FOPID Controllers and Their Industrial Applications: A Survey of Recent Results 1 1This study is based upon works from COST Action CA15225, a network supported by COST (European Cooperation in Science and Technology).

Abstract

Abstract The interest towards using Fractional-order (FO) PID controllers in the industry is mainly fueled by the fact that these controllers have two additional “tuning knobs” that can be used to adjust the control law in a way that would benefit the control loop. However, there are certain points that are rarely addressed in literature, namely: (1) What are the particular advantages (in concrete numbers) of FOPID controllers versus conventional, integer-order (IO) PID controllers in the light of complexities arising in the implementation of the former? (2) For real-time implementation of FOPID controllers, approximations are used that are equivalent to high order linear controllers. What, then, is the benefit of using FOPID controllers? In the present paper, we attempt to address these issues by reviewing recent literature in the field and by providing relevant analysis and recommendations.