随着电力系统的发展，配电网采用的电缆线路越来越多，电缆线路的增加导致系统电容电流急剧增加，在中性点不接地的运行方式下电容电流的不断增加对设备绝缘的安全和保护设备的配备带来了严重影响。
With the development of power system, more and more cable lines are used in distribution network. The increase of cable lines leads to the sharp increase of system capacitance current. Under the operation mode of ungrounded neutral point, the continuous increase of capacitance current has a serious impact on the safety of equipment insulation and the allocation of protection equipment.
因此，我国在山刷房 保定网站建设 保定强夯 卷扬式启闭机  保定网站制作 收费岛模具 遮阳网 麻绳1997年颁布的DL/T620-1997标准规定当系统电容电流超过10A时，中性点需经消弧线圈接地线电压保持不变，允许继续运行2h，对提高供电可靠性、电气设备和线路的绝缘水平、减轻对通信系统的干扰等方面具有很好的保护作用。
Therefore, the DL / t620-1997 standard issued in 1997 stipulates that when the capacitance current of the system exceeds 10a, the voltage of the neutral point through the arc suppression coil ground wire shall remain unchanged, and it is allowed to continue to operate for 2h, which has a good protective effect on improving the reliability of power supply, the insulation level of electrical equipment and lines, reducing the interference to the communication system, etc.
但其单相接地故障线路的选择也是困扰电力工作者的一个难题，正确选择中性点接地方式对确保配电网的安全运行十分必要。
However, the selection of single-phase ground fault line is also a difficult problem for power workers. It is necessary to select the correct neutral point grounding mode to ensure the safe operation of the distribution networ