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- ~ -,,:.r-- ~ · PT.29: TIIE AUS'FRALIAN VFT PROJECT THE EVOLUTION OF ELECTRIC RAILWAYS In the last episode in this series, we look at recent developments in fast trains overseas. We then conclude with a discussion of the Very Fast Train proposed to link Sydney and Melbourne, and later other capital cities and population centres. By BRYAN MAHER As might be expected from their considerable past experience with electric traction, the Swedes are working with experimental high speed trains. They consider new dedicated tracks too expensive in their crowded country. Therefore, in August 1986, Swedish Railways (SJ) let a contract to ASEA Traction for 20 high-speed trainsets capable of 200km/h on the existing tracks. Each trainset consists of one lightweight Bo-Bo electric locomotive hauling five passenger coaches. Additional coaches can be added when necessary. The rear coach contains a driver's cabin and full console from which the train can be driven when running in the reverse direction. Each train is equipped with a buffet car and carries 288 passengers. The aim is to reduce the present travelling times by 25% on all main lines and recapture the passenger traffic currently lost to road and air travel. To achieve this, consistent running at 200km/h is required. At this speed, the 457km journey from Stockholm to Gothenburg will shrink from the present 4 hours and 5 minutes to a tidy 3 hours. The current traffic is 2,700,000 passengers annually, a figure which is expected to rise to 4,400,000 by mid 1990. This increase will fully occupy the first 20 trainsets delivered. SJ has an option with ASEA for a further 32 similar trainsets, destined for the Stockholm-Malmo, Gothenburg-Malmo and StockholmSundsvall routes. ASEA's experimental train ASEA has based the design on their class Xl 5 experimental mainline train. This has been running on SJ mainlines since 1977, assisting in the development and testing of new motor drive systems, bogies and train controls. The excellent results of SJ's XlO commuter trains running in the cities of Stockholm and Gothenburg and the southern districts of Sweden since 1982 have confirmed much of ASEA's research. AN ARTIST'S IMPRESSION of the Australian VFT streaking through the countryside. We think the artist must have let his/her imagination run riot about the gradient though. Maximum gradients are planned to be 3.5%, not 20% or more as shown in this view. 4 SILICON CHIP Gate-turn-off thyristors (GTOs) and 3-phase variable frequency variable voltage induction traction motors have been a valuable result of this concentrated R&D effort. Add to this new motor control systems, suspension and coupling techniques and we have the great advance in technology now being exported from Sweden to the rest of the world, including Australia. ASEA Brown Boveri are even now developing a more advanced GTO, with the promise of inverters using less semiconductors, at lower cost and weight. 15kV 16.6Hz supply The Swedish fast trains operate from the standard single phase 15kV 16.6Hz overhead voltage. In each locomotive, the main transformer has six secondaries; four of these supply the traction system, one feeds the auxiliaries and the sixth secondary is dedicated to harmonic and power factor control. Each traction secondary winding feeds a 4-quadrant GTO rectifier GERMANY'S VERY FAST ICE (Intercity Experimental) trains held the world speed record until just recently. When they begin full operations, the trains will be fully sealed, so that passengers will not experience uncomfortable pressure variations when passing through tunnels. bridge, the outputs of pairs of bridges being paralleled to form a DC link. Each DC link supplies power to a 4-quadrant GTO DC/AC 3-phase inverter which then drives two of the four 3-phase inductiontype traction motors. Because 4-quadrant controlled GTO bridges are used throughout, full regeneration of power is possible, allowing traction and regenerative braking with the one switchless system. When the driver wishes to slow down or stop, he reduces the frequency of the inverter output. While the induction motors are pulling the train they normally run at about 97% of synchronous speed but when running (under momentum) faster than this sync speed they act as asynchronous alternators, to apply braking to the train. This regenerated power returns via the inverters, the rectifying bridges and the transformer to the whole SJ railway grid. Germany's ICE train Until just recently, the official world rail speed record of 406km/h was held by the German Federal Railways (DB) Inter-City Experimental (ICE) train. Designed with optimised aerodynamics, the new ICE train has improved high speed power and trailing bogies and a total train power of 8.4MW (11,260 hp). Two locomotive designs are being tested, one built by ABB and one by AEG and Siemens. The 114m long train consists of a Bo-Bo electric locomotive at each end, with three passenger coaches carrying