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High speed ground transportation
TtdmoiogyIn Society, Vol. 6,pp. 141-149(1984) Printed in the USA. All rights rcsetved.
0160-791X/84$3.00
+
.OO
Copyright o 1984 Petgamon Press Ltd
High Speed Ground Transportation Some Current and Future Alternatives Terz+!oModa
ABSTRACT. High-speed transportation, the value of time, and the socia/ and technological’considerations of inter-city transportation wi’l be discussedin this article. A particularly promising mode of high-speedground transportation (MAGLEI/;) wi’l be discussed in some detail’. An average speedfor HSGTservice, 400 Rilbmetersper hour, seems to be attainabLe for reasons that wi’l be set forth. In conclusion, the proposal for a “hypersonic” subway wil’l be anaLyzea’.
When there are several modes of transport between a place of origin and a destination, it is not necessary for all travelers to choose the fastest one. But, throughout history- whether a person has been traveling by land, sea or air-speed has always been at a premium, and has been a major influence in the choice of means of transportation. Slower modes of transport have been eliminated, and faster ones introduced; thus the average speed of all methods has been increasing. It is important to understand both the benefits and the problems of an increase in transportation speed. For bulk commodities, of course, economics still favors transport by large, slow-moving vessels. Speed is not the only criterion; price is also a factor. The Value of Time
For passenger travel, the value that a person puts on his or her time has a major influence on his choice of transportation mode. It can be said that there is a time value implicit in making a modal choice, but this can change with the purpose of the trip and the time at which the trip is made. Reuben Gronau’s study shows that a business traveler’s value-of-time is distributed between half and double the hourly earning rate, and that personal travel has a much lower value, probably between zero and a quarter of the potential rate. 1 The value of time can be treated in a more general manner, particularly in personal travel. Taking a philosophical approach, an individual has a finite lifespan. Teruo Morita received his Bachelor? andMaster’s degrees from the University of Tokyo, Japan, in 1976 and 1978, and his Master of Science degree in Transportation from the Massachusetts Institute of TecbnoLogy in December of 1983. He is now on the staff of the Japanese Nation& Railways. 141
Teruo Morda
142
This lifespan has worth to him. In each culture, the individual has a particular pace at which he wishes to live his life. His lifespan is a limited resource which must be allocated between those activities that he has to do and those that he prefers to do. His activities are related to his potential earning rate, so his and his family’s time can have some value. This implicit value is almost impossible to assess directly and can best be arrived at by establishing how people use their leisure time and by what modes of transportation they do, in fact, travel. In any event, there is a demonstrable relationship between the earning rate and the value-of-time. If there is an increase in the value-of-time, the share of the faster mode of transport will be increased. This is the trend at present. Passengers will choose the transit mode that offers the faster speed and the cheaper travel time, even though the cost of the travel itself is higher. As the value-of-time depends upon an individual’s earning rate, people at the lower levels of income-such as students-tend to have lower values-of-time, while people at higher levels-such as lawyers, doctors, and high-level people in government, business and industry-have higher values-oftime. It is interesting to note that an increase in income is followed by a relatively higher increase in the amount spent on transportation. Figure 1 shows that additional income is spent on transport to a high degree. Table 1 shows the increasing share of transport expenditure in European countries.’ Speed Transport systems tend to become faster and faster in the course of their development. The problems of moving ever-increasing numbers of people from place to place rapidly and frequently are now becoming so acute as to demand increasing attention in all the developed countries of the world. The number of kilometers covered and the frequency of travel are increasing, and passengers increasingly have less time to spare. On some routes, the railroad of today can take passengers away from the airlines if they increase their speed significantly. But speed cannot be separated from other major factors. For example, high speed
TABLE 1. Expenditure on Transport as Percentage of Total Consumer Expenditures
West Germany France
Italy Holland Belgium Luxemberg United Kingdom Ireland Denmark
1970
1974
1976
11.7 10.6 10.7 9.4 10.4 10.9 12.7 9.5 12.2
11.3 10.8 10.9 9.9 10.9 12.7 13.5 10.6 11.5
13.4 12.9 12.1 10.9 11.9 14.2 13.6 11.0 15.4
Source: 0. Hoist, European Transport: Crucial P&/ems Research Needs: a Long-Tern Analysis, 1982, p. 18.
and
143
High Speed Ground Transportation
100
0
Average
Source:
0.
iiolst,
and p.
weekly
200 household
EuroDean -P,esearch Needs:
300
expenditure
Transport: a Long-Term
Crucial
($1
Problems
Analysis,
1982,
18.
