中文摘要：

谐振接地系统发生单相接地故障时,有源电压消弧法的灭弧性能缺少分析和论证。在考虑线路压降的情况下,给出了有源电压消弧后的故障点电流表达式及变化规律,表明在故障点过渡电阻较大时,有源电压消弧可以有效补偿故障点电流实现可靠消弧,而在过渡电阻较小、负荷电流较大、故障距离较远时,有源电压消弧反而会导致故障点电流变大,甚至达上百A,严重影响熄弧效果。提出有源电压消弧算法的改进措施,低阻接地时将故障相电压控制到一定范围内,确保故障点电流不会增大,该方法无需测量系统参数,可适应线路结构的动态变化,有利于有源电压消弧法在现场实际中的应用和完善,仿真验证了分析及改进算法的正确性。

英文摘要：

For single-phase earth fault occurring in resonant grounding system, there is few analysis and demonstration about performance of traditional active voltage are-suppression method. Considering line voltage drop, this paper gives expression and variation law of injection current of active voltage arc-suppression method and fault point current after active voltage arc-suppression. When fault transition resistance is large, active voltage arc-suppression method can effectively compensate fault point current to realize reliable arc-suppression. If fault resistance is relatively low, load current is large and fault distance is long, active voltage arc-suppression could lead to larger fault current, even up to hundreds of amperes, seriously reducing arc-extinguish effect. So this paper puts forward an improved active voltage arc-suppression method, limiting fault phase voltage and current for low resistance grounding fault within a certain range to prevent fault current increasing. This method doesn＇t need to measure system parameters. Therefore, it could adapt to system structure variation with advantage of easy application and improvement. Validity of the analysis and the improved algorithm is verified with simulation.