[IEEE 2017 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM) & 2017 Intl Aegean Conference on Electrical Machines and Power Electronics (ACEMP) - Brasov, Romania (2017.5.25-2017.5.27)] 2017 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM) & 2017 Intl Aegean Conference on Electrical Machines and Power Electronics (ACEMP) - Issues of selective detection and elimination of earth faults in MV networks with the neutral treated by Petersen coil