基于小波包分析的低压配电系统接地故障诊断

Grounding Fault Diagnosis of Low Voltage Distribution System Based on Wavelet Packet Analysis

传统方法在低压配电系统接地故障诊断中应用效果不佳,不仅错诊率比较高,而且召回率比较低,无法达到预期的故障诊断效果,为此提出基于小波包分析的低压配电系统接地故障诊断。利用无线传感技术采集系统运行电压信号,并对其进行标准化处理,利用小波包分析技术分解电压信号,提取接地故障特征向量,根据特征向量确定低压配电系统相对误差与绝对误差,识别诊断出低压配电系统是否存在接地故障,以此实现基于小波包分析的低压配电系统接地故障诊断。经实验证明,该设计方法错诊率低于1%,召回率高于95%,在低压配电系统接地故障诊断方面具有良好的应用前景。

Traditional methods are inferior in diagnosing grounding faults in low-voltage distribution systems,as the misdiagnosis rate is relatively high and the recall rate is low,which cannot achieve the expected fault diagnosis effect.Therefore,a wavelet-packet-analysis-based method to diagnose low-voltage distribution system grounding faults is proposed.The wireless sensor technology is used to collect the and standardize operating voltage signal of the system.The wavelet packet analysis technology is used to decompose the voltage signal,extract the grounding fault feature vector,determine the relative error and absolute error of the low-voltage distribution system according to the feature vector,identify and diagnose whether there is a grounding fault in the low-voltage distribution system,and thus realize the grounding fault diagnosis of the low-voltage distribution system based on the wavelet packet analysis.Through experiments,it has been proven that the designed method has a misdiagnosis rate of less than 1%and a recall rate of higher than 95%,which has good application prospects in the diagnosis of grounding faults in low-voltage distribution systems.