• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.64-68
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• 2001

This paper presents an innovative prototype of a new conceptual electromagnetic induction heated type far infrared rays radiant heating appliance using the voltage-fed edge-resonant ZVS-PWM high frequency inverter using IGBTs for food cooking and processing which operates under a constant frequency variable power regulation scheme. This power electronic appliance with soft switching high frequency inverter using IGBTs has attracted special interest from some advantageous viewpoints of safety, cleanliness, compactness and rapid temperature response, which is more suitable for consumer power electronics applications.

• Journal of Aerospace System Engineering
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• v.15 no.5
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• pp.1-7
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• 2021

Demand for Ti-6Al-4V alloy is increasing in various industries because of its superior strength to weight and high-temperature strength properties. However, due to its low formability at room temperature, it is formed at high temperature, where its productivity and efficiency are low. The current high-temperature forming method has many limitations because it involves heating the specimen by heating the lower mold. It is expected that a process using high frequency induction heating, which can locally heat the product, can improve its productivity. In addition, time and cost can be saved if the process is simulated in advance with a reliable analysis. In this paper, we verified the reliability of the analysis by comparing the result of heating the specimen to 850 ℃ by high frequency induction heating and the temperature obtained through the co-simulation analysis.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.67 no.2
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• pp.82-89
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• 2018

This paper presents a novel prototype of dual mode control based phase shift ZVS PWM high frequency load resonant inverter with lossless snubber capacitors in addition to a single active auxiliary resonant snubber for electromagnetic induction heating(IH) foam metal based consumer fluid dual packs(DPA) heater. The operating principle in steady state and unique features of this voltage source soft switching high frequency inverter circuit topology are described in this paper. The lossless snubber and auxiliary active resonant snubber assisted constant frequency phase shift ZVS PWM high frequency load resonant inverter employing IGBT power modules actually is capable of achieving zero voltage soft commutation over a widely specified power regulation range from full power to low power. The steady state operating performances of this dual mode phase shift PWM series load resonant high frequency inverter are evaluated and discussed on the basis of simulation and experimental results for induction heated foam metal heater which is designed for compact and high efficient moving fluid heating appliance in the consumer pipeline systems.

• Proceedings of the KIEE Conference
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• 2001.07e
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• pp.30-32
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• 2001

Thomson's jumping ring was first exhibited by Elihu Thomson in 1887 and modified to include the floating variation by John A. Fleming in 1890. This vivid demonstration of electromagnetic induction is still used in physics classrooms to illustrate Faraday's and Lenz's laws and is the basis for linear actuators for sorvo-mechanical purpose as well as induction heating and rail guns. The jumping ring apparatus of the type described in this study is used to demonstrate and educate the effects of electromagnetic induction. To verify control algorithm, a sensor system and a data control/measurement system is required. The sensor system consist of photo-interrupted and encode circuit which is designed to take voltage according to the position of ring.

• Natural Product Sciences
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• v.24 no.2
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• pp.125-131
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• 2018

Berries and branches essential oil of Juniperus phoenicea were obtained by electromagnetic induction heating assisted extraction and by hydrodistillation with a yield varied from ($1.2{\pm}0.3$ to $2.4{\pm}0.7%$) and from ($0.6{\pm}0.1%$ to $1.1{\pm}0.1%$), respectively. forty eight compounds were identified representing (97.2 - 99.7%) of the oil. ${\alpha}$-Pinene (40.3 - 67.8%) and ${\delta}$-3-carene (13.5 - 26.8%) were the main compounds in berries and branches essential oils. Antioxidant activity was evaluated by three means: inhibition of 2, 2-diphenyl-1-picryl hydrazyl (DPPH) free radical, reducing power and ${\beta}$-Carotene/linoleic acid bleaching. The antioxidant activity of essential oils showed $IC_{50}$ ranging from $67.6{\pm}1.02{\mu}g/mL$ to $131.5{\pm}0.8{\mu}g/mL$ for berries and from $98{\pm}1.25{\mu}g/mL$ to $166.8{\pm}0.29{\mu}g/mL$ for the branches. Berries oil show more potent antioxidant activity compared to branches. This result is supported by the three methods investigated in this work.

