative to a rotor-fixed reference angular position about the rotor axis is dynamically adjusted depending on a rotor rotational frequency of the rotor about the rotor axis.

In a development of this third aspect, the method is characterized in that the waiting time is predefined as a function of a rotor rotational frequency, a wind speed and / or a rotor torque about the rotor axis.

Additionally or alternatively, in a further development of this third aspect, the method is characterized in that the tracking drive for wind tracking of the rotor about the yaw axis is deactivated together with the blade angle adjustment of the rotor blades about their blade axis to support this wind tracking movement or by a predetermined lead time before this blade angle adjustment.

In a development of the third aspect, in particular one of its developments mentioned above, the method is characterized in that the waiting time is at least 0.25 seconds and / or at most 30 seconds.

In a development of the third aspect, in particular one of its developments mentioned above, the method is characterized in that the commanded phase shift additionally has a static component that is independent of the rotor rotational frequency.

In a development of the third aspect, in particular one of its developments mentioned above, the method is characterized in that the commanded phase shift has a first phase shift value for a first value of the rotor rotational frequency and a larger second phase shift value for a larger second value of the rotor rotational frequency.

• - Ermitteln eines Windnachführbedarfs;
• - Ermitteln der Amplitude der Blattwinkelverstellung zur Unterstützung der Windnachführbewegung durch den Nachführantrieb; und
• - Einstellen der individuellen Blattwinkel der Rotorblätter auf Basis dieser Amplitude,

wobei das Verfahren die Schritte:

• - Ermitteln einer Rotordrehfrequenz;
• - Ermitteln einer Phasenverschiebung der Amplitude in Abhängigkeit von der Rotordrehfrequenz; und
• - Einstellen der individuellen Blattwinkel der Rotorblätter auf Basis dieser Phasenverschiebung;

und/oder den Schritt:

• - Aktivieren des Nachführantriebs zum Windnachführen des Rotors um die Gierachse um eine vorgegebene Wartezeit nach Aktivieren der Blattwinkelverstellung der Rotorblätter um ihre Blattachse zur Unterstützung dieser Windnachführbewegung

aufweist.In a further development of the third aspect, in particular one of its further developments mentioned above, the method has the steps:

• - determining a wind tracking requirement;
• - Determining the amplitude of the blade angle adjustment to support the wind tracking movement by the tracking drive; and
• Setting the individual blade angles of the rotor blades on the basis of this amplitude,

the process following the steps:

• - Determining a rotor rotational frequency;
• - Determining a phase shift of the amplitude as a function of the rotor rotational frequency; and
• - Setting the individual blade angle of the rotor blades based on this phase shift;

and / or the step:

• - Activation of the tracking drive for wind tracking of the rotor about the yaw axis by a predetermined waiting time after activation of the blade angle adjustment of the rotor blades about their blade axis to support this wind tracking movement

having.

• wobei das System zur Durchführung eines Verfahrens nach dem dritten Aspekt, insbesondere einer seiner oben genannten Weiterbildungen, eingerichtet ist und/oder aufweist:
  • - Mittel zum Verstellen von Blattwinkeln der Rotorblätter um ihre Blattachse zur Unterstützung einer Windnachführbewegung durch den Nachführantrieb in einem Nachführbetriebsmodus sowie
  • - Mittel zum Aktivieren des Nachführantriebs zum Windnachführen des Rotors um die Gierachse um eine vorgegebene Wartezeit nach der Blattwinkelverstellung der Rotorblätter um ihre Blattachse zur Unterstützung dieser Windnachführbewegung wird; und/oder
  • - Mittel zum dynamischen Verstellen einer kommandierten Phasenverschiebung einer Amplitude dieser Blattwinkelverstellung gegenüber einer rotorfesten Referenzwinkellage um die Rotorachse in Abhängigkeit von einer Rotordrehfrequenz des Rotors um die Rotorachse.

The third aspect of the present invention also relates to a system for operating a wind energy installation which has a rotor which can be rotated about a rotor axis with at least two rotor blades which can be individually adjusted about its blade axis and a tracking drive for wind tracking of the rotor about a yaw axis,

• the system for carrying out a method according to the third aspect, in particular one of its above-mentioned developments, is set up and / or has:
  • - Means for adjusting blade angles of the rotor blades about their blade axis to support a wind tracking movement by the tracking drive in a tracking operating mode and
  • - Means for activating the tracking drive for wind tracking of the rotor about the yaw axis by a predetermined waiting time after the blade angle adjustment of the rotor blades about their blade axis to support this wind tracking movement; and or
  • - Means for dynamically adjusting a commanded phase shift of an amplitude of this blade angle adjustment with respect to a rotor-fixed reference angle position about the rotor axis as a function of a rotor rotational frequency of the rotor about the rotor axis.