a total of 261 passengers. Each 4.2MW loco weighs 78.2 tonnes and passenger coaches weigh 46.6 tonnes, giving a total weight of 296 tonnes for a 5-car train. Though each locomotive is equipped with a lightweight pantograph, MARCH 1990 5 haul the VFT at 330km/h. ABB are building Bo-Bo-Bo locomotives to haul the train from the French Coast through the tunnel and on to London. While in the tunnel the locomotives will run on 25kV 50Hz. Once on English soil, the loco will draw power from the British Rail south line 750V DC 3rd rail current system. The Australian VFT ANOTHER VIEW OF GERMANY'S high speed ICE train. Normally these travel with only the rear locomotive's pantograph in the raised position. This is done to keep drag to an absolute minimum. only the rear loco runs with its pantograph raised, similar to the French TGV described last month. This reduces slipstream drag. A high-voltage cable runs the length of the train to connect both pantographs. Each loco carries a 5.12MVA transformer, GTO rectifiers and a 7.6MVA inverter to supply 3-phase variable voltage variable frequency drive to the four induction type traction motors. To minimise that gremlin of all high-speed trains, unsprung weight, special suspension methods are used for the heavy motors. The locomotive body carries 2/3 of the weight of motors and gear box, the remaining 1/3 of their weight being suspended from the bogie frame. Flexible lateral suspension units perform this mass-juggling miracle which leaves the driven axles to carry little more unsprung weight than the running wheels and axle. Complete with hydraulic dampers to modify vertical and lateral movement, this clever construction results in minimum track stress at very high speed, and a high degree of train rolling stability. Florida's VFT project This American very fast train is proposed to run on a dedicated line 6 SILICON CHIP from Miami on the Atlantic coast to Tampa on the Gulf of Mexico. To avoid formidable civil engineering work, this new line will not cross the Everglades but will detour northwards. From Miami, the train will run through Palm Beach to Orlando, serving the Florida Disneyland, a potential source of considerable passenger patronage. From Orlando, the route will take a south westerly path to Tampa. The total run will be 480km. The Florida trains will consist of a 3.2MW 25kV 60Hz Bo-Bo electric locomotive at each end, with three 1st class and five holiday class passenger coaches and a diner between, giving a capacity of 480 passengers. Eight 3-phase induction motors will propel the train at 240km/h. When the green light is given for construction, ABB will provide the locomotives and rolling stock. English Channel VFT The Trans Manache Link (TML) Company is constructing a pair of tunnels beneath the English Channel to directly link England and Europe by rail. Tunnel users will rent pathways at set times. One user will be the London-Paris very fast train. Between Paris and the coast, the French locomotive will Originally proposed by the eminent Australian scientist Dr Paul Wild, the concept of a very fast train carrying passengers from Sydney Central to Melbourne Princes Street in less than three hours is quite realistic. Consider that by jet plane the trip from city to city takes 1 hour and 15 , minutes flying time plus delays at the terminals and travel by car from city to airport and vice versa. All up, in peak hours, the total travelling time can easily be 3 hours 30 minutes or more. Then there are many people unwilling to travel by plane. And what of freight? The Australian VFT is presently in the advanced design stages, sponsored by a consortium of private industry: BHP, Elders IXL Ltd, Kumagai Gumi Ltd and TNT Australia Ltd. The proposed train will run from Sydney past Mascot airport, to Bowral, Goulburn, Canberra, Cooma, Bombala, Orbost, Bairnsdale, Dandenong and then Melbourne. The system will be entirely double track, of standard gauge, (1435mm), using advanced wheel and rail technology, with electric traction. Estimated to cost $4.8 billion to construct, the project should provide employment for 25,000 Australians in the building of permanent way and civil engineering works, rollingstock, power supply and support facilities. As well as providing SydneyMelbourne travel, the system will give access to Canberra and the Snowy Mountains. Fares are expected to be competitive with air travel and two classes of coach seating arrangements will suit all travellers at a variety of charges. The no- FLORIDA'S FAST TRAIN PROPOSAL looks similar to the French TGV hut if it is given the go-ahead, all locomotives and rolling stock will be supplied by ABB of Sweden. tional design calls for a running time for non stop trains of 2 hours and 56 minutes, with less than 8 minutes longer if two stops are made along the way. Two locomotives The proposed train will probably consist of two 4MW Bo-Bo electric locomotives, one at each end, with six intermediate cars between. On passenger trains, the cars will