Fault prelocalization of underground single-phase cables: Modeling and simulation

This paper proposes a tool of assistance to prelocate insulation faults affecting electrical single-phase cables by using measurements of voltage and current available in source substation. An equivalent network modeling faults to the ground is analyzed by employing the distributed parameters approach. The per-unit length values of these parameters are calculated according to the geometrical data of the cable. The specificity of this tool is the introduction of a resistance to model sheath-ground insulation what allows studying various types of short-circuits to the ground (frank and resistive). Scenarios of fault are applied to the underground cable 150 kV, connecting high voltage (HTB) sub-stations of Tyna–Taparoura–Sidimansour in Sfax city of Tunisia. A study of validation is approved by the software Simulink–SimPowerSystems of Matlab.

► We develop an assistance tool to prelocate single-phase underground cables faults.
► We calculate the per-unit length values according to the physical laws.
► Fault analysis considers only electrical measurements available in one substation.
► Fault equation is described by the sheath behavior at fault point.
► The error estimated on the fault distance does not exceed 3%.