PSO-based PI-PD tuning for stable and unstable FOPTD processes

In this work, a new approach to design a proportional-integral proportional derivative (PI-PD) controller for stable and unstable system using Particle Swarm Optimization (PSO) technique is proposed. PSO is used to find the global optimum values of PI-PD parameters for stable and unstable first order plus time delay (FOPTD) processes which helps in easy implementation, stable convergence characteristic, better computational efficiency and fast tuning of process. In order to maintain estimating the performance of the proposed controller, a new time-domain performance criterion function was also defined i.e. Integral square error (ISE). The analysis and procedure are illustrated through simulation for open loop stable and unstable processes.