Reliable H∞ dynamic output feedback synthesis for linear systems

This paper considers the problem of reliable H_infin control against actuator failures for linear continuous-time systems. The model including actuator partial failures and actuator lock-in-place failures is presented, and the faults of being locked in place are accurately described as zero-frequency disturbances and their attenuation performances are described by using small gain conditions based on finite frequency approach. Then a two-step LMI-based algorithm is developed for designing reliable H_infin dynamic output feedback controllers. The resulting designs guarantee the stability and disturbance/fault attenuation performances of the closed-loop systems, not only when all control components are operational, but also in case of some actuator failures. Finally, a numerical example is given to illustrate the advantage of the proposed design method in comparison with the entire frequency approach by using bounded real lemma.