Maglev Background

Magnetic levitation (maglev) is an innovative transportation technology. It is sometimes said to be the first fundamental innovation in the field of railroad technology since the invention of the railway. A high speed maglev train uses non-contact magnetic levitation, guidance and propulsion systems and has no wheels, axles and transmission. The replacement of mechanical components by wear-free electronics overcomes the technical restrictions of wheel-on-rail technology. Compared with traditional railways, maglev systems have features that could constitute an attractive transportation alternative:

• High speed. Capable of traveling safely at speeds of 250 to 300 miles-per-hour (112m/s to 134m/s) or higher, which is four times the national highway speed limit of 65 mph (30m/s). Maglev could offer a convenient alternative for intercity travelers.

• High safety. Despite high speeds, passengers may be safer than in other transportation systems. The electromagnetically suspended vehicle is wrapped around the guideway and therefore virtually impossible to derail. Elevated guideways ensure that no obstacles can be in the way.

• Less pollution. As maglev is electrically powered, there is no direct air pollution as with airplanes and automobiles. It is easier and more effective to control emissions at the source of electric power generation rather than at many points of consumption. Due to its non-contact technology, there is neither rolling nor engine noise.

• Low energy consumption. With non-contact technology, there is no energy loss due to the wheel-guideway friction. The vehicle weight is lower due to the absence of wheels, axles and engine.

• High capacity. Maglev systems can provide sufficient capacity to accommodate traffic growth. They can help relieve air and highway congestion by diverting a portion of highway trips and by substituting for short air trips.

There are three primary functions in maglev technology: (1) levitation or suspension; (2) propulsion; (3) guidance. Current maglev system design uses magnetic forces to perform all three functions.

Currently there are two principal different designs of suspension systems. One design is called ElectroDynamic Suspension (EDS). The Japan Railway Technical Research Institute’s (RTRI) MLU-series maglev design is an EDS system.

The EDS has onboard magnets that induce current in the guideway sidewalls while the vehicle is moving. Resulting repulsive forces produce inherently stable vehicle support and guidance, because the magnetic repulsion increases as the vehicle/guideway gap (both vertical and lateral) decreases. The magnetized coil running along the track repels the large magnets mounted on the train's undercarriage, allowing the train to levitate between 0.39 and 3.93 inches (1 to 10 cm) above the guideway. However, some form of support is needed for taking off and landing, since the EDS cannot be levitated at speeds lower than 62 mph.

The second design is called ElectroMagnetic Suspension (EMS). The German technology, the Transrapid International (TRI) maglev system, is based on an EMS design, which is an attractive force levitation system. Electronically controlled support magnets are located on both sides along the entire length of the vehicle. Ferromagnetic stator packs are mounted to the underside of the guideway. The electromagnets on the vehicle interact with and are attracted to ferromagnetic rails on the guideway. Electromagnets attached to the train's undercarriage are directed up toward the guideway, which levitates the train about 1/3 inch (1 cm) above the guideway and keeps the train levitated even when it's not moving. The attractive force produces inherently unstable vehicle support because the attractive force increases as the vehicle/guideway gap decreases. An electronic control system is equipped to maintain the vehicle/guideway gap and prevent contact. This involves the complex problems of gap sensing, analog and digital control, and precision construction.

Guidance magnets are located on both sides along the entire length of the vehicle to keep the vehicle laterally stable during travel on the track. Electronic control systems control the clearance (nominally 10 mm). The levitation system uses on-board batteries that are independent of the propulsion system. The vehicle is capable of hovering up to one hour without external energy. While traveling, the on-board batteries are recharged by linear generators integrated into the support magnets.

A synchronous, long stator linear motor is used in the Transrapid maglev system both for propulsion and braking. It functions like a rotating electric motor whose stator is cut open and stretched along under the guideway. Inside the motor windings, alternating current is generating a magnetic traveling field that moves the vehicle without contact. The support magnets in the vehicle function as the excitation portion (rotor). The speed can be continuously regulated by varying the frequency of the alternating current. If the direction of the traveling field is reversed, the motor becomes a generator which brakes the vehicle without any contact.

Figure 1.5 schematically shows that, in accordance with Lenz’s Law, the interaction of the levitation field with the current in the slots of the rail results in propulsion or braking force. During the motion of the magnet along the rail, the linear generator winding of the main pole is coupled with a non-constant flux, which induces a voltage and reloads the on-board batteries. The generation process begins in the range of 15 km/h and equals the losses of the magnetic suspension systems at 90 km/h. The whole energy losses of the vehicle are compensated at a velocity of 110 km/h and the batteries are reloaded. Thus the levitation magnet integrates three tasks: levitation, propulsion and transfer of energy to the vehicle.

The maglev train hovers over a double track guideway. It can be mounted either at-grade or elevated on columns and consists of individual steel or concrete beams.

