煤矿供电越级跳闸问题解决方案研究

Study on Override Trip Solutions Plan of Coal Mine Power Supply System

针对煤矿供电系统中常存在井下短路越级到地面变电站跳闸,导致井下大面积停电,生产停顿,严重时甚至造成局部瓦斯积聚,影响安全等问题。笔者结合煤矿供电系统的特点,理论分析了导致煤矿短路越级跳闸的5种原因,即整定方法不合理、短线路、系统运行方式差异较大、失压保护、CT与短路电流值不匹配。针对煤炭系统目前应用的电流纵联差动保护、通信级联闭锁、数字化集成保护、智能变电站区域集控的4种防越级跳闸方案,分别分析了其技术原理,并从应用角度总结了其优缺点。分析表明基于智能变电站区域集控的防越级系统功能强大,是未来煤矿供电系统的发展方向。

According to the problem of override trip accidents which happened in the ground substation caused by the faults of underground coal mine substation, and the override trip accidents could cause widespread blackout in underground mine, even could cause the gas accu- mulation. In combination with characteristics of coal mine power supply system, the paper analyzed five reasons of override trip accidents in coal mine, which were the unreasonable setting methods, short lines, the large differences in the power system running mode, under-voltage protection, the no fitting between CT and the value of short-circuit current. And it introduced four typical anti-override trip protection schemes, which were based on the theory of current longitudinal differential protection or trip interlocking or digital integrated protection or smart substation multi-area centralized control.Technical principles of four scheme were analyzed and their advantages and disadvantages were summarized from the view of application.The analysis showed that the override trip protection system based on the theory of intelligent substation centralized control had powerful functions and it was the development of coal mine power supply system in future.