Seminar Report on

MAGNETIC LEVITATION TRAIN TECHNOLOGY

DEPARTMENT OF ELECTRICAL ENGINEERING

NATIONAL INSTITUTE OF TECHNOLOGY KURUKSHETRA

In Partial fulfilment for the award of degree in

Bachelor of Technology
Electrical Engineering

Under the Guidance of

Dr. Rupanshi Batra
Electrical Engineering Department

Submitted By
Sunil Kumar Meena
EE C 09
12014070
 ABSTRACT

This seminar report explores the cutting-edge developments in

Magnetic Levitation (Maglev) train technology, a revolutionary mode of
transportation that relies on magnetic forces to achieve frictionless, high-
speed travel. The report delves into the fundamental principles of Maglev
propulsion, elucidating the magnetic levitation and propulsion systems that
enable these trains to hover above the tracks and reach unprecedented
speeds. It highlights the environmental benefits, energy efficiency, and
safety features of Maglev trains, positioning them as a sustainable solution
for the future of transportation. The report also discusses notable Maglev
projects around the world, shedding light on their successes and challenges.
Attendees will gain insights into the transformative potential of Maglev
technology and its implications for the evolution of modern transportation
systems.

ii
 Table of Contents
1) Introduction 1

2) Development of Maglev and Hyperloop Systems 3

2.1) Conceptual Development 3

3) Theory and Technology 5

3.1) Support 6

3.2) Guidance 11

3.3) Propulsion and Braking 15

3.5) Summary and Comparison 19

4) Applications 20

5) Benefits of Maglev 20

6) Drawbacks of Maglev 22

7) Electrical Engineering in Maglev 23

8) The Future of Maglev 24

9) References 24

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1) Introduction
The rail transport system features rails and wheels. Because of this, the railway
system heavily relies on adhesion at the rail-wheel interface to provide guidance,
propulsion and braking force. Rails and wheels are relatively stiff and their interaction
can result in a series of technical issues related to adhesion, rail-wheel wear, power
transmission, noise and vibration, maintenance cost, etc. These issues become more
and more significant with increasing speed and are limiting factors to a further increase
in operational speed. Even though a French TGV test train proved that a conventional
rail-wheel based train can achieve a maximum speed of 574 km/h, the mentioned
technical issues still restrict the application of conventional rail-wheel trains for very
high-speed operation in daily commercial operation. In response to these technical
limitations some new types of guided transport systems, which do not rely on the rails
and wheels, e.g. maglev systems and hyperloop systems, are being developed or have
even been used/built, as shown in Figure 1.

Figure 1(a): Japanese L0 Series Maglev Train Figure 1(b): Chinese HTS Maglev Train

Figure 1(c): German Trans Rapid Maglev Train Figure 1(d): US Virgin Hyperloop One
Operated in Shanghai

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 In order to achieve a very high operational speed, in maglev and hyperloop
systems the moving vehicles are levitated and propelled from the guideway by
magnetic forces. Since there is no direct physical contact between the moving train and
the guideway during operation, the speed is no longer restricted by technical problems
linked to the rail-wheel interaction. There are no rotational and sliding components on
the moving maglev trains, e.g., wheels, bearings, axles, motors, gears and pantograph,
so the rolling resistance and dynamic load are smaller than for conventional trains
running at the same speed. Without rotational and sliding components, the
corresponding maintenance and reliability, therefore, are improved. Maglev systems
are supposed to have higher operational speeds, lower energy consumption, less life
cycle costs, less noise and vibration than high-speed trains. However, the aerodynamic
drag increases with the square of the speed, so it becomes more and more significant
with the increase of the running speed of the train. Although maglev trains have very
low rolling resistance and have a streamlined design which can lower the aerodynamic
drag, the aerodynamic drag plays the dominating role the very-high-speed operation.
In order to overcome the aerodynamic drag at very high-speed operation, hyperloop
designs are proposed, where the vehicle/pod with passengers runs inside a large sealed
and low-pressurized tube, and boarding and alighting are handled in special terminals.
There are many ways to classify maglev systems, e.g. by suspension system,
traction system, magnetic system, and operational speed. The common way is to
classify the maglev systems according to the operational speed. They can be classified
as: low-speed maglev systems (below 100 km/h), medium-speed maglev systems
(between 100 km/h and 200 km/h), high-speed maglev systems (between 200 km/h and
600 km/h) and very-high-speed maglev systems (above 600 km/h). The low-speed and
medium-speed systems are designed for mass transport in urban and suburban areas.
The high-speed systems are for intercity travels within the medium and long-distance.