consist of first and economy class cars, some with food preparation galleys. There will be 80 passengers per first class coach and 98 per economy car. These numbers will be reduced to 64 and 79 respectively in the case of cars incorporating a galley or baggage compartment. The total train is expected to be 210m long and will carry about 400 passengers. Each locomotive is planned to be 20m long, 3.2m wide and 4.4m high, weighing 80 tonnes. Passenger cars will be 6.2m longer than a locomotive, the same width, but 300mm less in height, and weigh 40 tonnes empty. Freight cars will be only 18m long, weighing 80 tonnes. The high train power of at least BMW (10,700 hp) is necessary to accelerate the train to the 360km/h operating speed on the high speed track section. Fast and suburban sections The route may be assumed to consist of three speed sections. Within 20 to 30km of terminal stations (Sydney and Melbourne), the track will parallel existing SRA and VR suburban lines. Here speed will be restricted to within 90 to 200km/h for two reasons: track curvature and power supply. Both the NSW and Victorian Railways use 1500V DC supply for their electric traction and 120V AC for signalling and interlocking systems. When running on parallel tracks in these regions, the VFT will also be powered by the 1500V DC supply but the (approximately) 1 lMW required per train will not be available - hence the restriction in speed. Once clear of suburban areas, the VFT high speed tracks will be powered by high voltage single phase AC. Whether 25kV or 50kV will be used is still to be decided. Between cities, a steady 350 or 360km/h running speed is envisaged. To allow such continuous speed, track curvature will be limited to 7km horizontal and 22km vertical. The track will be BHP headhardened 60kg/m rail on 270kg prestressed concrete sleepers, laid on a heavy ballast bed. In all, 860-900km of electrified double track will be constructed on a 30-metre wide easement, but this will be wider where earthworks, culverts and railway stations are built. With the high power/weight ratio proposed, (8MW/460t or 17.4kW/t), the VFT will be quite capable of racing up 3.5% grades at full speed. Therefore the design philosophy is to run straight up and over hills rather than curve around them. Aerodynamics At a speed of 350km/h, aerodynamic design is paramount. The total resistance to motion of a train must (obviously) be overcome by the locomotive power. On flat track in still air, the motion resistance of any vehicle can be expressed by the standard polynomial equation: MARCH 1990 7 train on the system is using current. Excess power generated by the train during braking can readily be absorbed by the state electricity grids. This facility will not always be available while the VFT is running on 1500V DC within the Sydney and Melbourne suburban areas, as the suburban DC supply is sometimes unreceptive. But regenerative power will also be absorbed by the train's own auxiliary load - adequate for braking at the low suburban speeds. Eddy current brakes AUSTRALIA'S VFT (VERY FAST TRAIN) is currently in the process of an $18.9 million dollar feasibility study. It is being planned to take advantage of the high potential passenger traffic between Sydney, Canberra and Melbourne and will run at speeds of 350km/h. Expected travelling time between Sydney and Melbourne is 3 hours. Resistance = A + Bv + Cv2 + ... where: v = velocity; A = mechanical bearing friction plus the rolling friction of wheel on rail (not a problem using roller bearings). Rolling friction is minimised by using heavy rail rigidly laid; B = that part of rolling resistance which is proportional to velocity, plus the momentum of any air volume carried forward by the train. The first part is a function of weight per axle, while the second part is minimised by streamlining. Bogies, pantographs, coach joins and air intakes of diesel or gas engines all trap air, adding drag. Successful streamlining minimises these factors and rejects the use of diesel or gas propulsion. Electrification using a single pantograph running knuckle-forward, enclosed bogies, flush fitting windows and doors and continuous profile vestibule coach joins are thus mandatory; C = (train aerodynamic frontal area) x (air density) x (frontal, bogie and pantograph air pressure effect + train skin friction). The C term can be reduced to: skin friction, 50%; bogie and undercarriage air drag, 25%; pan- e SILICON CHIP tograph 6% ; airconditioning intakes 6 % ; front end 6 % and rear end 6% Though smaller than A or B, C is vital as it is multiplied by the square of the velocity. At high enough speeds, the air resistance of the train skin can predominate over all other considerations (assuming optimum aerodynamic shape). Skin air resistance can be minimised by smooth construction using unpainted stainless steel, welded, not riveted. Motive power To keep the unsprung mass per axle down to 1.6 tonnes, it will be necessary to body-mount the traction motors