Abstract: A method is provided for locating a lightning strike at a wind turbine including the following steps, detecting a lightning strike, and deriving a location of the lightning strike based on a measurement of sound caused by the lightning strike. Further, a lightning detection system, a wind turbine, a wind farm as well as a computer program product and a computer readable medium are suggested for performing the method.

Abstract: A lightning protection system of a wind turbine is provided, including a blade lightning conductor arranged in a rotor blade of the wind turbine to extend into the hub, a stationary conductor to provide a blade grounding path to ground during a lighting strike, a brush arranged to electrically connect the blade lightning conductor and the stationary conductor, and a discharge means arranged to provide a separate discharge path from the blade lightning conductor to ground. Furthermore, a wind turbine, and a method of equipping a wind turbine with a lightning protection system, is also provided.

Abstract: A method is provided for locating a lightning strike at a wind turbine including the following steps, detecting a lightning strike, and deriving a location of the lightning strike based on a measurement of sound caused by the lightning strike. Further, a lightning detection system, a wind turbine, a wind farm as well as a computer program product and a computer readable medium are suggested for performing the method.

Abstract: A bearing arrangement to avoid a static charge in a bearing is provided. A bearing arrangement for a wind turbine comprises a first bearing shell that is prepared to be coupled to a first part of the wind turbine. The bearing arrangement comprises a second bearing shell that is prepared to be coupled to a second part of the wind turbine. The first and the second bearing shell are arranged in a way that the first and the second bearing shell are rotatable with respect to each other and have a first isolation ring for electrical isolation, so that the first part of the wind turbine can be rotated with respect to the second part of the wind turbine and avoid static discharge.

Abstract: A bearing arrangement to avoid a static charge in a bearing is provided. A bearing arrangement for a wind turbine comprises a first bearing shell that is prepared to be coupled to a first part of the wind turbine. The bearing arrangement comprises a second bearing shell that is prepared to be coupled to a second part of the wind turbine. The first and the second bearing shell are arranged in a way that the first and the second bearing shell are rotatable with respect to each other and have a first isolation ring for electrical isolation, so that the first part of the wind turbine can be rotated with respect to the second part of the wind turbine and avoid static discharge.

Abstract: A method is provided for measuring the condition of the lubrication in a bearing of a wind turbine. The bearing includes a first bearing shell and a second bearing shell and a layer of lubrication between the first and the second bearing shell. The method involves at least the steps of: applying a voltage from a voltage source to the bearing shells such that an electrical potential is building up between the bearing shells, increasing the level of the voltage applied to the bearing shells until the break down voltage of the layer of lubrication is reached, and measuring the voltage applied to the bearing shells to detect and measure the value of the break-down voltage of the layer of lubrication in the bearing.

Abstract: The present invention relates to a wind turbine facility comprising a power generator operationally connected to an AC/AC converter adapted to receive variable frequency AC-power from the power generator, and adapted to generate substantially fixed frequency AC-power. The wind turbine facility further comprises a harmonic filter system, and a grid transformer comprising a primary winding being operationally connected to the AC/AC converter, and a secondary winding adapted to be operationally connected to an associated, substantially fixed frequency AC-power supply grid. The grid transformer further comprises a tertiary winding being operationally connected to the harmonic filter in order to suppress unwanted harmonics, such as selected harmonics generated by the AC/AC converter. The turn ratio between the primary and tertiary windings is selected in such a manner that a voltage of the tertiary winding is lower than a nominal voltage level of the associated AC-power supply grid voltage.

Abstract: The invention provides a wind turbine with a lightning arrester system including one or more lightning receptors (R) mounted on one or more rotor blades. A down conductor electrically connects one or more lightning receptors (R) to electrical ground via a sliding contact arrangement (SC), and an electromagnetic radiation (EM) reduction device encircles a portion of the down conductor so as to reduce EM radiation from the down conductor due to static electric discharges caused by imperfect electric contact in the sliding contact arrangement (SC). Known types of EM radiation reduction devices in the form of commercially available common mode choke coils, cylindrically shaped nano-crystalline solid body types, or the like, can be used. A plurality of different types with different EM radiation reduction properties can be used in combination. To obtain more effective EM radiation reduction, a plurality of EM radiation reduction devices can be used, e.g.

Abstract: A wind turbine comprising a wind turbine rotor with at least one wind turbine blade, a wind turbine tower, such as a standard tubular steel tower, positioned on a foundation and connected to the wind turbine rotor through a wind turbine nacelle, and a control for establishing oscillation control values of the wind turbine. The wind turbine being capable of altering the load for optimizing the tower eigenfrequency in response to acquired values from the controls. The invention also relates to a control system and method for altering the eigenfrequency of a tower of a wind turbine.

Abstract: The invention relates to a protection system for an electric generator of a wind turbine comprising at least one current path from the non drive end of the generator shaft to a ground potential, and at least one alternating current path from the drive end of the generator shaft to the ground potential. The invention also relates to a wind turbine and use hereof.