All-SiC Power Modules on Shinkansen Bullet Trains

June 30, 2015 by Jeff Shepard

Mitsubishi Electric Corporation announced that it has completed the installation of, and begun testing, railcar traction converter/inverter systems with all-silicon carbide (SiC) power modules on N700 Shinkansen bullet trains for Central Japan Railway Company (JR-Central). These are the first 3.3kV, 1500A traction systems to be installed on a high-speed train line, according to the company's own research.

Mitsubishi Electric has been working to downsize its traction system for Shinkansen bullet trains. The use of SiC power modules reduces the size and weight of its new converter/inverter system by approximately 55% and 35%, respectively, compared to existing systems. The weight of the traction motor, including this system, is reduced by approximately 15%.

The power modules were developed with support from the New Energy and Industrial Technology Development Organization of Japan. Specifications of main circuit include: Input voltage of 2,500 Vac; Main circuit system: Large-capacity all-SiC power modules ,Three-level pwm inverter with regenerative brakes; Control system: Four traction motors with 305kW, parallel control; Cooling system: Self-cooled.

Mitsubishi previously announced a traction inverter made with all-SiC installed in a 1000 series urban train operated by Odakyu Electric Railway Co., Ltd. in Japan, had been verified to achieve an approximate 40-percent savings in power consumption compared to a train using conventional circuitry. The traction inverter, which is rated for 1,500Vdc catenaries, was tested over a four-month period.