FIGURE 1. Household Expenditures on Transport
often implies also higher capital and other operating costs, higher noise levels, and higher energy consumption. This is the reason why some transport modes have reduced their speed, even though they are capable of going faster. When the speed of a particular mode of transit is discussed, these other major factors should not be ignored. Speed
of Inter- City Transportation
There are various procedures that are used to determine and to assess the traveling time for the passengers among the various modes of transport. This paper, however, will concern itself with high speed transportation between cities, especially
Term Monka
144
between conurbanations. The distance between terminals will be between 50 and 500 kilometers, and the maximum distance will be about 1,500 kilometers. National transportation in the US, such as in the Northeast Corridor; national and international transportation in Europe; and national transportation in Japan are good examples. If the average traveling speed of new high-speed transit is higher than that of airplanes, then many passengers may be inclined to use the new transportation, although they will need to take into consideration fare levels, service, safety, and so on. Use
of
Underground
Space
One principal method of high-speed transportation would be the tube vehicle mode, which is still in the experimental stage. This system, however, has many legal aspects which need to be assessed. “Fee simple” ownership of land has included rights to underground space under common law precedent in the US and some other countries. Assignment of surface rights among various individuals or institutions has, therefore, determined the ownership of underground space. The permission of the owner is necessary for the use of such space. Valuable resources, including mining and water rights deep under the surface, are thus subject to ownership by the “fee simple” title holder under the law prevailing in many jurisdictions.3 It has recently been suggested, however, that underground space should be classified with historic common property resources, such as air and water. Historically, air and water cannot be privately owned, because they are subject to private rights to a greater extent than is the land surface itself. From the viewpoint of public policy, it can be argued that underground use should be encouraged in order to protect the amenity values of the surface; a private property regime should encourage the balanced and efficient use of resources. Thus, more extensive use of underground rights can take place within a private property regime, unless there is a compelling public need justifying government regulation or ownership in specific cases. New tunneling technology can reduce the cost of underground construction, but it may not be a sufficient advantage. The new technology may, nevertheless, be sufficient to spur a change in law, if technological advances can dig deep tunnels at economical costs. Changes in law may also facilitate the more economical acquisition of essential rights-of-way. Few Environmental
Costs
Except for minimal interference with mineral and water rights (resources) in some places, deep tunneling should result in few environmental costs. Even if deep spaces were used for storage, a transit tube running through the storage area would not take much space. Under conventional law, the value taken from a landowner for such a deep underground easement would be minimal. If deep underground space were in the public domain, the case of underground easements could be reduced to zero, but this is not likely except in sections of the US still in the public domain. If any mineral rights (resources) were affected, compensation would have to be paid. If the new tube led to ground subsidence, any damage to property would have to be
High Speed Ground Transportation
14,
paid for, but these problems would be minimized by deep tunneling in hard rock. If rights to underground transit (the tube vehicle system) are authorized by state and federal governments, there will be other questions: where the depth line should be drawn, for example. Final decisions as to depth and route will, therefore, involve a “mix” of legal, geological, environmental, engineering and political considerations. Technology
of High Speed
Ground
Transportation
At present, the advanced conventional railways, such as the TGV and the Shinkansen, are operated at a maximum speed of more than 200 kilometers per hour. The TGV is now operated at a maximum speed of 270 kilometers per hour, and is the fastest conventional railway service in the world. But it is very difficult for such services to be operated at an average speed of 400 kilometers per hour (the requirement for HSGT), because of the evident requirements and constraints. It is, therefore, necessary to study other new technologies that will make it feasible to reach average speeds of this velocity. Air-cushion vehicle systems, MAGLEV systems, and tube vehicle systems have good possibilities of attaining such speeds, although there also some undeniable requirements and constraints. In particular, MAGLEV systems will be the most suitable for HSGT development in the near future. The MAGLEV
System
