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The EMS (Electro-Magnetic Suspension) maglev train uses attractive magnetic forces to neutralize its weight, which puts a rather high requirement on the smoothness of the track since the levitation gap is generally 8∼10 mm. It has been observed that in a traveling urban maglev train, the levitation gap error of the rear levitation unit in a levitation module is generally more prominent than that of the front levitation units; and under poor track conditions, the rear electromagnet of the levitation unit is more likely to clash with the track and to cause a levitation failure. However, this phenomenon has not yet been well interpreted. In this paper, a model of the levitation module in a maglev train is built to study the responses of the levitation gaps under different vehicle speed and track conditions, and results show that the levitation module is sensitive to some specified wavelengths of the track irregularities, and the analysis well interprets the reason that causes the difference of the response for the front and the rear levitation unit under track irregularities. A control strategy is also proposed to reduce the rear gap fluctuation.

Magnetic levitation, maglev, or magnetic suspension is a method by which an object is suspended with no support other than magnetic fields. This project describes the design procedure, analysis, and control of a single actuator magnetic levitation system. First the details of the system design and construction are presented, followed by an analysis of the relevant sub-systems and controller theory. Experimental levitation data is collected and compared to the theory. Utilizing a phase lead-lag controller, the goal is to investigate magnetic levitation and to design a working system capable of levitating an object without any form of support, maglev system is made stable for the levitation of a steel ball. Despite the simplicity and low cost of the position sensing system, it is able to detect the ball position. The successful operation of this system made of relatively low cost, low precision components reveals that compact, cheap, integrated magnetic levitation systems are becoming more feasible for a variety of applications with the increasing availability of new materials and faster, cheaper computer processing power.

By translationally moving a magnetic source above a conductive plate guideway both levitation and drag forces are created. Unfortunately, the electrodynamic drag force can be quite high [1]. Kratz studied a double Halbach array topology, such as shown in Fig 1 [1], and used a simple curve fitting approximation to model the forces. Kratz experimentally showed that a significant reduction in drag force can be created when using this “null current” approach. Much earlier Urankar derived analytic equations for a similar double coil system [2].

In this paper, a novel cylindrical magnetic levitation gravity compensator is proposed, of which the mover is composed of several permanent magnet rings in the arrangement of Halbach structure and the stator is composed of one permanent magnet ring and four copper coils. The new vacuum compatible gravity compensator can be applied to the 6-DOF high precision magnetic levitation stage as the vibration isolation and leveling device. Firstly, the analytical model of the magnetic levitation gravity compensator is established. The flux density distribution of the Halbach magnet array rings is obtained by using equivalent current model. Then the expressions of magnetic levitation forces and vertical stiffness are derived. Secondly, finite element method (FEM) is used to calculate the magnetic levitation forces in order to verify the analytical model. The results from FEM are in good agreement with the ones from analytical model, which indicates that the analytical model is accurate and reasonable. In addition, a cooling system for the magnetic levitation gravity compensator is designed and the thermal field of stator part is calculated. Last, the temperature rise experiment is achieved.

This paper aims at Design, Fabrication and Control of a single actuator magnetic levitation system. A physical design model of Magnetic Levitation System have been presented at the initial phase. Modeling and Simulation of this non-linear magnetic levitation system is proposed with feedback linearization where a non linear state space transformation is used to linearize the system exactly. After this, experimental setup and construction of actual magnetic levitation system is presented. Experimental Levitation data is collected and compared to the theory. Magnetic levitation system considered in this study is taken as a neodymium magnet suspended in a voltage controlled magnetic field. Dynamic behavior of the system was modeled by the study of electromagnetic and mechanical subsystems. State space model was derived from the system equations. For high accuracy in position detection, Hall effect sensor SS49E was utilized. The successful operation of this system was obtained using relatively cheaper and simpler magnetic levitation subsystems and components.

This paper deals with the design of levitation electromagnet for super high speed magnetic levitation (Maglev) vehicle. Electromagnetic characteristics of levitation magnet are analyzed by finite element analysis. Levitation force ripples and cogging force are reduced by adopting core separation. 4-pole cutoff model has been manufactured to verify the design. A static force experiment is carried out with test model.

This paper describes the levitation and guidance control of a passive magnetic levitation tray system. In this system, a moving tray is completely contactless and has no electric equipments. Lifting, guiding and propelling forces are generated by external electromagnets. Especially, we focused on the levitation and guidance control in this paper. We designed the controllers and evaluated their performances through experiments.

This paper deals with the design and characteristic analysis of small scale magnetic levitation and propulsion system for maglev train application. A magnetic circuit model and its results were derived for the levitation and propulsion magnets. Also, we verified it by comparing the experiments with simulation.

This paper deals with the zero-power control of magnetic levitation (maglev) vehicles that use permanent magnets as well as electromagnets for levitation. The nominal load is levitated by permanent magnet and the current consumption for stable levitation can be reduced. In order to guarantee the tracking capability, the proposed controller is based on the state feedback controller and modified to balance attraction force and total weight. The commanded voltage is used instead of the coil current in the feedback loop so that the current measurement can be avoided. A full-scale hybrid maglev tester was constructed and some experiments were carried out to show the performance of the proposed method.

This paper proposes a magnetic levitation system without other assistant devices that can move in wide area (< 300times300 mm2) as well as in high precision (< plusmn100 nm).

Stability and controllability are the core topics for any maglev system. An active magnetic array is introduced and used in the novel maglev configuration. The proposed passive EDS system uses Halbach arrays for self-regulation and levitation with active magnet arrays for stability and ride comfort control. The system is self-regulated in the lateral, roll, pitch, and yaw directions. The system configuration, stiffness, and levitation dynamic are investigated.

The rotation of permanent magnets above a conducting nonmagnetic surface such as aluminum creates a traveling time varying magnetic field that can inductively produce levitation and propulsion forces simultaneously. These forces could be used to create a relatively cheap form of Maglev transportation as the track does not need to be electrified and both the levitation and propulsion are created by the one mechanism. Although large amounts of current are necessarily induced in the track, simulations have shown that this method of Maglev appears to use less energy than electrodynamic Maglev systems while at the same time creating large propulsion forces. The use of Halbach magnets enables a sufficient levitation to weight ratio to be attained.