Exact robust tuning rules for integrating processes with dead time: a frequency response model matching approach

Abstract

Robust PI/PID controller tuning receives renewed interest from control communities. This paper presents a simple and intuitive robust tuning method for integrating processes with dead time via the frequency response model matching approach. Two-degree-of-freedom (2DoF) PI controller is utilized with controller parameters obtained by frequency response matching between the system with the controller and the desired regulatory/servo control reference model. Robust tuning rules are provided in terms of the process model parameters and the desired robustness evaluated by the maximum sensitivity. It is shown that the obtained tuning rules can achieve more exact achievement of the control system robustness than the existing methods, thus much better trade-off adjustment between performance and robustness can be expected. An illustrative example is given to show the effectiveness of the proposed tuning method.