50 Years of Progress in Railway Technology François Lacôte

Feature Evolution of Railway Technology

(which are still largely to come) of pendulum techniques to permit faster Introduction electronics and digital techniques on speeds on curves. railway engineering. Finally, I will touch SNCF was the first European rail operator In the 1960s, before he became President on rail freight, which has not yet taken to research this field when it ran a series of SNCF (and subsequently President of advantage of the technological changes of tests in the early 1960s on carriages UIC), Louis Armand said, ‘The railway will in Europe. using natural tilting (swing around centre be the mode of transport for the 21st of gravity) and controlled tilting. It came ’ century if it survives the 20th. We have High Speed—from Diversity to to the conclusion that the potential gain now turned the corner into the 21st a European Standard in speed on conventional lines was century and rail transport in Europe is significant with controlled tilting but that perhaps more alive than ever. Constant quest for higher speed 1960s technology could not provide The railway’s history over the last 50 years Since the early 1950s, it has been clear in sufficiently accurate and reliable control has been punctuated by major Europe that increased train speed, to deliver the required ride quality. As a technological changes and this article particularly on passenger trains, is crucial result, SNCF decided to opt for high speed reviews the highlights and shows how the to rail transport’s competitiveness. The on new lines, requiring higher changes were serious gambles in railways were forced to react as the infrastructure investment but delivering preparing for the 21st century. automobile advanced in tandem with the much greater timesavings. The leap in the popularity of high-speed growth of the motorway network to offer Italy was the second European country to trains (250–300 km/h) played a key role significant gains in time and comfort. In attempt the tilting technique and in this evolution, which is both irreversible 1955, SNCF signalled its determination to produced a prototype that was well ahead and fundamental to passenger transport develop faster trains when it set a speed of its time but was to remain restricted to in Europe. Much of this article is about record of 331 km/h with an Alsthom-built two experimental trains in Italy and Spain. high speed and there are two information locomotive. However, at this time, there Paradoxically, the opening of the new boxes on the evolution of high speed in seemed to be two possible ways Rome–Florence line in 1988 (almost 15 Germany, and on the development of forward—using the current infrastructure years after the prototype) saw Europe’s first Italy’s famous Pendolino technology that or building new infrastructure. true tilting train based on Fiat’s design, has now conquered most of Europe. while Fiat in the meantime had become Due to its major role in Europe’s progress Choosing between old and new Alstom Ferroviaria. in rail transport, I will discuss changes in lines or slow maturation of tilting However, we should not forget electrical power techniques, traction and trains developments in England during the same signalling. Part of this article examines The first idea that enters a railway period. In the late 1970s, British Rail the design and construction of carriage engineer’s head when wanting to increase produced the prototype Advanced bodies and some pages cover the impact train speed is to introduce tilting or Passenger Train (APT) with tilting action. Like the Italian Pendolino, it was designed to travel at speeds of up to 250 km/h on the East Coast main line. Unlike the Pendolino, the APT was articulated and required extremely bold technological solutions (like hollow axles to allow hydrokinetic braking by injecting ultra- pure oil into the axles). The APT engineers were perhaps too far ahead of their time and the new technologies encountered many problems, so the APT never went beyond the prototype stage. The UK had to wait until the late 1990s for the delivery of Alstom and Fiat Ferroviaria tilting trains Artist’s impression of high speed in Europe (Alstom Transport) for Virgin West Coast Trains Ltd., operating

out of London Euston on the West Coast main line. Finally, the Spanish company Talgo- Transtech has perfected the Talgo XXI pendulum train featuring a natural tilting action, which although it does not allow as great a speed increase as controlled tilting, does offer simplicity.

