电源感应电势中本身就存在高次谐波分量，此外由于变压器、电压互感器等设备铁心非线性的影响，电网中必然包含一系列高次谐波分量，其中主要为5次谐波分量。对中性点经消弧线圈接地的系统，由于消弧线圈对5次谐波呈现的感抗为基波的5倍，而线路容抗为基波1/5，和线路容抗相比，消弧线圈近似于开路状态。
In the power system, there are high-order harmonic components in the induction potential of power supply. In addition, due to the non-linearity of transformers, voltage transformers and other equipment cores, a series of high-order harmonic components must be included in the power grid, mainly the fifth harmonic component. For the system whose neutral point is grounded by arc suppression coil, the inductance of arc suppression coil to the 5th harmonic wave is 5 times that of the fundamental wave, and the line capacitance is 1/5 of the fundamental wave. Compared with the line capacitance, the arc suppression coil is close to the open circuit state.
因此，5次谐波感性电液压钢坝流保定平面设计培训 保定空调维修 保定管道通风 包装盒定做 化粪池模具 废旧电缆回收 不锈钢铸件 可以忽略，系统单相接地时，5次谐波容性电流分布与中性点不接地系统中基波容性电流几乎相同，籍此可进行故障选线。
Therefore, the 5th harmonic inductive current can be neglected. When the system is single-phase grounded, the 5th harmonic capacitive current distribution is almost the same as that of the fundamental capacitive current in the neutral-point ungrounded system, which can be used for fault line selection.