矿井供电系统弧光接地过电压形成过程研究

Research on formation process of arc grounding over-voltage in mine power supply system

为全面研究矿井供电系统弧光接地过电压形成过程,采用实时数字仿真仪搭建了矿井供电系统模型和间歇性电弧接地模型,分别对工频熄弧、高频熄弧及工频熄弧与高频熄弧同时存在的混合熄弧过程中过电压进行了仿真研究。结果表明:工频熄弧理论条件下暂态过电压最大值略低于历史实测值;高频熄弧理论条件下暂态过电压最大值随电弧重燃次数的增加而增大,且暂态过电压最大值高于历史实测值;混合熄弧情况下,高频熄弧出现次数越多且连续出现时,暂态过电压最大值越高;矿井供电系统发生电弧接地故障时,一般表现为工频熄弧与高频熄弧间隔出现的状态,高频熄弧连续出现3次以上的概率很小。

For comprehensive research on formation process of arc grounding over-voltage in mine power supply system,a mine power supply system model and an intermittent arc grounding model were built by use of real time digital simulator,and over-voltages in processes of power frequency arc extinction,high frequency arc extinction and hybrid arc extinction were simulated.The simulation results show that the maximum transient over-voltage under condition of power frequency arc extinction theory is slightly lower than historical measured value;the maximum transient over-voltage under condition of high frequency arc extinction theory increases with the increase of arc re-ignition times,which is larger than the historical measured value;in the case of hybrid arc extinction,the more times high frequency arcextinction occurs and occurs continuously,the larger the maximum transient over-voltage is;when arc grounding fault occurs in mine power supply system,power frequency arc extinction and high frequency arc extinction alternately occurs,and probability is very low that high frequency arc extinction continuously occurs more than three times.