Decentralized observer based tracking control of uncertain interconnected systems

The focus of this paper is on the design of a decentralized state observer based tracking control for a class of interconnected systems. Moreover, this control approach is improved to result in perturbed systems through the use of a modified H
_∞
criterion. The decentralized control approach is proposed to ensure the H
_∞
model reference tracking control and to reconstruct the non measurable state variables of each subsystem. Sufficient conditions for the designed problem are formulated in terms of linear matrix inequalities (LMIs), which can be efficiently solved by the LMI optimization techniques to compute the observation and the control gain matrices of the interconnected system. The efficiency of the proposed control approach is highlighted by numerical simulation on a power system with three interconnected machines.