Ismail Niazy - Department of Electrical Engineering, Ferdowsi University of Mashhad, Iran
Javad Sadeh - Department of Electrical Engineering, Ferdowsi University of Mashhad, Iran
Ebrahim Niazy - Department of Electrical Engineering, Ferdowsi University of Mashhad, Iran

This paper presents a new single ended fault location method for underground cable combined with overhead line that uses fault clearing transients instead of fault-generated transients without utilizing line parameters. Applying wavelet transform on voltage samples taken from the sending end of the cable, first, second and third inceptions of traveling waves to the fault locator are detected and faulty section is determined. Then, exact location of fault is calculated. Single-ended algorithm, does not need to the communication system and GPS. Accuracy of algorithm is not affected by aging, climate and temperature variations, which change the wave speed. Fault resistance, fault inception angle and fault distance does not affect accuracy of algorithm. Extensive simulations carried out usingSimPowerSystem toolbox of MATLAB software, confirm the capabilities and high accuracy of the proposed method to find the location of fault under different system and fault conditions.

Fault location, fault clearing transients, combined lines, wavelet transform, wave speed