PSO Based H∞ PID Controller for a 2nd Order Time Delay System

The objective of the present work is to design an H infinity control theory based PID controller for a 2nd order time delay process. A novel approach Particle Swarm Optimization (PSO) has been employed to estimate the parameters of the PID controller. The infinity norm of the closed-loop plant transfer function with respect to disturbance has been minimized to satisfy H infinity control objective. The step response of the second order time- delay system has been studied with application of the designed controller for unity feedback. A parameter variation in the form of disturbance is applied in the processes and step response of the system has been observed for multiple cases. Simulation study reveals that the PSO based H infinity PID controller is effective and robust in the face of disturbance like parametric variation of the system.