Analysis and design of a proportional plus derivative fuzzy logic controller

The objective of this paper is to present the analysis and design of a proportional plus derivative fuzzy logic controller (PDFLC) that combines the mathematical approach with the linguistic interpretation of the control system. The design of a fuzzy logic controller (FLC) generally involves manipulation of controller parameters based mainly on the designer's experience. A mathematical approach is needed to correlate FLC parameters with the system response but without obscuring the meaning of the actual physical action. In this paper, mathematical expression of PDFLC is developed and then used in time domain analysis to see the effect of controller parameter variation on the system response. The results from the analysis provide the basis for the design methodology developed. Finally, the step by step design procedure is presented and then demonstrated with a numerical example.