• Nuclear Engineering and Technology
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• 제42권3호
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• pp.305-312
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• 2010

The protection sequence of an AC/DC converter for an ITER PF coil system is developed in this study. Possible faults in the coil system are simulated and the results reflected in the design of a sequence to protect the coil and converter. The inductances of the current sharing reactors and thyristor numbers in parallel with the bridge arms are optimized with the designed protection sequence.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 학술대회 논문집
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• pp.245-249
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• 2005

This paper describes a boost converter cascaded high frequency link direct dc-ac converter suitable for fuel cell power sources. A new multi-loop control for a boost converter to reduce the low frequency input current harmonics drawn from fuel cell is proposed. A new PWM technique for the cycloconverter at the secondary to reject the low order harmonics in the output voltages is presented in detail.

• Carbon letters
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• 제4권1호
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• pp.14-20
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• 2003

Based on the previous results of the equilibrium and batch adsorptions, the removal efficiency of the two-step surface-modified activated carbon ($2^{nd}AC$) for heavy metal ions such as Pb, Cd, and Cr in fixed column was evaluated by comparing with that of the as-received activated carbon (AC) and the first surface-modified activated carbon ($1^{st}AC$). The order of metal removal efficiency was found as $2^{nd}AC$ > $1^{st}AC$ $\gg$ AC, and the efficiency of the $2^{nd}AC$ maintained over 98% from the each metal solution. Increase of the removal efficiency by the second surface modification was contributed to maintain favorable pH condition of bulk solution during adsorption process. The removal of the heavy metals on the $2^{nd}AC$ was selective with Pb being removed in preference to Cr and Cd in multicomponent solutions and slightly influenced by phenol as the organic material.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.674-677
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• 2000

Operational principles and driving characteristics of two well-known energy recovery circuits for ac plasma display panels Weber and Sakai circuits are investigated Efficiency of two circuits is analyzed by comparing the in put current of the circuits with different operating conditions. Driving characteristics of the Weber circuit are studied when the magnitude and pulse width of the driving boltage very.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2011년도 전력전자학술대회
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• pp.491-493
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• 2011

In this paper, a 15kW grid-connected battery charging and discharging system was proposed. AC regenerative device which consisted of an inverter using IGBTs and LCL filter transferred surplus power to grid. Phase locked loop(PLL) was used to resolve three-phase unbalance. AC regeneration function is able to improve the rate of energy use and the cost savings of energy is expected.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2014년도 추계학술대회 논문집
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• pp.103-104
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• 2014

This paper presents design method of 250[W] grid connected PV-AC module with decoupling and energy storage functions to select optimized passive elements for stable operation. The validity of design of optimized elements is verified by simulation results.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 전력전자학술대회 논문집
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• pp.438-443
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• 1998

A simple single-stage AC/DC forward converter with transformer magnetic energy feedback technique for power factor correction is proposed. The operational principle of the proposed converter is presented. The proposed converter gives the good power factor correction, low line current harmonic distortions, and tight output voltage regulation. The prototype shows high power factor with low line current harmonics.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제5B권3호
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• pp.277-282
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• 2005

This paper describes a step-down AC voltage regulator using an AC chopper and auxiliary transformer, which is a series connected to the main input. The detail design of the AC regulator, logic and PWM pattern of the AC chopper is described and the three-phase AC regulator using two single­phase AC choppers with a three transformer configuration is proposed for three-phase application. The proposed three-phase system has the advantages of lower system cost due to reduced switch number and gate driver circuit as well as advantages of decreased size and weight because it uses a series compensated scheme. The proposed AC regulator has many benefits such as fast voltage control, high efficiency and simple control logic. Experimental results indicate that it can be used as a step-down AC voltage regulator for power saving purposes very efficiently.

• 전력전자학회논문지
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• 제3권2호
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• pp.148-155
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• 1998

역률개선을 위한 변압기 자기에너지 궤환 기법을 이용한 새로운 단일 전력단, 단일 스위치 방식의 AC/DC 컨버터를 제안한다. 제안한 컨버터의 동작원리 및 해석을 수행하였다. 제안한 컨버터는 선전류 고조파 왜곡이 작으며 고역률 및 정확한 전압 조정이 가능하다. 실험모델은 단일 역률에 가까운 역률을 보이며 IEC 555-2를 충분히 만족시킨다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.220-225
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• 2007

The mechanical characteristics of AC4C Aluminum Casting Alloy were investigated by tensile test and impact test. Based on the tensile test' s result, we found that the yield strength of a high speed was about 10% higher than that of a low speed test and the maximum rupture strain mostly occurred in low speed tensile test. The impact energy of curved surface specimen was higher than that of plane surface specimen that can be measured in impact test.