It was circa 1962 that the research and development began on a new inter-city transportation system as a successor to the Shinkansen. It was to be faster and less liable to cause environmental pollution than the Shinkansen. In the early stages, development efforts were focused on the short-stator linear induction motor (LIM) -that is, a system that located the powered “stator” on the vehicle and the reaction rail (or plate) on the track.4 In 1972, an experiment was carried out with a test vehicle (ML-loo), which combined the LIM and the magnetic levitation system based on a repulsion force induced by superconducting magnets. This experiment was conducted on a 480-meter track with an inverted T-shaped guideway at the Railroad Technical Research Institute in Tokyo. As the work progressed, however, it became clear that the long stator linear synchronous motor (the LSM) would be more compatible with electrodynamic levitation. Studies continued on the design of lightweight compact superconducting magnets for both the levitation and the propulsion of the vehicle. Research was also conducted on the guideway, train control devices, braking devices, vehicle structure, and so forth. The Miyazaki full-scale test track was constructed with the support of several agencies of the Japanese government, including the Ministry of Transport, in 1977. A test vehicle, ML-500, started to run on an inverted T-shaped guideway seven kilometers long. In 1979, it attained the high-speed running record of 5 17 kilometers per hour, breaking the previous world record of 428 kilometers per hour achieved by Aerotrain of France. With this achievement, the ML-500 was able to verify the technical possibility of
146
Temo Moda
the superconducting magnet repulsion levitation system and the LSM propulsion system. For the next step, a U-shaped guideway was adopted, since it has the following features: 0 0 0 0 0 0
the construction of the vehicle chassis is simple; the height of the vehicle can be reduced to decrease air resistance and the effects of sidewinds and thus provide better stability; rolling stability is better; equipment can be mounted under the floor; the center of gravity can be lowered; and additional space accommodating passengers can be acquired.5
A recent total for the amount of research and development tem is $2.5~$5 .OO million per year.
for the MAGLEV sys-
The Technology
An outline of the U-shaped facilities, the operational test vehicle facilities will convey some understanding nology.
control equipment, and the of current MAGLEV tech-
Guideway
The guideway is a U-shaped ferro-concrete construction with a running way and side walls on both left and right sides. Side walls are provided with sufficient strength to resist the pressures exerted by auxiliary guide wheels. Figure 2 shows the crosssection of the U-shaped guideway and the vehicle (MLU OOl), which will be described later. The ground coil is hollow, being installed at a pitch that allows for propulsion and guidance on both sides, and levitation on the running way. For the propulsion and guidance coil, the electric power is supplied from the power supply device at the substation via feeder. On the other hand, the levitation coil is designed as a closed loop.’ When the vehicle deviates toward either the left or the right side, a current circulates in the coils for propulsion and guidance. The interaction of forces between this circulating current and the on-board superconducting magnet brings the vehicle back to the center. This is null flux guidance. Operational
Control Equipment
The centralized operational control equipment is installed at the Test Center Building. It controls the vehicle by continuously calculating the values of the parameters of the electric current to be transmitted to the linear motor, and transmitting those values to the substation, so that the vehicle speed will follow the programmed profile. It also constantly monitors the condition of the moving vehicle and automati-
147
High Speed Ground Tramportation
tally transmits for braking.’
instructions
for changing
the positions of the auxiliary wheels and
Vehicle The MLU 00 1 is designed for a three-vehicle formation. An important consideration for the high-speed vehicle is to make it light; the running gear will be aluminum alloy, the car body a sandwich construction of high-strength aluminum, and the car body floor of aluminum honeycomb construction. Each car will carry 32 passengers. Levitation, Propulsion and Guidance (Superconducting Magnets) The superconducting magnets mounted on the MLU 001 have an I-shaped crosssection, and are vertically installed on the left and right sides of the running gear, as shown in Figure 2. They perform the functions of levitation, propulsion and guidance. Weight decrease and power increase are effected in this magnet. Tube Vehicle Systems Dr. Robert M. Salter has studied “Planetran,” which travels at thousands of kilometers per hour in underground evacuated tubes, and is electromagnetically propelled and supported. The Planetran is designed to cross the US in an hour or so,
Helium refrigerator iqutfied hdum tank lnductrve wires
Source
:
Railway
Gazette
on with
MaRlev
International, Trials,
August
JNR Presses 1981,
FIGURE 2. Cross-Section of U-shaped Guideway and MLU 001
p.
