A neural network trained to recognize patterns of transmission line faults is incorporated in a PC-based system that analyzes data files from substation digital fault recorders (DFRs). Recently, such a package, called DFR Assistant, was developed which can be installed locally in a substation. As soon as the DFR records a disturbance, data is automatically transferred to the PC and the fault analysis software determines if a fault has occurred and, if so, the type of fault. This conclusion is used to check if the relay operation is correct or not.
