Page 37 - 360.revista de Alta Velocidad - Nº 5

Technological, economic and sociological factors on the maximum design speed of high speed trains

Figure 1 maximum speed of passenger trains in the last 40 years ,*concept study
experimental =technical modified or prototype vehicles
commercial = vehicles are used in daily operation
Even though the record runs of experimental vehicles in Figure 1 each document a certain
status of feasibility, which is still to come for the Hyperloop idea, their relevance for every-
daypurposes is actually limited. The TGV world record for instance was conducted on a brand
new high speed line exploiting downhill segments with increased catenary tension and voltage,
the test vehicle was assembled with additional powered axles, larger wheels and deployed
aerodynamic improvements. Since these circumstances cannot be transferred to regular
operation, an interesting question in consideration of the summary in Figure 1 and in competition
to the Hyperloop and the MAGLEV concept still remains unanswered, namely:
What is a reasonable upper speed limit for high speed wheel-rail systems in daily operation?
This question was adopted to be elaborated within the project to be introduced in the following
section.

2. DLR’s Next Generation Train Project

In 2007, DLR initiated a long term research project on a future railway vehicle called Next
Generation Train (NGT). Eight high level objectives were specified:
• Increase in the permitted speed in daily operation to 400 km/h and additionally explore the
velocity range up to 600 km/h
• Halving the specific energy demand compared to the ICE 3 at 300 km/h
• Noise reduction

• Increase in comfort
• Improvement in vehicle safety

• Improved wear behaviour and life cycle costs
• Cost-efficient construction using modulisation and system integration
• Improvement in efficiency of development and approval processes

International Congress on High-speed Rail: Technologies and Long Term Impacts - Ciudad Real (Spain) - 25th anniversary Madrid-Sevilla corridor 35