Jia-Su Wang and Su-Yu Wang
3 Magnetic levitation
Levitation and suspension have been for centuries associated with psychic and stran-
ge phenomena in which an object occupies a fixed position in a gravitational field
without any direct physical contact. The interaction between objects in this suspended
state will not bring friction, energy loss, and heat generation at the interface. Magnetic
levitation refers to the suspension phenomenon associated with a magnetic field. The
characteristic is a suspension phenomenon without direct contact between the object
and the magnetic sources. Magnetic levitation is abbreviated as Maglev. Maglev is a
general term, but in some cases, it is often thought to refer to the Maglev train. This is
perhaps due to the influence of these applications in the field of traffic. In this book,
we use the following definition, as not to cause unnecessary confusion. The term
“Maglev” maintains its original meaning. It can be used as an attributive to define
other specialized magnetic levitation, for example, Maglev train, Maglev bearing, etc.
In this book, the first letter of Maglev is capitalized.3.1 Introduction
After the development of the high-speed information technology, the human race
dreams of a “door-to-door” high-speed transport system just like the modern infor-
mation technology. The conventional automobile transport system has many disad-
vantages, such as traffic accidents, energy consumption, pollution, traffic jams, etc.
Therefore, ground transportation with tracks is considered as one of the mainstream
transport methods of the 21st century. Traditional railway transport has not solved
the future problems of ground transportation at high speed. High-speed railway
(HSR) emerges as the times require. Overall, airline, road traffic, and HSR modes
compete actively with each other in the distance range of 300 to 1000 km, and the
result is that the HSR occupies obvious advantages in the market. The speed of 250–
350 km/h with HSR cannot meet the demand for higher speed or ultra-high speed.
In a 1000-km journey, people readily choose airline traffic. However, Maglev has
a higher speed and better safety, so that the Maglev technology becomes one of
the best choices for the future ultra-high-speed transportation. The Maglev system
can achieve speeds of 500 km/h or even thousands of km/h, have lower energy
consumption and life cycle costs, attract more passengers, and produce less noise
and vibration than HSR. In order to facilitate the reader’s understanding of Maglev
transportation. This chapter will first introduce a general synopsis of the traditional
railway and then discuss the levitation phenomenon, magnetic levitation concepts,
permanent magnet (PM) levitation, and the normal conductive Maglev. The supercon-
ducting Maglev, LTS and HTS Maglev, will be discussed in the next chapter. Various
https://doi.org/10.1515/9783110538434-003