A power sensitivity model including generator damper windings for electromechanical oscillations studies

This paper describes the derivation of a power sensitivity model including generator damper windings for power systems electromechanical oscillations studies, subjected to small disturbances on operation conditions. The need of an infinite bus representation is avoided with the linearized nodal power balance approach. This permits the model to be easily extended to multimachine systems. Due to its structure-preserving characteristic, loads modeled as nonlinear functions of voltage and frequency and all control loops can be easily taken into account. First, the model is derived for a single generator connected to an infinite bus. Then, its performance is compared with the modified Heffron-Phillips model proposed by Saidy and Hughes. Finally, the results of a two area system are presented in order to show the effect of the damper windings on the tie-line flow.