基于小波分解-暂态信号的综合极性比较故障选线法

A Novel Method of Ground Fault Line Selection on Non-solid earthed network Based on wavelet packet analysis and transient signal

在详细分析了非有效接地系统发生单相接地故障时各条馈线零序电流暂态特征的基础上,结合小波包理论,提出了小波分解-暂态信号的综合极性比较故障选线法。应用该方法对各条馈线在故障时刻的暂态零序电流进行分解研究,通过对选定频段内计算系数的极性进行比较,寻找判断出发生故障的馈线。利用PSCAD进行10 k V配电网模型故障仿真,结果表明所提算法能够在规定的各种工况下可靠准确地进行选线。

On the basis of a detailed analysis of the char- acteristics of the transient zero sequence current of each feeder when a single-phase earthing fault occurs to the non-effectively earthed system, and in according to the wavelet packet theory, a novel method is proposed for the detection of the fault line based on wavelet packet in this paper. The transient zero se- quence current is decomposed by using wavelet packet, and the fault line is identified by comparing the sign of the coefficients in SFB （selected frequency band）. Finally, PACAD is used to build a model of 10 kV distribution network and the simulation has verified that the proposed method is reliable for the fault line selection under various operating conditions.