• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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• pp.115-117
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• 1988

The algorithm presented here achieves mathematically better decoupling of the MW-$\theta$ and MVARE Calculations by applying linear transformations to load flow equation on paired initial power. The linear transformations to decouple Jacobian matrix prove to be highly profitable considering both Convergence characteristics and computation time per iteration to those required by the FDLF, because the decoupling does not rely on the assumption that the transmission lines have high X/R ratios.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2000년도 추계 기술심포지움 논문집
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• pp.23-27
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• 2000

Simultaneous Switching Noise (SSN) propagated through parallel power and ground planes in high-speed multilayer printed circuit boards (PCBs) causes malfunction of both digital and analog circuits. To reduce SSN, decoupling capacitors are generally used in the PCBs. In this paper, we improve the equivalent circuit model of decoupling capacitor in high-frequency range to analyze the effect of SSN reduction accurately. The analysis is performed by the microwave and RF design system (MDS) method and the finite difference time domain (FDTD) method. We compared the results by the ideal capacitor model with those by the proposed model.

• 대한전자공학회논문지SD
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• 제41권1호
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• pp.71-80
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• 2004

본 논문에서는 집적회로 패키지에 기인한 노이즈를 해석할 수 있는 새로운 SSN모델을 보인다. 기존의 디커플링 커패시터를 고려하지 않은 회로모델은 과도하게 SSN을 예측한다는 것을 보였으며, 디커플링 커패시터가 포함된 패키지 회로모델을 통하여 새로운 SSN 모델을 제안하였다. 새롭게 제안된 SSN 모델은 0.18um공정(TSMC 0.18um공정)을 사용하여 다양한$\cdot$회로설계 변수(입력상승시간, 패키지 인덕턴스 및 동시 스위칭 개수)의 변화에 따라 HSPICE 시뮬레이션과 정확히($5\%$ 이내에서) 일치한다는 것을 검증하였다.

• 한국철도학회논문집
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• 제10권2호
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• pp.96-102
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• 2007

This paper presents a study on the control of a power quality compensating equipment of electrical railway built in small-scaled to preliminary research. Because this compensating equipment is very complicated power electronics system, consisting of a scott transformer as a power source, four single phase inverters interconnected with DC-link capacitors and various electrical apparatuses, multiple controllers and control algorithms with high performance and reliability are needed. The major function of the compensating equipment is to manage reactive and active powers by using the four single phase inverters, so, the main control effort is focused on the power flow control which realized through the decoupling current control of the four inverters. Overall control system is designed with object oriented and analyzed on a Simulink window. The simulation results show that the design scheme is very effective for a complicated control system and the proposed controller has good performance.

• Journal of Power Electronics
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• 제12권6호
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• pp.1003-1010
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• 2012

Recent power electronics and variable-frequency motor drive technologies have been applied to air conditioners to improve efficiency and power density. However, the mechanical vibrations and acoustic noise resulting from the compressor still remain as a serious problem. This paper presents the development and implementation of an online disturbance state-filter for the suppression of multiple unknown and time-varying vibrations of air conditioning systems. The proposed design has a form of the state-filter based on a Luenburger-style closed-loop speed observer. An active vibration decoupling strategy with an estimated disturbance is provided, which manipulates a motor torque command. Since the proposed estimation does not require any additional transducers or hardware for obtaining real-time information upon disturbances, it is suitable for retrofitting industrial air conditioners.

• 전력전자학회논문지
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• 제26권4호
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• pp.277-284
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• 2021

A single and three phase-compatible single-stage EV charger without electrolytic capacitor is proposed in this study. DC battery-charging current is inherently guaranteed in the three-phase grid due to three output currents with a phase shift of 120° between each other. The proposed EV charger can provide a DC battery charging current for the single-phase grid through the integrated active power decoupling circuit without using additional switches. The proposed EV charger ensures ZVS turn-on of all switches with wide grid and battery voltage ranges. The 11 kW prototype of the proposed EV charger demonstrates a peak efficiency of 97.01% and a power density of 5.58 kW/L.

