• Journal of Magnetics
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• v.17 no.3
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• pp.210-213
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• 2012

To detect the surface and the opposite side cracks on iron specimen under AC and DC magnetic fields, the planar inductive coil sensors were employed. When the induced signals were measured, the planar inductive coil sensor and the magnetic field source were lifted off about 2 mm from the top surface of the specimen. AC magnetic fields and DC magnetic fields were applied to the specimens by single straight Cu coil and NdFeB permanent magnet, respectively. The detected signals at crack positions were good coincidence with those of the simulation results.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.11
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• pp.103-112
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• 2011

This paper is tried to analysis the optical emission spectroscopy related to the position of inductive load coil and flow rates of methane and oxygen in the RF inductive plasma process. According to the position of load coil, peak of $H_{\alpha}$, $H_{\beta}$, and CH were appeared strongly at the middle position of the coil and it decreased both direction. The electron temperature was approximately 0.9[eV] at that position. Emission intensities of $H_{\alpha}$, $H_{\beta}$, and CH increased linearly by increasing input power. In addition, intensities of $H_{\alpha}$ and $H_{\beta}$ increased by increasing the flow rate of oxygen. It might be ascribed that the oxygen species were bonded with $C_nH_m$ by suppressing the combination with hydrogen atoms. Consequently, the optimal position of the inductive coil is decided to the intermediate position between 4th and 5th turns, the wanted carbon thin-film is possible to deposit by controlling flow rates of methane and oxygen.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.3
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• pp.173-178
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• 1999

In this paper, the characteristics of the shielded inductive superconducting fault current limiter(FCL) were simulated and analyzed. After determining parameters fo design for superconducting tube, iron core and primary coil, simple power system composed of shielded inductive FCL was simulated by the numerical analysis. The currents flowing under the fault condition could be limited below 50 A successfully. It was suggested that as the important factors of operational characteristics, the turns of primary coil and size of iron core play a major role for whether the shielded inductive SCFCL operated as inductive type or resistive type FCL.

• The Transactions of the Korean Institute of Power Electronics
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• v.24 no.2
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• pp.78-83
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• 2019

In this study, we analyze the structure of the transceiver coil in the inductive power transfer (IPT) system. In the IPT system, the transceiver coil design needs to have the highest magnetic coupling possible because of the relatively low magnetic coupling due to the large gap of distance without the core. The transmitting coil may be formed as a multi-layer type according to the distance between the transmitting and receiving coils if the receiving coil is configured as a multi-layer type on the inner structure of the receiving apparatus, thereby improving the magnetic coupling and system efficiency. We compare and analyze the coil magnetic coupling, and system efficiency according to the layer structure of the transmitting and receiving coils and verify the analysis by JMAG simulation. Experimental results show that the layer structure of the transceiver should be considered according to the inner space of the receiving device and the spacing distance.

• The Transactions of the Korean Institute of Power Electronics
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• v.27 no.6
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• pp.471-480
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• 2022

Inductive power transfer (IPT) is an attractive power transmission solution that is already used in many applications. In the IPT system, optimal coil design is essential to achieve high power efficiency, but the effective design method is yet to be investigated. The inductance formula and finite element method (FEM) are popular means to link the coil geometric parameters and circuit parameters; however, the former lacks generality and accuracy, and the latter consumes much computation time. This study proposes a novel coil design method to achieve speed and generality without much loss of accuracy. By introducing one-turn permeance simulation in each FEM phase combined with curve fitting and optimization by MATLAB in the efficiency calculation phase, the iteration number of FEM can be considerably reduced, and the generality can be retained. The proposed method is verified through a 100 W IPT system experiment.

• Journal of Korea Foundry Society
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• v.19 no.5
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• pp.393-402
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• 1999

The reheating of the billet in the semi-solid state as quickly and homogeneously as possible is one of the most important aspects. From this point of view, an optimal design of the induction coil is necessary. The objective of inductive coil designsi a uniform induction heating over the length of the billet. The effect of coil length, diameter, the gap between coil surface and billet and axial position of the billet on temperature distribution of billet has been investigated. These design parameters have an important effectiveness on the electro-magnetic field. Therefore, in this study an optimal coil design to minimize electromagnetic ed effect will be proposed by defining the relationship between billet length and coil length. In particular, key point in induction heating process is focussed on optimizing the coil design with regard to the size of the heating billet and the frequency of induction heating system. After demonstrating the suitability of an optimal coil design through the FEM simulation of the induction heating process, the results of the coil design are also applied to the reheating process to obtain a fine globular microstructure. Its considered that the reheating conditions of aluminum alloys for thixoforging and a new CAE model of the induction heating process are very useful for thixoforging practitioners including induction heating ones.

• JSTS:Journal of Semiconductor Technology and Science
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• v.9 no.4
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• pp.198-204
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• 2009

Inductive peaking using T-coils has been widely used in broadband I/O interfaces. In this paper, we analyze technical effects and limitations of the T-coil, and discuss several methods that can overcome these restrictions and improve the practicality of the T-coil. In particular we also propose and verify a circuit topology which can further extend bandwidth beyond the limit that conventional T-coil can achieve, and transfer 20 Gb/s data without noticeable distortion.

• Journal of electromagnetic engineering and science
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• v.8 no.1
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• pp.23-27
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• 2008

Magnetic coupling delivering wireless power in capsular endoscope(CE) is described in this paper. The characteristic of the magnetic flux linkage coil which generates the induced electromotive force(emf) under the magnetic field was analyzed. With the analyzed results, a magnetic flux linkage coil system was developed and tested. It was confirmed that the magnetic flux linkage coil system could supply more than 50 mW power at 125 kHz without changing the structure of conventional CE.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.8
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• pp.477-487
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• 2004

Helical magneto-cumulative generators(MCGs) are devices which convert explosive energy into electromagnetic energy. The electromagnetic energy supplied from an external circuit is amplified by an explosively driven metal conductor mounted at the center of a helical coil compressing magnetic flux between the conductor and the coil. To optimize the coil design, output properties of small-size helical MCGs were measured while varying design parameters; the number of coil sections, length of the sections, pitch in the sections, and type of copper wire. Dimensions of the coil were kept constant, 50 mm in diameter and 200 mm in length. The coil was fabricated by using enamel-coated copper wire of 1 mm in diameter. The highest energy amplification ratio and figure of merit were 52.5 and 0.81, respectively. from an helical MCG with initial inductance of 63.7 $\mu$H at initial energy of 0.152 kJ Based on the experimental and calculated results, empirical formulas capable of optimizing coil designs were derived. By using these formulas, pitch in each coil section can be obtained at an arbitrary inductive load for high energy amplification ratio and figure of merit.

• Journal of the Korea Convergence Society
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• v.6 no.2
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• pp.57-64
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• 2015

Inductive Power Transfer (IPT) systems have successfully been developed and used to replace traditional conductive power transfer systems where physical connection is either inconvenient or impossible, such as biomedical implants, undersea vehicles, and contactless battery chargers of robots, for providing power to movable or detachable loads. Inductive Coupling uses magnetic fields to transfer power. There is a primary coil, which generates a magnetic field. Then there is another secondary coil which is composed of a capacitor and a coil, the capacitor creates a circuit with the primary and secondary coils. This paper discusses design method and several implementation alternatives for wireless energy transmission systems. It presents realization examples for these alternatives. Wireless energy transmission is investigated in numerous convergence applications due to its simplicity and advantages.