One major difference between Japanese and German maglev trains is that the Japanese trains use super-cooled, superconducting electromagnets. In the EMS system, which uses standard electromagnets, the coils only conduct electricity when a power supply is present. But the technical requirements for Japanese maglev train are higher than in the case of attractive magnetic forces for which only one side of the system needs to be equipped with electrical wires (the vehicle) for vehicle levitation.

Another difference between the systems is that the Japanese trains levitate nearly 4 inches (10 cm) above the guideway. Compared with German trains, which are levitated only about 1/3 inch (1cm), this great gap will generate high stray magnetic fields. Since the gap is much smaller in the EMS system, the force density is sufficiently high and the power consumption is very low even with ordinary electromagnets. It is not necessary to use superconducting coils. While levitation can be achieved at low speed and even at standstill for an EMS system, maglev trains using EDS system must roll on rubber tires until they reach a lift-off speed of about 62 mph (100 kph).

Maglev Progress

Germany (TRI) has been investigating electromagnetic levitation since 1969, and commissioned the TR02 in 1971. The eighth generation vehicle, the TR08, which operates on 19.6 miles (31.5km) of guideway at the Emsland test track in northwest Germany, is the culmination of nearly 30 years of German maglev development. Control systems regulate levitation and guidance forces to maintain a 1cm (0.4in) gap between the magnets and the iron tracks on the guideway. Some of its precursor prototype vehicles, the TR07 and the TR06, have been tested at the Transrapid Test Facility (TVE) for more than 15 years.

Construction work of the Shanghai Transrapid line began in March 2001. After only 22 months of construction time, the world's first commercially operated Transrapid train made its successful maiden trip on December, 31 2002. On December 29, 2003, the world’s first commercial Transrapid line with a five section train started scheduled operation in Shanghai. The Shanghai maglev system travels on a 30km double-track elevated guideway, connecting LongYang Station in Shanghai to Pudong International Airport. The journey time is under 8 minutes. Regardless of the load and speed, the onboard control system maintains a 10mm gap with a ±2mm tolerance between the vehicle’s support magnets and the guideway’s stators and between the guidance magnets and the steel guide rails. A hybrid girder design is used to combine the low cost of concrete with the precision manufacturing offered by steel. The I-shaped hybrid girder is 25m long, 2.8 wide, 2.2m high and weighs 1.86MN with a reinforced concrete center girder and bolted steel cantilevers. The girders were milled to a precision of 0.2mm.. Engineers evaluated the girder with respect to as many as 14,000 load cases by consideration of the deflection, dynamic strength and thermal expansion. The reinforced concrete support piers are designed to withstand the seismic forces of earthquakes up to 7.5 on the Richter scale. The maximum allowable total deformation of the guideway is 10mm, which can come from the settlements caused by consolidation or creep, by dead load, by cyclic loads from the vehicles or by dynamic loads during operation. "Three-way" bearings are installed between the guideways to allow alignment corrections. The Chinese government intends to link Shanghai to the city of Hangzhou, 193km to the southwest, which would create the world’s first intercity maglev line.

In Germany, starting in 2009, the Transrapid will connect Munich's city center with "Franz-Josef Strauß" Airport. The construction of the Shanghai Transrapid line and the decision on the maglev projects in Germany have given credibility to the innovative rail system. In the U.S., Congress established the Maglev Deployment Program in 1998 as part of the Transportation Equity Act for the 21st Century (TEA-21) with the expressed purpose of building a maglev demonstration project. Six projects are about to be decided on: a 60 kilometer long connection between Baltimore and Washington, a 76 kilometer long airport link in Pittsburgh, two in Southern California, one from Las Vegas to Anaheim, California, and one from Atlanta to Chattanooga, Tennessee.

 

[Source: Huiguang Dai, “Dynamic Behavior of Maglev Vehicle/Guideway System with Control”, Department of Civil Engineering, Case Western Reserve University, August, 2005.]  

 

 

 

Transrapid History

 

 

1934 - 1977: From the idea to the system decision
1978 - 1991: From the test facility to technical readiness for application
1992 - 1999: The first application in Germany is planned
2000 - today: Alternative routes in Germany and abroad
 

 

 

Frequently Asked Questions

 

 

1) Technology:

 

1-1) Are passengers endangered when the vehicle is lowered onto skids in an emergency?

Should the vehicle be lowered onto skids in an emergency or in the case of power failure, this will happen at a very low speed (10 km/h). The vehicle will then coast on the skids until it stops just like a sledge. The landing skids are coated with a special material which provides a coefficient of sliding friction of 0.1 when it gets into contact with a steel sliding surface. The frictional heat produced is dissipated by the vehicle. It suffices to melt any layer of ice, so normal friction conditions and thus optimal deceleration values are achieved. There is no danger of the vehicle catching fire due to the frictional heat produced during landing because on the one hand, the frictional heat is too low and, on the other, non-combustible materials are used in the vehicle.