The third aspect of the present invention also relates to a computer program product with a program code, which is stored on a medium readable by a computer, for carrying out a method according to the third aspect, in particular one of its developments mentioned above.

• 1: ein System zum Betreiben einer Windenergieanlage nach einer Ausführung der vorliegenden Erfindung;
• 2: ein Verfahren zum Betreiben der Windenergieanlage nach einer Ausführung der vorliegenden Erfindung;
• 3: ein Verfahren zum Betreiben der Windenergieanlage nach einer weiteren Ausführung der vorliegenden Erfindung; und
• 4: ein Verfahren zum Betreiben der Windenergieanlage nach einer weiteren Ausführung der vorliegenden Erfindung.

Further advantages and features result from the subclaims and the exemplary embodiments. Here shows, partly schematically:

• 1 : a system for operating a wind turbine according to an embodiment of the present invention;
• 2nd : a method for operating the wind turbine according to an embodiment of the present invention;
• 3rd : a method for operating the wind power plant according to a further embodiment of the present invention; and
• 4th : A method for operating the wind turbine according to a further embodiment of the present invention.

1 shows a system for operating a wind turbine according to an embodiment of the present invention.

The wind turbine has a tower 110 on which a gondola 120 about an at least substantially vertical yaw axis G is rotatably mounted.

At the gondola 120 is a rotor 130 about a rotor axis R rotatably supported by a generator or a gear generator unit 140 has or is coupled thereto to electrical energy in a power grid 150 feed.

In the exemplary embodiment, the rotor has three individually about its (respective) blade axis B adjustable rotor blades 30th on. A controller controls this 100 corresponding blade adjustment device (not shown).

The wind turbine has a tracking drive 20th with one or more electric motor (s) and / or gear (s) for twisting or tracking the nacelle depending on the wind direction 120 and thus the rotor 130 around the yaw axis G on, also from the controller 100 is controlled.

The control 100 executes a method of operating the wind turbine according to an embodiment of the present invention.

In an execution that in 2nd the controller determines 100 in a first step S10 using a wind vane 10th a deviation between a wind direction and the horizontal component of the (into the nacelle 120 oriented) rotor axis.

If this deviation exceeds a predetermined minimum value ( S20 : " Y “), Determines the control 100 that there is a need for wind tracking and switches to a tracking operating mode, otherwise ( S20 : " N “) Returns the procedure or control to step S10 back.

In the follow-up operating mode, it determines in one step S30 an amplitude of a cyclic blade angle adjustment of the rotor blades 30th to support a wind tracking movement by the tracking drive around the nacelle 120 and with it the rotor 130 around the yaw axis G to be twisted in such a way that the deviation is reduced ("wind tracking movement by the tracking drive"). This amplitude can be, for example, a stored, constant or read reference value from a map.

In one step S40 it adjusts the blade angle of the rotor blades 30th according to this amplitude and also controls the tracking drive 20th so that he's the gondola 120 and with it the rotor 130 around the yaw axis G twisted in such a way that the deviation is reduced.

It also determines in step S40 an actual value of the yaw rate of the nacelle and thus of the rotor around the yaw axis.

If this value exceeds a predefined (first) lower reduction speed limit ( S50 : " Y “), Is in one step S55 the in step S30 determined amplitude is reduced to or by a predetermined value and the method or the controller moves with step S60 away.

Otherwise ( S50 : " N “) The process or control moves directly to step S60 continued, ie without reducing the in step S30 determined amplitude.

In step S60 controls the control 100 the blade adjustment device such that the individual blade angle of the rotor blades 30th cyclically in step with this S30 determined and if necessary in step S55 reduced amplitude and so that in step S60 continued wind tracking movement by the tracking drive 20th continue to support.

Then the method or the control returns to step S10 back.

In another version, which in 3rd the controller determines 100 in a first step S110 using the wind vane 10th a deviation between a wind direction and the horizontal component of the (into the nacelle 120 oriented) rotor axis.

If this deviation exceeds a predetermined minimum value ( S120 : " Y “), Determines the control 100 that there is a need for wind tracking and switches to a tracking operating mode, otherwise ( S120 : " N “) Returns the procedure or control to step S110 back.

In follow-up mode, it determines in step S130 a target value for a rotor torque, for example on the basis of a power requirement for the wind turbine or the like, a wind tracking direction of the rotor about the yaw axis (by “ CW "(" ClockWise ")," CCW "(" CounterClockWise ") in 1 indicated) and an amplitude of a blade angle adjustment to support a wind tracking movement by the tracking drive. This amplitude can be, for example, a stored, constant or read reference value from a map.

