Fuzzy PID controller design for load frequency control using gain scaling technique

Due to their simple structure and robust performance, proportional-integral-derivative (PID) controllers are the most commonly used controllers in industrial process control. The success of the PID controller depends on an appropriate choice of the PID gains. Tuning the PID gains are usually realized by experienced human experts. In this study, the authors first determine by experiments a set of tuning ranges of PID gains and after scaling these gains, a fuzzy based controller is designed for two areas power system as a supplementary controller. This is a two-level fuzzy PID controller.