小电流接地系统单相接地暂态保护判据研究

分析了小电流接地系统单相接地故障时的电磁暂态过程，并重点分析了中性点经消弧线圈接地故障时的电容电流和电感电流在故障线路中的分布特点，基于这些分析提出了采用单相接地故障零序电流暂态首半波的幅值和相位特征量作为单相接地微机保护选线的判据，电力系统动态模拟试验论证了该判据的有效性。这为小电流接地系统实现快速、准确检测出故障线路提供了又一个重要依据。

A Study of the Protection of Single Phase Faulted Transient Current in Small Current Grounding Power Systems

The electromagnetic transient process was analyzed and studied for single phase grounding fault in small current grounding systems. The study focused on the distribution characteristics of the currents in the capacitor and inductor when the neutral point is connected to the ground by arc-reducing winding. Experiments have shown that the amplitude and phase angle of zero sequence transient current at both terminals of the line can be used as the criterion for the faulted line selection of single phase grounding fault by using the micro computer. This is the basis of the final design. The proposed method can provide a good basis for the quick detection of faulted lines in small current grounding power systems.