High speed on new lines While not forgetting JNR and the opening of the Tokaido Shinkansen in 1964, SNCF was the originator of the modern high- speed rail system in Europe. Although SNCF had put tilting techniques on hold, unlike Germany and Japan who were both looking at development of magnetic Third-generation TGV Duplex (Alstom Transport) levitation systems, SNCF still believed that the scope of this article, I will just mention improvements in speed, comfort, capacity the speed potential of adhesion-based the main milestones: and economy, the basic design of the three wheel and rail systems above 300 km/h • 1972—TGV001 prototype exceeds TGV generations (articulation, was largely unexploited. In the mid- 300 km/h in first year of testing concentrated traction, lightweight and 1960s, it started the C03 research • February 1981—First-generation full- stable bogies, on-body traction motors) programme to establish the basic production trainset sets world rail has remained remarkably unchanged. parameters of a new high-speed railway speed record of 380 km/h system with highly optimized catenary, • September 1981—First-generation Future of high speed in Europe signalling, operations, rolling stock, etc., TGV SudEst enters commercial service High-speed rail transport is now reaching as outlined below: at 260 km/h rising to 270 km/h in maturity in Europe and it is the technology • Specialist high gradient line (35‰) 1982 that has been chosen for Europe’s high- • On-board signalling with attendant • 1989—Second-generation TGV speed transport network—no practical disappearance of trackside signalling Atlantique enters commercial service application has been found for magnetic • Articulated multiple units with at 300 km/h with three-phase traction levitation. Far from competing, the adhesion focused on motor units at the using synchronous motors, pneumatic technologies of high speed on new front and back and lightweight, highly suspension, high-power disk brakes, dedicated lines and tilt trains on stable bogies and on-board computer train conventional lines have been combined command and control systems to produce high-speed tilting trains like This was in sharp contrast to other • 1990—TGV Atlantique sets world rail the tilting TGV tested in France in 1999 countries like Germany and Italy, which speed record of 515.3 km/h on 18 and 2000 and now in use on the Paris– were introducing new lines based on more May 1990 Toulouse and Paris–Brittany services. traditional concepts, particularly low- • 1994—Eurostar links London, Brussels (Italian Railways (FS) has similar projects.) gradient mixed-traffic lines. and Thalys links Paris, Brussels, Although the concept of high-speed Cologne and Amsterdam dedicated lines has gained currency in French TGV • 1997—Third-generation TGV Duplex Europe wherever passenger traffic justifies The French TGV has enjoyed exceptional with high seating capacity enters its use, the mixed passenger/freight line growth in France over the last 20 years service as culmination of speed, concept still finds applications on the and its engineering success is largely due comfort and economy Lyons–Turin transalpine line and the to an exceptional partnership between Perpignan–Barcelona line across the SNCF and rolling stock manufacturers, Although advances in the technologies of Pyrenees. especially Alstom. traction, computer systems, structural Europe’s entire high-speed rail system is Since the whole story extends far beyond alloys, etc., have brought constant now being standardized following a

