10kV配电网单相接地电容电流的工程计算法探讨

Measuring method of one-phase grounding capacitive current in 10 kV distribution network

10 kV配电网中性点采用经小电阻接地方式或经消弧线圈接地方式,关键问题是10 kV母线接地电容电流值的计算是否正确。简要介绍了配电网中的小电流接地系统中的单相接地电容电流的组成,论述了电容电流工程计算法是判断新建工程项目是否装设小电阻或消弧系统的有效手段,分析了不同情况下单相接地电容电流的算法,通过对110 kV变电站10 kV母线电容电流进行现场测量并和计算值对比的实例,分析和验证了该工程计算方法具有很高的精度,可以大力推广应用。

As for 10 kV distribution network with small neutral point grounding resistor or arc-suppression coil, the key problem is whether the calculation of grounding capacitive current in 10 kV main bus is right. This paper introduces the composition of one-phase grounding capacitive current in weak current grounding system, and points out the calculation method of capacitive current is an effective way for judging if it needs to equip the small grounding resistor or arc-suppression coil in a new project. The different calculation methods of one-phase grounding capacitive current in various condition are analyzed. The real case that comparing the theoretical calculation with practical measurement of capacitive current in 10 kV main bus in 110 kV substation verifies the measuring method is very precise, and it is worthy to be applied widely.