Robustness estimation of a system with consecutive compensator included according to the O. Smith scheme

The paper considers a closed-loop linear system with time delay. The system has a plant with pure time delay and consecutive compensator included according to the O. Smith scheme. The compensator gives the system desired properties of transient response and outputs pure time delay outside the closed loop. The article solves the assessment problem for the system robustness in relation to changes in the time delay of plant.