Estimating the domain of attraction via union of continuous families of Lyapunov estimates

This paper proposes a new approach to estimate the domain of attraction of equilibrium points of polynomial systems. The idea consists of estimating the domain of attraction via the union of a continuous family of Lyapunov estimates rather than via one Lyapunov estimate only as done in existing methods. This family is obtained through a convex LMI optimization by deriving a stability condition which takes simultaneously into account all considered Lyapunov functions. Moreover, inner approximations of the union of this family via a set with simple shape are also derived.