基于小波分析法进行单相接地故障选线的研究

Research on single-phase grounding fault line selection based on wavelet analysis

针对配网小电流接地系统中单相接地故障时常发生,对电网的稳定运行造成一定的影响,必须及时的选出并切除故障线路,提出一种基于小波分析的配网故障选线方法,小波分析是一种时域-频域分析方法,能够提取突变信号在各个时频的特征,成为分析暂态突变信号的有效工具。电力系统故障时,通常表现为电压、电流信号的某种突变,因此,利用小波变换对信号的突变和奇异性较敏感的特性来检测故障线路十分有效。

According to the single -phase grounding fault in small current grounding system of distribution network always bappened, which had affected to the stability of power grid and must be timely elected and removed, this paper proposed a fault line selection method based on wavelet analysis. Wavelet analysis was a method based on time - domain and frequency domain, it could extracted the frequency characteristics or time - domain characteristics of transient signals in the various time, and became an effective tool to analyze transient mutation signal. The voltage and current signals would happened a series of mutations while the power system was faulted, therefore, using wavelet transform signal mutations and the singularity to detect the fault line was very effective.