小电流接地选线在变电站出线保护装置的应用

Application of low current grounding line selection in substation outlet protection device

小电流接地系统发生单相接地故障后,由于变电站出线间隔接地选线功能的不足,导致系统不能及时进行接地选线和故障隔离,影响系统的安全可靠运行。针对此问题设计了一种基于故障暂态信号的小电流接地选线方案。实验表明该选线方案能够不受不稳定电弧和消弧线圈的影响,实现快速可靠的接地选线,同时选线方案对硬件配置要求较低,可配置在线路保护装置中,具有良好的实用价值。

After the single-phase-to-ground fault occured in the small current grounding system,due to the deficiency of the grounding line selection function of the substation outlet interval,the grounding line selection and fault isolation of the system can not be carried out in time,which affect the safe and reliable operation of the system.In view of this deficiency,a small current grounding line selection scheme was designed based on fault transient signal.Experiments show that the line selection scheme can realize fast and reliable grounding line selection without the influence of unstable arc and arc-suppression coil.At the same time,the line selection scheme has low requirements for hardware configuration and can be configured in line protection devices,which has good practical value.