Modelling of doubly-fed induction generator for power system stability study

This paper discusses the modelling adequacy and control tuning of the doubly-fed induction generator (DFIG) for power system stability study. It is seen that the stator and rotor electrical dynamics should be considered when tuning the controllers. Once an appropriate set of control parameters are obtained the DFIG model is simplified whereby all electrical transients, both stator and rotor, are neglected. The reduced order model can then be used conveniently in large scale power system stability studies. A systematic control tuning procedure is proposed to address the stability issues particular to the DFIG. Root-loci analysis and time domain simulations of the non-linear system show that with the proposed tuning procedure, the closed-loop DFIG operation is stable over a wide range of operating conditions and machine parameters.