Research On Line Selection Technology Of Small Current Grounding System

When the single-phase ground fault occurs,with high possibility,the three-phase distribution network system remain symmetrical,and the system could still run with fault,which may brew a larger fault and endanger equipment health.Small current grounding system plays an important role in ensuring the reliability of operation system,which provides support for distribution network fault diagnosis by analyzing the fault characteristic of normal lines and fault lines,both on transient state and steady state.Although several studies have been researched on the line selection technology of the small current grounding system,the distribution network structure is relatively complicated,especially being susceptible to transient faults and other related factors.Thus,there are some differences in application of most of the positioning methods.In this regard,it is necessary to continue to study on the small current grounding fault in the actual distribution network environment,for proposing an effective fault location method based on this system state.In this paper,different line selection techniques for small current grounding system are discussed.There are five chapters in this study,focusing on the analysis of the technology of selecting the line of the small current grounding system.Based on the comprehensive analysis of small current grounding system with single-phase grounding fault,different comprehensive line selection methods are put forward and discussed.Then,the fault line selection technology based on SVD algorithm is analyzed,and the main component correlation analysis of zero sequence transient current and the detection method of sudden change direction of zero sequence transient current are put forward.The specific fault line selection steps and data simulation detection analysis are proposed.The signal selection and detection analysis,line selection steps and data simulation of each method are discussed to complete the fault line selection technology analysis based on the SVD algorithm.The method proposed in this paper provides an effective method for line selection of small current grounding system,which has a great value for small current grounding system.