A simple method of tuning three-term controllers for integrating dead-time processes with inverse response

The use of the Pseudo-Derivative Feedback (PDF) structure in the control of integrating processes with both dead-time and inverse response (IPDT-IR) is investigated. A simple direct synthesis method for tuning the PDF controller is presented. The PDF control structure and the proposed tuning method ensure smooth closed-loop response to set-point changes, fast regulatory control and sufficient robustness against parametric uncertainty. Simulation results show that, in most cases, the proposed method is favorably compared to known PID controller tuning methods for IPDT-IR processes. Finally, a simulation-based application to the problem of controlling the level of a boiler steam drum is also reported.