Pires, V. FernãoFortunato, Carlos2013-05-282013-05-282012http://hdl.handle.net/10400.26/4296This paper presents a new approach to a numerical current differential protection for the transmission lines. The current differential algorithm uses a pattern recognition method. First the acquired current signals are transformed into “dqo” components by applying the Park transformation. The transformed currents will originate typical patterns according the fault type. Using a pattern recognition algorithm the different faulty conditions are identified. Several tests under different fault conditions were performed. The obtained results allow verifying the effectiveness of the proposed approach.engCurrent differential protectionPattern recognitionLine protectionDigital relayconference object