Faulted Line Detection Using Time-Frequency Information for Distribution System

The fault diagnosis technology of the distribution system is an important guarantee for the stable operation of the distribution network, and the fault line detection method is the premise of fault diagnosis. Based on the analysis of the characteristics of zero-sequence current when a single line-to-ground (SLG) fault occurs in the non-solidly earthed network, this paper proposes a fault line detection method that comprehensively uses the time-domain direction and spectral energy of the zero-sequence current, which can adapt to frequent changes in the operation mode of the distribution network. The effectiveness of the method is verified by a large number of simulation and field data.