Innovative Railway Traction System

This article describes the future Alstom railway traction systems developed as part of “Shift2rail”. This
innovative system is based on silicon carbide (SiC) high power density converters, high efficiency transformers,
increased speed motors to improve the whole traction system efficiency. SiC semiconductors (MOSFET) have
lower losses than silicon IGBT and will operate at higher junction temperature (175°C). The reduction of the
power converters’ losses (-50% total losses) enables the cooling system to be simplified and compacted.
Globally, we expect important achievements in terms of train energy consumption (-10% at train level), mass
and volume reduction, positive impact regarding the reliability (elimination of cooling pumps and fans), better
availability and noise reduction, in order to design innovative, environmentally friendly, economy efficient rail
solutions.