This article presents a new algorithm based on fuzzy logic for differential protection of power transformers. The fuzzy approach used in this work is able to detect and discriminate between an internal fault and other operating conditions, such as energization, sympathetic inrush and overexcitation. The electrical power system, including the power transformer studied, was modeled using the ATP (Alternative Transients Program) software to obtain data of operational conditions and fault situations in order to test the developed algorithm. Concerning the validation process, the results were compared to a commercial relay, showing the advantages of the proposed method.
Electrical power system; Differential protection; Power transformer; Sympathetic inrush; Fuzzy logic; ATP
