Damping-dependent energy functions and impact on the stability region estimation

In this paper the stability region (domain of attraction) of damping-dependent energy functions for multi-machine power systems is analyzed and visualized for two-machine-infinite-system. It is shown that the damping-dependent energy functions give larger estimate of domain of attraction than conventional energy functions which don´t consider damping effect. Also the limitation of the previous structure-preserving damping-dependent energy functions for multi-machine systems in absolute angle form is addressed. In order to overcome the limitation an improved damping-dependent energy functions in the center of inertia (COI) form is presented as an extension of the previous work. Finally future work and possible applications are discussed.