Neither Inductrack nor the Superconducting EDS are able to levitate vehicles at a standstill, although Inductrack provides levitation down to a much lower speed. Wheels are required for both systems. EMS systems are wheel-less.
The German Transrapid, Japanese HSST (Linimo), and Korean Rotem EMS maglevs levitate at a standstill, with electricity extracted from guideway using power rails for the latter two, and wirelessly for Transrapid. If guideway power is lost on the move, the Transrapid is still able to generate levitation down to 10 km/h speed, using the power from onboard batteries. This is not the case with the HSST and Rotem systems.
[edit] Propulsion
An EMS system can provide both levitation and propulsion using an onboard linear motor. EDS systems can only levitate the train using the magnets onboard, not propel it forward. As such, vehicles need some other technology for propulsion. A linear motor (propulsion coils) mounted in the track is one solution. Over long distances where the cost of propulsion coils could be prohibitive, a propeller or jet engine could be used.
[edit] Stability
Static magnetic bearings using only electromagnets and permagnets are unstable, as explained by Earnshaw's theorem. EMS systems rely on active electronic stabilization. Such systems constantly measure the bearing distance and adjust the electromagnet current accordingly. As all EDS systems are moving systems (i.e. no EDS system can levitate the train unless it is in motion), Earnshaw's theorem does not apply to them.
[edit] Pros and cons of maglev vs. conventional trains
Due to the lack of physical contact between the track and the vehicle, there is no rolling friction, leaving only air resistance (although maglev trains also experience electromagnetic drag, this is relatively small at high speeds). [1]
Maglevs can handle high volumes of passengers per hour (comparable to airports or eight-lane highways) and do it without introducing air pollution along the right of way. Of course, the electricity has to be generated somewhere, so the overall environmental impact of a maglev system is dependent on the nature of the grid power source.
The weight of the large electromagnets in EMS and EDS designs is a major design issue. A very strong magnetic field is required to levitate a massive train. For this reason one research path is using superconductors to improve the efficiency of the electromagnets.
Due to its high speed and shape, the noise generated by a maglev train is similar to a jet aircraft, and is considerably more disturbing than standard steel on steel intercity train noise. A study found the difference between disturbance levels of maglev and traditional trains to be 5dB (about 78% noisier).[2]
[edit] Economics
The Shanghai maglev cost 9.93 billion yuan (US$1.2 billion) to build.[3] This total includes infrastructure capital costs such as manufacturing and construction facilities, and operational training. At 50 yuan per passenger[4] and the current 7,000 passengers per day, income from the system is incapable of recouping the capital costs (including interest on financing) over the expected lifetime of the system, even ignoring operating costs.
China aims to limit the cost of future construction extending the maglev line to approximately 200 million yuan (US$24.6 million) per kilometer.[3] These costs compare competitively with airport construction (e.g., Hong Kong Airport cost US$20 billion to build in 1998) and eight-lane Interstate highway systems that cost around US$50 million per mile in the US.
While high-speed maglevs are expensive to build, they are less expensive to operate and maintain than traditional high-speed trains, planes or intercity buses. Data from the Shanghai maglev project indicates that operation and maintenance costs are covered by the current relatively low volume of 7,000 passengers per day. Passenger volumes on the Pudong International Airport line are expected to rise dramatically once the line is extended from Longyang Road metro station all the way to Shanghai's downtown train depot.
The proposed Chūō Shinkansen maglev in Japan is estimated to cost approximately US$82 billion to build.
The only low-speed maglev (100 km/h) currently operational, the Japanese Linimo HSST, cost approximately US$100 million/km to build[5]. Besides offering improved O&M costs over other transit systems, these low-speed maglevs provide ultra-high levels of operational reliability and introduce little noise and zero air pollution into dense urban settings.
As maglev systems are deployed around the world, experts expect construction costs to drop as new construction methods are perfected.[citation needed]
[edit] Historical maglev systems
[edit] First patents
High speed transportation patents would be granted to various inventors throughout the world.[6] Early United States patents for a linear motor propelled train were awarded to the inventor, Alfred Zehden (German). The inventor would gain U.S. Patent 782,312 (Jun 21, 1902) and U.S. Patent RE12,700 (Aug 21, 1907).[7] In 1907, another early electromagnetic transportation system was developed by F. S. Smith[8]. A series of German patents for magnetic levitation trains propelled by linear motors were awarded to Hermann Kemper between 1937 and 1941[9]. An early modern type of maglev train was described in U.S. Patent 3,158,765 , Magnetic system of transportation, by G. R. Polgreen (Aug 25, 1959). The first use of "maglev" in a United States patent was in "Magnetic levitation guidance"[10] by Canadian Patents and Development Limited.
