• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.681-682
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• 2006

This paper deals with the preliminary study on the HTSC levitation magnet for MAGLEV operating in persistent current mode (PCM). The high temperature superconducting (HTSC) levitation magnet consists of two single-pancake type coils wound with Bi-2223 wire and a persistent current switch (PCS). The levitation magnet was designed by using 3-D finite element analysis. The suspension system for high-speed electrodynamic suspension (EDS) maglev should operated in persistent current mode. It is important to develop a technology to minimize the joint resistance of splice between two HTSC wires. The PCS was observed with respect to various magnitude of charging current. Based on these results, the levitation system using HTSC wire will be further studied.

• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.177-179
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• 1994

In conventional maglev system, the individual control system has been adopted. When this control system is applied, it is able to degrade the stability of levitation because of the interferance between magnet. And so, it is desiarable to be controled in global, collective control. In doing so, the dynamic suspension characteristics is improved. In this paper, collective control system using the equivalent inertia is examined and the dynamic characteristic are compared with that of individual control system.

• Proceedings of the KIEE Conference
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• 1997.07e
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• pp.1850-1852
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• 1997

In this paper, the behavior and effect of conducting particles in a $SF_6$ insulated electrode system, are presented. It is shown that the bouncing voltage of the particle is independent of particle length, and that the breakdown voltages are affected by the particle length. The longer the particle, the lower the breakdown voltages. The bouncing-off, the lift off and breakdown voltages increase as the particle diameter increase. The breakdown voltage of free particle is lower than fixed particle on the enclosure.

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.101-104
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• 1999

This paper presents the design of state feedback controller with state observer(dynamic filter) for Electro-Magnetic Suspension System. Also, the gain scheduling technique using state observer is analyzed in the time domain and frequency domain.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.4
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• pp.578-585
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• 2015

Electromagnetic levitation system(EMLS) is one of the well known nonlinear systems. Often, it is not easy to control an EMLS due to its high nonlinearity. In this paper, we first apply two linearization method(jacobian and input-output feedback linearization) to design two feedback controllers for an EMLS. Then, by observing the advantages of each controller, we design a switching control algorithm which engage two controllers depending on the position of the steel ball in order to achieve the improved performance over each controller. The validity of our switching control approach is verified via both simulation and actual experimental results.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.7
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• pp.1067-1074
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• 1994

This paper deals with the combined levitation and guidance EDS(Electrodynamic Suspension) Maglev system. Levitation and guidance forces generated in figured-of-eight coil are examined. End effect of Superconducting magnets is considered in that the air gap flux has been calculated using the finite number of magnets. Induced emfs and currents of ground coils are given as results. Eletromagnetic forces vary according to the built-in position of magnets. Levitation forces of the first magnet pair are the smellest and those of the second one are the largest. This result shows that the end effect of SCMs should be considered in a concentrated magnet system.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.281-283
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• 1998

The 4-poles LHSM with transverse bar track was designed on the base of the performance equations and the equivalent circuit model. However, the magnetic shape factors, such as Carter's and Green's coefficients, $B_{min}/B_{max}$ and leakage factors, were important in the design and analysis of LHSM. Consequently, these coefficients were computed from the analytical expressions and examined from FEM analysis in detail.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.152-154
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• 1998

This paper deals with propulsion system for the UTM-01(Urban Transit Maglev). We experiment about the LIM and the inverter at 4 running test maglev vehicle. It is measured voltage, current, power factor for inverter output. And we discussed about efficiency of the LIM about maglev system.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.308-311
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• 1998

Experiments and design efforts have been made to develope a hybrid-type magnet for magnetically levitated(MAGLEV) vehicle using NdFeB permanent magnet. The permanent magnet, which embedded in both poles of the magnet, has been designed, analyzed using FEM program. The model is manufactured and tested to verify its performance.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.669-671
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• 2000

This paper introduced the scheme that it improved performance of magnetic levitation system with zero power controller. Magnetic levitation is used widely, but it is complicated and difficult to control due to having nonlinear characteristics of gap and current. So, it is proposed a scheme considered changed gap according to variable load and is verified by simulation and experiments in this paper.