Are the wind tracking direction and the direction in which the rotor 130 due to the tilt angle without blade angle adjustment to support a wind tracking movement by the tracking drive the gondola 120 tries to turn, in opposite directions ( S140 : " Y “), This amplitude is in one step S145 a constant offset is added and the controller or method moves to step S150 away. This is done in the case of the usually customary right-hand rotors with the wind looking at the rotor from the front when there is a need for tracking in the CCW direction or counterclockwise. Otherwise ( S140 : " N “) The control or the process moves directly to step S150 away. Conversely, in a modification, the step S130 determined amplitude in one step S145 be reduced by a constant offset if the wind tracking direction and the direction in which the rotor 130 the gondola without blade angle adjustment to support a wind tracking movement by the tracking drive 120 tries to turn, are in the same or not in opposite directions. In an advantageous alternative embodiment, the offset is not constant but proportional to that in step S130 determined target value for the rotor torque.

If the rotor torque or the (rotor) torque setpoint falls below a predetermined torque limit value ( S150 : " Y “) Sets the control in one step S155 the amplitude of the blade angle adjustment to support a wind tracking movement by the tracking drive to zero and moves with step S160 continued, otherwise ( S150 : " N “) The control or the process moves directly to step S160 away.

In step S160 the controller determines 100 depending on the step in S130 , S145 respectively. 155 determined amplitude of the blade angle adjustment a lead angle to maintain a minimum blade angle and adjusts the blade angle cyclically with the amplitude and additionally collectively by this lead angle. It also controls the tracking drive 20th so that he's the gondola 120 and with it the rotor 130 around the yaw axis G twisted in such a way that the deviation is reduced.

In another version, which in 4th the controller determines 100 in a first step S210 using the wind vane 10th a deviation between a wind direction and the horizontal component of the (into the nacelle 120 oriented) rotor axis.

If this deviation exceeds a predetermined minimum value ( S220 : " Y “), Determines the control 100 that there is a need for wind tracking and switches to a tracking operating mode, otherwise ( S220 : " N “) Returns the procedure or control to step S210 back.

In the follow-up operating mode, it determines in one step S230 a rotor rotational frequency of the rotor 130 around its rotor axis R , a rotor (rotary) position, an amplitude of a blade angle adjustment to support a wind tracking movement by the tracking drive and, based on the rotor rotational frequency, a phase shift of the amplitude relative to a rotor-fixed reference angle position, which it determines based on the rotor (rotary) position. The amplitude can be, for example, a stored, constant or read reference value from a map.

In one step S240 adjusts the control 100 the blade angles cyclically with the determined amplitude and the phase shift.

Has a specified waiting time passed since the activation of this blade angle adjustment ( S250 : " Y “), It controls in one step S260 the tracking drive 20th so that he's the gondola 120 and with it the rotor 130 around the yaw axis G twisted in such a way that the deviation is reduced.

Although exemplary embodiments have been explained in the preceding description, it should be pointed out that a large number of modifications are possible.

So the procedure or system of execution of the 2nd explained using a one-step reduction when the (first) lower reduction speed limit is exceeded. In modifications that are not shown, one or more further reduction and / or one or more increase stages can also be provided analogously when the speed falls below one or more upper increase limits.

The procedure or system of executing the 3rd has a determination of the amplitude of the blade angle adjustment both as a function of a rotor torque (cf. steps S150 , S155 ) and a wind tracking direction of the rotor around the yaw axis (see steps S140 , S145 ) and a lead angle depending on the amplitude (see steps S160 ), whereby one or two of these features can be omitted in modifications not shown.

The procedure or system of executing the 4th shows a waiting time (see step S250 ) as well as a dynamically adjusted commanded phase shift (see steps S230 , S240 ), whereby one of these features can be omitted in modifications not shown.

It should also be pointed out that the exemplary embodiments are only examples that are not intended to restrict the scope of protection, the applications and the structure in any way. Rather, the above description gives the person skilled in the art a guideline for the implementation of at least one exemplary embodiment, it being possible for various changes, in particular with regard to the function and arrangement of the described components, to be carried out without leaving the scope of protection as it is the claims and these equivalent combinations of features.

In particular, individual aspects of the present invention, in particular the reduction or analog increase in the amplitude in a reduction or increase speed range (cf. in particular 2nd and associated description), the adjustment of the amplitude depending on a rotor torque or a wind tracking direction or the adjustment of the blade angle by the lead angle (cf. in particular 3rd and associated description), and the activation of the tracking drive by a predetermined waiting time after the blade angle adjustment (delayed) or the commanded phase shift dynamically adjusted as a function of a rotor rotational frequency (cf. in particular 4th and associated description), explained above on the basis of various designs, wherein two or more of these aspects or the features or designs described above can also be advantageously combined.