26 Japan Railway & Transport Review 27 • June 2001 Copyright © 2001 EJRCF. All rights reserved. decision by the European Community and line equipment. Most other countries The appearance of the first French TGV the technical specifications for in Europe chose this route. Nord line caused an interesting interoperability (TSI) cover all system development known as 2 x 25 kV. This components, including infrastructure, In the late 1950s, the limitations of DC development uses a dual power supply signalling, rolling stock, operations, etc. electrification prompted SNCF to explore via a positive-phase 25 kV overhead Clearly, a lot of ground has been covered a completely new but considerable catenary and a negative-phase 25 kV in 30 years! technological gamble—high voltages feeder with auto-transformers at regular (25 kV) at the same frequency (50 Hz) as intervals along the line to earth the rail Changes in Power Supply the national electricity grid. Engineers like potential. This saves on substations and Technologies Armand and Fernand Nouvion realized reduces Joule losses. It also cuts that such as system would have the great electromagnetic interference in the Europe’s railways inherited electrification advantage of needing fewer substations environment because the opposite-phase systems designed at the beginning of the and produce savings in catenary catenary and feeder largely cancel out last century when two major trends equipment. But this was offset by the each other. dominated the choice of technology: increased complexity of the locomotives Thanks to the development of power • Simplicity and economy while requiring on-board power transformation. electronics, this system won the day in permitting use of commutator motor Various schemes were tested including Europe and has become the standard for The choice was for high voltage (15 power-conversion generators powering Europe’s high-speed railway network. The kV) with alternating current (for easy either commutator motors or induction original 15 kV 16 2/3 Hz system now only stepping down through a transformer) motors, and mercury-arc rectifiers for remains on old conventional lines that but at a very low frequency (16 2/3 commutator motors. would be too expensive to convert. Hz) so as not to overburden the motor The new AC electrification technique commutator. Germany, Switzerland, owes its success to the very rapid arrival Austria and Sweden chose this route. of power rectifiers (diodes and then The Electronic Revolution • Simple power conversion on-board thyristors) enabling use of increasingly the locomotive simple electrical on-board systems. With few exceptions, electric traction The choice was for low voltage (1.5 The 25 kV, 50 Hz AC system soon spread began in most countries by using the or 3 kV) direct current, which had the rapidly throughout Europe to become the commutator motor. In Europe, this motor disadvantage of complex and heavy standard for modern electrical traction. was powered either by variable DC voltage using an electromechanical device, or in Germany with variable (15 kV, 16 2/3 Hz) AC voltage. In all configurations, the power conversion system (electromechanical converter and commutator motor) was limited by the motor commutation capacity (especially at 16 2/3 Hz) and by the complexity and vulnerability of the power converters. This led railway engineers to improve the traction systems by two methods: • Replacing electromechanical converters with solid-state converters • Replacing commutator motor with three-phase motor

The first method bore fruit in the early 1970s with the appearance of diodes and Astride asynchronous drive electric locomotive (Alstom Transport) power thyristors. Locomotives and EMUs

were soon running with mixed (diode/ thyristors and was complex, large, information with less risk of interference thyristor) rectifier bridges for AC voltage, expensive and not very reliable. To integrate Europe’s diverse signalling and DC-voltage thyristor current choppers Happily—perhaps miraculously—the systems, the EC is financing development for DC voltage. These techniques also appearance of GTO thyristors of the European Rail Transport simplified design of multi-voltage simplified the converter and Germany Management System (ERTMS), a unified locomotives to run on different European changed the design of its ICE 1 motor command and control system for rail networks with different power supply units to this voltage inverter. SNCF traffic. The fully digital secure system systems. This first electronic revolution adopted the new technology in its transfers data from the ground to on-board enabled production of traction equipment BB36000 Astride locomotives. by using GSM radio. The train calculates that was more powerful, more reliable and its location and safe headway and sends above all cheaper to maintain than In conclusion, we must not forget the this information back to the ground. previous generations. Typical examples arrival of the IGBT, which is more reliable Three trials are in progress in Germany, of these locomotives are the Alstom-built and has a simpler chopping function than Italy and France to test the compatibility BB15000, BB7200 and BB22200, which the GTO thyristor. It has brought compact, of products developed by the national are more powerful (4400 instead of simple and reliable power converters. manufacturers and rail operators. 3200 kW), twice as reliable and less costly The advent of voltage-inverter-based to maintain than their predecessors, and asynchronous traction has reduced the the first-generation TGV SudEst. equipment mass to such an extent that we Carriage Structures The second method of replacing the can now build trains—particularly commutator motor with a three-phase EMUs— that were completely Although early locomotives were built of motor was the second electronic unimaginable just a few years ago. steel, the rolling stock was largely a metal revolution based on the arrival of gate The last component in electrical traction chassis with wooden superstructure. A turn-off (GTO) thyristors and today’s that still constrains railway engineers is number of serious fatal accidents in the insulated gate bipolar transistors (IGBTs). the bulky and heavy 15 kV, 16 2/3 Hz early 20th century convinced everyone of These developments were undertaken in transformer. It is a good bet that the third the need to use metal for all rolling stock. the early 1980s with two competing revolution in electrical traction will High-grade special steels are now technical solutions: involve this component. widespread in Europe and progress in • In France, the commutator motor was coatings means that today’s locomotives replaced by the simple self-exciting and carriages are much more resistant to synchronous three-phase motor, ERTMS in Europe fatigue cracking and corrosion, etc., than retaining the simple thyristor current 30 years ago. We have now moved from inverter. The ‘universal’ BB26000 Right from the first days of railways, a general overhaul at every 6 to 8 years locomotives were built on these Europe’s signalling systems developed to overhauling at every 15 to 18 years, or design principles (high power for completely independently. The result is halfway through the design life. passenger trains, and high start-up a real kaleidoscope of systems, making However, unlike North America and torque for freight trains). Most cross-border operations very difficult. Japan, stainless-steel construction is still importantly, the second-generation Some major trends are emerging from this not widespread in European passenger dual-voltage TGVs used this principle great diversity of systems: carriages. Where it is used, improvements to provide 4400 kW in a mass of only • More complex systems to transmit in welding techniques such as seam 68 tonnes. (The four-voltage Thalys data on location and speed to moving welding instead of spot welding have uses the same design too.) trains greatly improved mechanical strength. • Other European countries chose the • Shift from ground to on-board Introduction of welding robots has asynchronous motor powered by a processing of information on location promoted more use of aluminium alloys voltage inverter with conventional and speed in carriages, especially carriages of high- thyristors. Notable examples are • Disappearance of analog systems, such speed trains (ICE, TGV Duplex), where Germany’s Class E120 locomotives as first-generation German LZB and light weight and good corrosion resistance and the early ICE 1. Although the French TVM on high-speed lines, in are particularly important. asynchronous motor is very simple, favour of less-costly but more complex However, aluminium alloys have vastly the converter used natural turn-off digital techniques providing more inferior plastic-deformation and energy-