1-2) Can the superspeed maglev system operate in winter?

The icing of the overhead lines which may interrupt the operation of conventional railroad systems is impossible in the case of the superspeed maglev system because it has neither overhead lines nor power collectors. The propulsion components of the superspeed maglev system are installed in a protected position under the guideway table where neither snow nor ice can gather. Additionally, hardly any snow remains on the guideway even if snowfall is heavy because it is blown away either by constant train operation or (in particular where the guideway is elevated) by the wind. As the distance between the underside of the vehicle and the upper side of the guideway table is 15 cm, the superspeed maglev system can continue operation even if a blanket of snow should "cake together" on the guideway up to this height. In rare case where blankets of snow are higher, snow removers are used.

1-3) Can the Transrapid drive through tunnels?

Because of the flexible route alignment elements, the Transrapid guideway can easily be adjusted to the landscape. Therefore, far less tunnels than for railroad are needed where the terrain is hilly. For example, one third of the newly constructed ICE route between Hannover and Würzburg is through tunnels (60 all in all). The superspeed maglev route would require tunnels only on around 10% of the route. Tunnel cross-sections required for Transrapid and ICE are comparable for the same distances. For example, at a speed of 300 km/h they are 86 m² for the Transrapid double track guideway and 82 m² for modern railroad.

1-4) Do the magnetic fields generated by the Transrapid pose a danger to humans and the environment?

The intensity of the magnetic field generated by Transrapid systems is comparable to the earth's magnetic field and thus far below the magnetic field intensity of usual household appliances. A hair-drier, a toaster or an electrical sewing machine are surrounded by magnetic fields which are much stronger than those occurring in the passenger compartment of the Transrapid. Outside the vehicle the magnetic fields along the route are even much weaker. The electromagnetic fields generated by the long-stator motor and the levitation and guidance system have been measured by Deutsche Bundespost. They are far below the admissible VDE limits. Negative influences on pacemakers or plastic cards (e.g. credit cards) are thus ruled out. This doesn't apply to the Japanese maglev system which cannot be used by persons wearing pacemakers because the magnetic stray fields are more than 1,000 times as strong as those occurring in the Transrapid.

1-5) How does the linear generator function?

The linear generator consists of additional cable windings integrated into the levitation magnets in which current is induced without contact during driving and temporarily stored in the vehicle's onboard batteries. For electromagnetic induction the linear generator uses harmonic waves in the propulsion magnetic field which result from the grooves of the long stator in which the stator cables are installed and the time variation of the magnetic conductibility of the magnetic circuits involved. For energy generation therefore the linear generator doesn't use the useful magnetic field but side effects due to the grooves of the long-stator.

1-6) How is the gap between the magnets and the guideway measured?

Additional inductive gap sensors are integrated in the levitation magnets. They are designed as independent oscillatory circuits generating eddy currents in the stator which in turn have an influence on the primary oscillatory circuit of the sensor. When the gap width changes, the eddy current changes. The deviation of the electrical signals of the oscillatory circuit is evaluated and magnetic regulation units regulate the currents in the magnets adjust the gap width as required.

1-7) What are the components of a long stator motor?

The long stator consists of two components: the stator pack and the cable winding. A single stator pack consists of a certain number of thin ferromagnetic sheets of steel which are glued together and sealed in resin. Such a bundle of laminations is 1,032 mm long, 158 mm wide and about 90 mm high. The three-phase cable winding consists of an aluminum conductor with plastic insulation. The outside diameter is 43 mm, the cross-section of the conductor is 300 mm². For every kilometer of route, a factor of 2.35 of cable winding per phase is required.

1-8) What happens when a fire breaks out in the vehicle?

The materials used in Transrapid vehicles are modern PVC-free materials which are incombustible and hardly heat conducting as well as burn-out and temperature resistant. This means that the superspeed maglev system exceeds aviation safety requirements although the requirements for its operation are much less demanding because the train, being guided by rails, cannot crash nor has it fuel on board or an artificial atmosphere. Moreover, the individual vehicle compartments can be sealed hermetically.

1-9) What happens when the power fails?

When the power from the mains fails during driving, the levitation and guidance system is supplied by means of onboard batteries which are charged without contact during driving. Therefore, the vehicle will use its existing "momentum" to glide to the next stopping area. Should the next stopping area be too far away, the vehicle stops at one of the auxiliary stopping areas provided for the purpose at regulation intervals along the guideway. The vehicle is stopped with the aid of a non-contact eddy current brake which is also supplied from the onboard batteries and brakes the vehicle to a speed of 10 km/h. The vehicle is then lowered onto skids and stops after a few meters. An emergency stop on the open track can be ruled out.

1-10) What happens when two trains meet?

