Simple Tuning of Discrete PI and PID Controllers

The paper investigates the effectiveness of a simple procedure for tuning discrete PI and PID controllers applied to processes subject to set point changes and load disturbances. Previous work is extended to obtain closed-loop stability properties and a complete set of graphical tuning relationships to minimise the ITAE performance index when the process under control can be represented adequately by a single time constant and time delay. In addition, the simple tuning procedure is shown to exhibit satisfactory performance when applied to the control of a process represented by an eighth order transfer function.