摘要
电力系统10~35kV系统多采用中性点不直接接地方式。随着城市电网建设规模的迅速发展,变电站的电力电缆出线越来越多,导致电网单相接地电容电流不断增大。系统发生单相接地故障时,电容电流大,接地点电弧不易熄灭产生弧光过电压,引发电力系统事故。中性点经消弧线圈接地,补偿了接地电容电流,限制弧光接地过电压,保证电网供电可靠性和电网的安全。采用自动跟踪补偿后,能实时适应负荷线路接地的变化实现高精度、快速可靠的自动调节。
10~35kV power system mainly adopts neutral point undirected earthing. With the progress of city power grid, the numbers of outgoing lines from the substation is increased greatly, which results continuous increasing of power capacity and current of single phase earthing. When the system's single earthing fails, because power capacity and current is greater, the arc is hard to be extinguished and arc over-voltage may cause power system failure. But neutral point is earthed by arc coil, which compensates earthing power capacity and current, restricts arc earthing over-voltage and ensure safety and reliability of operation of power system. The adoption of auto-tracking compensation, automatic regulation of earthing for different loads is realized in a accurate and rapid way.