Electrical authorities require fast and accurate fault locators to protect tha quality of supply and reduce outage times. Spread spectrum techniques perform well in high
noise environments such as power lines and their use in radar ranging is well known. Existing power line carrier (PLC) equipment may be used to transmit a direct sequence signal down a faulted EHV line. The fault position may then be calculated from correlation analysis of the reflected waveforms. In this thesis the fault location process has been simulated on a digital computer taking into account the frequency variation of the PLC interface and line parameters over the spread spectrum bandwidth. The effect of waveform characteristics, fault location and resistance are examined for a 100 km double transposed line with a single phase to ground fault.