When passing in oncoming traffic or through tunnels at high speeds, the pressure acting on the vehicles is high. Therefore, the passenger compartments of superspeed transport systems must be pressure sealed. The necessary design features (such as pressure sealing, air-conditioning unit design) are known and state of the art. To determine the pressure load on the trains in oncoming traffic and in tunnels, measurements have been taken on a gust measuring wall at the Transrapid Versuchsanlage Emsland (TVE, Transrapid Test Facility Emsland). The results from these measurements and from ICE operation tests have been used to dimension the tunnel cross-sections and the distances between the two tracks of the double-track guideway.

1-11) What is the maximum frequency supplied to the traveling field?

The maximal frequency of the traveling field is 270 Hertz (Hz).

1-12) What is the regulating frequency of the levitation magnets?

The current regulators of the magnetic regulation units change the current in the levitation magnets with a maximal frequency of 100 kHz. Because of the masses and electrical systems involved the natural frequency of the magnetic control circuit is around 30 Hertz to be able to reliably follow the guideway.

1-13) Why are attractive magnetic forces used for levitation instead of repulsive forces?

Repulsive technologies would require the use of permanent magnets or superconductors. The technical requirements for both solutions are higher than in the case of attractive magnetic forces where just one side of the system needs to be equipped (in the case of the Transrapid the moving part, i.e. the vehicle). The system which is especially expensive in the case of repulsive magnetic forces in combination with a long-stator linear motor is gap regulation. Superconductive coils such as those used in the Japanese system require permanent cooling, the levitation forces become sufficiently high only after a certain speed is reached and the great gap of 10 cm generates high magnetic stray fields. An additional disadvantage of permanent magnets is their great weight.
 

 

2) System:

 

2-1) Can mobile phones be used in Transrapid vehicles?
In contrast to the Japanese maglev system, the intensity of the magnetic fields of the Transrapid system is comparable to the earth's magnetic and thus far below the magnetic field intensity of usual household appliances. A hair-drier, a toaster or an electrical sewing machine are surrounded by magnetic fields which are much stronger than those occurring in the passenger compartment of the Transrapid. Outside the vehicle the magnetic fields along the route are even much weaker. The electromagnetic fields generated by the long-stator motor and the levitation and guidance system have been measured by Deutsche Bundespost. They are far below the admissible VDE limits. Negative influences on pacemakers, plastic cards (e.g. credit cards) or mobile phones are thus ruled out.
 

2-2) Can the superspeed maglev system run off the rails?
The vehicle encompasses its guideway, so it cannot run off its rail.
 

2-3) Can the superspeed maglev system used to transport goods?
The superspeed maglev system is suited to transport valuable express goods that can be packed into containers. Special vehicles are available for freight traffic. The freight sections can be combined to form goods-only trains and mixed trains carrying both passengers and freight. Each freight section has a capacity of 17 t. The operating speeds of freight vehicles and passenger vehicles are the same. The maglev system is not designed to transport heavy and bulk goods because it isn't reasonable to transport coal, ore, steel or oil at 500 km/h.

 

2-4) Do you have to wear a seat belt or support yourself during starting, braking or driving?
For reasons of comfort the acceleration and deceleration of the superspeed maglev system (< 1.0 m/s²) corresponds to that of short-distance transport services (up to 1.3 m/s²). However, comfort is mostly affected by jerks (meaning sudden changes in acceleration) as experienced in trains, for example when switches are passed over. There are practically no such jerks in the Transrapid, so you can enjoy your ride and move freely around the vehicle at any time.
 

2-5) Does the superspeed maglev system require additional traffic routes?
In order to cope with growing traffic volumes and in particular relocate a substantial part of the traffic from roads (passengers and goods) and air to railborne transport, the attractiveness of railroad systems needs to be enhanced by means of higher speed and, consequently, shorter journey times. This requires new tracks both for the ICE and for superspeed maglev systems, because the ICE cannot reach its speed (250 km/h) on existing railroad tracks. Rather, the ICE is a "normal train" and not a high-speed system where it uses existing tracks. However, thanks to its favorable route alignment parameters, the Transrapid guideway can be bundled with existing traffic routes in most cases.
 

2-6) How is the guideway kept clean?
Neither rain nor snow or hail lead to any restrictions in the operation of the Transrapid system. The upper side of the Transrapid's guideway is designed in such a way that it is a plane surface, so that drainage is guaranteed for any type of route alignment. For a straight this means that the guideway is designed with a 2 %, so that drainage of the smooth and plane surface is via the sides.
 

