Block diagram model for fundamental studies of a synchronous generator-static VAr compensator system

The unified block diagram model of a generator and flexible AC transmission system (FACTS) devices has been presented in the open literature, and used for fundamental investigation of damping torque contributions from FACTS devices into power systems. The model, however, does not always yield a realistic response since only the main field winding is assumed to exist in the generator model. The authors extend the generator model to incorporate the damper windings in the q- and d-axes. This allows a more realistic investigation of the dynamic interactions between the SVC and synchronous generator. The small-signal, dynamic performance of generator-SVC models, with a different number of generator windings on the d- and q-axes, is compared by means of the block diagram model presented in this paper. The analysis is carried out using frequency response methods