我国110kV及以上电网一般采用大电流接地方式，即中性点有效接地方式（在实际运行中，为降低单相接地电流，可使部分变压器采用不接地方式），这样中性点电位固定为地电位，发生单相接地故障时，非故障相电压升高不会超过1.4倍运行相电压；暂态过电压水平也较低；故障电流很大，漏电保护能迅速动作于跳闸，切除故障，系统设备承受过电压时间较短。因此，大电流接地系统可使整个系统设备绝缘要求水平降低，从而大幅降低造价。

China's 110kV and above power grids generally adopt the high current grounding mode, i.e. the neutral point effective grounding mode (in practice, in order to reduce the single-phase grounding current, some transformers can adopt the non-grounding mode), so that the neutral point potential is fixed to ge.75ix.comdugebang.75ix.comwww.yeyadabaoji.com.cnwww.hfguoyu.cnwww.dispLay0755.com.cn

www.coron.com.cnthe ground potential, when single-phase grounding fault occurs, the non-fault phase voltage will not rise more than 1.4 times of the operating phase voltage; The fault current is very large, the leakage protection can quickly operate in tripping, removing the fault, and the system equipment can withstand the overvoltage for a short time. Therefore, the high current grounding system can reduce the insulation requirements of the whole system equipment, thus greatly reducing the cost.