2-7) How is the superspeed maglev system tested in practice?
The superspeed maglev system is being tested in long-term operation under realistic conditions on the Transrapid Versuchsanlage Emsland (TVE, Transrapid Test Facility Emsland) since 1984. This unique facility provides a closed course with two loops and a total length of 31.5 km, a test center and test vehicles. Until today the TR06, TR07 and TR08 pilot vehicles have covered more than 725,000 km on the single-track TVE. As most wearing mechanical components have been replaced by electromechanical and electronic components, they can be tested in parallel with the operation on the test facility on special test stands with realistic simulation of the stresses. These tests with several thousands of operating hours mean a total "running performance" of more than 600,000 km.
 

2-8) How many passengers can a Transrapid vehicle seat?
The vehicles comprise a minimum of two sections. Each section seats around 90 passengers. Therefore, a vehicle consisting of two sections offers up to 180 seats at a length of 51 m. However, an upper limit is defined by the length of the station platforms, so a vehicle will not be longer than ten sections. This means about 900 seats without affecting the operating speed.
 

2-9) Is the superspeed maglev system ready for application?
Following comprehensive testing and evaluations, a team of experts from Deutsche Bundesbahn and leading university institutes under the management of the German Federal Railway Authority in Munich has in a final expert opinion in December 1991 declared the superspeed maglev system ready for technical application without any restrictions. Thus the Transrapid is the world's first superspeed maglev system ready for operation. The expert opinion certifying "readiness for technical application" applies to the vehicle, the levitation and guidance system, the propulsion system, the power supply, the operation control system, the communication system, the guideway and the switches, and the system technology (safety, sound emission, aerodynamics). All sub-systems and components have been tested and evaluated with regard to operatability, reliability, availability, safety, operation control, flexibility, failure tolerance, maintainability, environmental compatibility, system compatibility and comfort requirements. The Transrapid is the first railroad system ever that has been analyzed, tested and evaluated in such a comprehensive way by independent experts.
 

2-10) Is the Transrapid favorable only at very high speeds?
Of course, the Transrapid can also be applied at much lower speeds. At lower speeds still considerably higher than the maximum speeds of modern wheel-on-rail systems, the other system advantages such as lower energy consumption, lower wear and substantially less sound emission are particularly beneficial. Adding to this is that the Transrapid can accelerate much faster than wheel-on-rail systems without restrictions of comfort and therefore reaches its speed after a very short distance.
 

2-11) May transrapid vehicles collide?
The guideway of the superspeed maglev system has no crossings. Other traffic routes usually pass under the Transrapid guideway, therefore the train cannot collide with other vehicles. The principle of the long-stator motor also prevents collision of Transrapid vehicles traveling at different speeds (running into a slower vehicle) and frontal collision, because the vehicle and the motor's traveling field always move synchronous, i.e. at the same speed and in the same direction. Moreover, only the guideway motor section on which the vehicle is moving is in operation.
 

2-12) To what degree (angle) can a Transrapid train climb?
As the propulsion system is installed in the guideway, the motor power for peak requirements can be sized to fit the local topography. In this way its possible to climb steep grades of up to 10 %.
 

2-13) What distances between the stations are required for the superspeed maglev system to make full use of its high speed?
As a rule, superspeed maglev stations can be provided at shorter intervals than in the case of railroad at the same design speeds without affecting journey times, because short acceleration and braking distances are possible without any restrictions of comfort. For example, the superspeed maglev system requires just 5 km to accelerate to a speed of 300 km/h from a standing start. A modern wheel-on-rail system such as the ICE requires about 30 km to reach the same speed from a standing start.
 

2-14) What does "readiness for technical application" mean?
This means that the superspeed maglev system holds no system risks and safety risks as a whole and with regard to its sub-systems, that the necessary investments can be calculated with sufficient accuracy and that the planning and approval procedures required can commence. With the certification of readiness for application, one of the most important prerequisites for the inclusion of application routes into the new German Federal Master Plan is met. The results of a comparative study by the Federal Ministries of Transport and of Research and Technology, Deutsche Bundesbahn, Deutsche Lufthansa, Deutsche Eisenbahn Consulting GmbH, Dornier GmbH and Versuchs- und Planungsgesellschaft für Magnetbahnsysteme mbH (MVP) on the basis of model routes show that the new railroad system is economically viable. Additionally, it has been found that the superspeed maglev system is quieter than other railroad systems at the same speed, consumes specifically less energy and requires comparably less space for its guideway.
 

2-15) What happens when a switch is not completely set?
Switches are set taking account of safety aspects, as in the case of conventional railroad. A switch can only be set after the train has passed and the set of switches has been subsequently blocked. Only after the switch is correctly set in the new position and locked, and after this has been verified by signals, can the set of switches be released for the next train. If this condition is not met, the train is automatically stopped at the calculated stopping distance, so it comes to a halt before the faulty switch.
 

