Advanced Controllers Using Fuzzy Logic Controller ( FLC ) for Performance Improvement

Abstract

Sharma et. al., Advanced Controllers Using Fuzzy Logic Controller (FLC) for Performance Improvement  Abstract—Besides the advantages, there are some limitations of FLCs. The tuning of an FLC is a very difficult task. To make the tuning easy and efficient, there are several structures of fuzzy logic controllers are available. This paper considers new structures of fuzzy logic controllers. Two structures, self-tuning FLC (STFLC) and fuzzy supervised conventional PI controller (GSPI) are considered. In FLC control rules and scaling factors play very important role. In this paper, a self-tuning PI-like FLC (STFLC) is used for the tuning of output scaling factor. In FSPI, we tune the PI controller parameters with FLC. So, it adds the advantages of PID controller and FLC. The design of these controllers is discussed. These are implemented to control three non-linear example systems. The performance of FLC, STFLC and FSPI controller is compared with each other. It is found that STFLC and FSPI controller give better performance than the conventional PI controller or simple FLC. Index Terms— Fuzzy logic controller (FLC), Fuzzy supervised PI (FSPI) controller, Membership Function (MF), Self-tuning FLC (STFLC), Scaling factor (SF)