Abstract: Bearing arrangement of a wind turbine, including a bearing with an outer ring and an inner ring and a lubrication fluid provided between both rings, and at least one sealing means arranged at each side of the bearing for sealing the gap between the outer and the inner ring, whereby each sealing means is fixed to one ring and contacts the other ring with a flexible lip-like sealing element, wherein a pressure device for at least temporarily providing a gas overpressure in the sealed gap for increasing the contact load of the lip-like sealing element to the ring is provided.

Abstract: Provided is a method of machining a bearing ring of a wind turbine bearing, the method including the steps of identifying a number of local hard zones on a surface of the bearing ring and removing material from the surface such that a bearing ring thickness in local hard zone is less than a bearing ring thickness outside a local hard zone. A machining assembly, a wind turbine bearing and a wind turbine is also provided.

Abstract: Bearing arrangement of a wind turbine, including a bearing with an outer ring and an inner ring and a lubrication fluid provided between both rings, and at least one sealing means arranged at each side of the bearing for sealing the gap between the outer and the inner ring, whereby each sealing means is fixed to one ring and contacts the other ring with a flexible lip-like sealing element, wherein a pressure device for at least temporarily providing a gas overpressure in the sealed gap for increasing the contact load of the lip-like sealing element to the ring is provided.

Abstract: A method of monitoring a blade pitch bearing of a rotor blade of a wind turbine is provided, the method including: pitching the rotor blade; measuring an amount of a vibration of the blade pitch bearing during the pitching; estimating a condition of the blade pitch bearing based on the measured amount of vibration. Also disclosed is an arrangement for monitoring a blade pitch bearing, a rotor blade bearing and a wind turbine.

Abstract: Provided is a method of machining a bearing ring of a wind turbine bearing, the method including the steps of identifying a number of local hard zones on a surface of the bearing ring and removing material from the surface such that a bearing ring thickness in local hard zone is less than a bearing ring thickness outside a local hard zone. A machining assembly, a wind turbine bearing and a wind turbine is also provided.

Abstract: A method of monitoring the amount of lubricant inside a bearing of a wind turbine is provided. The bearing includes a lubricant for reducing wear and fatigue of the bearing, a seal for minimizing the amount of lubricant which is leaking out of the bearing, a ventilation device with at least one pressure compensation hole for enabling a pressure compensation between the sealed bearing and the ambient, and a lubricant drain hole for enabling lubricant to exit the bearing in a controlled manner. The method includes the steps of blowing a compressed medium through the pressure compensation hole into the bearing; measuring the pressure inside the bearing; and determining the amount of lubricant inside the bearing based on the measured pressure.

Abstract: A method of monitoring a blade pitch bearing of a rotor blade of a wind turbine is provided, the method including: pitching the rotor blade; measuring an amount of a vibration of the blade pitch bearing during the pitching; estimating a condition of the blade pitch bearing based on the measured amount of vibration. Also disclosed is an arrangement for monitoring a blade pitch bearing, a rotor blade bearing and a wind turbine.

Abstract: A method of monitoring the amount of lubricant inside a bearing of a wind turbine is provided. The bearing includes a lubricant for reducing wear and fatigue of the bearing, a seal for minimizing the amount of lubricant which is leaking out of the bearing, a ventilation device with at least one pressure compensation hole for enabling a pressure compensation between the sealed bearing and the ambient, and a lubricant drain hole for enabling lubricant to exit the bearing in a controlled manner. The method includes the steps of blowing a compressed medium through the pressure compensation hole into the bearing; measuring the pressure inside the bearing; and determining the amount of lubricant inside the bearing based on the measured pressure.

Abstract: A bearing of a wind turbine, wherein the bearing is lubricated with a lubricant for reducing wear and fatigue of the bearing, the bearing is sealed such that the amount of lubricant which is leaking out of the bearing is minimized, is provided. The bearing includes a ventilation device with at least one pressure compensation hole for enabling a pressure compensation between the sealed bearing and the ambient. The ventilation device further includes a compressor unit, which is connected with the pressure compensation hole. Thus, a compressed medium can be selectively blown through the pressure compensation hole to ensure that the pressure compensation hole remains substantially unobstructed such that overpressure within the bearing compared to the ambient is minimized and leakage of lubricant out of the bearing is reduced. A wind turbine including such bearing and an associated method is also provided.

