Localization method for the resistive earth faults in compensated network based on simultaneous earth faults evaluation

This paper is focused on locating earth fault by means of short-term additional earthing of unaffected (healthy) phase and the determination of fault distance based on the distance protection principle. The functionality of above mentioned method was verified during experiments, which were performed in the actual distribution network. The results of the experiments showed that the method of additional earthing of healthy phase is very effective for localization of low resistance and arc earth faults. The line impedance to fault was correctly evaluated by distance protection in the affected feeder during experiments, which in low resistance faults were simulated. In the case of resistive faults and that´s already the order of tens of ohms, it is necessary to determine the impedance to the fault location using a different algorithm, which is based on the evaluation of currents and voltage during simultaneous earth faults. Method for evaluation of the line impedance between two simultaneous earth faults in network, which is suitable for resistive earth faults location is proposed in this paper.