Abstract: A method for operating a wind turbine having at least one blade includes determining an ambient air operating envelope and controlling a power output of the wind turbine at least partially based on the determined ambient air operating envelope. Determining an ambient air operating envelope includes measuring at least one of an ambient air temperature, an ambient air pressure, an ambient air humidity, and wind turbine power output. The method also includes comparing at least one of a measured ambient air temperature, a measured ambient air humidity and a measured ambient air pressure to predetermined ambient air temperature, pressure and humidity values. The method further includes referencing the predetermined ambient air temperature, pressure and humidity values to at least one operational parameter of the wind turbine. The method also includes determining if an existing wind turbine power output is within a range associated with the determined ambient air operating envelope.

Abstract: A compact filter has a compact filter element for exchangeable use in a filter housing and the compact filter element has a filter body of a web-shaped filter medium. The web-shaped filter medium has at least one flat filter medium web and one corrugated filter medium web that are placed onto each other and at least partially connected to each other by ultrasonic welding. At least one of the flat and corrugated filter medium webs is a composite filter medium web of at least two components, wherein at least one component is a synthetic material and one component is a non-synthetic material. The non-synthetic material is a plant-derived material and forms a support of the composite filter medium web and the synthetic material is a synthetic layer applied on the support.

Abstract: The invention relates to a compact filter element (1) for exchangeable use in a filter housing (2). The compact filter element (1) has a filter body (3) with a longitudinal axis (7) and at least one seal (4) arranged in the area of a front end (5) of the filter body (3), the seal having a seal section (8) which is arranged across the width (10) of a housing wall (6), sealing same. The seal section (8) projects beyond a front surface (12) of the filter body (3) in the direction of the longitudinal axis (7). The seal section (8) has a peripheral support wall (9) and at least one seal lip (17) integrally bonded to the outside of the support wall (9), across the width (10) of the latter, wherein the support wall (9) and the seal lip (17) consist of a rubber elastic material.

Abstract: A compact filter has a compact filter element for exchangeable use in a filter housing and the compact filter element has a filter body of a web-shaped filter medium. The web-shaped filter medium has at least one flat filter medium web and one corrugated filter medium web that are placed onto each other and at least partially connected to each other by ultrasonic welding. At least one of the flat and corrugated filter medium webs is a composite filter medium web of at least two components, wherein at least one component is a synthetic material and one component is a non-synthetic material. The non-synthetic material is a plant-derived material and forms a support of the composite filter medium web and the synthetic material is a synthetic layer applied on the support.

Abstract: A method for controlling a wind energy system is provided wherein the method comprises determining the effective wind speed taking into account the load on the rotor blades of said wind energy system exerted by the wind is provided. A computer-readable medium is provided that provides instructions which when executed by a computing platform cause the computing platform to perform operations wherein the operations include the method according to embodiments described herein. Further, a wind energy system having a calculation unit adapted for calculating the effective wind speed by taking into account the load on the rotor blades of said wind energy system exerted by the wind is provided. Further, a wind speed sensor free wind energy system having a generator for generating electric energy and a controller for shutting down and/or starting the electric energy generation in dependence of the wind speed is provided.

Abstract: A method for controlling a wind energy system is provided wherein the method comprises determining the effective wind speed taking into account the load on the rotor blades of said wind energy system exerted by the wind is provided. A computer-readable medium is provided that provides instructions which when executed by a computing platform cause the computing platform to perform operations wherein the operations include the method according to embodiments described herein. Further, a wind energy system having a calculation unit adapted for calculating the effective wind speed by taking into account the load on the rotor blades of said wind energy system exerted by the wind is provided. Further, a wind speed sensor free wind energy system having a generator for generating electric energy and a controller for shutting down and/or starting the electric energy generation in dependence of the wind speed is provided.

Abstract: A filter device has a compact filter made of a filter material that is wound spirally. A star filter that is made of a filter material that has folds arranged in a star shape surrounds the compact filter. The filter device has a cylindrical shape. A fluid to be filtered passes the compact filter in an axial direction and the star filter in a radial direction. The filter device is exchangeable and is mounted in a filter housing such that the compact filter and the star filter have a common raw side and a common clean side that are separated from each other.

Abstract: The present patent application concerns an apparatus for cleaning an outer surface of a rotor blade of a wind turbine, the apparatus comprising a first frame and a cleaning device, the cleaning device being adapted to conform to the outer surface and connected to the first frame, wherein the apparatus is adapted to be slidably positioned on the outer surface of the rotor blade, to slide along, and to be pressed onto the outer surface. Further, it concerns an apparatus for cleaning a leading edge of a rotor blade of a wind turbine, the apparatus comprising a first frame and a cleaning device, the cleaning device being adapted to conform to the leading edge and being connected to the first frame, wherein the apparatus is adapted to be slidably positioned on the leading edge of the rotor blade, to slide along and to be pressed onto the leading edge during standstill of a wind rotor comprising the rotor blade.

