不对称小电流接地电网单相接地电流的测量

Measuring Method of the Single-phase-to-ground Current in the Indirectly Grounded Asymmetrical Powers System

介绍了简单易用、测量精度高的不对称小电流接地系统单相接地电流的测量方法。该法分别将三相经电阻接地,测得经电阻接地的接地电流值、相电压值和零序电压值即可方便地计算出电网的单相接地电流大小,还可区分出其有、无功分量,无功分量为容性或感性。现场测量结果证实了该法的有效性。

This paper proposes a simple, convenient and relatively accurate method for measuring currents, i. e. , to connect a resistance between three phases conductor and the ground respectively, and then measure the currents flowing in the resistance, the phase voltages and the zero-sequence voltages. With these measured data, the single-phase-to-ground current wherever the network can be calculated. This method not only can measure the maghitude of the single-phase-to-ground current, but also can distinguish its active and reactive components and determine whether the reactive component is capacitive or inductive. Field measuring results have verified the feasibility of this method.