Research on matrix-based algorithm for single-phase-to-earth fault section location in distribution grid

Due to the large amount of branches and high grounding resistance of distribution grid, the grounding fault location has not been solved effectively. The matrix-based live location method is proposed for single-phase-to-earth fault section in distribution grid. Fault message character matrix is designed according to the data measured by FTU. For neutral point insulation system, the element of character matrix is the phase difference between zero-sequence voltage and zero-sequence current measured by FTU. For neutral point grounded by arc-suppression coil system, the element of character matrix is the variant of zero-sequence-current measured by FTU using the theory of remnant current increment. Through analysis of character matrix using united criterion, fault section is determined and the solution is analyzed when fault information is not completed. The correctness and feasibility of this technology has been fully approved by site experiments.