Resonant switched capacitor converter based DC auto-transformer for urban rail transit

In order to solve the stray current issue of urban rail transit, DC auto-transformer traction power supply system (DCAT-TPSS) has been studied. However, due to high current level in the TPSS, Basic-DCAT has some deficiencies in the power density and efficiency. So the resonant switched capacitor converter based DC auto-transformer (RSCC-DCAT) is proposed in this paper, which greatly improves the performance of DCAT-TPSS. The configuration, operation principles and comparisons between RSCC-DCAT and Basic-DCAT are discussed in detail. Finally, a 4 kW experimental platform is developed and constructed, and the experimental results verify the feasibility and validity of analysis for RSCC-DCAT.