摘要
通过矿井安全、漏电故障、过电压等方面的理论研究，对煤矿井下3．3kV电网中性点的接地电阻进行了全面的分析，利用计算机对不同中性点接地电阻值的故障界态过程进行仿真，并在实验室用3．3kV模拟电网进行了参数测试，给出了故障电流和过电压概率分布曲线。理论分析证明，中性点接地电阻较小时故障点漏电电流较大，对煤矿和人身安全构成一定威胁，但可有效限制电弧过电压和不对称短路过电压的幅值及发生概率，有利于电气设备的绝缘安全。综合分析认为，中性点电阻宜取值1．77-10．6kΩ。
The thesis studies the neutral grounding resistance of 3. 3 kV underground power system from view of mine safety, leakage fault and over-voltage etc. These transient fault parameters are emulated in the computer. The measurement of electric parameters is done in simulating 3. 3 kV power system. The distributed probability of leakage fault current and over-voltage is given. When the neutral resistance is small, the leakage fault currentis big. That has threatened to the safety of coal mine and worker, but it can restrict the amplitude and probability of arc ground over-voltage or asymmetric short circuit over-voltage at same time, that is beneficial to the insulation safety of electric equipment. By theoretic analysis, the range of neutral resistance is from 1.77 kΩ to 10. 6 kΩ. The best range of neutral resistance from 2 kΩ to 5 kΩ is commended.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2006年第3期90-92,117,共4页
High Voltage Engineering
关键词
井下供电系统
中性点
接地电阻
漏电电流
过电压
人身安全
underground power system
neutral point
grounding resistance
leakage current
over-voltage
safety of person
