Control method for variable speed wind turbines to support temporary primary frequency control

This paper develops a control method for variable speed wind turbines (VSWTs) to support temporary primary frequency control of power system. The control method contains two parts: (1) up-regulate support control when a frequency drop event occurs; (2) down-regulate support control when a frequency rise event occurs. The up-regulate support is achieved by adaptively utilizing the wind energy curtailed by the pitch control and the kinetic energy stored in the rotating mass of the turbine blades. The down-regulate support is achieved by the pitch control. Furthermore, the up- and down-regulate capabilities are quantified under different wind speeds. Finally, the whole control method is verified in a test power system established in MATLAB/Simulink, which contains a wind farm of 180 VSWTs.