Fuzzy power system stabilizer including a fuzzy PI controller

The use of power system stabilizers (PSS) has become very common in operation of large electric power systems since the early seventies. However, it was very difficult to design a stabilizer that could present good performance in all operating points of electric power systems. Fuzzy logic control has been suggested as a possible solution to overcome this problem, by using linguistic information and avoiding a complex system mathematical model. This work proposes a fuzzy power system stabilizer (FPSS) combined with a fuzzy PI controller. Simulations show good results for several machine operating points, demonstrating better results than a conventional PSS