648.
148
Teruo Monka
and, therefore, clearly exceeds airplane speeds. As it does not need to climb to high altitudes as airplanes do, its travel time is even further reduced. Theoretically, by means of evacuated tubes and electromagnetic propulsion and suspension, the vehicle speed could be increased to more than 20,000 kilometers per hour. For example, the maximum speed is 22,400 kilometers per hour, if the vehicle runs from Los Angeles to New York without intermediate stops. The travel time is only 2 1 minutes, but passenger comfort needs to be considered, so in actual practice, the run would probably take longer. Although these very high speeds are not necessary for inter-city travel in Europe and Japan, the concept of the Planetran is very useful for general evacuated tube systems. Planetran’s evacuated tubes can be placed above ground, but it is better to go underground to a solid rock formation. The vehicles should be long and narrow to minimize the tube size for reasons of cost and for efficiency of tunneling, tunneling packing, vacuum pumping and electromagnetic propulsion. The air pressure in the tube is reduced to . 1% of sea level; this level of vacuum is not difficult to obtain by usual roughing pumps, and aerodynamic drag loss would be negligible. Quick-opening, computer-controlled gates (or valves) at the ends of the tubes; tube vacuum pumping and sealing systems; and emergency control systems are important for these tube vehicles.8 A multiple vacuum lock system at tunnel ends for entering vehicles has been considered. Giant guillotine doors seal the vehicle in locks of ever-decreasing (or -increasing) pressure served by high-speed roughing pumps to establish proper vacuum conditions between vehicle passages. The doors are started in motion for opening before car arrival and closing before car departure. In order to reduce longitudinal airflow, airbag-like attachments partially inflate in the tube. Further, these attachments fully inflate in the tube in case of an emergency stop. Possibility of Real’ization
Linear electric motor propulsion is the most practical tube vehicle systems, because it is useful for the HSGT lometers per hour, and it has already been developed. tube, HSGT at this speed will soon be a reality. If the ated tube, the speed of the MAGLEV can be greatly aerodynamic drag.
system for several kinds of at a speed of 400 to 500 kiIf the MAGLEV runs in a MAGLEV runs in an evacuincreased in the absence of
After reviewing both the technologies that are - or soon will be - available, and the various potential markets, the objective observer will have to be wary of oversimplifications and generalizations. Each route presents its own specific demands. It is necessary to assess, in each case, the full range of elements that will influence the decision process. This implies thorough analyses of technological, environmental, economic, social, legal, political, and even psychological factors. Developers of the HSGT are confronted, therefore, with the difficult task of
High Speed Ground Transportation
149
assessing the subtle interactions of people and events. Perhaps the best approach to this is to patiently proceed with a case-by-case study and analysis to determine the best way for them to proceed. Notes 1. William S. McLaren and Barry B. Myers, Guided Ground Transportation Study (Montreal: Canadair Limited, 1971). 2. 0. Hoist, European Transport: Crucia/ Problems and Research Needs: A Long-Term Analysis (Luxembourg: Commission of the European Communities, 1982). 3. A. Dan Tarlock, “Legal Aspects of the Use of the Underground” in Legal, Economic, andEnergy Considerationr in the Use of Underground Space (Virginia: National Technical Information Service, US Department of Commerce, 1974). 4. Yoshihiro Kyotani, “In Issuing a Special Edition on Levitated Transportation” injapanese RailwayEngineenrzg 19: 1 (Tokyo: Japan Railway Engineers’ Association, 1979). 5. Japanese Railway Information, “Development of Magnetic Levitation Railway” in Raifway Systems and Components (Tokyo: Japan Rolling Stock Exporters Association, 1981). 6. Mitsugu Sasaki, “Development of the Magnetically Levitated Train” in Japanese Railway Engineering 22:4 (Tokyo: Japan Railway Engineers’ Association, 1983). 7. Japan National Railways, MAGLEV: Transportation for Tomorrow (Tokyo: JNR Press, 1983). 8. Robert M. Salter, “Transplanetary Subway Systems” in Frank P. Davidson, L.J. Giacoletto and Robert Salkeld, eds., Macro-Engineering and the Injktructure of Tomorrow (Boulder, CO: Westview Press, 1978).