2-16) What happens when the vehicle breaks down?
The Transrapid vehicles are designed in such a way that they will head for the next station in an emergency. This concept is based on the idea that, for example in the case of a fire or similar event, the stopping areas will provide the best means of help. Newly constructed railroad tracks are also designed in such a way that the train cannot stop at any section of the route because not all places are suitable to rescue passengers (e.g. tunnels). When the propulsion system fails (due to land-line network breakdown) it is not necessary to leave the vehicle.
 

2-17) What is "broken traffic"?
When different transport systems are connected, changing is unavoidable. This applies even today when the most appropriate and fastest means of transport is used (e.g. car/short-distance service -> railroad and vice versa or car/short-distance service/railroad -> airplane). Even within a single transport system passengers often have to change, e.g. from one train to another, to reach their final destination. An average of 50% of train passengers have to change at least once. In many European cities such as Paris passengers additionally have to change stations frequently and the Japanese Shinkansen high-speed trains even consists of several separate systems.
 

2-18) What is the minimum interval at which maglev trains can operate?
At the moment we are reckoning on a minimum interval between trains of 5 minutes. This interval length is mainly defined by safety requirements and regulations. Limitations exist with regard to the clearing and formation times of the individual guideway segments due to the operation control system and switch setting times. The frequency also depends on the operating concept and the desired speed.
 

2-19) What is the Transrapid's curve radius?
The curve radii of modern high-speed systems result in dependence on the speed and the maximum possible superelevation of the guideway to compensate for the centrifugal forces occurring. The Transrapid's guideway can have a maximum superelevation of 12 degree (up to 16 degree in special cases) which allows smaller radii at higher speeds than in the case of conventional wheel-on-rail systems.
- Minimal radius: 350 m
- 200 km/h: 705 m
- 400 km/h: 2,825 m
- 500 km/h: 4,415 m

2-20) What is the width of the guideway pitch between two rails?
The distance between two rails depend on the speed of the trains. The guideway pitch (distance between the centrelines of two maglev guideways) is:
- up to 300 km/h (186 mph): 4.4 m
- up to 400 km/h (248 mph): 4.8 m
- up to 500 km/h (310 mph): 5.1 m
 

2-21) What is the width of the track gauge?
The track gauge is 2.8 m.
 

2-22) What limits the Transrapid's maximum speed?
There are hardly any technical limits with regard to the maximum speed. In general, limiting factors are economical because the expenditure required to reach higher speeds is not in proportion with the benefits to be gained. Possible maximum speed is generally limited by aerodynamics. In particular in oncoming traffic, the air pressure generated at speeds far higher than 500 km/h is similar to that occurring when the sound barrier is broken. This could be handled by providing appropriate distances between the guideways, by single-track construction or, similar to the Swiss project, by installing the system in pipes which are free from air which eliminates all aerodynamic effects. Another precondition for higher speeds is more exact construction to equalize the forces interacting between the vehicle and the guideway. For example, the beam per-curvature would have to be reduced and the general route alignment parameters such as curve radii and gradients would have to be altered to minimize possible transverse and vertical acceleration forces. Provided that the guideway is appropriately constructed, gap regulation of the magnets does not restrict the maximum speed.
 

2-23) When is the superspeed maglev system ready to go into production?
The development of the new railroad system has been completed and the system has been ready for production since 1995, so construction of the first German superspeed maglev route could start from a technical point of view.
 

2-24) Who is inspecting the Transrapid and gives official approval for operation?
As in the case of conventional railroad the Eisenbahnbundesamt (EBA, Federal Railway Authority) near Bonn is the competent sovereign and independent authority for the Transrapid. The EBA uses approved experts such as universities, engineering firms and Technical Inspection Associations. Approval is given on the basis of the Magnetbahn Betriebs- und Zulassungsordnung (MbBO, Maglev Construction and Operation Ordinance).
 

2-25) Why operating speeds up to 500 km/h?
The planning and development works for the Transrapid system have been based on the design speed of 400 km/h, because this allows day trips on nearly all connections in the Federal Republic of Germany with journey times of less than three hours and a minimum stay of six hours at the destination. Where this is possible without considerable extra cost, increasing the speed to 500 km/h results in even better use of the traffic potential by relocating traffic from private cars to the superspeed maglev system. Increases beyond this speed would bring no additional benefits and are therefore not reasonable although this is technically possible.
 

2-26) Will passengers profit from the Transrapid even if their place of departure or destination is not near a Transrapid station?
Considerable reductions in journey times can be enjoyed not only by passengers on direct Transrapid connections but by all train passengers due the inclusion of Transrapid routes on the existing high-speed railroad network.

 

3) Application:

 

3-1) Does the superspeed maglev system compete with Deutsche Bahn?
The superspeed maglev system is not competing with Deutsche Bahn (DB). On the contrary: the superspeed maglev system provides DB with an additional modern product to crucially enhance and improve the attractiveness of its services while at the same time allowing it to reduce its operating costs. Additionally, the superspeed maglev system improves DB's competitive position with regard to freight traffic. On the one hand, because the Transrapid itself can transport express goods and, on the other, because tracks are relieved from part of the passenger traffic. This deallocates capacity which is urgently needed to cope with the still growing demand for freight traffic and to relocate more goods from the road to the rail.
 

