Underground cable fault detection and identification via fourier analysis

In this paper, the analysis of underground power cables is performed using Fourier analysis with the objective of detecting fault and average life of the cable. Three types of cables are used in this experiment; a normal cable, a shorted cable, and a cable with holes. The impedance in each case is computed and Fourier transformation is applied so that the resulting impedance magnitude and impedance phase can be examined in the frequency domain. Various windowing techniques are applied to the experimental data to eliminate any interference. Fourier analysis is then applied to the impedance data calculated from both sending end voltage and differential voltage. This analysis reveals differences in the frequency response of the three different types of a cable and eventually can be used as a measure for fault detection. Preliminary results reveal the differences in the frequency response. Accordingly, Fourier type methods can be effectively used as low cost and viable solutions to identify and detect faults in underground cables.