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2) Development of Maglev and Hyperloop Systems

2.1) Conceptual Development

The concept of the maglev system started in the early 1900s. High-speed
transportation patents were granted to various inventors throughout the world at the
beginning of the 20th century. In 1905 United States patents for a linear motor
propelled train were awarded to the German inventor Alfred Zehden. In 1908 Tom
Johnson filed a patent for a wheel-less "highspeed railway" levitated by an induced
magnetic field. In 1914, the French-born American inventor Emile Bachelet presented
his idea of a maglev vehicle and even displayed the first model, as shown in Figure 2.1.
He demonstrated a magnetic suspension using repulsive forces generated by alternating
currents, which was the basic idea for electro-dynamic suspension (EDS), but it was
not adopted until the superconducting magnets became available because of the high-
power demand of the electro-dynamic suspension. In 1922 the German researcher
Hermann Kemper pioneered an attractive-model maglev system, which was the basic
idea of electro-magnetic suspension (EMS). Later, between 1934 and 1941, he was
awarded a series of German patents for magnetic levitation trains propelled by a linear
motor.

Figure 2: Emile Bachelet Presenting His Maglev Model

Between 1939 and 1943 German engineers worked on a real train based on
practical attractive mode maglev in Göttingen, which finally was presented in 1953.
An early maglev train was described in a US Patent "Magnetic system of
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transportation" by G.R. Polgreen in 1959. The word "maglev" was used in the US
patent "Magnetic levitation guidance system" for the first time. After the finding of
superconductivity, in 1963 the American researchers Powell and Danby of Brookhaven
National Laboratory realized that superconductivity could be used for the maglev
system. In 1966 they presented their maglev concept of using superconducting magnets
in a vehicle and discrete coils on the guideway, in which the static magnets mounted
on a moving vehicle would induce both electro-dynamic lifting and stabilizing forces
in specially shaped loops, which realized Bachelet’s concept. In 1969, researchers from
Stanford developed a continuous-sheet guideway (CSG) concept, in which the moving
magnetic fields of the vehicle induced currents in a continuous sheet of conducting
material, such as aluminum, to generate a lifting force to the vehicle.
Maglev, a floating vehicle for land transportation that is supported by either
electromagnetic attraction or repulsion. Maglevs were conceptualized during the early
1900s by American professor and inventor Robert Goddard and French-born American
engineer Emile Bachelet and have been in commercial use since 1984, with several
operating at present and extensive networks proposed for the future.
Maglevs incorporate a basic fact about magnetic forces—like magnetic poles repel
each other, and opposite magnetic poles attract each other—to lift, propel, and guide a
vehicle over a track (or guideway). Maglev propulsion and levitation may involve the
use of superconducting materials, electromagnets, diamagnets, and rare-earth magnets.
In 1965 the Department of Commerce established the high-speed Ground
Transportation Act. Most early work on developing Maglev technology was developed
during this time. The earliest work was carried out by the Brookhaven National
Laboratory, Massachusetts Institute of Technology, Ford, Stanford Research Institute,
Rohr Industries, Boeing Aerospace Co., and the Garrett Corporation. In the United
States, though, the work ended in 1975 with the termination of Federal Funding for
high-speed ground transportation and research. It was at that time when the Japanese

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and German developers continued their research and therefore came out with the first
test tracks.
In 1990, legislative action directed the U.S. Army Corps of Engineers to
implement and prepare a plan for a National Maglev program. The Department of
Transportation (DOT), Department of Energy (DOE), and the Army Corp developed
what is known as the National Maglev Initiative which was a two year 25-million-dollar
program to assess the engineering, economic, environmental and safety aspects of
Maglev.

