Application of frequential properties of power systems to robustness analysis

This paper studies the application of certain frequency domain properties of a class of power systems to the robustness analysis. The small signal models of a significant class of power systems-namely, systems without resistive losses nor excitation control-was recently shown to meet passivity-like, convex conditions in the frequency domain. A classical benchmark is considered and it is shown that the presence of excitation control and resistive elements does not completely destroy the above-mentioned property, which remains valid in the frequency band associated to the electromechanical modes. The example includes a detailed robustness analysis showing the importance of the a priori knowledge of the frequential properties of these models in the frequency band of interest.