Synchrophasor measurement-based fault location technique for multi-terminal multi-section non-homogeneous transmission lines

This study presents a fault-location technique for multi-terminal multi-section non-homogeneous transmission lines which combine overhead lines with underground power cables, by using voltage and current synchrophasors obtained from phasor measurement units. First, a faulty line branch is selected to narrow down the suspected faulty area. Then, the faulty section and the exact fault location can be identified by calculating the normalised fault distance for each section on the selected faulty branch. Computational burden of the proposed analytical scheme is very low because it avoids iterative computations. Promising simulation results show that the proposed fault location technique can accurately locate the fault regardless of the fault type, fault resistance, fault location, pre-fault loading and line parameters inaccuracies.