A new approach for fault type detection and identification in three-phase transmission lines is introduced. For this end, we have used the wavelet transform associated with a modal transformation. The wavelet coefficients, obtained by multiresolution decomposition, are then uncoupled. For short time analysis intervals, the energy levels in the transformed signals are extracted and compared with an appropriated threshold, determining then the fault type. A fault can be recognized in less than 2 ms after its occurrence. The Electromagnetic Transient Program (EMTP) and Alternative Transients Program (ATP) have been used for validating the obtained results.
Numeric Relays; Fault Identification; Pattern Recognition; Feature Extractor; Wavelet Transform