3) Theory and Technology

For any kind of guided transport system, there are three basic functions that have
to be fulfilled :
a) Support

b) Guidance

c) Propulsion and braking

The support is the vertical contact between the vehicle and the running surface.
The guidance relates to the means of steering or lateral motion of the vehicle. The
propulsion and braking are the longitudinal force that propels and stops the movement
of the vehicle. For conventional rail transport systems, the support, guidance, and
propulsion and braking are provided by the rails and wheels. For maglev and hyperloop
systems, the vehicle is elevated from the infrastructure and physical contact between
the vehicles and the infrastructure is avoided and no rotational components are needed,
i.e. the mechanical friction is removed. Therefore, the mechanism of the three basic
functions is totally different from the rail transport systems.
The creation of magnetic forces is the basis of all magnetic levitation. The creation
of a magnetic field can be caused by a number of things. The first thing that it can be
caused by is a permanent magnet. These magnets are a solid material in which there is
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an induced North and South Pole. The second way that a magnetic field can be created
is through an electric field changing linearly with time. The third and final way to create
a magnetic field is through the use of direct current.

3.1) Support
Support is to carry vehicle mass and payload in the vertical direction. For the rail
transport systems, the rail vehicles rest their weight through the steel wheels on the
rails. For some guided transport systems, rubber tires are used and stand on
concrete/steel beams. However, for the maglev and hyperloop systems magnetic
levitation or magnetic suspension is used in which the vehicles are elevated from the
guideway by magnetic force to counteract the gravitational force to realize non-contact
support.
In magnetic levitation, magnetic materials and systems are able to attract or repel
each other with a force dependent on the magnetic field and the area of the magnets.
Magnetic levitation is realized through magnetic fields between magnetic objects.
Electromagnets, permanent magnets and superconductors can be used to generate the
magnetic field in different systems. The maglev and hyperloop systems use these
attractive and repulsive forces to lift the vehicle above the guideway. There are several
engineering approaches for this in maglev and hyperloop systems.
(1) Electro-Magnetic Suspension (EMS)
The electromagnet, which is widely used in magnetic levitation systems, is a type
of magnet in which the magnetic field is produced by an electric current.
Electromagnets usually consist of a large number of closely spaced turns of wire that
create the magnetic field. The wire turns are wound around a magnetic core made from
ferromagnetic materials. When a current passes through a wire, a magnetic field around
that wire is generated. The strength of the generated magnetic field is proportional to
the current through the wire. The magnetic core concentrates the magnetic flux and

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makes a more powerful magnet. The levitation is accomplished based on a magnetic
attractive force between the guideway and electromagnets as shown in Figure 3.1. The
attractive force pulls upwards the undercarriage as well as the carbody of the maglev
train against gravity. The magnetic rail can be made of permanent magnets or
electromagnets. The air gap between the magnetic rail and the electromagnet on the
undercarriage is detected by sensors and controlled by adjusting the input current. The
electromagnetic attractive force is independent of the running speed, so there could be
a constant uplift force even at zero speed. Because the magnitude of the magnetic force
decreases much with the air gap increasing, a small air gap around 10 mm is to be
maintained.
The EMS system has been widely used in engineering applications, e.g. the
Japanese HSST maglev train, the German
Trans rapid maglev train operating in
Shanghai and some low-speed maglev
systems in the world. The main advantage
of an electromagnet over a permanent
magnet is that the magnetic field can be
quickly changed by controlling the
amount of electric current in the winding.
The direction of a magnetic field is
Figure 3.1: Levitation principle of EMS
dependent on the direction of the electric
current. There are also some disadvantages of the EMS. Because the air gap is small
between the vehicle and the infrastructure, the structural misalignment in the
construction and the structural deformation during operation should be kept as small as
possible to maintain the clearance. The electromagnets also consume much electricity
to generate the magnetic field.

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 Once the power supply to the electromagnets is shut down, the levitation stops
working immediately. In addition, simply controlling the position usually leads to
instability, due to the short-time delays in the inductance of the coil and in sensing the
position. In practice, the feedback circuit must use the change of position over time to
determine and damp the vertical velocity.

