Research on eigenparameters and detection methods for single‐phase‐to‐ground faults in non‐effectively grounded distribution systems

Non-effectively grounded power distribution systems (NGDS) are widely used in China and other countries. However, over a long time, single-phase-to-ground faults (SGF) have been misjudged or omitted by the monitoring system, threatening security of supply system human safety. Based on reason analysis for SGFs NGDS, concept NGDS fault eigenparameters to correctly reflect characteristics method SGF detection based proposed. Then, mechanism phase voltage current resistive elements is revealed. The variation typical parameters changing with scale (parameter) transition resistance, such as residual Zero-sequence (iA-iO), analysed. certain specific scales/parameters also proposed, which can under different resistances.