A SIMPLE AUTOTUNING METHOD USING PROPORTIONAL CONTROLLER

In this study, we propose a simple autotuning method using proportiona l controller. A second order plus time delay model is used in the on-l ine closed-loop identification and tuning of PID controllers. This mod el can approximate processes over a wider frequency region than a firs t order plus time delay model, which is often employed in model-based autotuning methods. Moreover, since the identification method requires only a simple least squares method to estimate the model parameters, no complex numerical techniques such as root-finding or optimization m ethods are employed, thus making it practical, unlike many other previ ous identification methods. Simulation studies demonstrate that the pr oposed method shows satisfactory identification and better control per formances than other previous methods for various processes. In the id entification step, it shows insensitivity to measurement noise and inp ut disturbances. The results of the experimental study confirm its val idity and capability and show its promise in industrial situations.