• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2008년도 춘계학술대회 논문집
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• pp.415-418
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• 2008

This paper presents an innovative prototype of a new conceptual electromagnetic induction-based fluid beating appliance using voltage-fed type scries capacitor-compensated load resonant high-frequency IGBT inverter with a phase-shifted PWM and a power factor correction schemes. Its operating characteristics in steady-state are illustrated including unique features and evaluated on the basis of its computer simulation and experimental results of 10kw breadboard appliance for hot water producer and superheated steamer. The promising cost effective inverter-fed boiler appliances for electromagnetic induction-heated type fluid-heating in the pipeline systems are proposed for induction-heated boiler, super heat steamer, high temperature water producer, hot gas producer and metal catalyst heating for exhaust gas cleaning in engine, which are more suitable and acceptable for industrial, chemical, and consumer energy utilization for household and business from a practical point of view.

• 예술인문사회 융합 멀티미디어 논문지
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• 제8권11호
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• pp.215-222
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• 2018

본 논문에서는 슈퍼커패시터를 적용한 에너지 저장장치에 대해서 연구하였다. 납축전지등을 사용하였던 기존방식과는 다르게 슈퍼커패시터를 사용하여 고출력을 달성할 수 있으며, 이러한 특징으로 인하여 연구된 저장장치는 비상전원용 전력을 공급할 수 있을 뿐만 아니라, 전력품질 개선이나 짧은 순간에 큰 출력을 요구하는 고속 기동용 모터등의 전원시스템으로도 사용이 가능한 장점이 있다. 에너지변환 시스템은 양방향 인버터와 컨버터로 구성되어 고속, 고출력의 충전, 방전을 수행할 수 있는 장점도 있다. 양방향 인버터를 이용한 two loop 제어기 설계 방법이 제시되었고, 실험과 제작을 통해 설계 방법의 정합성을 입증하였다. 설계 순서는 먼저 상태공간 평균화 기법과 Decoupling 기법을 이용하여 선형화된 전달함수를 계산하였다. 다음 20% 오버슈트와 안정시간을 만족시키는 전류 제어기 설계를 한 후에 오버슈트 없는 전압과 10배 이상 느린 안정시간을 가지는 전압제어기를 설계한 후 단위계단응답 커브를 통해 원하는 설계특성이 나오는 지를 확인하는 과정으로 이루어진다. 설계된 제어기들은 계통과 단위 역률을 이루며 제어되기 때문에 전력품질 향상을 이룰 수 있으며, 빠른 응답특성과 정상상태 오차를 0으로 만들 수 있는 우수한 제어특성을 가지고 있음을 확인할 수 있었다.

• 전기학회논문지
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• 제58권7호
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• pp.1386-1392
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• 2009

An analysis is presented for super-high-speed optical demodulation by an avalanche photodiode(APD) with electric mixing. A normalized gain is defined to evaluate the performance of the optical mixing detection. Unlike previous work, we include the effect of the nonlinear variation of the APD capacitance with bias voltage as well as the effect of parasitic and amplifier input capacitance. As a results, the normalized gain is dependent on the signal frequency and the frequency difference between the signal and the local oscillator frequency. However, the current through the equivalent resistance of the APD is almost independent of signal frequency. The mixing output is mainly attributed to the nonlinearity of the multiplication factor. We show also that there is an optimal local oscillator voltage at which the normalized gain is maximized for a given avalanche photodiode.

• 조명전기설비학회논문지
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• 제22권11호
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• pp.23-29
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• 2008

This paper presents a new conceptual electromagnetic induction eddy current based stainless steel plate spiral type heater for heat exchanger or dual packs heater in hot water system boiler steamer and super heated steamer, which is more suitable and acceptable for new generation consumer power applications. In addition, an active clamping quasi-resonant PWM high frequency inverter using trench gate IGBTs power module can operate under a principle of zero voltage soft commutation with PWM is developed and demonstrated for a high efficient induction heated hot water system and boiler in the consumer power applications. This consumer induction heater power appliance using active clamping soft switching PWM high frequency inverter is evaluated and discussed on the basis of experimental results.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2008년도 춘계학술대회 논문집
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• pp.325-328
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• 2008

This paper presents a new conceptual electromagnetic induction eddy current-based stainless steel plate spiral type heater for heat exchanger or dual packs Heater in hot water system boiler steamer and super heated steamer, which is more suitable and acceptable for new generation consumer power applications. In addition, an active clamped quasi resonant PWM high frequency inverter using trench gate IGBTs power module can operate under a principle of zero voltage soft commutation with PWM is developed and demonstrated fora high efficient induction heated hot water system and boiler in the consumer power applications This consumer induction heater power appliance using active clamp soft switching PWM high-frequency inverter is evaluated and discussed on the basis of the simulation and experimental results.

