New Motor-Assisted Hybrid Power System for Trains Reduces Emissions and Costs

Hokkaido Railway Co. (JR Hokkaido) announced on October 23, 2007, that it has developed a system that directly transmits power from both a diesel engine and an electrical motor/generator to a train's wheels through the first "active-shift" transmission of its kind in the world. The Motor-Assisted (MA) Hybrid Traction System, developed in collaboration with Hitachi Nico Transmission Co., achieves better tractive performance with a lower-powered engine compared to a conventional diesel-powered train, and it reduces fuel consumption by 15 to 20 percent, resulting in a corresponding reduction in carbon dioxide emissions.

The battery and electrical converter/inverter are smaller than in a conventional series hybrid system, because the electric motor only provides assist power. In contrast, in a series hybrid system, power from a diesel engine is converted into electricity via a generator, and then provided to an electrical motor that drives the train's wheels.

The MA hybrid system is also smaller and lighter--which cuts the cost of the battery, converter/inverter, and other gears by more than half--and it can be used on existing diesel trains with some modification.

JR Hokkaido carried out test runs of the new system on commercial rail lines from November 2007 through January 2008, and considers it the next-generation system for diesel trains. The system can solve the conventional trade-off between improving tractive performance on one hand and reducing energy consumption and environmental impacts on the other.

http://www.japanrail.com/pdf/news/ITT_technical_details.pdf
- World's First Hybrid Rail Car Developed (Related JFS article)
http://www.japanfs.org/db/278-e

Posted: 2008/03/12 03:37:18 PM