Hybrid trials Hybrid rail technology is the energy-saving combination of a conventional diesel plus electric drive system.

TU pioneered the use of diesel EU Stage IIIB compliant. later use. The recovery of kinetic energy in engines in rail over The MTU hybrid PowerPack combines the braking mode (regenerative braking) is M 90 years ago. Among the most benefits of a conventional system with an extremely energy and cost-efficient in stop- prestigious early projects with electric propulsion module, an energy storage and-go situations on local public transport lines Maybach engines was the Fliegender system and an outstanding propulsion control where there are a large number of stops and Hamburger or ‘Hamburg Flyer’. It was the first system. It provides a sustainable solution, also inclined sections on ‘hilly’ terrain. streamlined train in the world to go into due to its adaptability to a bi- or trimodal This year, for the first time, MTU performed regular service, travelling between Berlin and propulsion system via a pantograph connection its own tests on a hybrid train. Test runs on Hamburg with a maximum speed of 160km/h to the overhead lines. This versatility Deutsche Bahn’s VT 642 were carried out from May 1933, ushering in the era of high- speed rail travel in Germany. Today, MTU is embracing the opportunities A fuel saving of 15 per cent is a that hybrid technology can offer in terms of efficiency and environmental benefits for fantastic result and means that under the rail industry. optimum conditions, 20 to 25 A conventional MTU railway PowerPack® combines all the individual elements into per cent should be possible. a single functional unit mounted on a Dr Ingo Wintruff, MTU Vice President Propulsion & Power Generation, supporting frame to maximise efficiency. Head of Rail, Mining, Oil & Gas Business As a turnkey supplier, MTU is responsible for all elements of the drive system, contributes greatly to the residual value of in the first quarter of 2015 on the Stauden including the , after-treatment, equipped with these new systems. railway line in Germany, a stretch of track that (diesel-electric, diesel-mechanical, The fundamental idea of hybrid rail is approximately 26km long. or diesel-hydraulic), auxiliaries and cooling. technology is that the kinetic energy initially During the tests, fuel consumption was MTU has already delivered more than generated by the diesel engine is recovered via shown to be reduced by more than 15 per cent 6,000 of its PowerPacks to the rail industry, an operating as an electric brake compared to straightforward diesel mode. This of which approximately 1,000 units are and chemically ‘stored’ in a powerful battery for was achieved even though the track does not

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consumption, the huge savings potential repowered vehicles. In addition, various engines becomes evident. Dr Wintruff was present are available for hybrid shunter locomotives. during one of the test runs and was visibly With its wide experience as a system impressed by how mature the technology solution supplier and after successful testing, actually is. MTU is now moving on to the next stage: The The hybrid PowerPack is the result of five goal is for MTU hybrid PowerPacks to achieve a years of pioneering work by MTU. In the firm foothold in the rail market. beginning, the focus was on the development wof the crankshaft starter-generator, the Author: Rolf Behrens is a member of the MTU team in Friedrichshafen. battery and the convertor, with integration of all systems into a PowerPack. In 2012, a railcar in Deutsche Bahn’s (DB) fleet

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Hybrid train trials 9 1 2

3 POWERPACK COMPONENTS 1 Diesel engine 8 2 E-motor/generator 5 was repowered 3 Transmission using two hybrid drives. DB 4 SCR catalytic converter subsequently tested the train in 5 AdBlue® tank provide the order to prove it for traffic certification. 6 Li-Ion battery ideal profile for During this year’s tests, the MTU engineers 7 Drive controller regenerative braking. succeeded in completing a test programme 8 System control unit Noise levels from the train covering over 2,300km in just six weeks. In 9 Onboard power supply when in motion were reduced by a clearly doing so, they worked through some 70 noticeable five decibels. An even greater different scenarios which they had previously reduction in noise was achieved when the train computer simulated, in order to determine how was stationary. In a station, the train’s sound the system responds to different conditions and level drops by a full 21 decibels, as the diesel how it can be operated with maximum engine is shut down and ancillary loads run on efficiency. The ‘live’ tests also confirmed that the batteries. the computer simulations had predicted the “These test runs represent a milestone in this real results very accurately. project as a whole,” says Dr Ingo Wintruff, MTU At the heart of all current MTU PowerPacks are Vice President Propulsion & Power Generation, diesel engines equipped with SCR technology Head of Rail, Mining, Oil & Gas Business. “A fuel for reducing NOx emissions that comply with All individual drive components of saving of 15 per cent is a fantastic result and emissions legislation EU Stage IIIB. For the MTU PowerPack are integrated on a common base frame to form a means that under optimum conditions, 20 to 25 underfloor installation, the product portfolio single compact unit. The batteries per cent should be possible.” Considering that includes Series 1800 (428-530hp / 315-390kW) of the railcar which was tested are around 90 per cent of the total costs for rail as well as Series 1600 (768-952hp / 565-700kW) mounted on the vehicle’s roof. drive systems are attributable to fuel diesel engines, which can be used in new and

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