基于衰减电流分量的双树复小波相位选线原理

Line Selection Principle Using Dual-tree Complex Wavelet Phase Based on Decaying Current Component

过补偿情况下,在对小电流接地故障特征详细分析的基础上,发现故障线路与正常线路存在着衰减电流的差别,此差别电流反映在复小波变换相位上体现为相位的延迟,据此,通过采用具有时移不变性的双树复小波构造相位选线算法从而避免了实小波分解结果的不确定性,另外也对过补偿情况下相位选线失效的问题提出了一个新的解决方案。仿真实例验证了所提出的算法有效、可行性。

Based on the analysis of fault features of neutral un - effectual grounded system in the case of overcompensation, it is found that there are some differences of decaying currents between fault line and normal hne. These differences are presented as the delay of phase in complex wavelet transform phase relationship. So a line selection method based on dual - tree complex wavelet which possesses the characteristics of shift invariant is proposed, as a result, the uncertainty of real wavelet analysis results can be avoided. In addition, this method proposes a new solution scheme towards line selection failure problem in overcompensation situation. At last, the simulation examples prove the effectiveness of the proposed algorithm.