AUTOMATIC TUNING OF OPTIMUM PID CONTROLLERS

The paper first briefly reviews the analytical procedures for obtainin g optimum PID controller settings for minimisation of time weighted in tegral performance criteria. The approach is then used to obtain formu lae for setting the controller parameters for a first-order plus dead time plant model which is a common approximation used in the process i ndustries. These results are further extended to obtain two procedures , which can be used with the relay autotuning approach, to find the re quired controller parameters for optimisation of the integral of time error squared criterion. Good results have been obtained when these cr iteria are used with other plant models.