Abstract: A bearing of a wind turbine, wherein the bearing is lubricated with a lubricant for reducing wear and fatigue of the bearing, the bearing is sealed such that the amount of lubricant which is leaking out of the bearing is minimized, is provided. The bearing includes a ventilation device with at least one pressure compensation hole for enabling a pressure compensation between the sealed bearing and the ambient. The ventilation device further includes a compressor unit, which is connected with the pressure compensation hole. Thus, a compressed medium can be selectively blown through the pressure compensation hole to ensure that the pressure compensation hole remains substantially unobstructed such that overpressure within the bearing compared to the ambient is minimized and leakage of lubricant out of the bearing is reduced. A wind turbine including such bearing and an associated method is also provided.

Abstract: The invention relates to a method of condition monitoring of a wind turbine. Measurement data and operating condition parameters are captured. A subset of the operating condition parameters is selected. A set of n characterizing moments is calculated based on the subset of operating condition parameters. A finite n-dimensional space each representing possible values for one of the characterising moments is provided. The n-dimensional space is sub-divided into a number of bins each representing a n-dimensional interval defined by n one-dimensional intervals. Each one- dimensional intervals represents an interval in one of the n dimensions. Each bin defines an acceptable range for the set of n characterizing moments. The set of the characterising moments is determined if it belongs to one of the bins. The set of the characterising moments and measurement data are accepted if the set of the characterising moments belongs to one of the bins.

Abstract: In one aspect, an alarm mask for condition monitoring in a wind turbine is automatically generated. A reference data selecting definition is selected from a control definition repository in the wind turbine. The reference data selecting definition specifies a time interval of recorded reference data. Reference data is selected from a sensor located in the wind turbine recorded during the time interval. A reference value is calculated based on the reference data. A first and a second alarm mask factor are selected from the control definition repository. A first alarm mask is calculated based on multiplying the first alarm mask factor and the reference value. A second alarm mask is calculated based on multiplying the second alarm mask factor by the reference value.

Abstract: Method and apparatus for vibration-based automatic condition monitoring of a wind turbine, comprising the steps of: determining a set of vibration measurement values of the wind turbine; calculating a frequency spectrum of the set of vibration measurement values; calculating a cepstrum of the frequency spectrum; selecting at least one quefrency in the cepstrum, and detecting an alarm condition based upon an amplitude of the cepstrum at the selected quefrency, and a wind turbine therefor.

Abstract: The invention relates to a method of condition monitoring of a wind turbine. Measurement data and operating condition parameters are captured. A subset of the operating condition parameters is selected. A set of n characterizing moments is calculated based on the subset of operating condition parameters. A finite n-dimensional space each representing possible values for one of the characterising moments is provided. The n-dimensional space is sub-divided into a number of bins each representing a n-dimensional interval defined by n one-dimensional intervals. Each one-dimensional intervals represents an interval in one of the n dimensions. Each bin defines an acceptable range for the set of n characterizing moments. The set of the characterising moments is determined if it belongs to one of the bins. The set of the characterising moments and measurement data are accepted if the set of the characterising moments belongs to one of the bins.

Abstract: In one aspect, an alarm mask for condition monitoring in a wind turbine is automatically generated. A reference data selecting definition is selected from a control definition repository in the wind turbine. The reference data selecting definition specifies a time interval of recorded reference data. Reference data is selected from a sensor located in the wind turbine recorded during the time interval. A reference value is calculated based on the reference data. A first and a second alarm mask factor are selected from the control definition repository. A first alarm mask is calculated based on multiplying the first alarm mask factor and the reference value. A second alarm mask is calculated based on multiplying the second alarm mask factor by the reference value.

Abstract: Method and apparatus for vibration-based automatic condition monitoring of a wind turbine, comprising the steps of: determining a set of vibration measurement values of the wind turbine; calculating a frequency spectrum of the set of vibration measurement values; calculating a cepstrum of the frequency spectrum; selecting at least one quefrency in the cepstrum, and detecting an alarm condition based upon an amplitude of the cepstrum at the selected quefrency, and a wind turbine therefor.