Shi Zhongke,Dai Guanzhong
(Department of Automatic Control,Northwestern PolytechnicalˇˇUniversity,Xi'an ˇˇ710072,China)
Abstract:A new robust stability analysis method for time-delay system is presented. Through equivalent transformation of polynomial matrix inequality, the solvable condition for the inequality is obtained. Based on this condition, the robust inequality criterion for time-delay system is simplified and a numerically high efficient algorithm is developed. When systems are with multiple time delays, the equivalent inequity for the determination of robust stability of systems is provided, and the design method of robust feedback controller is introduced simultaneously. Comparison with other robust analysis methods of time-delay system shows that the new approach is more convenient to implement for both the robust stability analysis and the feedback control design. When all the poles hoped are considered as negative real, only one single value decomposition is needed, and other computational complexity of the new robust controller design is just as the one of ordinary pole assignments. The new algorithm of controller design is suitable to both single and multiple time delay systems.
Keywords:robust stability;time-delay system;flight control;feedback controller design