Single-phase faults on compensated neutral medium voltage networks

The authors reiterate the reasons that justified a two-stage evolution of the neutral earthing of the French medium voltage networks. In the context of overall coherence, EDF are aiming to guarantee: coordination of insulation for our MV and LV networks and for LV customers; safety of people and equipment (taking into account touch voltage, step voltage, coupling phenomena); a better quality of supply; and conformity of their practices to standards. Network experiments carried out over the last four years have confirmed their theories and validated expected solutions. Specifications for new devices have been established, based on functional requirements of the distributor