(2) Electro-Dynamic Suspension (EDS)

While the EMS uses an attractive force, the EDS uses a repulsive force for
levitation. Electrodynamic suspension (EDS) is based on the principle that when the
conductors are exposed to time-varying magnetic fields, these fields (relative
movement between two objects) can induce eddy currents in the conductors that create
a repulsive magnetic field which holds the two objects apart. When the magnets
attached to the trains move forward on the inducing coils or conducting sheets located
on the guideway, the induced currents flow through the coils or sheets and generate the
magnetic field, as shown in Figure 3.2. The trains are elevated by the repulsive force
between the magnetic field on the guideway and the magnets on the train. The magnetic
field on the train is produced by either permanent magnets or superconducting magnets.
The induced magnetic field is generated by wires or other conducting strips on the
track. The magnets and the induced conductors do not need to be mounted below the
carbody but can be mounted on the two sides below the center of gravity of the carbody,
see e.g. the Japanese MLX maglev system.
At low speeds, the current induced in the conductors is not large enough to
produce a sufficient repulsive electromagnetic force to support the weight of the train
due to the slow change in magnetic flux with respect to time. Moreover, the energy
efficiency for EDS at low speed is low. For this reason, the train must have wheels or
some other form of take-off and landing gear to support the train until it reaches a speed
(around 100 km/h) that can sustain levitation. Since a train may stop at any location,
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due to equipment problems, for instance, the entire track must be able to support both
low-speed and high-speed operation. At high speeds, the induced repulsive force
becomes vigorous and stable so that the air gap is increased to around 100 mm and
reliable for the variation of the load, so it is unnecessary to control the air gap and
magnetic field. The air-gap can cope with small and medium structural irregularities or
structural deformations. Therefore, EDS is highly suitable for high-speed operation.
By the magnets on the
trains, the EDS may be divided
into two types: the permanent
magnet (PM) type and the
superconducting magnet (SCM)
type. For the PM type, the
system is relatively simple
because there is no need for a
high electric power supply. But
the PM type is only limited to
applications for small systems Figure 3.2: Levitation Principle of EDS

because there are no high-powered PMs available. For the SCM type, the system is
relatively complex to maintain a very low temperature for super conduction by
evaporation of liquidized helium. Even though the power supply to the vehicle is turned
off, the super-cooled coils can maintain the levitation for a while, which is different
from the EMS. The generated heat of the induced currents may cause problems during
operation. The Japanese MLX maglev system used the EDS design for levitation and
achieved a maximum running speed of 603 km/h in 2015.

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(3) Super Conducting Magnetic Suspension (SMS)
EMS and EDS have been developed and partly put into commercial operation for
many years. In order to elevate the vehicle from the guideway, a complex suspension
system has to be onboard that consumes a great amount of energy. For example, for
EMS, electric energy is continuously needed to magnetize the electromagnets and a
control system is used to maintain the air gap within an acceptable range, while EDS
does not work at low speeds and needs a complex and expensive cooling system for
liquid helium for superconductors (Japanese MLX maglev system). But with the
development of high-temperature superconductors, high temperature ceramic
superconductors that can be cooled by using liquid nitrogen rather than liquid helium
for superconductors, it is possible to use high-temperature superconductors and
permanent magnets to achieve levitation with an inexpensive coolant. The levitation
does not require a control system to maintain the air gap and is not dependent on
running speed (i.e. working at the entire speed range).
According to a design proposal, a permanent magnet guideway (PMG) is used to
provide the applied magnetic field and the high-temperature superconductors are
mounted below the vehicle. The repulsive force between the superconductors and the
permanent magnets can lift up the vehicle from the guideway at any speed (even when
the vehicle is standing still), as shown in Figure 3.3. There is neither energy nor air-gap
control system needed for levitation. The air gap can be maintained at around 10-20
mm (for the Chinese HTSS prototype maglev train).
The HTSS system is under development and has not yet been commercialized up
to now. The advantage of the HTSS system is self-stabilizing levitation without
additional energy consumption. The HTSS system onboard is lighter and simpler than
the EMS and EDS systems.

