Design of a Fuzzy PI Controller for Power System Applications

A new adaptive fuzzy excitation controller for synchronous generators is proposed using fuzzy set theory. In the proposed linguistic fuzzy controller, generator speed deviation (Δω) and acceleration (Δω) are taken as controller inputs. A simple rule base consisting of a minimum number of rules is used for designing the fuzzy controller. A predictive routine is used for generating an adaptive compensating control when the system operating conditions or parameters change. To demonstrate the effectiveness of the fuzzy excitation controller, digital simulations of a power system subject to large and small signal disturbances over a wide range of operating conditions are performed. It is found that the adaptive fuzzy excitation controller produces significant damping in comparison to the conventional controller using a fixed gain structure.