3-2) What is the difference between the Japanese and the German superspeed maglev system?
Superspeed maglev systems consist of different possible combinations of a magnetic levitation system and a non-contact propulsion system. In Germany, almost all possible combinations have been developed and tested until 1977 before the decision was made in favor of the current system. In contrast to the German Transrapid that encompasses its guideway and is pulled towards the guideway table from below by its electromagnetic levitation system, the Japanese Chuo Shinkansen runs in a U-shaped guideway and is held in its track from the sides by an electrodynamic levitation system (repulsive principle). Superconductive coils in the vehicle cooled with liquid helium generate very strong magnetic fields which induce an inverse magnetic field in the passive reaction coils in the guideway. Beyond a speed of about 100 km/h these fields are sufficiently strong to suspend the vehicle. Up to that speed the Chuo Shinkansen moves on wheels. The Transrapid's gap width is 8 to 10 mm, that of the Chuo Shinkansen 10 cm. Both trains are propelled by means of a long-stator motor in the guideway. Disadvantages of the Japanese technology are the high costs, the high technological expenditure for the high-temperature superconductors and the extreme magnetic fields inside the vehicles. Additionally, the unregulated levitation system of the Chuo Shinkansen means much less comfort. An advantage is that is earthquakeproof. The combination also tested in Germany until 1977 of an electromagnetic levitation system and a short-stator motor in the vehicle has been further developed in Japan as HSST (High Speed Surface Transport). However, this system is not suited for high speeds and therefore only considered as a short-distance means of transport.

 

 

4) Environment:

 

4-1) Can the guideway run at grade?
The elevated guideway is not required by the system but it is reasonable for ecological and topographical reasons. However, where this is necessary for reasons of noise protection or acceptance, the guideway is built at grade. The at-grade guideway also consumes less soil than a railroad track and small animals can pass under the guideway plate as there needs to be a clearance for constructional reasons.
 

4-2) Can the noise produced by the superspeed maglev system be further reduced?
The potential for a further reduction of the sound emission by optimizing the vehicle's aerodynamic properties is considerable. For example, the sound levels of the Transrapid 07 where between 4 and 5 dB below those generated by the Transrapid 06 test vehicle. Additionally, the accelerating power of the superspeed maglev system offers the possibility to flexibly adjust its speed to the requirements without increasing the journey time. The Transrapid can hover into city centers through residential areas at a speed of 200 km/h and is then quieter than sub-urban trains.
 

4-3) Can the superspeed maglev system relieve air traffic and thus contribute to reducing the environmental damage done by air traffic?
The superspeed maglev system is in particular attractive for air passengers. Effective journey times are roughly the same and safety, comfort and accessibility of its terminals in connection with other transport systems additionally speak in favor of the Transrapid. Due to this attractiveness, a considerable part of the domestic air traffic can be relocated to the superspeed maglev system. Relocation of the air traffic to the environmentally friendlier and energy-saving combination of wheel-on-rail and superspeed maglev system results in a corresponding relieve of the environment and a reduction in energy consumption. This effect cannot be achieved by the railroad alone.
 

4-4) Can the Transrapid guideway be bundled with existing traffic routes?
Traffic routes can become a burden on the environment. Therefore, route alignments for superspeed maglev systems are planned to run along existing traffic routes (freeways, railroad tracks) wherever possible. Bundling of the superspeed maglev system's guideway with existing traffic routes is made possible in particular by the flexibility of the route alignment parameters (high gradients and narrow curve radii possible).
 

4-5) Can wild and other animal's unrestrictedly cross the superspeed maglev guideway?
In contrast to roads and rails, the (elevated) guideway of the superspeed maglev system doesn't prevent game, amphibians and small animals from crossing. Collision with these animals is therefore ruled out. The at-grade guideway, too, provides a clearance under the guideway plate because of construction requirements where small animals and amphibians can pass. Due to the height of the guideway table, collision with game is not possible. Experience gathered during the operation of the Transrapid Versuchsanlage Emsland (TVE, Transrapid Test Facility Emsland) which mainly runs through agricultural land shows that cows and other animals quickly get used to the traffic and show no reaction such as flight etc.
 

4-6) Do the foundations of the guideway columns affect the water resources or ground water?
It is one of the essential advantages of the superspeed maglev guideway (at-grade and elevated) that it doesn't affect the water resources. The intervention in the ground required for the column foundations are minimal compared to conventional construction. Usually, surface foundations are installed which are not even as deep as a normal cellar. Pile foundation is necessary in some exceptional cases only. As the regular guideway in contrast to roads and railroad tracks doesn't make it necessary to change the topography of the terrain, no drainage ditches like those for other traffic routes are required.
 

