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In this paper, a new passive Maglev system is presented that is capable to levitate at a short distance from a dedicated guide. The magnetic suspension is assured by the repulsion of proper shaped permanent magnets that are present both on the fixed guide and on the moving suspended part. The presence of a conductive (aluminum) sheet that surrounds the magnets on the guide allows to overcome the intrinsic instability of the system when the suspended part is in relative motion with respect to the guide. The motional induced electric currents on the sheet interact with the magnets of the mover producing a stabilizing force. The detailed structure of the proposed system is described and the main results of the simulations by means of a hybrid electromagnetic FEM-MOM code coupled with the equation of motion of the rigid body are shown and commented. Index Terms--Finite element method (FEM), force computation, magnetic levitation, method of moments (MOM), moving conductors.

We describe the driving mechanism of a maglev planar transportation vehicle (MPTV). The levitation mechanism consists of four magnetic wheels and four rotary machines. The combination of the linear induction motor mechanisms enables the vehicle to travel with planar motion. The wheels provide stability without disturbing the planar motion. Because all the mechanisms use electrodynamic forces, the working range of the MPTV can be expanded simply by paving the workspace with a conductor. The feasibility of the MPTV has been verified in several experiments. Index Terms--Linear induction motor, magnetic levitation, magnetic wheel, planar motion.

The development of different Maglev systems, their application for passenger transportation and the promotion of the Maglev transportation in China are described. The studies have shown that the Maglev has many advantages for fast passenger transportation and they are already matured for practical application due to continuous development.

A magnetic-levitation (maglev) transportation system including levitation and propulsion control is a subject of considerable scientific interest because of highly nonlinear and unstable behaviors. In this paper, the dynamic model of a maglev transportation system including levitated electromagnets and a propulsive linear induction motor (LIM) based on the concepts of mechanical geometry and motion dynamics is developed first. Then, a model-based sliding-mode control (SMC) strategy is introduced. In order to alleviate chattering phenomena caused by the inappropriate selection of uncertainty bound, a simple bound estimation algorithm is embedded in the SMC strategy to form an adaptive sliding-mode control (ASMC) scheme. However, this estimation algorithm is always a positive value so that tracking errors introduced by any uncertainty will cause the estimated bound increase even to infinity with time. Therefore, it further designs an adaptive fuzzy-neural-network control (AFNNC) scheme by imitating the SMC strategy for the maglev transportation system. In the model-free AFNNC, online learning algorithms are designed to cope with the problem of chattering phenomena caused by the sign action in SMC design, and to ensure the stability of the controlled system without the requirement of auxiliary compensated controllers despite the existence of uncertainties. The outputs of the AFNNC scheme can be directly supplied to the electromagnets and LIM without complicated control transformations for relaxing strict constrains in conventional model-based control methodologies. The effectiveness of the proposed control schemes for the maglev transportation system is verified by numerical simulations, and the superiority of the AFNNC scheme is indicated in comparison with the SMC and ASMC strategies. Index Terms--Fuzzy neural network (FNN), linear induction motor (LIM), maglev transportation system, magnetic levitation (maglev), sliding-mode control (SMC).

The article discusses the design and testing of a persistent current high temperature superconducting (HTS) magnet compatible with the low temperature superconducting (LTS) magnet for Yamanashi Maglev Test Line (YMTL). Findings reveal the achievement of a maximum speed of 553.9 km/h.

Two levitational configurations for the superconducting launch ring concept are examined. Results suggest that both the attractive and shear-force configurations are capable of complete static stability over the complete velocity range from 0 to 10 km/s.

The article examines the design and testing of the high temperature superconducting (HTS) magnet for the superconducting Maglev. Findings reveal that the HTS magnet is operational in a persistent current mode at a rated magneto-motive force of 750 kA with a top speed of 553 km/h.

The article discusses the design and testing of a high temperature superconducting (HTS) levitation tester based on electrodynamics suspension (EDS) Maglev. Findings reveal the saturation of the levitation force when the speed of Maglev was faster than 60 km/h.

The article discusses the design and performance analysis of a linear permanent magnet synchronous motor for driving a small scale prototype Maglev vehicle. Results suggest that the linear driving system is capable of generating an appropriate driving force for the high temperature superconductor (HTS) Maglev vehicle prototype.

This article discuses the concept of intermodal transportation and an innovative magnetically levitated (maglev) technology used in the alternative mode of travelling. The autoshuttle system transports automobiles with their passengers in ventilated transport cabins, which enter and leave a convoy running at a constant speed.

