小电流接地电网改进能量法接地选线原理

根据小电流接地电网单相接地故障时电压电流的变化特点,利用中性点电压、故障相电压和零序电流构造的能量曲线的斜率来进行故障选线。该方法不受电网平衡情况和接地电阻大小的影响,对复杂的间歇性电弧接地故障同样有效。MATLAB仿真证明了本文的结论是正确的。

Improved energy function to detect the grounded line in neutral point indirectly grounded network

In this paper, a new method of energy function to detect single-phase earth fault in neutral point indirectly grounded network is presented. This method is based on the slope of energy curve constructed by neutral voltage, fault phase voltage, and zero-sequence current to detect the fault line. It is immune from the unbalanced status of network and the values of earthed resistance. To the complicated intermittent arc-earth fault, the proposed method also works well. MATLAB simulation verifies the points of the paper.