Investigating the positive effects of packet dropouts on network-based H∞H∞ control for a class of linear systems

This paper investigates the positive effects of packet dropouts on network-based H∞H∞ control for a linear system that cannot be stabilized by a non-delayed static output feedback controller, but can be stabilized by a delayed static output feedback controller. By intentionally inserting a lossy network between the system and the controller, and embedding a logical packet-selecting algorithm that produces some packet dropouts in the actuator module, the networked control system is modeled as a system with an interval time-delay, which is stable with some nonzero   time-varying delay, but is unstable without a time-delay. By constructing a complete Lyapunov–Krasovskii functional and discretizing both the lower bound and the upper bound of the interval delay, some new delay-dependent criteria for H∞H∞ performance and controller design are derived in terms of linear matrix inequalities. It is shown through an example that (i) proper packet dropouts can produce a stable control effect; (ii) utilizing the discretization of the lower delay bound can reduce the conservatism of the H∞H∞ performance criterion; and (iii) the proposed design result is effective in achieving satisfactory H∞H∞ control performance.