Robust Output Feedback Control via Pole Constraints for Sampled-Data System with Long Time-Delay

With the rapid development of computer and communication technology, sampled-data system has received a great deal of attention. Therefore, the problem of robust output feedback control via pole constraints for sampled-data system with long time-delay is considered in this paper. Firstly, continuous control plant of sampled-data system with long time-delay is transformed into an uncertain discrete-time system model. Moreover, output feedback controller is designed such that the closed poles are located within a prescribed circular region, and H norm of the closed-loop transfer function is strictly less than a given positive scalar for all admissible uncertainties. By introducing Lyapunov stability theory and state augmented approach, the problem is solved. At the same time, the existence condition and design approach of robust controller are presented in terms of linear matrix inequalities (LMIs). Under the assumption that time-delay is longer than sampling period. Finally, simulation examples are employed to illustrate our robust output feedback design and to verify the effectiveness and validity over other existing results.