• Proceedings of the KSME Conference
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• 2008.11a
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• pp.609-611
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• 2008

Eddy current is usually generated in material with high conductivity by time-varying source such as AC current and also is induced in the moving source with relative velocity. The contactless magnetic brakes make use of the braking force from the eddy current generated by moving source and currently used for the secondary brakes of heavy trucks, buses and rail vehicles. This study aims to design the magnetization pattern of a permanent magnet type eddy current brake system to maximize the braking force. The analysis of the brake system is based on the two-dimensional finite element analysis. We use the sequential linear programming as the optimizer and the adjoint variable method for the sensitivity analysis.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.9 no.3
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• pp.231-236
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• 2015

In this study, we propose a non-contact circular eddy current load brake using permanent magnet that can be applied to the rehabilitation exercise equipment. The circular eddy current load brake is manufactured and is evaluated for performance. This has the torque value of 49% compared to a "ㄷ" type eddy current load brake having a fixed load. And we confirmed that load is regulated due to the conductivity and air gap. Proposed load brake is adjustable according to the user's condition and can be applied to the equipment having advantages such as miniaturization and cost reduction.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.110-115
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• 2002

In this paper, the results of an analysis of the dynamic behavior of the eddy current brake(ECB) system are presented. The measured irregularity of the track in Korean high speed line and the track irregularity given by ERRI(high level) were used for simulation. The wheel-rail profile combination were analyzed with different rail gauges. A model of the bogie with an substitute body for the carbody was implemented in the Multi-body-Simulation Program SIMPACK. The ECB frame was modelled both as flexible body and as rigid body. Four different driving conditions were analyzed. In this study dynamic behavior in general were performed to evaluate the design of eddy current brake system and specially the effect of damper was also studied. A comparison of simulations with and without damper shows that the damper have most effect for lower speed. The simulation results will be verified by comparison with measured data from on line test and also used for improving design.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.345-350
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• 2001

Dynamic behavior of high speed train is very important because the high speed train should be safe and satisfied with the ride comfort. An eddy current brake system is mounted on trailer bogie and wheelset. The eddy current braking force longitudinally exerts on the articulated trailer bogie and the attraction force vertically exerts on the wheelset. Because a frame of eddy current brake system is flexible, these forces generate the vertical vibration at middle point of the frame. Also, the vibration change the vertical clearance between an electromagnet and top of rail which affect the magnitude of braking and attracting forces. Therefore, the dynamic behavior of the eddy current braking system must be predicted for design the dynamic characteristic of its mounting system when normally operate on rail which have irregularity. Vampire program is used for prediction of the dynamic behavior of an eddy current braking system. Five design variables and five performance index are considered for optimization through D-optimal experimental design in this paper. Also model center is used to search the optimal point for sum of performance index with variational matric method.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.889-891
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• 2001

The eddy current brake system is one of important application of eddy current. It is adequate to obtain safe braking force in high speed transportation system and electric vehicle etc. There is a variety of configurations and materials used in manufacturing of eddy current brakes. This paper proposes the eddy current brakes which uses permanent magnet. The dynamic characteristic has been analyzed to FEM and compared with measured data.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.9
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• pp.1492-1498
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• 2003

This study proposes a new conceptual Hybrid Electric Brake System (HEBS) which overcomes problems of a conventional hydraulic brake system. HEBS adopt a contactless type bake system when a vehicle speed is high, to obtain superior braking performances by eddy current. On the contrary, when a vehicle speed is low, HEBS employs a contact type brake system such as conventional hydraulic brake system to generate higher brake force. Therefore, HEBS transfers faster the braking intention of drivers and guarantees the safety of drivers. Braking torque analysis is performed by using a mathematical model which is proposed to investigate the characteristic of a vehicle dynamics when the brake torque is applied. Optimal torque control is achieved by maintaining a desired slip corresponding to the road condition. The results show that HEBS reduces the stopping distance, saves the electric energy, and increases the stability.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.318.1-318
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• 2002

In this paper, the results of an analysis of the dynamic behavior of the eddy current brake(ECB) system are presented. The measured irregularity of the track in Korean high speed line and the track irregularity given by ERRI(high level) were used for simulation. The wheel-rail profile combination were analyzed with different rail gauges. A model of the bogie with an substitute body fur the carbody was implemented in the Multi-Body-Simulation Program Simpack. (omitted)

• Proceedings of the KSR Conference
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• 2001.10a
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• pp.267-272
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• 2001

A FEM-based analytical approach was used to evaluate the static strength and the fatigue strength of a KHST bogie including eddy current brake system. Calculation was carried out in the fields of linearity and small deformation. The yield strengths were used as criteria for evaluating the static strength and the fatigue limits were used as criteria for evaluating the fatigue strength. The analysis results show that there is not any location that exceeds the allowable criteria.

• Proceedings of the KIEE Conference
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• 2003.04a
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• pp.125-127
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• 2003

Brake forces due to eddy-currents induced by the relative motion of a conductor and a magnetic devices: motors, brakes and magnetically levitated vehicles. In particular, the practicality of using permanent magnet in eddy-current brakes system is obviously recent, due to the manifold improvement in magnet materials and technology. For such a system we give analytical formulas considering eddy-current distribution as variables: flux density for each region and forces.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.48 no.11
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• pp.611-616
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• 1999

The introduction of the eddy current braking(ECB) system in HSRT(high speed railway train) is known to be advantageous, in that the system is independent on wheel-rail adhesion coefficient which is greatly affected by weather condition. It also minimize the maintenance of the brake system and does not require any additional electric energy because it is powered form the regenerated power at the time of the braking. In this study, the braking and attraction forces of the ECB are simulated by 2-D FEM and are experimentally verified on a down-scaled prototype. A control algorithm of the ECB is proposed to generate constant braking torque using linear variation of the reference current according to speed. Experimental results shows that the constant torque is generated over all operating speed region by developed control algorithm.