Equivalent Scheme for Calculating Short-Circuit Current in an Alternating-Current Electric Traction Network

Resumo

The authors have proved the feasibility of substitution of a three-phase power-supply system with a single-phase one when calculating three-phase circuits in electric traction network irrespectively of the external power supply arrangement. In addition, calculation features have been established for particular transformer winding connection configurations (Y/Y or Y/Δ). Based on results of an analysis performed for minimizing the methodological error in calculating the short-circuit currents, a single-phase equivalent circuit has been developed for the intersubstation zone of the traction network, which takes into account the connection between two adjacent substations via an overhead transmission line of 110 (220) kV. An example of calculation in accordance with the proposed replacement scheme is given.