High Speed in Germany of the first high-speed lines and 60 ICE 1 trainsets points for interior fittings, air-spring bogies Starting in 1972, the wheel-on-rail research marked the completion of the first stage of to improve ride quality and decouple programme of the German Federal Ministry Germany’s high-speed rail system. structure-born noise of Research and Technology was devoted The 60 first-generation ICE 1s were based on • Updated maintenance concept initially to an in-depth study of the the following design concepts: • Weight reduction of at least 5 tonnes per fundamentals of railway engineering and • Maximum design speed of 280 km/h trailer car compared to ICE 1 adopted a unique, systematic approach. All • Block train formation with up to14 trailer areas of railway technology were investigated carriages The new high-speed line between Cologne and in an attempt to understand the development • More comfortable than IC system Rhine/Main is the most important project in potential for a high-speed rail (HSR) system • Approved for operation on Austrian (ÖBB) the DB AG network at this time, shortening and to determine its technical and economic and Swiss (CFF/SBB/FFS) lines the distance between Cologne and Frankfurt limits. Rolling stock was a focal point of this • Platform heights of 76 cm and 55 cm from 222 km through the Rhine Valley to 177 programme. In addition to creation of design km. About 130 km of the route will be covered tools, research centred on development of Since German reunification, the high-speed line at speeds of 300 km/h, reducing the present 2 carriage components and systems. Finally, in linking Hannover and Berlin (264 km) is being hour and 15 minute journey to less than 1 hour. the early 1980s, preparatory steps were taken rebuilt over some 170 km to permit operation The line is scheduled to enter revenue service towards putting a high-speed test and of 250 km/h ICEs. A further 60 km is being in 2002. International high-speed trains on demonstration train on the tracks–the ICE/V– upgraded for 200 km/h. Regular service started the route will be joined by ICE 3 multiple-unit that integrated the best development results. in May 1998 with 44 ICE 2s on the routes trains, representing another new development. This first ICE/V was operational by late 1985 between Berlin and Cologne and Berlin and Ongoing development of ICE trains is based and completed a programme of Frankfurt. Traffic studies in the expanded high- on design requirements stemming from comprehensive tests and demonstrations in the speed railway network showed that short expansion of German high-speed routes and following 3 years. Then, in May 1988, an trainsets improve loading factors on some routes the European high-speed network. The unmodified ICE/V set a railway speed record while reducing the required number of vehicles. demands with the greatest impact on ICE of 406.9 km/h. Subsequently, the ICE/V As a consequence, the ICE 2 development design are greater tractive power for a provided the basis for the 1988 decision to specifications were as follows: maximum running speed of 330 km/h, a build a production series of ICEs for operation • Half-train configuration with coupling of 1 maximum grade of 40‰, and a maximum on Deutsche Bahn’s (DB AG) new high-speed power car + 6 trailer cars + 1 driving trailer, static axle load of 17 tonnes. These demands lines. and extended train configuration with and continued progress in lightweight carriage High-speed ICE 1 trains entered revenue coupling of 1 power car + up to 14 trailer construction focused attention on the EMU service on 2 June 1991 and immediately took cars + 1 power car. concept with the result that the new ICE 3 is a the lead from other transport modes. ICE trains • Automatic coupler at each end of train for true EMU configuration. The first scheduled are not only DB AG’s fastest trains, they are coupling two half trains ICE 3 service started with EXPO 2000 in also the most popular because of their speed, • Uniform carbody shell with identical Hannover and will total over 200 units when punctuality and comfort. The commissioning window spacing and defined fastening in full service.

