Fault Location Method Based on Zero-sequence Admittance of Sections in Non-effectively Grounded System

A novel location method for single phase-to-earth fault based on zero-sequence admittance of feeder section in non-effectively grounded system is presented.Each feeder of the distribution network is divided into several sections by the sectionalized switches.The criterion for faulty section based on zero-sequence admittance is discussed on the basis of analyzing zero-sequence admittance characteristics of sound section and faulty section.By using the feeder terminal unit(FTU) as field measurement equipment,this method for fault location can be implemented in distribution automation(DA) system.The results of digital simulation demonstrate that this method is immune to the variation of system operation mode,feeder parameter and transition resistance etc.,it has a high location accuracy and can meets the practical requirements.