煤矿井下电网选择性漏电保护原理

Selective Leakage Protection Principle of Under -ground Network for Coal Mine

阐述了目前矿井低压供电系统中漏电保护纵向选择依靠延时来实现所存在的问题,提出了基于零序电流方向和单片机通讯相结合的后备保护原理,从而使总、分开关之间的漏电保护的动作时间控制在50ms之内。

This paper describes the existing problems in leakage protec tion of low-pressure power supply system for mine and puts forward the back-up protection principle based on the combi nation of zero-sequence current direction and single-chip com puter com-munication,thus limiting the actuating time of leak age protec-tion between main and branch switches in50ms.