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 The HTSS system still has some
limitations. First of all, the loading
capacity is still small (supportive force
density of superconductor: ca. 6
N/cm2), and the small air gap requires
small structural misalignments in the
construction and low deformation
during operation. Secondly, the
permanent magnet guideway uses a Figure 3.3: Levitation Principle of HTSS

great number of permanent magnets which is made from rare-earth elements and leads
to a high capital cost of the infrastructure. Lastly, the permanent magnets have a strong
attraction to ferromagnetic metals, so only low-magnetic steel can be used for the
infrastructure. It is very important for a safe and long-term operation to keep the
guideway clear from all kinds of ferromagnetic metal.

3.2) Guidance
Guidance means the lateral steering of the vehicle. For guided transport systems,
the travelling course and the lateral movement of the vehicle are defined and
constrained by the guideway. This distinctive feature makes the guided transport
systems much different from other modes of transport, e.g. cars, airplanes and vessels.
For railway systems, the conicity of the wheels ensures that the solid-axle wheelsets
are self-steering and that the wheel flanges only provide a backup constraint in the
lateral direction. Since maglev and hyperloop systems should also be guided by the
guideway, a reliable guidance mechanism is very important. For maglev and hyperloop
systems, the physical contact between vehicles and guideway is avoided, so a magnetic
force is also used for guidance to counteract the centrifugal force in curves and

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withstand any possible disturbances in the lateral direction. There are three guidance
approaches corresponding to the three types of suspension above.

(1) Electromagnetic Suspension (EMS)

For low-speed maglev systems, both the operational speed is low and the
centrifugal force in curves is small. The EMS is self-centered, which means any lateral
displacement between the magnetic rail and the electromagnet leads to a restoring force
to pull the vehicle back to the center position, as shown in Figure 3.4(a). The magnetic
field can be adjusted to strengthen the restoring force by detecting the air gap.
Therefore, there is no need to have a specific guidance system onboard or in the
infrastructure.

Figure 3.5(a): Restoring Force of Low-Speed EMS Figure 4: Additional Lateral Suspension for
Maglev System for Guidance High-Speed EMS Maglev System

However, for high-speed maglev system, the operational speed, centrifugal force
and dynamic load are very high. In addition, the air gap between the vehicle and the
infrastructure for the EMS system is small, so the restoring force is not strong and fast
enough to center the vehicle back to its original position. In order to acquire a high
restoring force, another electromagnetic suspension is used in the lateral direction, as
shown in Figure 3.4(b). The system works as the EMS for levitation. There are also

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sensors to detect the air gap in the lateral direction to control the electric current through
the electromagnets.

(2) Electro-dynamic suspension (EDS)

As mentioned, the electro-dynamic suspension uses repulsive force for levitation.
The repulsive force is very strong with speed increase and can maintain a large air gap
(clearance) between the infrastructure and the vehicle, so it is not necessary to place
the magnets and the induced conductors right below the carbody. In order to provide
the restoring force in the lateral direction for guidance, the EDS is placed on the two
sides of the vehicle and the induced conductors are a bit below the magnets onboard,
as shown in Figure 3.5. In that case, the same suspension system works for both vertical
levitation and lateral guidance.

Figure 3.5: Electrodynamic Suspension for Guidance

Even though the suspension system becomes simple, as mentioned previously, the
EDS does not work well in the low-speed range, so wheels or a special gear are needed
not only right below the carbody but also on the two sides of the vehicle. In an
emergency condition, they have to take over the EDS system to carry the train weight.
The suspension systems, therefore, become relatively complex.

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(3) Superconducting Magnetic Suspension (SMS)
For the superconducting magnetic suspension (SMS), the superconductors are
mounted onboard and the permanent magnets are used to build the guideway. When
the superconductors are exposed to a magnetic field, the so-called Meissner effect
comes into play, which means that the superconductors oppose any change to the
externally applied magnetic field. For the SMS system, any lateral movement of the
superconductors results in a strong restoring force to withstand the lateral movement,
because the magnetic flux of the permanent magnets becomes small when the distance
between the superconductors and the permanent magnets is increasing apart. Therefore,
the lateral movement of the vehicle is constrained. Since the guideway is built with
identical permanent magnets in the longitudinal direction, the magnetic flux along the
guideway is not changed, so the vehicle can move freely in the longitudinal direction,
as shown in Figure 3.6.