[edit] Hamburg, Germany 1979
Transrapid 05 was the first maglev train with longstator propulsion licensed for passenger transportation. In 1979 a 908 m track was open in Hamburg for the first International Transportation Exhibition (IVA 79). There was so much interest that operation had to be extended three months after exhibition finished, after carrying more than 50,000 passengers. It was reassembled in Kassel in 1980.
[edit] Birmingham, England 1984–1995
The world's first commercial automated system was a low-speed maglev shuttle that ran from the airport terminal of Birmingham International Airport (UK) to the nearby Birmingham International railway station from 1984 to 1995. Based on experimental work commissioned by the British government at the British Rail Research Division laboratory at Derby, the length of the track was 600 m, and trains "flew" at an altitude of 15 mm. It was in operation for nearly eleven years, but obsolescence problems with the electronic systems made it unreliable in its later years and it has now been replaced with a cable-drawn system.
Several favourable conditions existed when the link was built.
- The BR Research vehicle was 3 tons and extension to the 8 ton vehicle was easy.
- Electrical power was easily available.
- Airport and rail buildings were suitable for terminal platforms.
- Only one crossing over a public road was required and no steep gradients were involved
- Land was owned by Railway or Airport
- Local industries and councils were supportive
- Some Government finance was provided and because of sharing work, the cost per organisation was not high.
[edit] Mid to late 1980s
In Tsukuba, Japan (1985), the HSST-03 wins popularity in spite of being 30 km/h and a run of low speed in Tsukuba World Exposition. In Vancouver, Canada (1986), the JR-Maglev took a test ride at holding Vancouver traffic exhibition and runs. In Okazaki, Japan (1987), the JR-Maglev took a test ride at holding Okazaki exhibition and runs. In Saitama, Japan (1988), the HSST-04-1 exhibited it at Saitama exhibition performed in Kumagaya, and runs. Best speed per hour 30 km/h. In Hamburg, Germany (1988), the TR-07 in international traffic exhibition (IVA88) performed Hamburg. in Yokohama, Japan (1989), the HSST-05 acquires a business driver's license at Yokohama exhibition and carries out general test ride driving. Maximum speed 42 km/h.
[edit] Berlin, Germany 1989–1991
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In West Berlin, the M-Bahn was built in the late 1980s. It was a driverless maglev system with a 1.6 km track connecting three stations. Testing in passenger traffic started in August 1989, and regular operation started in July 1991. Although the line largely followed a new elevated alignment, it terminated at the U-Bahn station Gleisdreieck, where it took over a platform that was then no longer in use; it was from a line that formerly ran to East Berlin. After the fall of the Berlin Wall, plans were set in motion to reconnect this line (today's U2). Deconstruction of the M-Bahn line began only two months after regular service began and was completed in February 1992.
[edit] The history of maximum speed record by a trial run
- 1971 - West Germany - Prinzipfahrzeug - 90 km/h
- 1971 - West Germany - TR-02 - 164 km/h
- 1972 Japan - ML100 - 60 km/h - (manned)
- 1973.end - West Germany - TR04 - 250(manned)
- 1974 - West Germany - EET-01 - 230 km/h(Unmanned)
- 1975 - West Germany - Komet - 401.3 km/h (by steam rocket propulsion).(Unmanned)
- 1978 - Japan - HSST01 - 307.8 km/h(by Supporting Rockets propulsion, made in Nissan).(Unmanned)
- 1978 - Japan - HSST02 - 110 km/h (manned)
- 1979 - Japan - ML500 - 517 km/h (unmanned)
- 1987 - West Germany - TR06 - 406 km/h(manned)
- 1987 - Japan - MLU001 - 400.8 km/h(manned)
- 1988 - West Germany - TR-06 - 412.6 km/h (manned)
- 1989 - West Germany - TR-07 - 436 km/h (manned)
- 1993 - Germany - TR-07 - 450 km/h(manned)
- 1994 - Japan - MLU002N-431 km/h(unmanned)
- 1997 - Japan - MLX01 - 531 km/h (manned)
- 1997 - Japan - MLX01 - 550 km/h (unmanned)
- 1999 - Japan - MLX01 - 548 km/h (unmanned)
- 1999 - Japan - MLX01 - 552 km/h (manned/Five formation). Guinness authorization.
- 2003 - Germany - TR-08 - 501 km/h (manned)
- 2003 - Japan - MLX01 - 581 km/h (manned/Three formation). Guinness authorization.
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