An accurate fault location technique for distribution lines with tapped loads using wavelet transform

This paper investigates the application of wavelet transform as an accurate fault location technique for power distribution lines with tapped loads. When a fault occurs, a transient wave travels from the fault point to substation busbars and load terminals. The time taken for the fault generated transient wave to arrive at busbars or load terminals depends on the distance traveled and the velocity of the travelling wave. In this paper, fault transient detectors (FTDs) based on digital wavelet transform (DWT) are installed at substation busbars and load terminals to capture the time taken for the transient to arrive and be synchronized with a Global Positioning System (GPS) clock. From the recorded time and the topological structure of the network, an accurate fault location is deduced. The fault location technique is validated by EMTP/ATP on an 11 kV distribution line with 7 tapped loads