• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.61-63
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• 2002

At recently, it is regarded efficiency of the electric motor. and the development of the electric motor of new concept and research according to the development of new material and a elevation of magnetic property of magnetism material have been processed actively. One of the that, the transverse flux linear electric motor is studing actively about application method in many ways. because it has high power density and efficiency more than a induction motor. In this study we introduce apply field of the electromotor which follows Picture and find out the characteristic using the 3D Finite Element Method(FEM).

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.413-415
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• 2001

A railroad vehicle(Light weight electric rail car, Urban railroad, High-speed railroad) need to construct propulsion- system capacity experiment equipment to test performance or to estimate confidence. Experiment equipment in interior have been used Flywheel which is equal to the same inertia as railroad straight moment. But mechanical inertia using flywheel don't change inertia and can't embody traveling-struggle which is similar to actual traveling-struggle. We propose the method to embody electric railroad load system with inertia using electric servo motor in order to get the characteristic of real vehicle load, and confirm this algorithm with simulation and experiment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2358-2360
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• 1999

This study describes the reliability assessment of 3 years-aged polymer insulators using polymer characterization techniques such as SEM, contact angle, DSC, FTIR. Two kinds of polymer insulators were dismounted from 5 fields. All polymer insulators showed the micro-cracks and the reduction of characteristic peaks on the shed surface. Contact angle was increased with time. Although some superficial changes have occurred, there are no significant changes in various properties. Comparison of dismounted insulators to new ones revealed that the field-aged insulators are reliable for the present.

• Journal of Magnetics
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• 제18권4호
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• pp.466-472
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• 2013

This paper presents a new design of the hybrid magnet engine valve actuator using the shorted turn for enhanced dynamic performance. The quick response of coil electric current is the most important factor that determines the opening and closing performance of the hybrid magnet engine valve. The conventional hybrid magnet engine valve actuator, however, has a delayed initial electric current rising when it is driven by voltage control because of the coil inductance which is a typical characteristic of an electromagnetic coil. A shorted turn is newly placed into the upper yoke of the hybrid magnet engine valve actuator to reduce coil inductance and thus, to hasten the initial electric current rising. We performed a dynamic finite element analysis to demonstrate the improvement of the dynamic characteristics of the hybrid magnet engine valve actuator due to the shorted turn.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1978-1983
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• 2008

With the increase in population, the area of human activities has expanded, resulting in the dramatic increase in the need for transportation system. Various infrastructures necessary for efficient logistics, however, have not been supplied enough and the logistics efficiency in Korea is in a bad situation now. As a result of the situation, the demand for the railroad transportation system that can provide large volume transportation has increased dramatically. An electric railway system is composed of high-tech subsystems, among which main electric equipment such as motors and converter are critical components determining the performance of electric vehicle. Among the on-board equipments, traction equipment is important part that has influence on safety and performances of vehicles. We is studied for high-speed train of foreign countries. From this research, we knows that axle weight of HEMU-400x is reasonable within 13ton.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 A
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• pp.97-99
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• 1997

For two decades and more, a lot of research work on the biological effects of EMF (Electromagnetic Field) on human health have been reported. Electric facilities in a typical substation are the main source of magnetic field. This paper presents the measurement and analysis of magnetic field in 345/154KV outdoor substation. The magnetic field depends on the currents which distributed by electric facilities. The result of this paper will be able to be used as basic informations to reduce the level of EMF from the electric utility facilities.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제49권7호
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• pp.468-474
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• 2000

This paper presents an investigation of the parameter modeling on the basis of Finite Element (FE) analysis in which the variable frequency characteristic in field weakening is considered in Interior Permanent Magnet Synchronous Motors (IPMSM). The parameters of IPMSM have nonlinear characteristics not only in accordance with the load variation but also with the current phase angle of a system fed inverter. From the results of FE analysis, the performances of torque and speed-power are simulated and the validity of the proposed FE analysis is compared with experimental results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.215-217
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• 2005

In this paper, the inductive power collector using electromagnetic induction for the PRT{Personal Rapid Transit) system is suggested and some ideas for power collector design to improve the power transfer performance are presented. The proposed the inductive power collector is used for the PRT system, which has a large air-gap and demands a large electrical power capability. But, low output power is generated due to a loosely coupled characteristic of the large air-gap. Therefore, double layer construction of secondary winding, which was divided in half to increase both output current and output voltage was suggested. Also, model of power collector and parallel winding structure are presented, in addition, the performance of inductive power collector to alignment condition between the primary power line and the inductive power transformer was verified by computer simulation of 2kW model.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 전문대학교육위원
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• pp.184-190
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• 2005

The railway characteristic, which is concerned, as most utilities is unbalance produced by the large single-phase loads. Here are two theoretical concerns associated with unbalanced loads. First, generator rotor heating resulting from unbalanced current flow, Second, there is the possibility of motor overheating in industrial plants, due to the unbalanced voltage. Therefore, the exact assessment of the voltage unbalance must be carried out preferentially as well as load forecast at stages of designing and planning for the electric railway system. This paper proposes a new analysis model to more effectively estimate voltage unbalance. Numerous distributed circuits in the electric railway system are composed by components. The entire system can be easily modeled by the combination of four-port representation of each component in parallel and/or series. Simulation results using the model are compared with field data, and it verifies the accuracy of the proposed model.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 B
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• pp.850-852
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• 1996

High impedance fault (HIF) is defined as fault that general overcurrent relay can't detect or interrupt, Especially when HIF occur under 15 kV, energized high voltage conductor results in fire hazard, equipment damage or personal threat. Because most HIF occur arc, HIF detection using arc is to increase. Numerical arc model can be applied in an electromagnetic transients program (EMTP) to reproduce the dynamic and random characteristic of arcs for any insulator arrangement, current and system voltage. It allows the representation of any network configuration to be investigated, so the digital simulation of arc faults through air can be substitute for demanding power arc test.