Improved stability criteria for uncertain neutral systems with time-varying delay

This paper is concerned with the robust stability of neutral systems with time-varying delays and norm-bounded uncertainties. Through constructing a Lyapunov-Krasovskii functional of more complete form, using slack matrices and the convex combination condition, the delay-dependent stability criteria are obtained in terms of linear matrix inequalities. Since the obtained criteria take account into the sizes of neutral delay, discrete delay and the derivative of discrete delay, they are less conservative than those produced by previous approaches. Numerical examples are given to illustrate both the improvement the proposed method provides over the existing ones and the relationship among the neutral delay, time-varying discrete delay and the derivative of discrete delay.