• Journal of the Korean Society of Safety
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• v.27 no.5
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• pp.49-54
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• 2012

There is a possibility that electrical sparks may occur at discontinuities in metallic structures from distance of close to high power radio/radar transmitters. Voltage may be induced on these metallic structures by the radio-frequency transmitter. In this case, a person who comes into contact with these structure may be undergone a severe electrical shock. In this paper, assessment of the electrical shock and ignition hazards was investigated through experimental which are consisted radio transmitter and metallic loop-type structure in shield room. We measured that the induced voltage was highest at 61 MHz of transmission frequency, and confirmed the possibility of electric shock and explosion induced by a voltage or spark. But it is needed additional research where is opened site.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.1
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• pp.19-25
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• 2000

This paper describes the sheath induced voltage in underground transmission cable system which will be operated with cable cover protection unit(CCPU). Simulation was carried out to analyze the sheath induced voltage in the real cable system which was installed by 154㎸ CV cable in the case with and without CCPU. The sheath induced voltage will be also analyzed according to the change of grounding method, fault resistance and fault angle. Simulation was performed using EMTP and ATP Draw, the simulation results show whether the CCPU in necessary or not in underground transmission power cable system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.5
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• pp.680-688
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• 2015

Hybrid type combined transmission systems is being operated by AC and DC line at the same space will be expanded instead of the overhead line. However, such hybrid type combined system has problem like the arrangement selection of DC cable for effective system operation. In this paper, to select the proper arrangement of DC cable, induced voltage of DC cable influenced by AC cable was analyzed in case of several type arrangement of DC cable. Such induced voltage is in detailed analyzed not only in case of steady, but transient state. The arrangement which has the lowest induced voltage is selected as the proper one. EMTP/ATPDraw is used for modeling and analysis of hybrid type combined transmission system.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.2
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• pp.191-196
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• 2010

The electricity distribution system in Korea is adopting a multi-grounding system. Protection of this distribution system against lightning is performed by installing overhead ground wires over the high voltage wires, and connecting the overhead ground wires to the ground every 200 m. The ground resistance in this system is limited not to exceed $50\Omega$ and overhead ground wire and neutral wire are multiple parallel lines. Although overhead ground wire and neutral wire are installed in different locations on the same pole, this circuit configuration has duplicated functions of providing a return path for unbalanced currents and protecting the distribution system against induced lightning. Therefore, the purpose of this study is to analyze the induced lightning shielding effect according to the neutral wire installation structure of a 22.9kV distribution line in order to present a new 22.9kV distribution line structure model and characteristics. This study calculated induced lightning voltage by performing numerical analysis when an overhead ground wire is present in the multi-grounding type 22.9kV distribution line structure, and calculated the induced lightning shielding effect based on this calculated induced lightning voltage. In addition, this study proposed and analyzed an improved distribution line model allowing the use of both overhead wire and neutral wire to be installed in the current distribution lines. The result of MATLAB simulation using the conditions applied by Yokoyama showed almost no difference between the induced lightning voltage developed in the current line and that developed in the proposed line. This signifies that shielding the induced lightning voltage through overhead wire makes no difference between current and proposed distribution line structures. That is, this study found that the ground resistance of the overhead wire had an effect on the induced lightning voltage, and that the induced lightning shielding effect of overhead wire is small.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.589-592
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• 2011

Induced longitudinal voltage and induced noise voltage are used in the analysis on the power induction phenomenon and it is well known that these are in the subordinate relationship. But sometimes. there is a confusing situation that these voltages have not exact subordinate relationship in the actual measurement fields. So. we have analyze the correlation between induced longitudinal voltage and induced noise voltage by using tile actual measured data in the fields of 30 urban areas and 30 rural areas.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.10
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• pp.5148-5155
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• 2013

The induced voltage on the telecommunication cable generated by nearby electric railway system may bring about telecommunication errors and safety accidents. In order to reduce the induced voltage and to achieve communication reliability, the effect of the shield cables and the recent double-track railway systems on the inductive interference should be investigated. This paper analyzes the parameters which seriously influence the induced voltage on the telecommunication cables which run parallel with a AT-fed electric railway line, and provides a simulation-based approach to estimate the amount of the induced voltage. Simulation results indicate that the induced noise voltage generated by a double-track railway decreases by 18 % compared to that generated by a single-track railway, showing the screening effect by nearby track. The induced noise voltages on the 50%-shielded cable and 15%-shielded cable decrease to 1/8 and 1/15 of the induced voltage on the non-shielded cable, respectively. A meaningful shield effect is achieved and the induced voltage is minimized by the double-track railway and the shielded cable.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.2
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• pp.301-309
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• 1996

This paper estimates the electric field effect near 765[kV] AC double transmission line with numerical data. The induced voltage and current of a human and car under who kinds of phase arrangement are calculated when each of two objects is insulated or grounded. When the calculated results of the low-reactance and superposition phase arrangement are compared, it is proved that the induced voltage and current of the former are about 30 [%] smaller than that of the latter. The induced current of a human and car are less than 0.5[mA] which is about 10[%] less than that of the American National Standard Code. Also the induced voltage and current of dead lines by other live lines are calculated. Finally the effective number and position of shield wires to reduce the field in ground level are considered. charge simulation method and surface charge method are used to simulate the 2 or 3 dimensional transmission line model respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.291-292
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• 2008

This study used EPR's sheet and cable as a specimen, and measured residual voltage depending on the induced voltage, thickness of the sheet, and shape of the sheet and cable. The results of the study lead to the following conclusion: 1) The residual voltage increased in proportion to the induced voltage as time increases; 2) The residual voltage of the basic mixed specimen and practical mixed specimen increased as time increased; 3) The peak of the cable appeared earlier than that of the sheet in both of the basic mixed specimen and practical mixed specimen.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1956-1958
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• 2002

This paper reviews the calculation of induced voltage to a communication line from Power Transmission Line. Power lines, both overhead and underground, often run parallel to weak current lines, such as telecommunication, signal or data transmission systems or protection circuits. The coexistence of both systems in parallel over long lengths is accompanied by the possible induction of significant longitudinal voltage in the weak current line. In order to evaluate a precise induced voltage, this paper indicated problem about coefficient and numerical formula and present some induced voltage production technology standard application.

• Journal of Electrical Engineering and Technology
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• v.10 no.5
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• pp.2001-2008
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• 2015

This paper proposes the concept of FlexPCB(flexible Printed Circuit Board) conductive structure for electrodynamic bearings. It has three main advantages: easy “printing” of considerably thin conductive wires, resulting in potential reduction in stray eddy currents; realization of specific conductive configurations with high precision to optimize the eddy current flowing; simplicity in being wound to cylinders or hollow cylinders of different diameters. To verify this new concept, the FlexPCB conductive structure was manufactured, an axial electrodynamic bearing test rig was built and the conductive structure's induced voltage was measured along the axial displacements from 0mm to 56mm at three rotating speeds. The finite element method was used to calcuatlate the flux density of electrodynamic bearing and induced voltage of the FlexPCB conductive structure. The experimental results are compared with the results from the FEM calculation. It is concluded that the measured and calculated induced voltages have consistency in the middle part of the bearing.