Studies on PI/PID controllers in the proportional integral plane via different performance indices

The PI/PID parameters for first order plus time delay (FOPTD) and second order plus time delay (SOPTD) systems have been obtained by minimizing the cost function of four different time domain performance indices. The stabilizing parameters region and location of PI/PID values have been portrayed in the proportional-integral plane of the controller to study the relative stability. We have shown via simulation that PI/PID settings obtained by minimizing the cost function obtained by the combination of above four performance indices, give an overall better closed loop performance measures.