基于暂态高频零序瞬时功率的配电网故障选线方法

Method of distributed power system fault line selection based on transient high frequency instantaneous zero-sequence power

在配电网故障特征的基础上,利用小波包分析技术提出了一种基于暂态高频零序瞬时功率的配电网故障选线新判据,解决了小波应用中频带选取困难的问题。该判据以幅值最大高频暂态瞬时功率的符号作为主判据,以大小作为副判据。仿真表明该选线方法对接地阻抗、故障距离、短线远端接地等故障均能准确判断,且不受中性点接地方式、故障接地时刻等因素的影响,具有良好的通用性。

According to distributed power system fault characteristic, a new criteria based on the transient high frequency instantaneous zero-sequence power is put forward to distinguish the fault line in this paper with multi-resolution analysis of wavelet and the difficulty of frequency zone selection in wavelet application is overcome. The sign of the maxim high frequency instantaneous power is the fu＇st criteria and the value of the power is the second criteria in the new criteria, The simulation suggests that the new criteria could distinguish correctly the fault line under various grounding impedance and fault distance, whose performance is independent on the grounding model of centric dot and fault occurring time, and the new criteria has a excellent adaptability to various fault conditions.