A new robust PID controller design methodology for systems with unstable zero

The proposed new method is applicable for control of linear stable single-input-single-output non-minimum phase systems even with unknown mathematical model and unstructured uncertainties. The control objective is to provide required nominal maximum overshoot and settling time of the controlled variable y(t). The proposed new controller design approach guarantees fulfillment of these performance measures specified by the designer for processes with unstable zero. The developed algorithm has been extended to guarantee robustness of the PID controller design for uncertain processes modelled by unstructured uncertainties, and verified on a vast batch of benchmark examples.