Bombardier, Artemis Intelligent Power and Ricardo are collaborating on a research project to create a regenerative braking system suitable for diesel-powered multiple units.
Commencing in the next five months, the three partners will work together on the Digital Displacement Rail Transmission with Flywheel Energy Storage Project, with some funding coming from the UK government, which will combine the Artemis digital displacement hydraulic pump/motor with Ricardo’s Kinergy flywheel energy storage system. Bombardier will ensure a smooth integration of the systems.
Regenerative braking has been a relatively common feature of electric traction, where current is returned to the third rail or overhead line. With DMUs, a self-contained onboard energy storage device is required, in this case the flywheel. Although this is new technology within the rail industry, it has been used in the motor racing industry for quite a while, with the stored energy being used to give cars a boost in power when required.
The system can be tailored to suit a number of operating options, including alteration of the engine demand to enable it to operate closer to the optimum brake specific fuel consumption, resulting in reductions in both fuel and carbon dioxide emissions.
It is estimated that savings of between 10 per cent and 20 per cent can be made by installing the system on DMUs.
Initially the development programme will see the system coupled to a Bombardier supplied wheelset, which Artemus will test on its dynamometer rig in Scotland.
If all goes to plan, it is envisaged that testing will then take place on an operational DMU.