• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.678-684
• /
• 2011

In 2013, Korea will become the world's second country to operate the urban Maglev system with the inauguration of demonstration line at Incheon International Airport. A prototype Maglev is under the test at KIMM's(Korea Institute of Machinery & Materials, Daejeon) track. This Maglev is an EMS(Electromagnetic suspension)-type vehicle of controlled $8{\pm}3mm$ air gap. The air gap between electromagnet and the guiderail in an EMS-type Maglev must be maintained within an allowable deviation by controlling the magnet. The air gap response is strongly dependent on the structural characteristics of the elevated guideway. For this reason, the interaction between the vehicle with electromagnets and the elevated guideway must be understood to ensure safe running. The purpose of this paper is to compare vibration characteristics of the vehicle on the switching system and other sections when the full weight condition of urban maglev vehicle that 26.5 tons per car(empty car weight 19 tons + passenger condition 7.5 tons), is applied. Through such results, Maglev vehicles and switching system can be established and the levitation stability can be improved.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2008.04a
• /
• pp.637-640
• /
• 2008

Noise generated from maglev vehicles mainly consists of two components, one is due to mechanical noise and the other due to aerodynamic noise. The former is due to the vehicle-guideway interactions and the latter results from the unsteady air flow around the vehicle. Aerodynamic noise could become more predominant around 225 km/h for maglev vehicles. In this paper, the aerodynamic noise of maglev vehicles is investigated experimentally. The results of the wind tunnel experiments of maglev vehicle models are introduced and compared. The comparison shows that the position of the main noise is between the bottom of the vehicle model and the rail. It is also found that the emitted sound pressure level is related to the gap size between the vehicle bottom and the rail.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2010.11a
• /
• pp.923-924
• /
• 2010

• International Journal of Railway
• /
• v.8 no.1
• /
• pp.15-20
• /
• 2015

As a result of the current population concentrations in urban centers, demand for intercity transportation is increasing rapidly. Railway transportation is becoming popular as an intercity transportation because of its timely service, travel speeds and transport efficiency. Among the many railway systems, the innovative and environmentally friendly maglev system has been rated very highly as the next-generation intercity railway system. Linear induction motors are widely used for the propulsion of maglev trains because of their light weight and low construction costs. The urban maglev that was recently completed in Incheon airport site employs a 110km/h class linear induction motor. However, this system was designed to meet requirements for inner-city operations and is not suitable as an intercity transportation system, which requires medium to high speeds. Therefore, this study deals with the characteristics and designs of linear induction motors used for the propulsion of maglev trains that can be used as intercity trains. Rail car specifications for high-speed trains have been presented, and the characteristics of linear induction motors that can be used for the propulsion of these trains have been derived using the finite element method (FEM).

• Journal of the Korean Society for Precision Engineering
• /
• v.28 no.11
• /
• pp.1297-1308
• /
• 2011

The light-weight design of UTM (Urban Transit Maglev)-02 car-body frames are performed, based on initial configuration. The thicknesses of fourteen sub-structures are defined as design variables and the loading condition is considered according to weight of sub-structures, electronic and pneumatic modules and passengers. For efficient and robust process of design optimization, objective function and constraints are approximated by response surface approximation. Structural analysis is performed at some sampling points to construct the approximated objective function and constraints composed of design variables. Design space is changed to find many optimal candidates and best optimal design can be found eventually. The Matlab Optimization Toolbox is used to find optimal value and sensitivity analysis about each design variable is also performed.

• Proceedings of the KSR Conference
• /
• 2011.05a
• /
• pp.93-97
• /
• 2011

This paper presents the performance and test results of propulsion system which is met the requirements of urban MAGLEV. The design of propulsion system should be considered the effect of attractive force by the magnetic levitation and train running resistance. In this paper, the tractive and braking thrust are calculated and the train performance is simulated for the service track. Finally the test results of complete car are shown to verify the performance.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.33 no.6
• /
• pp.367-374
• /
• 2020

A standard for the vibration magnitude of a maglev train is presented herein to ensure a comfortable ride for the passengers. The vibration magnitude is determined from the vertical acceleration of the car body. A parameter analysis of the maglev train system is then performed considering the vehicle-structure interaction, and a deflection limit of L/1300 is proposed to satisfy the standard for the vertical acceleration. The proposed deflection limit is applied to the dynamic analysis of the actual maglev train system to assess applicability. Compared with the existing standard for the guideway structure, the proposed deflection limit is expected to enable economical design and construction.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2014.10a
• /
• pp.622-624
• /
• 2014

A maglev train records a host of physical variables such as gaps, voltages and currents for suspension control and monitoring purposes. These data available from a maglev contains wealth of information that can be explored for various uses. One possible of such application is to use the gap data to estimate the shape of the rail, especially at the joints where rails are connected. The eddy current sensors that measure the gap between the rail and the car body produce large peaks around the joints. The suspension controller discards these peaks. Since the shape of the peaks is related to the joint, however, these peaks can be utilized to estimate the shape of the joints. In this paper, we present preliminary results on estimating the joint shape using the peak data. The results show that the approach is promising, albeit several technical difficulties to overcome.

• Journal of the Korean Society for Precision Engineering
• /
• v.34 no.1
• /
• pp.41-46
• /
• 2017

Magnetically levitated (Maglev) vehicles maintain a constant air gap between guideway and car bogie, and thereby achieves non-contact riding. Since the straightness and the flatness of the guideway directly affect the stability of levitation as well as the ride comfort, it is necessary to monitor the status of the guideway and to alert the train operators to any abnormal conditions. In order to develop a signal processing algorithm that extracts guideway irregularities from sensor data, virtual testing using a simulation model would be convenient for analyzing the exact effects of any input as long as the model describes the actual system accurately. Simulation model can also be used as an estimation model. In this paper, we develop a state-space dynamic model of a maglev vehicle system, running on the guideway that contains jumps. This model contains not only the dynamics of the vehicle, but also the descriptions of the power amplifier, the anti-aliasing filter and the sampling delay. A test rig is built for the validation of the model. The test rig consists of a small-scale maglev vehicle, tracks with artificial jumps, and various sensors measuring displacements, accelerations, and coil currents. The experimental data matches well with those from the simulation model, indicating the validity of the model.

• Journal of the Korean Magnetics Society
• /
• v.4 no.2
• /
• pp.106-113
• /
• 1994

This paper deals with the magnetic forces of the combined levitation and guidance EDS(Electrodynamic Suspension) maglev system when the car bogie is tilted by the roll, pitch and yaw. The end effect on the magnetic forces are considered by calculating the air-gap flux without the assumptions for its pattern. Induced voltages and currents of the ground coils are given as results. The restoring torque due to roll, pitch and yaw of the bogie body are also examined. It has been shown that the end effect of the concentrically loaded vehicle are not negligible and the combined EDS is stable maglev system against disturbing forces.