Figure 3.6: Superconducting Magnetic Suspension for Guidance

The effect is a welcomed feature of the SMS, which can directly be used for
guidance without adding another guidance system for the maglev trains. However, the
restoring force is constant and does not increase with speed, so the restoring force of

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the superconductors is not high enough for high-speed operation. Further studies on
SMS are needed before it can be used for commercial applications.

3.3) Propulsion and Braking

The propulsion is the longitudinal force that propels the vehicle. For other kinds
of guided transport systems, the propulsion force is generated at the contact interface
between the moving vehicle and the guideway, e.g. the rail-wheel interface for the
railway systems and the Tyr guideway interface for the rubber-tire trains. The physical
contact between the rotating wheels and the guideway results in rolling resistance and
wear. The adhesion available for the propulsion is not constant but subjected to many
influencing factors, e.g. decreased adhesion at high speeds and at contaminated
surfaces. For maglev and hyperloop systems, the physical contact between the vehicles
and the guideway is avoided, so the magnetic force is also used for the propulsion.
Therefore, there is no rotational component needed. In this sense, the vehicle is no
longer limited by adhesion in traction and many related issues like rolling resistance,
rolling contact fatigue and rail squeal noise. Non-contact linear motors are used for
both traction and braking.
The linear motor is providing the propulsion in maglev and hyperloop systems.
The linear motor is an electric motor which has its stator and rotor "unrolled", thus
instead of producing a torque (rotation) it produces a force along its length, as shown
in Figure 3.7. There are two main types of linear motors used: Linear induction motors
(LIM) and Linear synchronous motors (LSM). For the linear motor, the stator with the
longitudinal moving magnetic field is called primary and the rotor with
induced/constant magnetic field is called secondary. In maglev systems, both the
primary and the secondary can be installed either on the moving vehicle or on the fixed

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guideway, and vice versa. The configuration of the primary and the secondary is
dependent on the installation cost of the guideway.

Figure 7: Function of linear motor

For low-speed maglev systems, a short primary type of linear induction motor is
used. In the system, the primary is installed on the vehicle and the secondary is
aluminum plates (reaction board) on the guideway, as shown in Figure 3.8(a). The
travelling magnetic field of the three-phase winding onboard works as the primary and
can induce eddy-currents and magnetic field in the aluminum plate to propel the vehicle
in the longitudinal direction. The vehicle can either be standing-still or move in the
longitudinal direction and the induced eddy-current is caused by the longitudinal
movement of the magnetic field. The structure of the guideway can therefore be much
simplified, so the capital costs are significantly reduced, as shown in Figure 3.8(b). For
this kind of system, the air gap between the primary and the reaction board should be

Figure 3.8(a): Functionality of Linear induction motor of low-speed maglev systems

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small. Normally, to maintain a constant power supply, current collectors mounted on
the vehicle are in contact with powered rails to get electricity from the infrastructure.
The systems have low energy efficiency and cannot exceed speeds of around 300
km/h because of the current collectors. Realized designs are the Japanese HSST,
Korean UTM and Chinese low speed urban maglev systems.

Figure 3.8(b): Guideway of Low-Speed Maglev Systems in China

For high-speed maglev systems, linear synchronous motors (LSM) are used.
Different from low-speed systems, the primary is on the guideway, so the travelling
magnetic field is realized by the winding on the guideway, as shown in Figure 3.9(a).
Permanent magnets or electromagnets are used for the secondary on the vehicle. During
operation, the secondary closely follows the travelling magnetic field, so there is no
slip between the vehicle and the magnetic field of the primary, as shown in Figure
3.9(b). There is no need for a large amount of electric energy transfer to the vehicle, so
current collectors can be avoided and the system is thus suitable for high-speed
applications. Since the vehicle closely follows the travelling of the magnetic field of
the primary on the guideway, the speed is precisely controlled by the frequency of the
current in the primary. But the construction cost is much higher than for low-speed
systems. Regarding the secondary, the German Trans rapid maglev system uses
electromagnets with iron core and the Japanese MLX maglev system uses
superconducting magnets with air core.

