Active Power Control Strategies of DFIG Wind Turbines

This paper is devoted to the active power control of DFIG wind turbines. An adaptation of the usual power set point control has been proposed in order to improve the transient behavior for high wind speeds. Several strategies for the active power control are studied. In the high wind speed range, the pitch control seems the most relevant to release a power margin while, in the low wind speed range, the increase of the rotation speed is more convenient. The power margin set point variation rate has to be limited in order to avoid torsion oscillations of the shaft. Nevertheless, the reaction speed of the wind turbine lies in the time frame of seconds, so that the participation to the primary frequency control is feasible.