• 융합신호처리학회논문지
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• 제7권2호
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• pp.81-86
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• 2006

본 논문에서는 새로운 개념의 공정 검출 회로를 제안하였다. 제안된 공정 검출 회로는 장채널 트랜지스터와 최소의 배선폭을 갖는 단채널 트랜지스터 사이의 공정변수의 차이를 비교한다. 이 회로는 공정 변이에 따라 발생하는 캐리어 이동도의 차이를 이용하여 이에 비례하는 차동 전류를 생성해 낸다. 이 방법에서는 고 이득 연산증폭기를 사용한 궤환 회로를 구현함으로써 두 개의 트랜지스터의 드레인 전압이 같아지도록 유지한다. 또한, 본 논문은 제안한 자기-바이어스 슈퍼 MOS 복합회로를 이용하여 고 이득 자기-바이어스 rail-to-rail 연산증폭기를 설계하는 새로운 방법을 소개한다. 설계된 연산증폭기의 이득은 단상의 $0.2V{\sim}1.6V$ 공통모드 범위에서 100dB 이상으로 측정되었다 최종적으로, 제안한 공정 검출 회로는 차동 VCO 회로에 직접 적용하였으며, 설계된 VCO 회로를 통해서 공정 검출 회로가 공정 코너들을 성공적으로 보상하고 광범위한 동작 영역에서 안정된 동작을 수행함을 확인할 수 있었다.

• 전기학회논문지
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• 제67권8호
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• pp.1113-1118
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• 2018

Protection in HVDC(High Voltage Direct Current) have the very fast velocity of fault detection. Because Fault in HVDC has the fast propagation, large currents, high interruption cost. The focus to velocity caused possibility of errors like a detection error like a high impedance fault. In this paper, Proposed complex composition for get the reliability and velocity. That used SFCL(Super Conducting Fault Current Limiter), Protection Zone and DTS(Distributed Temperature Sensing). The SFCL was detect the fault by quench and DTS&Protection Zone were perceive the detect by variation too. To examine the proposed method, PSCAD/EMTDC simulated. The results of simulation, proposed methods could the detect of fault to whole HVDC line. And that improved the reliability of fault clearing.

• 대한산업공학회지
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• 제38권3호
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• pp.220-226
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• 2012

The Electric discharge machining (EDM) process is used to minimize the difference between designed feature and machined feature while the most workpiece is removed through the cutting processes. The tiny-deep hole machining and perpendicular wall machining in mold and die are good applications of EDM. Among EDM equipment, the super drill uses the hollowed electrode to eliminate the debris which causes the second discharge with the electrode and degrades the machining quality. Through the hollow, the high pressured discharge oil is supplied to remove the debris together with the spindle rotation. The thin-hollow electrode tends to easily wear out compared to the sold die-sinking electrode and its wear rate is might not allowed to monitor in real time during discharging. Up to now, the wear amount is measured by off line method, which leads machining time to increase because the hole pass-through moment can be check by visual (manually) with the extra tool path. Therefore, this study suggests the attractive method to evaluate the hole pass-through moment in which the gap voltage and z-axis encoder pulse are monitored to predict the moment. The commercial super drill is used to validate the proposed method and the experiment is carried out.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 A
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• pp.267-270
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• 2003

This paper proposes high performance $8{\times}8$ multiplier using current-mode quaternary logic technique. The multiplier is functionally partitioned into the following major sections: partial product generator block(binary-quaternary logic conversion), current-mode quaternary logic full-adder block, quaternary-binary logic conversion block. The proposed multiplier has 4.5ns of propagation delay and 6.1mW of power consumption. Also, this multiplier can easily adapted to binary system by the encoder, the decoder. This circuit is simulated under 0.35um standard CMOS technology, 5uA unit current, and 3.3V supply voltage using Hspice.

• 대한조선학회논문집
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• 제55권2호
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• pp.153-160
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• 2018

In order to develop the driving pump for High-speed Cavitation Tunnel(HCT) which can experiment the super-cavitating submerged body, KRISO decided on the pump specification, designed the mixed-flow pump on the basis of the existing pump data and predicted the performance of the design pump using commercial CFD code (CFX-10). After the manufacture and installation of the driving pump, KRISO conducted the trial-test for HCT, analyzed the pump performance and compared trial-test results to those of design stage. The trial-test items for the HCT driving pump are measurements of output current/voltage at the inverter of the driving pump and the flow velocity in the HCT test section. The trial-test results showed the decrease in the flow rate of about 4.6% and the increase in pump head of about 8%, compared with those of the pump prediction. After the trial-test, the performance of the driving pump is predicted using CFX-10 with measured flowrates and pump rotational velocities. Though there is some difference between trial-test and prediction results due to inadequate motor data, it is thought that the tendency is reasonable. It is found that CFX-10 is useful to predict a mixed-flow pump.