关于某地区电网110kV系统增加中性点接地的分析计算

某地区110 kV电网是以一个220 kV变电站为电源中心呈辐射状向各负荷变电站供电。为了保持电网零序网络的相对稳定,仅选择在220 kV变电站一台主变220 kV侧和110 kV侧中性点直接接地。一旦发生110 kV侧中性点失去的情况下,当110 kV系统发生接地故障时,将在110 kV系统产生很高的零序电压,引发主变跳闸的大面积停电事故。针对增加110kV系统接地点进行分析计算,提出了增加中性点接地的最佳方案。

On a regional power network110kV system to increase the neutral point grounding analysis and calculation

In a certain area of 110 kV power grid is a transformer substation of 220 kV power center for the axles of the substation to load power supply,in order to maintain the power grid zero sequence of network relatively stable,only in 220 kV substation a main transformer 220 kV side and 110 kV side neutral grounding directly is choosed.Once produce 110 kV side neutral lost case,when 110 kV system when earthing fault occurring,will be in 110 kV system to produce high zero sequence voltage,cause the main transformer power feeder of the accident of large area.Aimed at increasing 110 kV system take place to carry on the calculation and analysis,it presents the increase of neutral grounding the best solutions.