Observer-based H-infinite Control for Industrial Ethernet Control Systems with Time Delay and Packet Dropout

Ethernet is finding increasing application in industrial environments as a replacement for conventional field bus systems. The key technical obstacle of Ethernet for industrial application is that its non-deterministic behavior makes it inadequate for real-time application. In order to solve these problems, this paper investigates the observer-based H∞ control problem of networked control systems with time delay and packet dropout. The random packet loss is modeled as a Bernoulli distributed white sequence with a known conditional probability distribution. In the presence of random packet dropout, sufficient conditions for the existence of an observer-based feedback controller are derived for the NCSs ´ asymptotic stability based on robust stability techniques, under which the system is exponential stability with a desired H-infinity disturbance attenuation level. The designed observer-based H∞ controller is obtained by solving a set of linear matrix inequalities. The result illustrate that the effectiveness of the proposed control design and the satisfactory performance of the system.