0160-791X/84$3.00
+
.OO
Copyright o 1984 Petgamon Press Ltd
High Speed Ground Transportation Some Current and Future Alternatives Terz+!oModa
ABSTRACT. High-speed transportation, the value of time, and the socia/ and technological’considerations of inter-city transportation wi’l be discussedin this article. A particularly promising mode of high-speedground transportation (MAGLEI/;) wi’l be discussed in some detail’. An average speedfor HSGTservice, 400 Rilbmetersper hour, seems to be attainabLe for reasons that wi’l be set forth. In conclusion, the proposal for a “hypersonic” subway wil’l be anaLyzea’.
When there are several modes of transport between a place of origin and a destination, it is not necessary for all travelers to choose the fastest one. But, throughout history- whether a person has been traveling by land, sea or air-speed has always been at a premium, and has been a major influence in the choice of means of transportation. Slower modes of transport have been eliminated, and faster ones introduced; thus the average speed of all methods has been increasing. It is important to understand both the benefits and the problems of an increase in transportation speed. For bulk commodities, of course, economics still favors transport by large, slow-moving vessels. Speed is not the only criterion; price is also a factor. The Value of Time
For passenger travel, the value that a person puts on his or her time has a major influence on his choice of transportation mode. It can be said that there is a time value implicit in making a modal choice, but this can change with the purpose of the trip and the time at which the trip is made. Reuben Gronau’s study shows that a business traveler’s value-of-time is distributed between half and double the hourly earning rate, and that personal travel has a much lower value, probably between zero and a quarter of the potential rate. 1 The value of time can be treated in a more general manner, particularly in personal travel. Taking a philosophical approach, an individual has a finite lifespan. Teruo Morita received his Bachelor? andMaster’s degrees from the University of Tokyo, Japan, in 1976 and 1978, and his Master of Science degree in Transportation from the Massachusetts Institute of TecbnoLogy in December of 1983. He is now on the staff of the Japanese Nation& Railways. 141
Teruo Morda
142
This lifespan has worth to him. In each culture, the individual has a particular pace at which he wishes to live his life. His lifespan is a limited resource which must be allocated between those activities that he has to do and those that he prefers to do. His activities are related to his potential earning rate, so his and his family’s time can have some value. This implicit value is almost impossible to assess directly and can best be arrived at by establishing how people use their leisure time and by what modes of transportation they do, in fact, travel. In any event, there is a demonstrable relationship between the earning rate and the value-of-time. If there is an increase in the value-of-time, the share of the faster mode of transport will be increased. This is the trend at present. Passengers will choose the transit mode that offers the faster speed and the cheaper travel time, even though the cost of the travel itself is higher. As the value-of-time depends upon an individual’s earning rate, people at the lower levels of income-such as students-tend to have lower values-of-time, while people at higher levels-such as lawyers, doctors, and high-level people in government, business and industry-have higher values-oftime. It is interesting to note that an increase in income is followed by a relatively higher increase in the amount spent on transportation. Figure 1 shows that additional income is spent on transport to a high degree. Table 1 shows the increasing share of transport expenditure in European countries.’ Speed Transport systems tend to become faster and faster in the course of their development. The problems of moving ever-increasing numbers of people from place to place rapidly and frequently are now becoming so acute as to demand increasing attention in all the developed countries of the world. The number of kilometers covered and the frequency of travel are increasing, and passengers increasingly have less time to spare. On some routes, the railroad of today can take passengers away from the airlines if they increase their speed significantly. But speed cannot be separated from other major factors. For example, high speed
TABLE 1. Expenditure on Transport as Percentage of Total Consumer Expenditures
West Germany France
Italy Holland Belgium Luxemberg United Kingdom Ireland Denmark
1970
1974
1976
11.7 10.6 10.7 9.4 10.4 10.9 12.7 9.5 12.2
11.3 10.8 10.9 9.9 10.9 12.7 13.5 10.6 11.5
13.4 12.9 12.1 10.9 11.9 14.2 13.6 11.0 15.4
Source: 0. Hoist, European Transport: Crucial P&/ems Research Needs: a Long-Tern Analysis, 1982, p. 18.
and
143
High Speed Ground Transportation
100
0
Average
Source:
0.
iiolst,
and p.
weekly
200 household
EuroDean -P,esearch Needs:
300
expenditure
Transport: a Long-Term
Crucial
($1
Problems
Analysis,
1982,
18.