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 Figure 3.910(a): Windings on the Guideway

Figure 3.9(b): Functionality of Linear Synchronous Motor (LSM) in

Japanese MLX High-Speed Maglev System

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3.5) Summary and Comparison
There are many types of suspension systems as mentioned above. The different
features of the suspension systems are summarized and compared in Table 3.1.
Table 3.1: Comparison of Different Types of The Maglev Suspension System

Superconducting
Electro-magnetic Electro-dynamic
Characteristics magnetic
suspension (EMS) suspension (EDS)
suspension (SMS)

Type of mode Attraction force Repulsive force Repulsive force

Iron cored Superconducting

Magnets Superconductor
electromagnets coils

Cooling Not necessary Necessary Necessary

Guideway gap 10-15 mm 100-150 mm 10-20 mm

Guideway Permanent
Laminated strips Aluminum strips
components magnets

Feedback control Necessary Unnecessary Unnecessary

Compatible drive Linear induction Linear Linear

system motor synchronous motor synchronous motor

MLX (Japanese
Example Trans rapid -
L0)

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4) Applications
Six commercial maglev systems are currently in operation around the world. One
is located in Japan, two in South Korea, and three in China. In Aichi, Japan, a system
built for the 2005 World’s Fair, the Linimo, is still in operation. It is about 9 km long,
with nine station stops over that distance, and a maximum speed of about 100 km/h.
The Korean Rotem Maglev runs in the city of Daejeon between the Daejeon Expo Park
and the National Science Museum with a distance of 1 km. The Inchon Airport Maglev
has six stations and runs from Inchŏn International Airport to the Yongyu station, 6.1
km away. The longest commercial maglev system is in Shanghai; it covers about 30
km and runs from the urban area to Pudong International Airport. The line is the first
high-speed commercial maglev, operating at a maximum speed of 430 km/h. China
also has two low-speed maglev systems operating at speeds of 100 km/h. The Changsha
maglev connects that city’s airport to a station 18.5 km away, and the S1 line of the
Beijing subway system has seven stops over a distance of 9 km. Japan is building a
long distance high-speed maglev system, the Chuo Shinkansen, by 2027 that should
connect Nagoya to Tokyo, a distance of 286 km, with an extension to Osaka (514 km
from Tokyo) planned for 2037. The Chuo Shinkansen is planned to travel at 500 km/h.
Meanwhile, there are several maglev systems and hyperloop systems built for testing.
This chapter will take several representative systems as examples to summarize and
compare the features of different systems in the application or testing stage.

5) Benefits of Maglev
The most obvious attraction of maglev trains is that they can travel faster than
traditional rail trains. The only commercial high-speed maglev, the Shanghai Maglev,
is now the fastest train in existence. It travels over 50 mph (80 kph) faster than the
fastest high-speed wheel-rail (320-kph Hayabusa, 2013). And it is only the first. The
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lack of friction between the train and the guideway removes many limits that bound
traditional trains. Maglev will only get faster from here. There are other, more subtle
qualities that also make maglev attractive:
1. Longevity: Conventional wheels and rails undergo a great deal of stress over time.
They must be replaced and repaired periodically to remain functional. In maglev,
there is no contact between train and guideway, so there is substantially less wear-
and-tear. The lifespan of maglev parts is appropriately much longer due to this fact.
Economically, this is quite an incentive, as repair and maintenance are costly and
time-consuming activities.
2. Safety: It might seem counter-intuitive that these trains are safer, as they travel so
much faster than their wheeled counterparts. It is true nevertheless. Maglev trains
are near impossible to derail. It would take something like complete guideway
collapse to part a train from its track. Additionally, weather isn’t much of a problem.
Since the trains don’t rely on friction for movement, snow, ice, and rain cause little
to no effect. Finally, it is easy to elevate the guideways. If the trains are running on
tracks ten feet above the ground, there is a smaller chance of collision with an object
on its path.
3. Energy Efficiency: Another benefit of levitation is that these trains don’t lose any
energy to friction. This gives them an advantage in efficiency. Energy consumption
is essential to the success of a transportation system. Much of the cost of operating
one goes to paying for power. Therefore, this edge in efficiency is very important.
However, while maglev trains are more efficient, they are currently not
substantially more efficient than modern high-speed rail. They do, though, have the
potential to be far superior in this category.
4. Environmental Impact: Maglev trains can make tighter turns than high-speed rails
can. This allows guideways to be built which can navigate terrain much better. The
paths can be engineered to have as little effect on the environment as possible.