and gearboxes. Hollow quill drive shafts will transmit traction and braking forces between motors and driven wheels. Total load per axle will be 20 tonnes. Three phase induction motors will be used for traction. The benefits of high power to weight ratio and rugged, simple, maintenance free rotors make induction motors the top choice. As a bonus, the use of GTOs allows 4-quadrant power transfer, for full regenerative brakes at all times. This electric brake facility will be fully operative even if no other Out on the high speed section of the track, because of the limits on wheel-rail adhesion at high speed, even a combination of electric regenerative brakes and pneumatic disc brakes will be insufficient. The train specification is stringent, calling for an emergency stopping distance of 3500m for a train running down a 3.5% grade at 350km/h! Therefore eddy current brakes will also be used to assist in stopping the train. A controlled current flowing in electromagnets train-mounted close above (but not touching) the rails will produce eddy currents in the rails. This dissipation of energy generated by motion causes a braking effect. Thus, the train will be brought to a stop by a force which does not require wheel-rail adhesion. To ensure compatibility with VR and SRA locomotives should towing of a VFT ever be needed, and to provide a parking brake, a standard air brake and train pipe will also be available. Noise emission There should be no fear of excess noise within the suburbs. The German ICE train at 150km/h is quieter than existing VR and SRA suburban trains at 80km/h. Logistics The proposed Sydney-Melbourne VFT will generate (directly and indirectly) 25,000 jobs for 5 years during construction. At least 32 trainsets will be built in Australia, including 200 passenger cars, 20 freight cars and 64 locomotives. The complete construction will cost $5 billion in today's values. Passenger traffic of 14,000,000 trips, equivalent to 6,600,000 full Sydney-Melbourne journeys, annually is expected. The 900km double track will need 217,000t of steel rails, 3,000,000 sleepers, 9 million tonnes of ballast and 6600t of copper overhead contact wire. All these materials are available from Australian manufacturers. Between 4000 and 8000ha of land will need to be purchased, 50 to 100m wide over 800 kilometres. A total of 326 bridges, totalling 18km are planned, mostly in the Dandenong section. Besides the two terminals, 16 railway stations are proposed to cater for tourists to the Snowy Mountains ski resorts and other intermediate stops. Tunnels will be unavoidable in the city suburban areas, probably 6 in Sydney and up to 10 in the precincts of Melbourne. Frequent trains An average of one SydneyMelbourne non-stop train every 30 minutes is proposed, with one intermediate stopping train per hour. Peak hours will see extra express ANOTHER ARTIST'S IMPRESSION of the Australian VFT running through the countryside. As with the TGV, the VFT will run with just the rear locomotive's pantograph raised. And since the supply voltage will be 25kVAC or 50kVAC, the height of the catenary is likely to be somewhat greater. trains added to the route. The Sydney-Melbourne fare is expected to be approximately $100. The consortium is hoping to start construction within 12 to 18 months. First, the Sydney-Canberra section will be constructed to enable full-speed testing of rolling stock, power and in-train signalling systems. The Canberra-Melbourne leg will commence construction the following year, with the entire railway to be completed by 1996. Feasibility study The first report of a $18,900,000 feasibility study delivered in November 1989 predicted that the VFT would generate $1 billion in ticket and freight charges annually. The report also costed an alternative inland route via Albury. The consortium presently favours the coastal route because it has greater scenic and tourist attraction. On the coastal route, stations are proposed at the following centres: Sydney, Mascot, Campbelltown, Bowral, Goulburn, Canberra, Cooma, Bombala, Orbost, Bairnsdale, Maffra, Traralgon, Moe, W arragul, Dandenong and Melbourne. Inland route stations The inland alternative route proposes stations at Sydney, Mascot, Campbelltown, Bowral, Goulburn, Canberra, Yass, Wagga, Albury, Wangaratta, Benalla, Seymour, Tullamarine and Melbourne. This route is more than 100km shorter than the existing Sydney to Melbourne railway. Perhaps the day of great electric railway progress is indeed dawning in Australia. On this optimistic note we end our series on "The Evolution of Electric Railways". Acknowledgements Special thanks to Dr John Nicolson (technical manager) and Dr Paul Wild (chairman) of VFT Australia; to Lars Persson of ASEA Brown Boveri Traction (Aust). Also to Comeng of Granville and Dandenong, ASEA Journal, ABB Journal, BBC, AEG, SJ (Sweden), DB (Germany), CFF (Switzerland) and Deutsche Eisenbahn Consulting (Frankfurt) for photographs, data and permission to publish. ~ MARCH 1990 9