Graph Theory-Based Fault Location Method for Transmission Systems With Renewable Energy Sources

Fault location has been crucial in minimizing fault restoration time. Various techniques and methodologies have been deployed to enhance the performance of fault location algorithms, especially in light of the increasing integration of renewable energy sources. In this context, this paper describes a graph-theory-based method for fault location in power networks with renewable energy sources. This novel technique is designed to provide accurate fault distance estimates, even in the presence of severe noise and fault resistance. It takes advantage of graph theory and equivalent impedances applying Kirchhoff’s laws systematically to ensure accurate fault location even in the presence of fault resistances. To showcase the improved accuracy of the proposed methodology, a comparison with typical impedance-based two-terminal fault location methods is carried out. The effectiveness of the proposed algorithm was proven with different electrical systems. Average errors inferior to 0.22% and 0.48% were obtained for single-phase faults and three-phase faults with resistances up to $200~\Omega $ respectively, which confirms the improved performance with respect to conventional algorithms implemented in typical impedance relays.