Simplified models of electric railway substations for three-phase power-flow studies

Simplified models of electric railway power-supply substations for three-phase power flow studies have been developed and are introduced in this paper. By these suitable substation models, detailed studies on the effects of large unbalanced traction loads on its power-supply system can be performed directly by using existing three-phase power flow programs. Furthermore, the related improvement projects can be judged and conducted if necessary. Various transformer connection schemes that are commonly used in the power-supply substations to supply electric railway demands are considered. The connection schemes include single-phase, V, Scott, and Le Blanc connection