Converter Topologies for MVDC Traction Transformers

The paper compares the conventional railway traction systems with new traction systems proposed and developed in the last decade that are also suitable for the medium voltage DC (MVDC) railway electrification concept presented in this project. Differences and requirements of the MVDC traction system will be considered while investigating converter topologies for MVDC transformers (Power Electronic Traction Transformers - PETTs or Solid State Transformers SSTs). Then, the paper will focus on presenting the most suitable DC-DC converters for this application, defining an example of optimal configuration and requirements of control, which in the future can be further developed for a novel MVDC railway electrification's traction systems on-board.