This paper presents a heuristic method for fault location in transmission lines. It is established based on synchronized voltages sampling in line terminals using morphology approach. The proposed method uses only pre and during fault voltage phasors while traditional distance protection approaches require current transformers (CT) (with the issue of CT saturation and their errors), knowledge of line parameters and Thevenin impedance calculation. The proposed method is based on the voltage variations in the stationary reference frame (α-β). The changes of enclosed area of the voltage curve in the Clark coordinate due to fault is selected as the location criteria. Results indicates that the method is able to estimate fault point distances. However, the estimated fault point tolerates in a variable zone.
