Development and implementation of new control schemes for process control applications using programmable logic controllers

Abstract

The modern industrial developments in process automation have been radically influenced by the application of advanced control methods implemented using Programmable Logic Controllers PLC The control of newlineprocess variables like level pressure and temperature is an important and newlineinteresting research problem in process applications The Proportional newlineIntegralDerivative PID controller is the conventional controller for linear newlineprocess with SingleInput and SingleOutput SISO Though the Distributed newlineControl Systems DCS have replaced the PLC in few of the process industries most industries still embrace the PLC for control purposes With increasing process dynamics such as delay time and nonlinearity newlineon the processes the PID controller itself turns out into a deficient newlinecontroller The controller gain values tuned from the steady state newlinecharacteristics are insufficient for the sudden changes in the process newlineparameters These factors also affect the disturbance rejection and servotracking newlinecapability of the PID controller The proposed research work focuses newlineto reestablish the robustness of the PID controller with simple and effective newlinegain adaptation mechanisms for PID through PLC newline newline