Provided is a method of generating a converter control signal for a generator side converter portion, in particular of a wind turbine, being coupled to a generator, in particular a permanent magnet synchronous machine, the method including: deriving at least one harmonic torque reference, in particular based on a harmonic torque demand and/or a torque indicating feedback signal; deriving at least one harmonic flux reference, in particular based on a harmonic stator voltage demand and/or a stator voltage indicating feedback signal; adding all of the at least one harmonic torque reference to a fundamental torque reference and subtracting an estimated generator torque to derive a torque error; adding all of the at least one harmonic flux reference to a fundamental flux reference and subtracting an estimated generator flux to derive a flux error; and deriving the converter control signal based on the torque error and the flux error.