Characteristics of earth faults in power systems with a compensated or an unearthed neutral

This paper presents an analysis and comparison of earth fault characteristics in the medium voltage distribution networks (20 kV) with high impedance earthing. The results presented are based on the evaluation of 341 real case data recordings, obtained from substations of distribution networks with an unearthed or a compensated neutral. The networks were mainly of overhead construction, with a smaller share of underground cables.