New approach to intermittent earth fault detection with admittance criteria

摘要

Admittance based tripping criteria afford reliable earth fault protection of MV distribution feeders. Although highly effective for persistent earth fault detection, they often fail in the case of intermittent arcing faults when employed in the conventional protection schemes. In this paper the new approach to persistent and intermittent earth faults detection is proposed. The method is based on calculation of the cumulative intermittent arcing fault duration time. The validation based on data from numerical modeling of earth faults in EMTP as well as data recorded in real MV networks confirms the effectiveness of the approach.