应用改进型有功分量法的小电流接地选线

通过分析基于稳态信号的有功选线原理,以及该方法影响选线准确率的原因,提出了一种消除不平衡电流的零序有功选线新方法。该方法通过算法消除电网不平衡电流,计算出各支路实际的故障零序电流幅值和相位,还原了故障支路和非故障支路的有功分量差异,从而提高了选线的准确性。利用PSCAD进行相应的仿真计算,结果表明,基于该方法选择性接地保护故障支路与非故障支路动作差值较大,准确性高、抗干扰能力强,而且不易受故障相接地相位及接地方式和接地阻值的影响。

Fault Line Selection in Small Current Grounding System by Improved Active Component Method

By making a thorough analysis of active line selection principle based on stable signal and the course of factors affecting the accuracy of line selection,a novel zero-sequence active line selection method which can eliminate the influence of unbalanced current is proposed.In the method,the amplitude and phase of actual fault zero sequence current are calculated so as to eliminate the influence of unbalanced current in the grid and enlarge the differences of active component between the fault feeder and the...