Editing Transrapid (section)

==Technology==
{{see also|Maglev#Technology}}
{{More citations needed section|date=April 2022}}

===Levitation===
The super-speed Transrapid maglev system has no wheels, no axles, no gear transmissions, no steel rails, and no overhead electrical [[Pantograph (transport)|pantographs]]. The maglev vehicles do not roll on wheels; rather, they hover above the track guideway, using the [[Electromagnetic suspension|attractive magnetic force between two linear arrays of electromagnetic coils]]—one side of the coil on the vehicle, the other side in the track guideway, which function together as a magnetic dipole. During levitation and travelling operation, the Transrapid maglev vehicle floats on a frictionless magnetic cushion with no mechanical contact whatsoever with the track guideway. On-board vehicle electronic systems measure the dipole gap distance 100,000 times per second to guarantee the clearance between the coils attached to the underside of the guideway and the magnetic portion of the vehicle wrapped around the guideway edges. With this precise, constantly updated electronic control, the dipole gap remains nominally constant at {{convert|10|mm}}. When levitated, the maglev vehicle has about {{convert|15|cm}} of clearance above the guideway surface.

The Transrapid maglev vehicle requires less power to hover than it needs to run its on-board air conditioning equipment.

In Transrapid vehicle versions TR08 and earlier, when travelling at speeds below {{Convert|80|km/h}}, the vehicle levitation system and all on-board vehicle electronics were supplied with power through physical connections to the track guideway. At vehicle speeds above {{Convert|80|km/h}}, all on-board power was supplied by recovered [[Harmonic oscillator|harmonic oscillation]] of the [[magnetic field]]s created from the track's linear stator. (Since these oscillations are parasitic, they cannot be used for vehicle propulsion). A new energy transmission system, version TR09, has since been developed for Transrapid, in which maglev vehicles now require no physical contact with the track guideway for their on-board power needs, regardless of the maglev vehicle speed. This feature helps to reduce on-going maintenance and operational costs.

In case of power failure of the track's propulsion system, the maglev vehicle can use on-board backup batteries to temporarily power the vehicle's levitation system.

===Propulsion===
The Transrapid maglev system uses a synchronous ''longstator'' [[linear motor]] for both propulsion and braking. It works like a rotating [[electric motor]] whose [[stator]] is "unrolled" along the underside of the guideway; instead of producing [[torque]] (rotation) it produces a linear force along its length. The electromagnets in the maglev vehicle which lift it also work as the equivalent of the excitation portion ([[Rotor (electric)|rotor]]) of this linear electric motor. Since the magnetic travelling field works in only one direction, if there were to be several maglev trains on a given track section, they would all travel in the same direction thereby reducing the possibility of collision between moving trains.

===Energy requirements===
The normal energy consumption of the Transrapid is approximately {{convert|50|to|100|kW}} per section for levitation and travel, and vehicle control. The [[drag coefficient]] of the Transrapid is about 0.26. The [[aerodynamic drag]] of the vehicle, which has a frontal cross section of {{Convert|16|m2|0|abbr=on}},{{Citation needed|date=May 2014}} requires a power consumption, at {{Convert|400|km/h|0|abbr=on}} or {{Convert|111|m/s|0|abbr=on}} cruising speed, given by the following formula:

<math>
P = c_w \cdot A_{\rm Front} \cdot v^3 \cdot (\mbox{density of surrounding air})/2
</math>

<math>
\begin{matrix}
P &=& 0{.}26 \cdot 16\,\mathrm{m}^2 \cdot (111\,\mathrm{m}/\mathrm{s})^3 \cdot 1{.}24\,\mathrm{kg}/\mathrm{m}^3 /2 \\
P &=& 3{.}53\cdot10^6\,\mathrm{kg}\cdot\mathrm{m}^2/\mathrm{s}^3 = 3{.}53\cdot10^6\,\mathrm{N}\cdot\mathrm{m}/\mathrm{s} = 3{.}53\,\mathrm{MW}
\end{matrix}
</math>

Power consumption compares favourably with other high-speed rail systems. With an efficiency of 0.85, the power required is about 4.2&nbsp;MW. Energy consumption for levitation and guidance purposes equates to approximately 1.7&nbsp;kW/t. As the propulsion system is also capable of functioning in reverse, energy is transferred back into the [[electrical grid]] during braking. An exception to this is when an emergency stop is performed using the emergency landing skids beneath the vehicle, although this method of bringing the vehicle to a stop is intended only as a last resort should it be impossible or undesirable to keep the vehicle levitating on back-up power to a natural halt.

