Method of damping electromechanical oscillations on a power system by injecting reactive power generated by one or more wind energy turbines (WTG 1-5), wherein a reactive power controller is adapted to determine a reference reactive power value (Q ref ) depending on an actual system voltage (U meas ) , the method comprising: - measuring oscillation data associated with the power system , - filtering the measured oscillation data to remove a steady state offset, thereby obtaining filtered oscillation data, - determining a frequency value and an amplitude value from the filtered oscillation data , and - triggering a switchable power oscillation damping according to at least one criteria of the following: o the frequency value determined from the filtered oscillation data falling within a predetermined frequency interval, and o the amplitude value determined from the filtered oscillation data exceeding a predetermined threshold value, - wherein the switchable power oscillation damping is achieved by compensating a gain and a delay caused by the reactive power controller to the reference reactive power value (Q ref ), thereby obtaining a corrected reference reactive power value - wherein, additionally to the above switchable power oscillation damping, a continuous power oscillation damping is provided, which comprises the steps of correcting a gain and a shift in either the corrected reference reactive power value in case the switchable power oscillation damping is triggered, or in the reference reactive power value (Q ref ) in case the switchable power oscillation damping is not triggered , thereby compensating a gain and a delay caused by the reactive power controller , - outputting a reactive power setpoint (O set,WTGs ) to at least one of the plurality of wind energy turbines (WTG 1-5) based on at least one of: the reference reactive power value (Q ref ) and the corrected reference reactive power value. - measuring oscillation data associated with the power system , - filtering the measured oscillation data to remove a steady state offset, thereby obtaining filtered oscillation data, - determining a frequency value and an amplitude value from the filtered oscillation data , and - triggering a switchable power oscillation damping according to at least one criteria of the following: o the frequency value determined from the filtered oscillation data falling within a predetermined frequency interval, and o the amplitude value determined from the filtered oscillation data exceeding a predetermined threshold value, o the frequency value determined from the filtered oscillation data falling within a predetermined frequency interval, and o the amplitude value determined from the filtered oscillation data exceeding a predetermined threshold value, - wherein the switchable power oscillation damping is achieved by compensating a gain and a delay caused by the reactive power controller to the reference reactive power value (Q ref ), thereby obtaining a corrected reference reactive power value - wherein, additionally to the above switchable power oscillation damping, a continuous power oscillation damping is provided, which comprises the steps of correcting a gain and a shift in either the corrected reference reactive power value in case the switchable power oscillation damping is triggered, or in the reference reactive power value (Q ref ) in case the switchable power oscillation damping is not triggered , thereby compensating a gain and a delay caused by the reactive power controller , - outputting a reactive power setpoint (O set,WTGs ) to at least one of the plurality of wind energy turbines (WTG 1-5) based on at least one of: the reference reactive power value (Q ref ) and the corrected reference reactive power value. <EOS>