A Model of a Combined Subway Traction Substation Taking Traction Load and Consumers’ Auxiliaries into Account

Specific features of operations of auxiliaries of a combined traction substation (CTS) including the effects of traction load are considered. A symbolic circuit of a simulation model of an actual Moscow subway CTS is presented. The main objects of the study—consumers of automobile-engine transformers and lighting and signaling systems—are described, which are taken into account in the simulation of CTS operations that also includes a traction-network segment with trains and an external power-supply system. The instability of voltage on 10- (20)-kV CTS buses and the asymmetry level are shown in qualitative and quantitative terms. Similar oscillograms are also presented for an end consumer—a motor engine—with similar deviations in the electric power quality. The simulation results have been statistically processed. An engineering solution is proposed that consists in using a dc link with energy-storage units to enhance the quality of the power supplied to the CTS’ essential auxiliaries.