Automatic Generation Control of a Wind Farm with Variable Speed Wind Turbines

Wind farms are considered as negative loads from the point of view of the utility manager. Modem variable speed wind turbines offer the possibility for controlling active and reactive power separately. This paper presents a new integrated control system of a wind farm according to the utility manager requirements. This control system is based on two control levels: a supervisory system controls active and reactive power of the whole wind farm by sending out set points to all wind turbines, and a machine control system ensures that set points at the wind turbine level are reached. The system has been validated by numerical simulation using data from a wind farm with 37 variable speed wind turbine sited in northern Spain. Automatic generation control of these characteristics promises an improved performance of the system and a better grid integration of the wind energy without significant extra costs.