Mitsubishi Electric has launched a railcar traction inverter system for 1,500V DC catenaries designed using all-silicon carbide (SiC) power modules made with SiC transistors and SiC diodes. The all-SiC inverter is 55% more power efficient than insulated gate bipolar transistor (IGBT) power modules and is also better than hybrid power modules made with Si transistors and SiC diodes.
The new system helps in increasing regenerated energy through the use of regenerative brakes in all speed ranges. Mitsubishi claims the total energy consumption of railcar systems, including their motors, is reduced by about 30% compared to conventional systems.
Other advantages include size and weight are reduced by about 65% compared to conventional inverter systems with IGBT power modules and about 30% compared to existing hybrid inverter systems with SiC diodes.
The number of components is reduced by integrating SiC transistors and diodes into one package per inverter circuit phase.
Energy saving in total railway systems is further enhanced by effectively transferring regenerated electric power from the railcar to stations to be equipped with Station energy-saving inverters (S-EIV).