For example, the above-described reduction and / or increase in the amplitude in a reduction or increase speed range can be implemented in addition to the adjustment of the amplitude as a function of a rotor torque and / or a wind tracking direction and / or the adjustment of the blade angles by the lead angle . Additionally or alternatively, for example, the reduction and / or increase in amplitude explained above in a reduction or increase speed range can be carried out in addition to the activation of the tracking drive by a predetermined waiting time after the blade angle adjustment and / or the commanded phase shift dynamically adjusted depending on a rotor rotational frequency be realized. Additionally or alternatively, the above-described adjustment of the amplitude as a function of a rotor torque and / or a wind tracking direction and / or the adjustment of the blade angles by the lead angle in addition to the activation of the tracking drive by a predetermined waiting time after the blade angle adjustment and / or depending commanded phase shift dynamically adjusted by a rotor rotational frequency.

Reference symbol list

10th

Wind vane

20th

Tracking drive

30th

Rotor blade

100

control

110

tower

120

gondola

130

rotor

140

Generator (gear unit)

150

power grid

B

Blade axis

G

Yaw axis

R

Rotor axis

Claims (7)

Method for operating a wind power plant which has a rotor (130) which can be rotated about a rotor axis (R) and has at least two rotor blades (30) which can be individually adjusted about its blade axis (B) has a tracking drive (20) for wind tracking the rotor about a yaw axis (G), wherein in a tracking operating mode, blade angles of the rotor blades are adjusted about their blade axis to support a wind tracking movement by the tracking drive (S40, S60), with an amplitude of this blade angle adjustment - Reduced by or to a predetermined value (S55) if a yaw rate of the rotor about the yaw axis lies in a predetermined reduction speed range which has a lower reduction speed limit; and or - Is increased by or to a predetermined value if a yaw rate of the rotor about the yaw axis lies in a predetermined increase speed range which has an upper increase speed limit. Procedure according to Claim 1 , characterized in that, in the tracking operating mode, the amplitude of the blade angle adjustment to support a wind tracking movement by the tracking drive - is reduced by or to a predetermined value if the yaw rate is within a predetermined second reduction speed range which has a second lower reduction speed limit; and / or - is increased by or to a predetermined value if the yaw rate is in a predetermined second increase speed range which has a second upper increase speed limit. Method according to one of the preceding claims, characterized in that in the follow-up operating mode - at least one, in particular at least two, and / or at most four reduction speed ranges, in particular exactly one or two reduction speed ranges, are provided, for which the amplitude of the blade angle adjustment is speed range-specific is reduced; and / or - at least one, in particular at least two, and / or at most four, increase speed ranges, in particular exactly one or two increase speed ranges, for which the amplitude of the blade angle adjustment is increased in each case specific to the speed range. Method according to one of the preceding claims, characterized in that a speed range extends over at least 0.05 ° per second. Method according to one of the preceding claims, characterized by the steps: - determining (S10) a wind tracking requirement; - Determining (S30) the amplitude of the blade angle adjustment to support the wind tracking movement by the tracking drive; - Setting (S40) the individual blade angles of the rotor blades based on this amplitude - Determining (S40) an actual value of the yaw rate of the rotor about the yaw axis; - Step-by-step reduction (S55) of the determined amplitude if the actual value exceeds one or more predetermined speed limits; and / or incrementally increasing the determined amplitude if the actual value falls below one or more predetermined speed limits; and - setting (S60) the individual blade angles of the rotor blades based on this amplitude. System for operating a wind energy installation, comprising a rotor (130) rotatable about a rotor axis (R) with at least two rotor blades (30) individually adjustable about their blade axis (B) and one Has tracking drive (20) for wind tracking of the rotor around a yaw axis (G), the system being set up for carrying out a method according to one of the preceding claims and / or comprising: means for adjusting blade angles of the rotor blades about their blade axis to support a wind tracking movement by the tracking drive in a tracking operating mode and - means for reducing an amplitude of this blade angle adjustment by or to a predetermined value if a yaw rate of the rotor around the yaw axis is in a predetermined reduction speed range which has a lower reduction speed limit; and / or - means for increasing an amplitude of this blade angle adjustment by or to a predetermined value if a yaw rate of the rotor about the yaw axis is in a predetermined increase speed range which has an upper increase speed limit. Computer program product with a program code, which is stored on a medium readable by a computer, for carrying out a method according to one of the preceding claims.

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