FIGURE 1. Household Expenditures on Transport
often implies also higher capital and other operating costs, higher noise levels, and higher energy consumption. This is the reason why some transport modes have reduced their speed, even though they are capable of going faster. When the speed of a particular mode of transit is discussed, these other major factors should not be ignored. Speed
of Inter- City Transportation
There are various procedures that are used to determine and to assess the traveling time for the passengers among the various modes of transport. This paper, however, will concern itself with high speed transportation between cities, especially
Term Monka
144
between conurbanations. The distance between terminals will be between 50 and 500 kilometers, and the maximum distance will be about 1,500 kilometers. National transportation in the US, such as in the Northeast Corridor; national and international transportation in Europe; and national transportation in Japan are good examples. If the average traveling speed of new high-speed transit is higher than that of airplanes, then many passengers may be inclined to use the new transportation, although they will need to take into consideration fare levels, service, safety, and so on. Use
of
Underground
Space
One principal method of high-speed transportation would be the tube vehicle mode, which is still in the experimental stage. This system, however, has many legal aspects which need to be assessed. “Fee simple” ownership of land has included rights to underground space under common law precedent in the US and some other countries. Assignment of surface rights among various individuals or institutions has, therefore, determined the ownership of underground space. The permission of the owner is necessary for the use of such space. Valuable resources, including mining and water rights deep under the surface, are thus subject to ownership by the “fee simple” title holder under the law prevailing in many jurisdictions.3 It has recently been suggested, however, that underground space should be classified with historic common property resources, such as air and water. Historically, air and water cannot be privately owned, because they are subject to private rights to a greater extent than is the land surface itself. From the viewpoint of public policy, it can be argued that underground use should be encouraged in order to protect the amenity values of the surface; a private property regime should encourage the balanced and efficient use of resources. Thus, more extensive use of underground rights can take place within a private property regime, unless there is a compelling public need justifying government regulation or ownership in specific cases. New tunneling technology can reduce the cost of underground construction, but it may not be a sufficient advantage. The new technology may, nevertheless, be sufficient to spur a change in law, if technological advances can dig deep tunnels at economical costs. Changes in law may also facilitate the more economical acquisition of essential rights-of-way. Few Environmental
Costs
Except for minimal interference with mineral and water rights (resources) in some places, deep tunneling should result in few environmental costs. Even if deep spaces were used for storage, a transit tube running through the storage area would not take much space. Under conventional law, the value taken from a landowner for such a deep underground easement would be minimal. If deep underground space were in the public domain, the case of underground easements could be reduced to zero, but this is not likely except in sections of the US still in the public domain. If any mineral rights (resources) were affected, compensation would have to be paid. If the new tube led to ground subsidence, any damage to property would have to be
High Speed Ground Transportation
14,
paid for, but these problems would be minimized by deep tunneling in hard rock. If rights to underground transit (the tube vehicle system) are authorized by state and federal governments, there will be other questions: where the depth line should be drawn, for example. Final decisions as to depth and route will, therefore, involve a “mix” of legal, geological, environmental, engineering and political considerations. Technology
of High Speed
Ground
Transportation
At present, the advanced conventional railways, such as the TGV and the Shinkansen, are operated at a maximum speed of more than 200 kilometers per hour. The TGV is now operated at a maximum speed of 270 kilometers per hour, and is the fastest conventional railway service in the world. But it is very difficult for such services to be operated at an average speed of 400 kilometers per hour (the requirement for HSGT), because of the evident requirements and constraints. It is, therefore, necessary to study other new technologies that will make it feasible to reach average speeds of this velocity. Air-cushion vehicle systems, MAGLEV systems, and tube vehicle systems have good possibilities of attaining such speeds, although there also some undeniable requirements and constraints. In particular, MAGLEV systems will be the most suitable for HSGT development in the near future. The MAGLEV
System
