Abstract: The invention relates to a method for monitoring the vibrational state of a wind turbine comprising detecting a plurality of acceleration values that represent accelerations which a component of the wind turbine is subject to at different respective points in time within a specified time interval, storing the acceleration values in an acceleration data set; generating a sum frequency distribution on the basis of the acceleration data set, comparing a first sum frequency value of the sum frequency distribution with a second sum frequency value of a threshold sum frequency distribution for at least one acceleration value, and outputting a warning signal if the second sum frequency value is greater than the first sum frequency value.

Abstract: The invention relates to a heavy-duty upgrading method for rotor blades of existing wind turbines and to a plastic membrane used in the method according to the invention, wherein the rotor blades are covered and/or extended in that at least one fibre-reinforced or fabric-reinforced plastic membrane is fitted onto an outer surface of the original aerodynamic profile of the rotor blade being upgraded and the original contour of the rotor blade being upgraded is then joined to the upgraded rotor blade.

Abstract: The invention relates to a method for monitoring the vibrational state of a wind turbine comprising detecting a plurality of acceleration values that represent accelerations which a component of the wind turbine is subject to at different respective points in time within a specified time interval, storing the acceleration values in an acceleration data set; generating a sum frequency distribution on the basis of the acceleration data set, comparing a first sum frequency value of the sum frequency distribution with a second sum frequency value of a threshold sum frequency distribution for at least one acceleration value, and outputting a warning signal if the second sum frequency value is greater than the first sum frequency value.

Abstract: A gear mechanism (22) of a wind power plant (10) that includes at least one planetary stage (24.1, 24.2) that has at least one planet gear carrier (41, 61) and a method for dismantling a multi-stage gear mechanism (22) of a wind power plant (10). The gear mechanism (22) is arranged in a nacelle (15) arranged on a tower (11) of a wind power plant (10). The gear mechanism (22) has at least one planetary stage (24.1, 24.2) and the at least one planetary stage (24.1, 24.2) has a planet gear carrier (41, 61) and several planet gears (45, 65) held in the planet gear carrier (41, 61) using planetary bolts (47, 67). The planet gears (45, 65) are in operative connection with a ring gear (49, 69) of the planetary stage (24.1, 24.2) surrounding the planet gears (45, 65).

Abstract: A multi-stage gear box (122) of a wind power plant, wherein the gear box (122) includes a gear box housing (125). The gear box (122) includes at least one access opening for the insertion of a work instrument into the gear box housing (125) or respectively into the interior of the gear box housing (125) is provided on the outside of the gear box housing (125) and in that at least one guiding device (201, 202, 203, 204, 205) is provided for the work instrument inside the gear box housing (125) so that the work instrument is moveable and/or positionable within the guiding device (201, 202, 203, 204, 205). Parts of the gear box (122) in the gear box housing (125) are checked and/or worked by a work instrument inserted or arranged or arrangeable in the guiding device (201, 202, 203, 204, 205).

Abstract: A gear mechanism (22) of a wind power plant (10) that includes at least one planetary stage (24.1, 24.2) that has at least one planet gear carrier (41, 61) and a method for dismantling a multi-stage gear mechanism (22) of a wind power plant (10). The gear mechanism (22) is arranged in a nacelle (15) arranged on a tower (11) of a wind power plant (10). The gear mechanism (22) has at least one planetary stage (24.1, 24.2), and the at least one planetary stage (24.1, 24.2) has a planet gear carrier (41, 61) and several planet gears (45, 65) held in the planet gear carrier (41, 61) using planetary bolts (47, 67). The planet gears (45, 65) are in operative connection with a ring gear (49, 69) of the planetary stage (24.1, 24.2) surrounding the planet gears (45, 65).

Abstract: A gear box (122) of a wind power plant, in particular a multi-stage gear box (122) of a wind power plant, wherein the gear box (122) includes a gear box housing (125). Furthermore, a wind power plant and use of a work instrument. The gear box (122) is further developed in that at least one access opening for the insertion of a work instrument into the gear box housing (125) or respectively into the interior of the gear box housing (125) is provided on the outside of the gear box housing (125) and in that at least one guiding means (201, 202, 203, 204, 205) is provided for the work instrument inside the gear box housing (125) so that the work instrument is moveable and/or positionable within the guiding means (201, 202, 203, 204, 205), wherein in particular parts of the gear box (122) in the gear box housing (125) are checked and/or worked by means of the work instrument inserted or arranged or arrangeable in the guiding means (201, 202, 203, 204, 205).