“…Actually, in literature, a diversity of papers can be found concerning detection and identification of power quality disturbances by applying intelligent systems, such as Artificial Neural Networks (ANN) (Janik & Lobos, 2006;Oleskovicz et. al., 2009;Jayasree, Devaraj & Sukanesh, 2010) and Fuzzy Inference Systems (Zhu, Tso & Lo, 2004;Hooshmand & Enshaee, 2010;Meher & Pradhan, 2010;Behera, Dash & Biswal, 2010). However, only some papers use data pre-processing tools before the application of intelligent systems.…”