Mitsubishi Electric Corporation announced that it has launched a railcar traction inverter system for 1,500V DC catenaries that incorporates the world's first all Silicon Carbide (SiC) power modules made with SiC transistors and SiC diodes.
The all-SiC inverter greatly reduces power loss, size and weight compared to conventional Insulated Gate Bipolar Transistor (IGBT) power modules and hybrid power modules made with Si transistors and SiC diodes.
Mitsubishi Electric's large-capacity, all-SiC power modules are expected to help save power as well as lower the size and weight of equipment used in high power trains including Japan's Shinkansen.
Railcar traction inverter with all-SiC power modules
SiC application range
The new traction inverter system's switching loss is approximately 55% less than Mitsubishi Electric's conventional inverter system incorporating IGBT power modules. The new system also increases regenerated energy through the use of regenerative brakes in all speed ranges. Thanks to these solutions, total energy consumption of railcar systems, including their motors, is reduced by about 30% compared to conventional systems.
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).
Main specifications of new traction inverter system
Input voltage: 1,500V DC
Main circuit system: Two-level PWM inverter with regenerative brakes
Control system: Four traction motors with 180kW, parallel control
Cooling system: Self-cooling