A study of superconducting magnets utilized for magnetically levitated (Maglev) transportation systems is presented. The results indicate the importance of accurate vibration analysis in the development of superconducting magnets that will help minimize mechanical loss for Maglev train operations. The development of an on-board refrigeration system for superconducting magnets that does not require supplies of either liquid nitrogen or liquid helium is ongoing.

Research was conducted to examine the schemes relating to the use of high temperature YBaCuO superconducting bulk materials for magnetic levitation (Maglev) vehicle. The first scheme involved YBaCuO bulk superconductors arranged above the rail using NdFeB permanent magnets. The second involved the electromagnetic suspension Maglev vehicle using high temperature superconducting permanent magnets or high temperature superconducting wire. The third was the electromagnetic suspension Maglev vehicle using high temperature superconducting permanent magnets.

The National Maglev (magnetic levitation) Initiative (NMI) of America has developed a maglev program which will enable quick, comfortable and smoother transportation due to higher acceleration rate, which is attributed to low friction and the light weight composite structure. The vehicles operate due to the action of magnetic waves from a linear synchronous motor on the vehicle's pathway. In Germany, a Transrapid 07 maglev, and in Japan, maglevs operating on electrodynamic suspensions, have been developed.

In EMS-MAGLEV high-speed transport systems, devices for propulsion, levitation and contactless on-board electric power transfer are combined in a single electromagnetic structure. The strong coupling among the windings affects the performance of each device and requires the utilization of numerical codes. The paper describes an overall optimization procedure, based on a suitable mathematical model of the system, which takes into account several items of the system performance. The parameters of the model are calculated by an automated sequence of FEM analyses of the configuration. Both the linear generator output characteristics and the propulsion force ripple are improved applying the procedure to a reference configuration. The results are compared with the results obtained by a sequence of partial optimizations operating separately on two different subsets of the geometric parameters. Index Terms - Electromagnetic optimization, High-speed transport systems, Linear synchronous motor, Magnetic levitation of electromagnetic type.

A Maglev system using permanent and electromagnet is described. Such a system offers the advantages of high lift force to magnet weight ratio and nearly zero ohmic loss of its control winding. However, it is more difficult to control. Also, unlike the conventional electromagnetic levitation system, the control current is always maintained at zero value even with load variations. Analysis shows that the size and weight of this system are smaller by a factor of three compared to the conventional Maglev system. Basic design criteria and control strategy using variable structure control method are given, together with experimental results of a small model to verify its feasibility and good dynamic response.

Linear induction and synchronous motors have been the favored approaches for achieving linear propulsion in the Maglev community. One alternative is PLIM, a less conventional Pulsed Linear Induction Motor. Among the advantages realized through PLIM are elimination of low power factor power transfer, smaller end winding overhang, and simpler electronics. Examined in this document are various embodiments of this approach with discrete rectangular guideway coils, and the tradeoffs to using full wave and half wave excitation pulses. Index Terms--Induction, Maglev, pulsed, resonance.

Because of the many special characteristics of bulk superconductors, they could be used as a flux source instead of electromagnets or permanent magnets in maglev systems. In this paper, we discuss the application of bulk superconductors to the EMS-type maglev vehicle. The configuration of the magnets consists of separated bulk superconductors and electromagnets. An attractive force between the superconducting bulk magnet and an iron rail is generated by the magnetic flux pinned in the bulk superconductors. The electromagnets are controlled to stabilize the required levitation force. Numerical analysis shows that the attractive force in this configuration is large enough to support the weight of the vehicles and that the influence of magnetic hysteresis of the superconductors on the electromagnetic force characteristics is small. Index Terms--Bean model, bulk superconductor, EMS-type maglev vehicle, magnetization.

Electrodynamic systems (EDS's) for maglev have an advantage over electromagnetic systems (EMS's) in that the stability is built into the system. EDS's induce the currents used for levitation and guidance, while EMS's impose those currents with controlled feedback. The movement of a magnet over properly designed EDS coils results in forces to keep the system fixed in the lowest energy or null flux spot. In the past such systems have been examined through two-dimensional boundary element techniques [1], [2]. An approximation to the full three-dimensional time harmonic problem is obtained through Laplace transform theory after using boundary element methods to predict the mutual coupling of the magnets with the track coils. The analytic solution offers helpful design and operation guidelines.

The UK railway industry is recovering from its planned privatization while other countries advance with the development of faster trains using new engineering technology. The French TGV under development will run at speeds between 350-400 km/hr. The German Transrapid using synchronous long-stator linear motor will have a speed of 510 km/hr. Japan is developing the High Speed Surface Transport system and a Linear Motor Car which will run at speeds above 500 km/hr. Development of CyberTran vehicles using large number of small vehicles for US cities is discussed.