10 kV混合线路中性点接地电阻的选择

Selection of Neutral Grounding Resistance of 10 kV Hybrid Line

本文分析了混合线路在未采取中性点接地时电压分布情况,分析了经电阻接地方式下接地电阻在取值不同时线路上最大电压幅值变化趋势,同时研究了流经故障点和中性点电流幅值随接地电阻关系,得出了不接地系统的过电压幅值在燃弧期间呈增加趋势,在经电阻接地方式下电压幅值在多次燃弧期间保持平稳,中性点接地电阻取合适阻值时线路上过电压幅值最小,且流经故障点和中性点电流得到控制。

In this paper,the voltage distribution of the hybrid line is analyzed when the neutral point is not grounded.The variation trend of the maximum voltage amplitude is analyzed on the line when the grounding resistance is different under the resistance grounding method.At the same time,the fault point and neutrality are studied.The point current amplitude has a relationship with the grounding resistance,and it is concluded that the overvoltage amplitude of the ungrounded system increases during the arcing period;in the resistance grounding mode,the voltage amplitude remains stable during multiple arcing.When the resistance is a suitable resistance,the voltage amplitude on the line is the smallest,and the current flowing through the fault point and the neutral point is controlled.