Design of interval observer for continuous linear large-scale systems with disturbance attenuation

A design method of interval observers for linear continuous large-scale systems is proposed in this paper. The considered systems are subject to disturbances that are assumed to be unknown but bounded. With the aid of continuous Lyapunov functions, the error system of the original system and the interval observer system is asymptotically stable and its state is nonnegative, allowing sufficient conditions for interval observers of large-scale systems to be obtained and expressed as linear matrix inequalities. Furthermore, the L stability theory is used in the design of interval observers for large-scale systems to increase the accuracy of interval estimation. Interval observers design methods are proposed for large-scale systems with L₁/L₂ gain performance. Two numerical examples are provided to demonstrate our findings.