SPECIAL FEATURE PID TUNING Optimal PID tuning using direct search algorithms

Methods for tuning PID controllers so that the closed-loop response closely matches that of a reference model are described. These approaches are based on direct search optimisation using an identified model and can be applied to a wide variety of industrial processes, including those with high-order dynamics. Results from the application to controller tuning for two distinct industrial systems are presented which demonstrate both the power and the limitations of the technique.