A two-time scale framework for stability analysis of electrical power system

This paper discusses the foundations and proposes a general framework to decompose the stability analysis of electrical power systems in time-scales. Assuming that the electrical power system model possesses two-time-scale features, the stability analysis of the original two-time-scale power system model is decomposed into the stability analysis of two simpler models: the fast and slow subsystems. Conditions to guarantee that stability of these simpler subsystems implies stability of the complete model are given. The general framework is suitable for stability analysis of power systems in a time frame that can range from a few seconds, which is typically the scenario of transient stability analysis, to a few minutes, which is typical of mid-term stability analysis, in which voltage stability problems are commonly encountered.