• Journal of Aerospace System Engineering
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• v.11 no.3
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• pp.1-7
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• 2017

The applications of high-frequency induction heating has recently been studied in various industrial fields. In this study, induction heating is applied to a SCM440 specimen that is widely used in industry. The specimen was made up of a cylinder 20 mm in diameter and 160 mm long. An induction heating power supply module was used to generate heat in the cylinder at a high frequency (approximately 85 kHz) for 50 seconds. The temperature of the specimen was measured at the 150 mm length in 5 second intervals. Results such as joule heat and temperature are compared with the numerical model analysis using an electromagnetic-thermal co-simulation technique. The analytical model of the cylinder was modeled by considering the skin effect. The median measured temperature after induction heating was conducted for 50 seconds was $57.65^{\circ}C$, compared to a predicted analytical value of $57.27^{\circ}C$. Thus, the analytical results are in good agreement with the experimental results, and this model can predict the induction heating phenomenon numerically.

• Journal of the Institute of Convergence Signal Processing
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• v.19 no.2
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• pp.61-67
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• 2018

Welding preheating means that the surface of the base material to which the metal is welded before the main welding is heated to a constant temperature. It prevents the cracks of the adjacent influences such as reduction of material hardening degree by controlling the cooling rate, suppression of segregation of impurities, prevention of thermal deformation, and moisture removal. For this reason, it is a necessary operation for high quality welding. Induction heating is an efficient heating method that converts electric energy into heat energy by applying electromagnetic induction phenomenon. Compared with combustion heat generated by gas and liquid, it is clean, stable, and economical as well as rapid heating. It can be heated regardless of the shape, depth and material of the heating body by modifying the shape of the frequency and the coil with a simple structure. In this paper, we implemented a low frequency welding preheating system using induction heating technique and observed the temperature changes of coil resistance, inductance and automotive transmission parts according to the height of each transmission in winding coil for three kinds of automotive transmission parts. We confirmed that the change of current is a very important factor in the low frequency heating.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2943-2946
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• 2003

In this paper are described the indirect induction healed boiler and induction boated hot air producer using the voltage-fed series resonant high-frequency inverter which can operate in the frequency range from 20［kHz］to 50［kHz］. A specially designed induction heater, which is composed of laminated stainless assembly with many tiny holes and interconnected spot welding points between stainless plates, is inserted into the ceramic type vessel with external working coil. This working coil is connected to the inverter and turbulence fluid through this induction heater to moving fluid generates in the vessel. The operating performances of this unique appliance in next generation and its effectiveness are evaluated and discussed from a practical point of view.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.483-486
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• 2001

This Paper the state-of-the art indirect induction heated boiler and induction heated hot air producer using the voltage-fed series resonant high-frequency inverter whice can operate in the frequency range from 20kHz to 50kHz. A specially-designed induction heater composed of laminated stainless assembly with many tiny holes and interconnected spot welding points between stainless plates is inserted into the ceramic type vessel with external working coil connected to the inverter and tubelence fluid through this induction heater in moving fluid generates in the vessel. The operating performances of this unique appliance in next generation and its effectiveness are evaluated and discussed from a practical point of view.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.11
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• pp.15-22
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• 2008

This paper presents an innovative prototype of a new conceptual electromagnetic induction heated type far infrared rays radiant heating appliance using the voltage-fed quasi-resonant ZVS-PWM high frequency inverter using IGBTs for food cooking and processing which operates under a constant frequency variable power regulation scheme. This power electronic appliance with soft switching high frequency inverter using IGBTs has attracted special interest from some advantageous view points of safety, cleanliness, compactness and rapid temperature response, which is more suitable for consumer power electronics applications.