Modeling and simulation of a DFIG-based wind-power system for stability analysis

This paper deals with the modeling and simulation of a double-fed induction generator (DFIG) based wind-power unit which is connected to the grid through a series-compensated transmission line. A detailed model of a DFIG in the rotor flux reference frame, along with its controllers, is developed in this paper. This paper proposes a comprehensive set of differential equations for grid connection of DFIGs that takes into account the dynamics of the grid side line filter and transmission line. Time domain simulations are performed in Matlab/Simulink. Based on the model and simulation results, system stability is investigated for different series compensation levels. Also, the effect of grid stiffness on the system stability is studied. Potential of sub-synchronous resonance (SSR) oscillations is investigated and the proper system and controller parameters which make the system stable and mitigate hazards due to SSR are identified.