Robust stability for uncertain neutral systems with mixed delays
QIAN Wei1,2, SHEN Guo-jiang1, SUN You-xian1
(1. State Key Laboratory of Industrial Control Technology, Zhejiang University, Hangzhou 310027, China;
2. School of Electrical Engineering and Automation, Henan Polytechnic University, Jiaozuo 454000, China)
The robust stability for neutral systems with mixed delays and uncertainties was investigated. The uncertainties under consideration were nonlinear perturbations and norm-bounded uncertainties, respectively. A novel Lyapunov-Krasovskii functional was constructed and its positive definiteness was proved by using integral inequality, whichrelaxed the constraint on some functional parameters. The neutral-delay-dependent and discrete-delay-dependent stability criteria for two different forms of uncertainty were derived by using Lyapunov method in terms of linear matrix inequalities. Then the conservatism caused by neutral-delay-independence was relaxed. The numerical examples weregiven to illustrate the effectiveness of the method and the improvement over some existing methods.
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