In this paper, A dynamic modeling and power control scheme for doubly-fed induction generator (DFIG) for variable speed wind power generation is proposed. A detail dynamic model of a DFIG-based, wind turbine and grid-connected system is presented in the d-q-synchronous reference frame. A robust controller based on sliding mode controller (SMC) is applied in order to control the power flowing between the stator of the DFIG and the power network. To improve the controller performance in steady state the integral sliding mode controller (ISMC) is used. Also, ISMC is used to achieve the controller robustness. Its respective performance is compared in terms of power reference tracking, sensitivity to perturbations in sub-synchronous and super-synchronous modes and robustness against machine parameters variations. Moreover, the proposed ISMC performance is compared with the conventional proportional-integral control. |
