A Method of Fault Line Detection in ’ Distribution Systems Based on Wavelets

On the basis of farther research about characteristics of single-phase-to-ground fault transient information in neutral indirectly grounded systems and feature information which is abstracted from transient fault signals by wavelet, a novel fault line identifying method using signal singularity detection with the wavelet transform modulus maxims is presented in this paper. A new criterion is constituted by the distinct information embedded in wavelet transform modulus maxima of the transient electrical quantities in third scale in which the fault feature is most prominent and universal. Theoretical analysis and simulation results show that the proposed method can detect the fault line reliably and exactly and be suitable for various distribution systems with different neural grounding modes. Key Words-power distribution lines, network fault diagnosis, wavelet transforms