Electromechanical extensions of circuit-based Lyapunov functions with applications to detailed power system models

This paper presents a formulation of differential equations for a class of nonlinear electromechanical systems. The resulting form is reminiscent of Hamiltonian structure and leads naturally to a candidate Lyapunov function. The proposed approach is illustrated with, and a "natural" candidate Lyapunov function identified for a two machine power system with detailed synchronous machine models. Such an approach is particularly useful as limitations of sinusoidal quasisteady state approximation for transient analysis of power systems become pronounced