Abstract:

The robust stability problem for neutral systems with time-varying delays and nonlinear perturbation is investigated. Based on the direct Lyapunov-Krasovskii functional approach and freeweighting matrix technology, neutral and discrete delay-dependent stability criteria for the system are formulated in terms of Linear Matrix Inequalities (LMIs). Unlike some existing methodologies, when dealing with the time derivative of Lyapunov-Krasovskii functional, the proposed approach involves neither model transformation nor dealing with the cross-term, and only introduces some freeweighing matrix for the correlation terms, in which the relationship between each terms is fully considered, and the less conservative robust stability criteria are proposed accordingly. At last, Matlab Toolbox LMI is used to perform some numerical simulations and the results demonstrate the effectiveness of the proposed stability criteria.

Key words: neutral system;Lyapunov-Krasovskii functional;robust stability;nonlinear perturbations;free-weighing matrix;linear matrix inequality