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 Guideways also take up less area than rails do. This further reduces environmental
impact. And, as noted before, guideways are easily elevated off the ground. Plants
and animals alike are safer with the train traveling above them, and not barreling
by right next to them.
5. Noise Pollution: When considering a transportation project, noise (within
reasonable bounds) isn’t as large a concern as economy or safety. However, noise
reduction is still considered a positive feature. Maglev trains are quieter than
contemporary trains, so this is another point in their favor.

6) Drawbacks of Maglev
Although there are many upsides, there are still reasons why maglev trains are
not being built everywhere. Perhaps the biggest reason is that maglev guideways are
not compatible with existing rail infrastructure. Any organization attempting to
implement a maglev system must start from scratch and build a completely new set of
tracks. This involves a very high initial investment. Even though guideways cost less
than rails over time, it is hard to justify spending so much upfront. Another problem is
that maglev trains travel fast, but they might not travel quite fast enough. Countries
with high-speed rails already in place don’t want to spend billions of dollars
implementing a system that is only marginally better than the existing solution. The
market for these trains just isn’t very large at the moment. It is hard to dispute that these
trains are superior to standard ones. Regardless, more work needs to be done before it
is worth implementing them worldwide.

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7) Electrical Engineering in Maglev
Ever since the steam engine, trains have traditionally been in the domain of
mechanical engineers. They were all motors and axles, wheels and engines. However,
the introduction of maglev technology has broken that tradition. Developing these
trains has required input from a number of different fields other than mechanical
engineering, including physics and chemistry. Most importantly, though, it has brought
electrical engineers to the table. From the beginning, electrical engineers have been
major contributors to developing maglev technology. Eric Laithwaite, an electrical
engineer, developed the first linear induction motor, an important and necessary
precursor to maglev trains. Hermann Kemper, who many believe to be the father of
maglev, was also an electrical engineer. German and Japanese electrical engineers
worked to establish the maglev programs in their respective nations. And today,
electrical engineers are making the technology better and better so that it may appeal
to countries all over the world. Maglev trains have surprisingly few moving parts. They
are all about electric currents, magnets, and wire loops. Some important topics to the
field are electromagnetic fields and waves, circuit theory, feedback control systems,
and power engineering. All these falls under the expertise of electrical engineers.
Therefore, it is electrical engineers that are needed to solve the biggest problems this
technology faces. The trains need to be made faster and more energy efficient. All the
while they need to be kept well within boundaries of safety. The guideways need to be
made cheaper, easier to implement, and perhaps more compatible with existing rails.
The control systems need to be made flawless. All of these issues and more are calling
out for an electrical engineer to come unravel their answers.

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8) The Future of Maglev
Maglev technology holds great promise for the future. It has the potential to be
a cheaper, faster, safer, and greener form of transportation than we have today. And
with the help of some electrical engineers, it will become all of these things. There are
possible applications for this technology in anything from intercity public
transportation to cross-country trips. There are even proposals to build long
underground tubes, suck the air out of the tubes, and place maglev trains inside of them.
In this setting there would be virtually no wind resistance, so a train could easily reach
speeds exceeding the speed of sound (Thornton, 2007). While it may be a long time
before this technology becomes prevalent, it is difficult to deny that it will at some point
be prevalent. The advantages are too hard to ignore. As of now there is only one
commercial maglev train in use, and it has already eclipsed everything that has come
before it. How will this technology evolve and improve as we move into the future?
Only time will tell. But it is highly plausible that we now stand at the precipice of a
transportation revolution.

9) References
1) https://ieeexplore.ieee.org/document/1644911
2) https://sites.tufts.edu/eeseniordesignhandbook/2015/maglev-magnetic-
levitating-trains/
3) https://www.britannica.com/technology/high-speed-rail
4) https://physics.anu.edu.au/engage/outreach/_files/MAGLEV.pdf
5) https://www.maglev.net/transrapid-design-history
6) https://en.wikipedia.org/wiki/Electrodynamic_suspension
7) https://en.wikipedia.org/wiki/Maglev

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