delivered to Spanish National Railways (RENFE). Thanks to the positive experience gained from these trains, in 1985, FS ordered fifteen ETR 450 tilting trains consisting of 9 carriages each, with electric traction and a hydraulic tilting system. The ETR 450 entered commercial revenue service in 1988 on the Milan–Rome line immediately revealing its advantages in terms of comfort and a huge drop of some 22% in travel times. The distributed power configuration keeps the axle load low (about 13 tonnes) thus reducing the force of the wheel on the rail despite the speed increase. Thanks to its success in Italy, the Pendolino soon came to the attention of several other European railways and in 1990, DB AG starting operating a fleet of 20 tilting VT 610 railcars to handle fast regional traffic on non- electrified lines in the Nuremberg area. These trains consisted of two carriages with the Pendolino tilting technology and had a maximum speed of 160 km/h. They covered a total of 30 million km up to November 2000. The time reduction on the Nuremberg–Hof line amounted to 23%. Italian Railway’s ETR460, basis for tilting trains in Europe (Alstom Transport) Italian Railways’ ETR 460 was the first third- Tilting Trains in Italy and comfort with no need to change the track generation Pendolino with all the tilting The tilting principle enables the carriage geometry and layout. equipment mounted under the carriage floor. body to lean in on curves, achieving the The initial tests on tilting-body technology The electrical traction features 9 MW of same effect as traditional canting. With a were carried out by Fiat Ferroviaria (now distributed power in 9 carriages and includes a tilting train, it is possible to travel in complete Alstom Ferroviaria) in the late 1960s in GTO-chopper-inverter unit and asynchronous safety with a non-compensated lateral collaboration with FS. The results using a motors. Ten trainsets started revenue service in acceleration at bogie level of 2 m/s2. tilting seat installed on an ALn 668 railcar were May 1995 and have covered more than 11 million Combined with the track cant angle, the so encouraging that it was decided to build km by November 2000. body can be inclined up to 8° reducing the the first YO16 tilting railcar, which soon Several tilting trains designs have evolved non-compensated lateral acceleration at became nicknamed the Pendolino. from the ETR 460 and 65% of the active passenger level to just 0.65 m/s2, well within In 1974, after extensive testing, FS ordered the tilting trainsets in operation or under the comfort zone of 0.8 to 1.2 m/s2. This first prototype tilting EMU consisting of four construction in Europe today have tilting allows a 35% increase in speed on curves carriages. The resultant ETR 401 entered devices designed and manufactured by compared to conventional trains in full safety service in 1976. A similar prototype was Alstom Ferroviaria.

