基于多故障特征量提取的配电网单相接地故障类型识别

对配电网发生的故障进行准确的在线识别,有助于快速处理故障。提出一种基于多故障特征量提取的配电网单相接地故障类型识别方法。首先,从故障持续性、过渡电阻大小、故障点燃弧性质3个特征对单相接地故障进行多特征分类。然后,将小波多分辨率分析与数学形态学相结合,提取故障相电压的暂态脉冲信号,并由其识别故障暂态产生次数,判断故障持续性;由故障后的中性点电压偏移量,估算过渡电阻大小;提取故障相电压的总谐波畸变率,判断故障点是否存在燃弧现象。最后,依据以上故障特征量,提出配电网单相接地故障总识别流程,并通过仿真验证了该方法的可靠性。

Distribution Network Single-phase Grounding Fault Type Identification Based on Multi-fault Feature Extraction

The accurate online identification of the faults in distribution network is helpful to deal with the faults quickly.A multi-feature classification and recognition method for single-phase grounding fault in distribution network is proposed.This paper classifies single-phase grounding faults into three characteristics according to fault persistence,transition resistance and arc character.The high frequency singular signal of fault phase voltage is obtained by using wavelet multi-resolution analysis and mathematical morphology.Based on the results,the generation times of fault transient components are estimated to judge the continuity of faults.The voltage offset of neutral point is used to estimate the transition resistance.Whether arc phenomenon is exist at fault point is judged by total harmonic distortion rate of fault phase voltage.Finally,according to the above fault characteristics,the identification process is proposed,and the simulation model is established and the reliability of the method is verified by simulation.