Damping oscillations using active filters

An arrangement for controlling a converter of a power generation system, the converter being connected to a connection point to a utility grid, the arrangement comprising:

• a measurement section adapted to provide measurement values indicative of values of current and voltage at the connection point;
• a main converter controller adapted to receive the measurement values and to generate a main converter control signal based on the measurement values;
• an active filter system adapted to receive the measurement values and to generate an active filter control signal based on the measurement values;
• and
• an addition element adapted to add the main converter control signal and the active filter control signal to obtain a sum signal and to supply the sum signal as a control signal to the converter;
• wherein the active filter system is adapted to dampen at least one low frequency harmonic oscillation generated by the converter and to allow impedance shaping of a converter impedance of the converter for at least one specific frequency.