===Market segment and historical parallels===
Compared to classical railway lines, Transrapid allows higher speeds and gradients with less weathering and lower energy consumption and maintenance needs. The Transrapid track is more flexible, and more easily adapted to specific geographical circumstances than a classical train system. Cargo is restricted to a maximum payload of {{Convert|15|t|1|lk=on|abbr=off}} per car. Transrapid allows maximum speeds of {{Convert|550|km/h|0|abbr=on}}, placing it between conventional high speed trains ({{Convert|200|–|320|km/h|0|disp=or|abbr=on}}) and air traffic ({{Convert|720|–|990|km/h|0|disp=or|abbr=on}}). The magnetic field generator, an important part of the engine being a part of the track, limits the system capacity.

From a competition standpoint, the Transrapid is a proprietary solution. The track being a part of the engine, only the single-source Transrapid vehicles and infrastructure can be operated. There is no multisourcing foreseen concerning vehicles or the highly complicated crossings and switches. Unlike classical railways or other infrastructure networks, as jointly administrated by the [[Federal Network Agency]] (Bundesnetzagentur) in Germany, a Transrapid system does not allow any direct competition.

===Ecological impact===
The Transrapid is an electrically driven, clean, high-speed, high-capacity{{Citation needed|date=January 2011}} means of transport able to build up point-to-point passenger connections in geographically challenged surroundings. This has to be set in comparison with the impact on heritage and or landscape protection areas (compare [[Waldschlösschen Bridge]]). Any impact of emissions has to take into account the source of electrical energy. The reduced expense, noise and vibration of a people-only Transrapid system versus a cargo train track is not directly comparable. The reuse of existing tracks and the interfacing with existing networks is limited. The Transrapid indirectly competes for resources, space and tracks in urban and city surroundings with classical urban transport systems and high speed trains.

===Comparative costs===
====Track construction cost====
The fully elevated [[Shanghai Maglev]] was built at a cost 
of US$1.33&nbsp;billion over a length of {{convert|30.5|km}} including trains and stations. Thus the cost per km for dual track was US$43.6&nbsp;million, including trains and stations. This was the first commercial use of the technology. Since then conventional fast rail track has been mass-produced in China for between US$4.6 and US$30.8&nbsp;million per kilometer, mostly in rural areas. (See [[High-speed rail in China]]).

In 2008 Transrapid Australia quoted the [[Victoria (Australia)|Victoria]] State Government [[Australian dollar|A$]]34 million per kilometer for dual track.<ref Name="Transrapid quote to Victorian Government">[http://210.15.220.118/ewlna_submissions/EastWestResponse_100708_ThyssenKruppTransrapidAustralia.pdf Transrapid quote to Victorian Government]{{dead link|date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> This assumed 50% of the track was at grade and 50% was elevated. In comparison, the {{convert|47|km}} [[Regional Rail Link]] built in Victoria cost around A$5 billion, or A$105 million per kilometer, including two stations.

From the above it is not possible to say whether Transrapid or conventional fast rail track would be cheaper for a particular application.

The higher operating speed of the maglev system will result in more passengers being delivered over the same distance in a set time. The ability of the Transrapid system to handle tighter turns and steeper gradients could heavily influence a cost comparison for a particular project.

====Train purchase cost====
In 2008, Transrapid Australia quoted the [[Victoria (Australia)|Victorian]] State Government between A$16.5 million (commuter) and A$20 million (luxury) per trains section or carriage.<ref name="Transrapid quote to Victorian Government"/> Due to the {{convert|3.7|m|ftin|abbr=on}} width of the Transrapid carriages they have a floor area of about {{Convert|92|m2|0|abbr=off|sp=us}}. This works out at between A$179,000 and A$217,000 per square meter.

In comparison, [[InterCityExpress]] which are also built by [[Siemens]] cost about A$6 million per carriage. Due to the {{Convert|2.9|m|ftin|abbr=on}} width of the ICE carriages they have a floor area of about {{Convert|72|m2|0|abbr=off|sp=us}}. This works out at about A$83,000 per square meter.

This shows Transrapid train sets are likely to cost over twice as much as ICE 3 conventional fast rail train sets at this time. However, each Transrapid train set is more than twice as efficient due to their faster operating speed and acceleration according to [[UK Ultraspeed]]. In their case study only 44% as many Transrapid train sets are needed to deliver the same number of passengers as conventional high-speed trains.

====Operational cost====
Transrapid claims their system has very low maintenance costs compared to conventional high speed rail systems due to the non-contact nature of their system.<ref Name="Transrapid International">[http://www.transrapid.de/cgi/en/basics.prg?session=76d1f56f4da67ae8_285873&a_no=35 Transrapid Website - Economic Efficiency] {{webarchive|url=https://web.archive.org/web/20110719234220/http://www.transrapid.de/cgi/en/basics.prg?session=76d1f56f4da67ae8_285873&a_no=35 |date=2011-07-19 }}</ref>