It was circa 1962 that the research and development began on a new inter-city transportation system as a successor to the Shinkansen. It was to be faster and less liable to cause environmental pollution than the Shinkansen. In the early stages, development efforts were focused on the short-stator linear induction motor (LIM) -that is, a system that located the powered “stator” on the vehicle and the reaction rail (or plate) on the track.4 In 1972, an experiment was carried out with a test vehicle (ML-loo), which combined the LIM and the magnetic levitation system based on a repulsion force induced by superconducting magnets. This experiment was conducted on a 480-meter track with an inverted T-shaped guideway at the Railroad Technical Research Institute in Tokyo. As the work progressed, however, it became clear that the long stator linear synchronous motor (the LSM) would be more compatible with electrodynamic levitation. Studies continued on the design of lightweight compact superconducting magnets for both the levitation and the propulsion of the vehicle. Research was also conducted on the guideway, train control devices, braking devices, vehicle structure, and so forth. The Miyazaki full-scale test track was constructed with the support of several agencies of the Japanese government, including the Ministry of Transport, in 1977. A test vehicle, ML-500, started to run on an inverted T-shaped guideway seven kilometers long. In 1979, it attained the high-speed running record of 5 17 kilometers per hour, breaking the previous world record of 428 kilometers per hour achieved by Aerotrain of France. With this achievement, the ML-500 was able to verify the technical possibility of
146
Temo Moda
the superconducting magnet repulsion levitation system and the LSM propulsion system. For the next step, a U-shaped guideway was adopted, since it has the following features: 0 0 0 0 0 0
the construction of the vehicle chassis is simple; the height of the vehicle can be reduced to decrease air resistance and the effects of sidewinds and thus provide better stability; rolling stability is better; equipment can be mounted under the floor; the center of gravity can be lowered; and additional space accommodating passengers can be acquired.5
A recent total for the amount of research and development tem is $2.5~$5 .OO million per year.
for the MAGLEV sys-
The Technology
An outline of the U-shaped facilities, the operational test vehicle facilities will convey some understanding nology.
control equipment, and the of current MAGLEV tech-
Guideway
The guideway is a U-shaped ferro-concrete construction with a running way and side walls on both left and right sides. Side walls are provided with sufficient strength to resist the pressures exerted by auxiliary guide wheels. Figure 2 shows the crosssection of the U-shaped guideway and the vehicle (MLU OOl), which will be described later. The ground coil is hollow, being installed at a pitch that allows for propulsion and guidance on both sides, and levitation on the running way. For the propulsion and guidance coil, the electric power is supplied from the power supply device at the substation via feeder. On the other hand, the levitation coil is designed as a closed loop.’ When the vehicle deviates toward either the left or the right side, a current circulates in the coils for propulsion and guidance. The interaction of forces between this circulating current and the on-board superconducting magnet brings the vehicle back to the center. This is null flux guidance. Operational
Control Equipment
The centralized operational control equipment is installed at the Test Center Building. It controls the vehicle by continuously calculating the values of the parameters of the electric current to be transmitted to the linear motor, and transmitting those values to the substation, so that the vehicle speed will follow the programmed profile. It also constantly monitors the condition of the moving vehicle and automati-
147
High Speed Ground Tramportation
tally transmits for braking.’
instructions
for changing
the positions of the auxiliary wheels and
Vehicle The MLU 00 1 is designed for a three-vehicle formation. An important consideration for the high-speed vehicle is to make it light; the running gear will be aluminum alloy, the car body a sandwich construction of high-strength aluminum, and the car body floor of aluminum honeycomb construction. Each car will carry 32 passengers. Levitation, Propulsion and Guidance (Superconducting Magnets) The superconducting magnets mounted on the MLU 001 have an I-shaped crosssection, and are vertically installed on the left and right sides of the running gear, as shown in Figure 2. They perform the functions of levitation, propulsion and guidance. Weight decrease and power increase are effected in this magnet. Tube Vehicle Systems Dr. Robert M. Salter has studied “Planetran,” which travels at thousands of kilometers per hour in underground evacuated tubes, and is electromagnetically propelled and supported. The Planetran is designed to cross the US in an hour or so,
Helium refrigerator iqutfied hdum tank lnductrve wires
Source
:
Railway
Gazette
on with
MaRlev
International, Trials,
August
JNR Presses 1981,
FIGURE 2. Cross-Section of U-shaped Guideway and MLU 001
p.
