The invention relates to a method for operating at least a first wind
turbine including the steps of: recording a
tower oscillation, initiating a measure to reduce oscillation if the
tower oscillation is or contains a longitudinal oscillation, and if the amplitude of the longitudinal oscillation exceeds a predefined threshold value, and the measure for reducing the oscillation comprises freezing the current
pitch angle at the current value for a predefined freezing period, switching the
pitch control algorithm used, in particular in such a way that the control speed is reduced, adjusting the
yaw position by a predefined
yaw angle, switching the operation of the first wind
turbine from a first operating mode based on a first power curve to a second operating mode based on a second power curve, and / or if, with regard to the current
wind direction, the first wind
turbine in a
wind park is located behind a second wind turbine, adjusting the rotational speed of the first wind turbine to the rotational speed of the second wind turbine in such a way that the rotational speed of the first wind turbine differs from the rotational speed of the second wind turbine by at least a predefined differential rotational speed.