Primary load-frequency control from pitch-controlled wind turbines

In this paper, an operating strategy is suggested for the participation of variable speed, variable pitch wind generators (VSVPWG) in primary load-frequency regulation through pitch-control. The proposed strategy is mathematically precise and neither direct wind measurement as a control input, nor any linearization of the system are required. The above suggested are independent of the specific type of the electric generator connected to the turbine and the only requirement is the expansion of the look-up tables of the aerodynamic characteristics of the rotor. The operating strategy is applied to a VSVPWG model developed in MATLAB-Simulink and connected to both a doubly-fed induction generator (DFIG) and a full-power converter synchronous generator (FPCSG). Indicative simulation results are shown, the effectiveness of the proposed control versus wind and set-point of power variations is validated, tuning issues are addressed and lastly a comparison is presented between the aforementioned technique and the method of over-speeding previously developed and published in the specific field of research.