648.
148
Teruo Monka
and, therefore, clearly exceeds airplane speeds. As it does not need to climb to high altitudes as airplanes do, its travel time is even further reduced. Theoretically, by means of evacuated tubes and electromagnetic propulsion and suspension, the vehicle speed could be increased to more than 20,000 kilometers per hour. For example, the maximum speed is 22,400 kilometers per hour, if the vehicle runs from Los Angeles to New York without intermediate stops. The travel time is only 2 1 minutes, but passenger comfort needs to be considered, so in actual practice, the run would probably take longer. Although these very high speeds are not necessary for inter-city travel in Europe and Japan, the concept of the Planetran is very useful for general evacuated tube systems. Planetran’s evacuated tubes can be placed above ground, but it is better to go underground to a solid rock formation. The vehicles should be long and narrow to minimize the tube size for reasons of cost and for efficiency of tunneling, tunneling packing, vacuum pumping and electromagnetic propulsion. The air pressure in the tube is reduced to . 1% of sea level; this level of vacuum is not difficult to obtain by usual roughing pumps, and aerodynamic drag loss would be negligible. Quick-opening, computer-controlled gates (or valves) at the ends of the tubes; tube vacuum pumping and sealing systems; and emergency control systems are important for these tube vehicles.8 A multiple vacuum lock system at tunnel ends for entering vehicles has been considered. Giant guillotine doors seal the vehicle in locks of ever-decreasing (or -increasing) pressure served by high-speed roughing pumps to establish proper vacuum conditions between vehicle passages. The doors are started in motion for opening before car arrival and closing before car departure. In order to reduce longitudinal airflow, airbag-like attachments partially inflate in the tube. Further, these attachments fully inflate in the tube in case of an emergency stop. Possibility of Real’ization
Linear electric motor propulsion is the most practical tube vehicle systems, because it is useful for the HSGT lometers per hour, and it has already been developed. tube, HSGT at this speed will soon be a reality. If the ated tube, the speed of the MAGLEV can be greatly aerodynamic drag.
system for several kinds of at a speed of 400 to 500 kiIf the MAGLEV runs in a MAGLEV runs in an evacuincreased in the absence of
After reviewing both the technologies that are - or soon will be - available, and the various potential markets, the objective observer will have to be wary of oversimplifications and generalizations. Each route presents its own specific demands. It is necessary to assess, in each case, the full range of elements that will influence the decision process. This implies thorough analyses of technological, environmental, economic, social, legal, political, and even psychological factors. Developers of the HSGT are confronted, therefore, with the difficult task of
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assessing the subtle interactions of people and events. Perhaps the best approach to this is to patiently proceed with a case-by-case study and analysis to determine the best way for them to proceed. Notes 1. William S. McLaren and Barry B. Myers, Guided Ground Transportation Study (Montreal: Canadair Limited, 1971). 2. 0. Hoist, European Transport: Crucia/ Problems and Research Needs: A Long-Term Analysis (Luxembourg: Commission of the European Communities, 1982). 3. A. Dan Tarlock, “Legal Aspects of the Use of the Underground” in Legal, Economic, andEnergy Considerationr in the Use of Underground Space (Virginia: National Technical Information Service, US Department of Commerce, 1974). 4. Yoshihiro Kyotani, “In Issuing a Special Edition on Levitated Transportation” injapanese RailwayEngineenrzg 19: 1 (Tokyo: Japan Railway Engineers’ Association, 1979). 5. Japanese Railway Information, “Development of Magnetic Levitation Railway” in Raifway Systems and Components (Tokyo: Japan Rolling Stock Exporters Association, 1981). 6. Mitsugu Sasaki, “Development of the Magnetically Levitated Train” in Japanese Railway Engineering 22:4 (Tokyo: Japan Railway Engineers’ Association, 1983). 7. Japan National Railways, MAGLEV: Transportation for Tomorrow (Tokyo: JNR Press, 1983). 8. Robert M. Salter, “Transplanetary Subway Systems” in Frank P. Davidson, L.J. Giacoletto and Robert Salkeld, eds., Macro-Engineering and the Injktructure of Tomorrow (Boulder, CO: Westview Press, 1978).