A system and method are provided for controlling a wind turbine. Accordingly, a controller of the wind turbine detects a transient grid event and generates a torque command via a drive-train-damper control module. The torque command is configured to establish a default damping level of a torsional vibration resulting from the transient grid event. The controller also determines at least one oscillation parameter relating to the torsional vibration and determines a target generator torque level based thereon. The target generator torque level corresponds to an increased level of damping the torsional vibration relative to the default damping level.

A wind turbine is provided. The wind turbine includes a transformer having a low-voltage side and a high-voltage side. The transformer is configured to step up a voltage of the low-voltage side of the transformer to a voltage of an external grid. The wind turbine further includes an electrical power generating unit which is connected to the low-voltage side of the transformer and configured to feed an ac-power to the low-voltage side of the transformer. A charging device of the wind turbine is connected to the low-voltage side of the transformer and configured to charge the low-voltage side of the transformer when the generator does not feed ac-power to the low-voltage side of the transformer.

A system and method are provided for controlling a wind turbine. Accordingly, a controller of the wind turbine detects a transient grid event and generates a torque command via a drive-train-damper control module. The torque command is configured to establish a default damping level of a torsional vibration resulting from the transient grid event. The controller also determines at least one oscillation parameter relating to the torsional vibration and determines a target generator torque level based thereon. The target generator torque level corresponds to an increased level of damping the torsional vibration relative to the default damping level.

A solution to optimally manage those requirements ensuring on the one hand, that the requirements set by the grid operators are appropriately and accurately accomplished at a point of interconnection (POI) and on the other hand, preventing the wind turbines from over fulfilling the requirements, for example, by remaining connected at voltages levels higher or lower than the ones required which, although possible, may cause higher loads and currents in the wind turbines than needed to fulfill the requirements.

A wind turbine system comprising a nacelle mounted on a tower, a rotor having a plurality of blades and a boundary layer control system configured to control airflow through blade surface openings in each of the blades. The wind turbine system includes a control system configured to: monitor an operational speed parameter of the wind turbine, and activate the boundary layer control system if it is determined that the operational speed parameter exceeds a predetermined speed parameter threshold; monitor tower motion and to activate the boundary layer control system based on a determination of excessive tower motion; monitor for a wind turbine shutdown condition, activate the boundary layer control system if it is determined that the shutdown condition has been identified; monitor the aerodynamic loads on the blades, and activate the boundary layer control system based on a determination of excessive blade loads.

A method, control arrangement, and wind power plant (WPP) comprising a plurality of wind turbine generators (WTGs) are disclosed. The method includes operating, responsive to a received power demand corresponding to the WPP, a boost group of one or more WTGs of the plurality of WTGs to begin producing a boosted power output, wherein the boosted power output of each of the one or more WTGs of the boost group is regulated independent of the power demand. The method further includes determining, based on a measured amount of boosted power production, power production set points for a regulation group of one or more different WTGs of the plurality of WTGs to thereby meet the power demand.

A solution to optimally manage those requirements ensuring on the one hand, that the requirements set by the grid operators are appropriately and accurately accomplished at a point of interconnection (POI) and on the other hand, preventing the wind turbines from over fulfilling the requirements, for example, by remaining connected at voltages levels higher or lower than the ones required which, although possible, may cause higher loads and currents in the wind turbines than needed to fulfill the requirements.

A wind turbine system comprising a nacelle mounted on a tower, a rotor having a plurality of blades and a boundary layer control system configured to control airflow through blade surface openings in each of the blades. The wind turbine system includes a control system configured to: monitor an operational speed parameter of the wind turbine, and activate the boundary layer control system if it is determined that the operational speed parameter exceeds a predetermined speed parameter threshold; monitor tower motion and to activate the boundary layer control system based on a determination of excessive tower motion; monitor for a wind turbine shutdown condition, activate the boundary layer control system if it is determined that the shutdown condition has been identified; monitor the aerodynamic loads on the blades, and activate the boundary layer control system based on a determination of excessive blade loads.

A method for controlling a renewable energy generator, the renewable energy generator being connected to a Point of Interconnection of an external power grid by a connecting network, wherein the connecting network has an associated impedance level. The method comprising: monitoring at least one parameter of the connecting network and the voltage level at the Point of Interconnection; generating, during normal operating conditions, at least one current injection profile based upon the at least one measured parameter and a predetermined injection profile; and operating the renewable energy generator, during a grid fault, to output current according to the at least one current injection profile, so as to achieve a current set point at the Point of Interconnection.

Provided are a control method and system for enhancing an endurance capability to an abnormal voltage of a wind turbine generator system. The control method, includes; providing a doubly-fed wind turbine generator system connected to a power grid; detecting a voltage of the power grid, and determining whether the voltage of the power grid has a fault; when the voltage of the power grid has a fault, detecting a voltage of the DC buses, and determining whether the voltage of the DC buses exceeds a limit value; when the voltage of the DC buses exceeds the limit value, performing integrated system coordination control according to an abnormal operating condition mode; and when the voltage of the power grid returns to a normal range, performing integrated system coordination control according to a normal operating condition mode.