Abstract: The present invention relates to a control method and a wind turbine configured to determine a load signal of at least one component of the wind turbine, and to calculate a damage rate based on this load signal. The control method calculates and monitors the damage rate in real-time, wherein the damage rate is normalised by using a first function defining a first transition phase. A second function is afterwards applied to the normalised damage rate which defines a second transition phase. These transition phases allows for a smooth transition between different operating modes of the wind turbine. The control method may further change the power output of the wind turbine relative to the nominal power output when the output signal of the second function is determined to be stable over at least one time period.

Abstract: The present invention relates to a control method and a wind turbine configured to determine a load signal of at least one component of the wind turbine, and to calculate a damage rate based on this load signal. The control method calculates and monitors the damage rate in real-time, wherein the damage rate is normalised by using a first function defining a first transition phase. A second function is afterwards applied to the normalised damage rate which defines a second transition phase. These transition phases allows for a smooth transition between different operating modes of the wind turbine. The control method may further change the power output of the wind turbine relative to the nominal power output when the output signal of the second function is determined to be stable over at least one time period.

Abstract: A method for determining an equivalent mechanical load of a component includes a dynamic mechanical loading. A first measurement value of the mechanical load of the component is measured and compared to a first reference value. Further, at least one count value representing the number of load half-cycles of the component is updated based upon the result of comparing, wherein the load half-cycles correspond to a predetermined range of mechanical loads and occur within a time period prior to the measurement of the first measurement value. A first equivalent mechanical load of the component is determined based on the first updated count value. It is further described a program element and a computer-readable medium having stored a program for controlling the described equivalent mechanical load determining method.

Abstract: A method of molding a wind-turbine blade in a mold is described. The method includes arranging a number of markers on an interior of the mold; arranging a composite layup in the mold; and assembling and curing the composite layup in the mold such that a negative impression of a marker is formed on a surface of the composite layup, which negative impression facilitates correct positioning of the blade relative to a component in a subsequent assembly step. A mold for molding a wind-turbine blade; a wind-turbine blade molded using such a mold; and a positioning device for positioning a drilling and/or milling tool relative to a root portion of a wind-turbine blade molded using the inventive method are disclosed. A method of manufacturing a wind-turbine blade is also disclosed.

Abstract: A method for aligning a wind turbine with the wind direction is provided. The method includes measuring at least one first pressure at a first side of the wind turbine's nacelle, determining the pressure difference between the measured first pressure and a second pressure, and rotating the nacelle in dependence to the determined pressure difference. A wind turbine arrangement including a nacelle, a yaw alignment controller, and a yaw drive is also provided.

Abstract: A method is provided for detecting a blade pitch angle unbalance of a rotor blade system of a wind turbine, the rotor blade system rotating around a rotor rotation axis. The method includes yawing the rotor rotation axis about a yawing axis transverse to the rotor rotation axis. The method also includes obtaining a load signal indicative of a load due to the yawing. The method further includes analyzing the load signal regarding a frequency component of the load signal, and detecting the blade pitch angle unbalance based on the analyzed load signal.

Abstract: A method of moulding a wind-turbine blade in a mould is described. The method includes arranging a number of markers on an interior of the mould; arranging a composite layup in the mould; and assembling and curing the composite layup in the mould such that a negative impression of a marker is formed on a surface of the composite layup, which negative impression facilitates correct positioning of the blade relative to a component in a subsequent assembly step. A mould for moulding a wind-turbine blade; a wind-turbine blade moulded using such a mould; and a positioning device for positioning a drilling and/or milling tool relative to a root portion of a wind-turbine blade moulded using the inventive method are disclosed. A method of manufacturing a wind-turbine blade is also disclosed.

Abstract: An elongated member of a wind turbine is disclosed which is potentially subject to strain and which comprises a sensor unit for determining the deflection and/or strain of the elongated member between a first point and a second point, which are assigned to the same side of the elongated member, and the sensor unit comprises a proximity sensor for determining the distance between the second point and a third point, the third point being connected to the first point by an inflexible support, the distance between the first point and the third point being considerably longer than the distance between the second point and the third point, wherein the sensor unit comprises a compressible and/or stretchable element located between the second point and the third point. Moreover, a wind turbine rotor blade and a tower of a wind turbine, each comprising a previously described elongated member, are disclosed.

Abstract: A method for determining an equivalent mechanical load of a component includes a dynamic mechanical loading. A first measurement value of the mechanical load of the component is measured and compared to a first reference value. Further, at least one count value representing the number of load half-cycles of the component is updated based upon the result of comparing, wherein the load half-cycles correspond to a predetermined range of mechanical loads and occur within a time period prior to the measurement of the first measurement value. A first equivalent mechanical load of the component is determined based on the first updated count value. It is further described a program element and a computer-readable medium having stored a program for controlling the described equivalent mechanical load determining method.