• ETRI Journal
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• 제32권2호
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• pp.265-272
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• 2010

To supply a power distribution network with stable power in a high-speed mixed mode system, simultaneous switching noise caused at the multilayer PCB and package structures needs to be sufficiently suppressed. The uni-planar compact electromagnetic bandgap (UC-EBG) structure is well known as a promising solution to suppress the power noise and isolate noise-sensitive analog/RF circuits from a noisy digital circuit. However, a typical UC-EBG structure has several severe problems, such as a limitation in the stop band's lower cutoff frequency and signal quality degradation. To make up for the defects of a conventional EBG structure, a partially located EBG structure with decoupling capacitors is proposed in this paper as a means of both suppressing the power noise propagation and minimizing the effects of the perforated reference plane on the signal quality. The proposed structure is validated and investigated through simulation and measurement in both frequency and time domains.

• Journal of Power Electronics
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• 제9권1호
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• pp.68-73
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• 2009

Automotive inverters may require current sensors for motor torque control, especially, in applications of hybrid electric vehicles or fuel cell vehicles. In this paper, to achieve a compact, integrated and low cost current sensor, a hall current sensor without magnetic core is introduced for integrating an automotive inverter. The compactness of the current sensor is possible by using integrated magnetic concentrators based on the Hall effect. Magnetic fields caused by three-phase currents are analyzed and a magnetic shield design is proposed for decoupling the cross-coupled field. It offers galvanic isolation, wide bandwidth (>100kHz), and accuracy(< 1%). Using 2D FEM analysis, its performance is demonstrated with design parameters at a U-shaped magnetic shield. The proposed coreless current sensor is tested with rated current to validate the linearity and accuracy.

• 한국콘텐츠학회논문지
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• 제17권4호
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• pp.48-62
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• 2017

거대기업들의 분식회계와 비윤리적인 기업경영, 리더십의 부재를 지켜보면서 본 연구는 팀장의 윤리적 리더십이 팀원들의 역할 내 행동과 긍정심리자본에 미치는 영향력을 실증적으로 규명하고 경영진 괴리현상과 개인 괴리현상의 조절효과를 분석하고 있다. 팀을 이끌어가고 있는 팀장의 윤리적 리더십이 팀원들에게 제대로 받아들여짐으로써 긍정적인 성과를 가져올 수 있지만 조직의 최종의사결정자인 최고경영진이 조직의 미션과 일치되지 않는 행동을 보이는 경영진 괴리현상을 인지할 경우, 윤리적 리더십의 긍정적인 효과가 방해를 받거나 상쇄될 가능성이 있다. 또한 팀원들 자신의 행동이 조직의 미션과 일치되지 않는 개인 괴리현상을 인지할 경우에도 윤리적 리더십의 효과는 감소될 수 있다는 점에서 윤리적 리더십과 괴리현상의 상호작용효과를 분석하는 것은 중요하다. 은행, 반도체회사, 대학병원에 종사하고 있는 922명의 종업원 데이터를 분석한 결과, 팀장의 윤리적 리더십은 팀원들의 역할 내 행동과 긍정심리자본에 긍정적인 영향을 미치는 것으로 나타났다. 또한 경영진 괴리현상의 조절효과가 검증됨으로써 조직의 미션과 다르게 행동하는 경영진 괴리현상이 윤리적 리더십의 긍정적인 효과를 감소시키는 것으로 나타났다. 이와 같은 연구결과를 바탕으로 윤리적 리더십과 경영진 괴리현상이 조직의 실무자에게 주는 함의점에 대해 논의하였다.

• 전력전자학회논문지
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• 제4권1호
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• pp.43-49
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• 1999

본 연구에서는 비선형 시스템을 선형 시스템으로 변환시키는 미분기하이론에 기초를 둔 비선형 궤환 선형화 기법을 유도전동기와 같은 비선형 시스템의 제어에 응용함으로써 완전한 비간섭 시스템을 얻을수 있음을 보였다. 또한, 엘리베이터와 같은 부하의 정속도 운전시 효율제어를 위해 회전자 자속을 변화시킬 때 이의 영향을 받아 값이 바뀌는 인덕턴스와 온도에 따라 가장 변화가 심한 회전자저항을 위한 추정알고리즘을 제안하고 이의 성능을 평가해 보기 위하여 시뮬레이션과 실험을 수행하였다.