absorption characteristics compared to subject of a European standard. This Digital Technologies and steel for dimensionally equivalent unexpected result is a positive effect of Railways structures. This weakness of light alloys the decision to move to light alloys for has led SNCF, in partnership with Alstom, third generation TGVs! The digital revolution is having a profound to begin R&D into passive and controlled Against this panorama of widespread metal impact on all areas of rail technology. deformation so that the decision to use construction, what should we think about new Design has moved from mainly light alloys for the TGV Duplex does not materials like composites? These materials experimental techniques to more result in reduced passenger safety. are commonly used in other industries, but modelling and prediction through Interestingly, these developments have they are still rare in air, sea or land vehicles simulation. Paradoxically, simulation spread beyond the TGV Duplex and despite their many interesting qualities. R&D shows its limits in the capacity of application of modern structural design is continuing in Europe but application in engineers to use good judgement both in in major deformations (crashworthiness) a complete rail vehicle is only foreseeable formulating the model and interpreting the has spread throughout Europe as the in the medium term. results—how many errors have almost

30 Japan Railway & Transport Review 27 • June 2001 Copyright © 2001 EJRCF. All rights reserved. been committed through overhasty use of suffered significant losses of freight market not progressed as much as the passenger a computer model? share over many years, but they are still sector. In Europe, this means that instead of alive. However, new concerns over the Many European politicians and the dispensing with experimental tests, environmental and health burdens of general public now realize that rail’s modelling is used to improve test heavy truck traffic are forcing Europeans speed, convenience and intrinsic preparation and understanding. to realize the importance of railways in environmental friendliness make it the Consequently, we are witnessing a freight traffic. At the same time, the preferred transport mode for this new dovetailing of modelling and testing, transfer of passenger traffic to dedicated century. But to achieve their full potential, which is indispensable but extremely high-speed networks is freeing up capacity Europe’s railways need the backing of costly. on conventional lines for freight. determined politicians and creative Electronics and information technology Developments are under way, both dedicated railway engineers and will play an increasing part in real-time directly at the European level and through managers. I train monitoring and operations control. partnerships between networks like SNCF The early imperfect on-board electronics and DB AG to produce a new on-board in the TGV Atlantique and ICE 1 have braking system for freight trains—UIC matured to form the ‘nervous system’ of brake technology is 150 years old—that increasingly ‘intelligent’ trains. As part of will greatly enhance the performance of this development, extraordinary progress rail freight transport. The objective is to has been made in using digital techniques achieve a performance leap equivalent to to manage adhesion (the Achilles heel of that already made for passengers and railways compared to other transport create a true European rail freight network methods) during braking, etc. offering much more productivity.

Rail Freight––The Poor Conclusion Relation

No article on the progress of rail The last 50 years, and especially the last technology in Europe would be complete 20 years, have seen railway technologies without mentioning the fact that although move much further than other transport rail freight has benefited from modes. The progress in high-speed considerable progress in traction, it has technologies is such that the European not experienced the depth of change seen high-speed rail network is increasing its in high-speed and tilting trains. impact on Europe every year, but the The great opportunity for automatic network is still hobbled by diverse coupling and traction that all European electrical power and signalling systems. railways were committed to in the mid- Standardization and unification have 1970s and which had been in preparation begun at last but the fruits will be some for many years was missed because of an time in coming. inadequate return on investment. The rail freight sector faces relentless The European rail network—which does competition from road transport and has not offer the same capabilities as the North American freight networks in terms of axle François Lacôte load, clearance profile, and length of sidings or turnouts—has barely changed Mr Lacôte is Director and Senior Consultant of ALSTOM Transport. He graduated in engineering from Ecole Polytechnique and Ecole Nationale des Ponts et Chaussées and joined SNCF in 1974. at all despite the impact of fierce He held various senior posts in rolling stock at SNCF and was in charge of development of the French competition from road transport. This has TGV. He was Scientific and Technical Advisor to the SNCF Chairman before assuming his present led the railways to cost cutting and post. The French government has conferred the chevalier de la Légion d’honneur on him. insufficient margins for freight investment. As a result, European railways have