Abstract: A method for determining the deflection and/or strain of an elongated member of a component is provided, in which a first point and a second point are assigned to the same side of an elongated member of the component, wherein the deflection and/or strain of the elongated member is determined by determining the distance between the second point and a third point, which is connected to the first point by an inflexible support, whereby the distance between the first point and the third point is considerably longer than the distance between the second point and the third point, and wherein the distance between the second point and the third point is determined in time steps and the frequency of the change of the distance is analyzed to detect frequency changes. Furthermore, an elongated member of a component subject to strain and comprises a sensor unit for determining the deflection and/or strain of the elongated member.

Abstract: In one aspect, a method for aligning a component into a wind direction is provided. The component comprises a sensor which is located such that at least part of the sensor is exposed to the wind. A signal is measured based on the force acting on the sensor due to the wind, and the component is rotated depending on the measured signal. Additionally a sensor for determining misalignment of a component relative to a wind direction is provided. The sensor comprises at least one flat element and at least one tool or device for measuring the force acting on the flat element.

Abstract: A method for measuring the pitch angle of a wind turbine rotor blade is provided. In the method at least one image of at least part of the rotor blade is acquired by a camera from a defined position and the pitch angle is calculated by means of data from the at least one image.

Abstract: A method for aligning a wind turbine with the wind direction is provided. The method includes measuring at least one first pressure at a first side of the wind turbine's nacelle, determining the pressure difference between the measured first pressure and a second pressure, and rotating the nacelle in dependence to the determined pressure difference. A wind turbine arrangement including a nacelle, a yaw alignment controller, and a yaw drive is also provided.

Abstract: A blade for a wind turbine is provided. The blade includes a blade surface and a pressure gauge device for providing a pressure value being used for stall detection. The pressure gauge device is located at the blade surface such that a pressure of a fluid flowing along the blade surface is measured by the pressure gauge device.

Abstract: In one aspect, a method for aligning a component into a wind direction is provided. The component comprises a sensor which is located such that at least part of the sensor is exposed to the wind. A signal is measured based on the force acting on the sensor due to the wind, and the component is rotated depending on the measured signal. Additionally a sensor for determining misalignment of a component relative to a wind direction is provided.

Abstract: A method for determining the deflection and/or strain of an elongated member of a component is provided, in which a first point (16) and a second point (17) are assigned to the same side (11, 12) of an elongated member of the component, wherein the deflection and/or strain of the elongated member is determined by determining the distance between the second point (17) and a third point (18), which is connected to the first point (16) by an inflexible support (5), whereby the distance between the first point (16) and the third point (18) is considerably longer than the distance between the second point (17) and the third point (18), and wherein the distance between the second point (17) and the third point (18) is determined in time steps and the frequency of the change of the distance is analysed to detect frequency changes.

Abstract: An elongated member of a wind turbine is disclosed which is potentially subject to strain and which comprises a sensor unit for determining the deflection and/or strain of the elongated member between a first point and a second point, which are assigned to the same side of the elongated member, and the sensor unit comprises a proximity sensor for determining the distance between the second point and a third point, the third point being connected to the first point by an inflexible support, the distance between the first point and the third point being considerably longer than the distance between the second point and the third point, wherein the sensor unit comprises a compressible and/or stretchable element located between the second point and the third point. Moreover, a wind turbine rotor blade and a tower of a wind turbine, each comprising a previously described elongated member, are disclosed.

Abstract: Wind turbine blade (10) including adjustable lift-regulating means (12, 13, 15, 17, 19, 21) arranged on or at the surface of the wind turbine blade (10), said lift-regulating means being provided with activating means by means of which they can be adjusted and thus alter the aerodynamic properties of the blade (10). The lift-regulating means (12, 13, 15, 17, 19, 21) and the activating means are adapted and arranged such that by activation of the activating means, the lift can be reduced in a zone extending in the longitudinal direction of the blade (10) from a first position adjacent the blade tip (14) to a second position between the position and the blade root (16) and this second position is variable in the longitudinal direction of the blade (10) by adjusting activate means. The lift-regulating means are formed of at least one flexible flap (12, 13, 15, 17, 19, 21).

Abstract: Wind turbine blade (10) including adjustable lift-regulating means (12, 13, 15, 17, 19, 21) arranged on or at the surface of the wind turbine blade (10), said lift-regulating means being provided with activating means by means of which they can be adjusted and thus alter the aerodynamic properties of the blade (10). The lift-regulating means (12, 13, 15, 17, 19, 21) and the activating means are adapted and arranged such that by activation of the activating means, the lift can be reduced in a zone extending in the longitudinal direction of the blade (10) from a first position adjacent the blade tip (14) to a second position between the first position and the blade root (16) and this second position is variable in the longitudinal direction of the blade (10) by adjusting the activate means. The lift-regulating means are formed of at least one flexible flap (12, 13, 15, 17, 19, 21).

Abstract: A wind turbine rotor blade (10) comprising one or more means (4) secured to the blade (10) for changing the profile thereof depending on the atmospheric temperature. The means comprises at least one laminate having at least two layers of materials with differing thermal expansion coefficients.