Abstract: A method for controlling a wind energy system is provided wherein the method comprises determining the effective wind speed taking into account the load on the rotor blades of said wind energy system exerted by the wind is provided. A computer-readable medium is provided that provides instructions which when executed by a computing platform cause the computing platform to perform operations wherein the operations include the method according to embodiments described herein. Further, a wind energy system having a calculation unit adapted for calculating the effective wind speed by taking into account the load on the rotor blades of said wind energy system exerted by the wind is provided. Further, a wind speed sensor free wind energy system having a generator for generating electric energy and a controller for shutting down and/or starting the electric energy generation in dependence of the wind speed is provided.

Abstract: A yaw drive system for a wind energy system includes a hydraulic yaw motor for adjusting the yaw angle of a nacelle of a wind energy system, at least one hydraulic pump adapted for providing a pressurized hydraulic fluid, a hydraulic line system, including at least one line connecting the at least one hydraulic pump and the at least one hydraulic yaw motor, and at least one overpressure valve. The at least one overpressure valve is connected to at least one flow path of the hydraulic fluid between the at least one hydraulic pump and the at least one hydraulic motor. Further, a method for changing a yaw angle of a wind turbine nacelle is provided.

Abstract: The invention relates to a compact filter element (1) for exchangeable use in a filter housing (2). The compact filter element (1) has a filter body (3) with a longitudinal axis (7) and at least one seal (4) arranged in the area of a front end (5) of the filter body (3), the seal having a seal section (8) which is arranged across the width (10) of a housing wall (6), sealing same. The seal section (8) projects beyond a front surface (12) of the filter body (3) in the direction of the longitudinal axis (7). The seal section (8) has a peripheral support wall (9) and at least one seal lip (17) integrally bonded to the outside of the support wall (9), across the width (10) of the latter, wherein the support wall (9) and the seal lip (17) consist of a rubber elastic material.

Abstract: A method for re-calibrating an anemometer of a wind turbine is provided, the method comprising the steps of obtaining pairs of measured values of wind speed and a wind-speed dependent turbine variable; comparing said measured value pairs to pairs of wind speed and the turbine variable obtained from an expected turbine variable curve of the wind turbine to determine a difference between a measured wind speed value and an expected wind speed value for a given turbine variable value; and adjusting a calibration function of said anemometer on the basis of said determined difference.

Abstract: A filter element (1) wound from a plurality of filter layers in which the circumferential contour (5, 5?) of a cross-sectional area (4) of the filter element (1) has at least one circumferential contour section (5?) undercutting the envelope contour (6, 6?) of the cross-sectional filter element area (4).

Abstract: The present patent application concerns an apparatus for cleaning an outer surface of a rotor blade of a wind turbine, the apparatus comprising a first frame and a cleaning device, the cleaning device being adapted to conform to the outer surface and connected to the first frame, wherein the apparatus is adapted to be slidably positioned on the outer surface of the rotor blade, to slide along, and to be pressed onto the outer surface. Further, it concerns an apparatus for cleaning a leading edge of a rotor blade of a wind turbine, the apparatus comprising a first frame and a cleaning device, the cleaning device being adapted to conform to the leading edge and being connected to the first frame, wherein the apparatus is adapted to be slidably positioned on the leading edge of the rotor blade, to slide along and to be pressed onto the leading edge during standstill of a wind rotor comprising the rotor blade.

Abstract: A method for re-calibrating an anemometer of a wind turbine is provided, the method comprising the steps of obtaining pairs of measured values of wind speed and a wind-speed dependent turbine variable; comparing said measured value pairs to pairs of wind speed and the turbine variable obtained from an expected turbine variable curve of the wind turbine to determine a difference between a measured wind speed value and an expected wind speed value for a given turbine variable value; and adjusting a calibration function of said anemometer on the basis of said determined difference.

Abstract: A method for operating a wind turbine having at least one blade includes determining an ambient air operating envelope and controlling a power output of the wind turbine at least partially based on the determined ambient air operating envelope. Determining an ambient air operating envelope includes measuring at least one of an ambient air temperature, an ambient air pressure, an ambient air humidity, and wind turbine power output. The method also includes comparing at least one of a measured ambient air temperature, a measured ambient air humidity and a measured ambient air pressure to predetermined ambient air temperature, pressure and humidity values. The method further includes referencing the predetermined ambient air temperature, pressure and humidity values to at least one operational parameter of the wind turbine. The method also includes determining if an existing wind turbine power output is within a range associated with the determined ambient air operating envelope.

Abstract: A technique for correcting measurement error in data produced by a nacelle-based anemometer and for determining free stream wind speed for a wind turbine involves ascertaining parameters related to the wind turbine and the operation thereof, and using the parameters and data from the nacelle based anemometer as inputs to an algorithm to provide for determination of corrected wind speed data.

Abstract: A filter element (1) wound from a plurality of filter layers in which the circumferential contour (5, 5?) of a cross-sectional area (4) of the filter element (1) has at least one circumferential contour section (5?) undercutting the envelope contour (6, 6?) of the cross-sectional filter element area (4).

Abstract: A technique for correcting measurement error in data produced by a nacelle-based anemometer and for determining free stream wind speed for a wind turbine involves ascertaining parameters related to the wind turbine and the operation thereof, and using the parameters and data from the nacelle based anemometer as inputs to an algorithm to provide for determination of corrected wind speed data.