DFIG Equivalence of a Wind Farm by Extended Kalman Filter based Parameters Estimation

The stability and reliability of the power system network are affected by the integration of large scale Wind Farms (WFs). Transient analysis of the power network using complex models of WFs is normally difficult. This paper, thus, proposes a Doubly-Fed Induction Generators (DFIGs) based equivalent model of large WF with its parameters estimated by the Extended Kalman Filter (EKF) approach. The proposed equivalent model of the wind farm is obtained by representing the rotor circuit of the DFIG as a constant current source. Hence, no measurements are required on the rotor side. The small-signal stability analysis proves the adequacy of the proposed model. The results are demonstrated for a practical model of the HornsRev1 WF integrated to the IEEE 39-bus system, and dynamic simulations of the aggregated model are compared to the complete detailed model. The simulation results show the efficiency, accuracy, and fast steady-state and dynamic analyses with the proposed aggregated model.