Abstract: This disclosure is directed to a method for operating a wind farm having a plurality of wind turbines and to a control system for a wind farm. The wind farm is connected to an electrical grid. The wind turbines are operated to supply electrical power to the electrical grid in accordance with at least one setpoint value for a power related electrical variable. In the event that an available reactive power of the wind farm is smaller than a setpoint for a reactive power to be supplied by the wind farm, a required increase of reactive power is determined for each wind turbine of the wind farm.

Abstract: A method is provided for controlling a wind turbine that has a generator that is controlled via a converter in a boost operation, in which an electrical power that is fed into an electrical transmission network is increased via a generative deceleration of the generator. The method comprises using a control to determining a set point value for a generator torque depending on an actual value of a rotational speed. The determined set point value for the generator torque is applied to a generator via a limiter with a predefinable upper and lower limit. Determining the set point value for the generator torque in boost operation that leads to an increased fed-in electrical power in response to a boost signal; and limiting a temporal change of the set point value for the generator torque in a recovery operation in response to a recovery signal.

Abstract: A method for controlling a wind turbine comprising inputting an actual value of rotational speed and a rotational speed setpoint into a control and outputting a set point value for a generator torque from the control. Inputting the set point value for the generator torque into a limiter with a predefinable upper and lower limit and outputting a limited torque value that is fed into a converter control. Increasing the actual value of the fed-in electrical power by an additional amount of power in response to a boost signal, wherein the fed-in electrical power and the additional amount of power are combined into an aggregated power setpoint value. Determining the set point value for the generator torque from the aggregated power setpoint value and applying the set point value for the generator torque in the boost operation to the limiter both as the upper limit and as the lower limit.

Abstract: A method is provided for controlling a wind turbine that has a generator that is controlled via a converter in a boost operation, in which an electrical power that is fed into an electrical transmission network is increased via a generative deceleration of the generator. The method comprises using a control to determining a set point value for a generator torque depending on an actual value of a rotational speed. The determined set point value for the generator torque is applied to a generator via a limiter with a predefinable upper and lower limit. Determining the set point value for the generator torque in boost operation that leads to an increased fed-in electrical power in response to a boost signal; and limiting a temporal change of the set point value for the generator torque in a recovery operation in response to a recovery signal.

Abstract: A method for controlling a wind turbine comprising inputting an actual value of rotational speed and a rotational speed setpoint into a control and outputting a set point value for a generator torque from the control. Inputting the set point value for the generator torque into a limiter with a predefinable upper and lower limit and outputting a limited torque value that is fed into a converter control. Increasing the actual value of the fed-in electrical power by an additional amount of power in response to a boost signal, wherein the fed-in electrical power and the additional amount of power are combined into an aggregated power setpoint value. Determining the set point value for the generator torque from the aggregated power setpoint value and applying the set point value for the generator torque in the boost operation to the limiter both as the upper limit and as the lower limit.

Abstract: A method is for damping electromechanical oscillations on a power system by injecting reactive power generated by one or more wind turbines. A reactive power controller is adapted to determine a reference reactive power value depending on an actual system voltage. The method includes: measuring oscillation data, filtering the measured oscillation data to remove a steady state offset, providing a gain and a phase shift to the filtered data to compensate a gain in the reference reactive power value caused by the reactive power controller in response to electromechanical oscillations, and a delay in the reference reactive power value caused by the reactive power controller, and to generate corrected oscillation data, and determining a reactive power setpoint to be injected into the power system by the wind turbines based on the reference reactive power value and the corrected oscillation data, wherein the damping is continuously applied to the oscillation data.