4-7) How "loud" is the superspeed maglev system?
In contrast to all other ground transport systems, the Transrapid doesn't make any rolling or propulsion noises thanks to its non-contact technology. Only when its speed reaches 250 to 300 km/h aerodynamic noise (wind) will become perceivable. At a usual distance of 100 m to buildings the peak sound level at 250 km/h is just 71 dB(A) and thus almost entirely vanishes in the ambient noise, compared to around 80 dB(A) of inner-city road traffic. Levels are even some dB lower in the case of at-grade guideways. Increases in the sound levels result from the wear of wheels and rails in the case of conventional railroad which according to DB are restricted to a maximum of 6 dB by regular grinding of the rails where newly constructed tracks run near residential buildings. Thanks to its non-contact technology, the Transrapid rails are not subject to wear and therefore its sound levels do not increase.
 

4-8) How is noise measured and what does dB(A) mean?
Whether or not a noise is felt as being pleasant or annoying depends on a persons individual valuation. Such subjective sensations cannot be measured objectively. What can be measured, though, are noise levels, i.e. pressure variations in air generated by a source of sound. Sound pressure levels are measured in dB(A). This uniform international unit of measurement models the sensitivity of our hearing. The scale reaches from 0 dB(A) (threshold of audibility) to 130 dB(A) (threshold of pain). The decibel scale is logarithmic, i.e. an increase of 10 dB(A) is felt as a doubling of the loudness level. Sound levels of common noises:
- 0 to 20 dB(A): practically only audible under laboratory conditions
- 20 to 30 dB(A): ambient noise far from towns and roads with no strong wind blowing
- 40 to 60 dB(A): conversation at normal volume
- 60 to 65 dB(A): radio/TV at moderate volume
- 70 to 90 dB(A): city traffic
- 100 dB(A) and more: disco/pneumatic hammer
- up to 130 dB(A): jet engine at a distance of 100

 

4-9) How much energy does the superspeed maglev system consume?
At comparable speeds, the Transrapid consumes around 30% less energy than the high-speed ICE. In other words, with the same amount of energy the superspeed maglev system provides a third more performance. Road traffic consumes 3.5 times and short-distance air traffic 4 times more energy than the superspeed maglev system (at 400 km/h) referred to the same transportation volume.
 

4-10) Is it necessary to have a service road running alongside the guideway?
A service road is only required during construction but not after completion of the guideway. Parts of the service road along the Transrapid Versuchsanlage Emsland (TVE, Transrapid Test Facility Emsland) have been pulled down. Where they have been kept, this was not for system-related reasons as a service road is required neither for safety nor guideway maintenance (maintenance is from the guideway).
 

4-11) What are the advantages of the elevated guideway?
No grass grows where concrete tracks or beds of broken stone are built. And even though the eye has long accustomed to the sight, embankments, walls, roads and rails cut through the landscape and affect water resources, mesoclimate, fauna and flora. Therefore, every new kilometer of traffic routes means a burden on the environment. The Transrapid's guideway built on slender columns consumes less space and neither cuts through the landscape nor through grown structures. The surface under the guideway can still be used, e.g. for agriculture or other traffic. There are no "dead surfaces" as in the case of bridges and embankments. Small game and amphibians can pass under the guideway and biological life dependencies are not cut up. In contrast to embankments and walls, the Transrapid's guideway doesn't affect the mesoclimate. An service road running alongside the route is not required.

 

 

5) Economic Efficiency:

 

5-1) What does it cost to built the Transrapid?
The investment required for a superspeed maglev system is comparable to the investment for the guideway of high-speed wheel-on-rail systems. The comparison of route investment costs is the more in favor of the superspeed maglev the more difficult the terrain is, because the favorable route alignment parameters allow flexible adaptation of the guideway to topographic conditions, so that in contrast to railroad expensive special civil structures such as tunnels and embankments and cuts are rarely needed.

5-2) What does it cost to operate the Transrapid?
The Transrapid can be operated at considerably lower costs than other comparable traffic systems where the cost of personnel, maintenance, repair and energy are the main factors. All in all, the specific costs of operating the superspeed maglev system are just about half of what operation of conventional railroad long-distance traffic costs. For example, the non-contact technology is almost non-wearing (the main cause of mechanical wear is friction to which the superspeed maglev system is not subjected). Wearing mechanical components are to a large extent replaced by non-wearing electronic and electromagnetic components, the vehicle's load doesn't act on points (as in the case of axle loads of trains) but on the guideway as line load distributed over the entire length of the vehicle. Additionally, the specific energy consumption (per seat) is lower than that of any other comparable traffic system.



[Source: ThyssenKrupp Transrapid GmbH] 

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