Detection of arc grounding fault in distribution network based on the harmonic component

The single-phase arc grounding fault is a main fault form in medium voltage distribution networks. Studies on modeling and simulation of arc help to choose arc-extinction methods and line-selection methods. In this paper, three kinds of common arc mathematical equations are analyzed, such as the Mayr, Cassie and Schwarz model. Then the total harmonic distortion rate and the harmonic content in distribution networks of those models are analyzed and compared. Based on the analysis results, it is proposed that the arcing faults can be detected by monitoring the total harmonic voltage distortion rate and the third harmonic voltage content in non-fault phase. The comparison was carried out to determine whether the harmonic detection method of arcing faults is applicable to three common arc models. Finally, the field measurements of arc grounding faults and grassland grounding faults are discussed in detail, which proves that the total harmonic voltage distortion and the third harmonic voltage of the non-fault phase can be used as the index to distinguish the arcing faults from the normal load to ground faults.