Method, device and system for determining the fault position of a fault on a line of an electrical power supply network

A method determines a fault position on a line of a power supply network. Transient profiles of current and voltage values are measured at the line ends of the line and, by using the transient profiles, after the occurrence of a fault, a fault position is determined. To carry out fault location with high accuracy even in the case of a line having more than two line ends, transient profiles of a node current and a node voltage at a node point are determined by using the current and voltage values of a line end and a traveling wave model for the respective line section, and, for each line section, a two-sided fault position determination is carried out using the transient profile of the current and voltage values measured at its line end and, the node current and the node voltage and the traveling wave model for this line section.