Delay Independent Stability Control for Commensurate Multiple Time-Delay Systems

Commensurate Multiple Time-Delay Systems (CMTDSs) are of considerable interest for many applications, ranging from process control to decision-making systems. A stable CMTDS can become unstable when a small delay is introduced and vice-versa. The letter proposes an innovative controller design procedure for CMTDSs, able to transform the system into a Delay Independent Stable System (DISS). A controller based on a single parameter is used to make the system DISS. The controller gain may be determined by adopting different strategies, either analytical or graphical. Several case studies are reported to illustrate and validate the approach.