基于相电流突变量固有模态能量的选线新方法

摘要

针对传统零序电流能量选线方法在小电流接地系统的混合线路应用中选线效果不佳的问题, 提出一种基于相电流突变量固有模态能量的选线方法.该方法以每条线路各相电流突变量为特征向量, 计算其固有模态能量及每条线路模态能量极大值, 最大模态能量极大值所对应的线路即是故障线路.仿真结果表明, 与利用零序电流能量选线法相比, 此方法选线准确度较高, 受接地电阻、故障合闸角、接地位置、系统结构影响较小, 更适应结构比较复杂的配电网系统选线.%Since the traditional line selection method based on zero-sequence current energy does not work well in the application of hybrid line for small current grounding system, a new line selection method is proposed based on the intrinsic mode energy of phase current change.The phase current change in each line is selected as the feature vector, then the intrinsic mode energy and the maximum modal energy of each line are calculated for the judgment that a line with the maximum intrinsic mode energy is the faulty line.Compared with the line selection method based on zerosequence current energy, the simulation results show that this new method has higher accuracy of line selection, less influence by grounding resistance, fault closing angle, grounding position and system structure.Therefore, it is suitable for the fault line selection of distribution network system with more complicated structures.