0.4 kV供电系统剩余电流保护参数整定及安装位置的选择

Protection Parameter Setting of Leakage Current and Installation Location Selection for 0.4 kV Power Supply System

分析了配电变压器二次侧剩余电流保护器频繁跳闸的原因,主要是电力用户侧尚未全部安装剩余电流保护器,少数剩余电流保护器拒动;低压线路年久失修,一遇到阴雨天气,绝缘老化破损处的剩余电流沿导线上的雨水通过大地流回到电源,造成主剩余电流保护跳闸。针对这些问题,根据GB 50054—2011《低压配电设计规范》要求,对保护参数及安装位置进行调整,避免剩余电流造成的越级跳闸事故。

This paper analyzed the frequent tripping cause of the main leakage protective device of the distribution transformer secondary side. The main cause is that the power user side has not yet been installed leakage protective device,and there are maloperation for a few leakage protective devices. On the other hand,the disrepair low line encounters a rainy weather,and the leakage current of the insulation aging and brearking line returns to the power supply along the rain on wire through the land flow,which is the main cause of leakage protection tripping. According to the requirements of GB 50054—2011,the protective parmeter setting and installation location of leakage protective device were adjusted,in order to prevent the tripping accidents caused by the leakage current.