• JSTS:Journal of Semiconductor Technology and Science
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• 제16권6호
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• pp.873-879
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• 2016

A charge pump circuit with very short turn-on time is presented for minimizing reference spurs in CMOS PLL frequency synthesizers. In the source switching charge pump circuit, applying proper voltages to the source nodes of the current source FETs can significantly reduce the unwanted glitch at the output current while not degrading the rising time, thus resulting in low spur at the synthesizer output spectrum. A 1.1-1.6 GHz PLL synthesizer employing the proposed charge pump circuit is fabricated in 65 nm CMOS. The current consumption of the charge pump is $490{\mu}A$ from 1 V supply. Compared to the conventional charge pump, it is shown that the reference spur is improved by dB through minimizing the turn-on time. Theoretical analysis is described to show that the measured results agree well with the theory.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1547-1549
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• 1996

The electrical and optical switching characteristics of gold-doped silicon p-i-n diodes have been investigated. The device shows a dark switching voltage of about 500 V. The switching voltage decreases rapidly when the illumination level is increased. The differential sensitivity of optical gating over linear region is $d(V_{Th}/V_{Tho})/dP_{Ph}$=0.25/uW. The turn-on delay time and the turn-on rise time decrease with increasing optical pulse power. The turn-off delay and the fall time are negligible.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.725-726
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• 2008

This paper deals with characteristic analysis of Linear Switched Reluctance Motor (LSRM) according to switching condition. When approved current in each phase by decided position, we made sure current and voltage according to turn-on, turn-off. In dynamic simulation of LSRM, through an experiment, we decided turn-on position of inductance profile. Also, we presented dynamic characteristic analysis model which is consisted at motor and sensor signal part, etc., and substitute circuit constant that get using magnetic equivalent circuit method, we confirmed current and voltage waveform.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.668-676
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• 1998

A passive energy recovery snubber for high-power-factor boost rectifier, in which the main switch is described in terms of the equivalent circuits that are operational during turn-on and turn-off sequences. These equivalent circuits are analyzed so that the overshoot voltage across the main switch, the snubber current, and the turn-off transition time can be predicted analytically. The main switch combined with proposed snubber can be turned on with zero current and turned off at limited voltage stress. The high-power-factor boost rectifier with proposed snubber is implemented, and the experimental results are presented to confirm the validity of proposed snubber.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.555-557
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• 2006

This paper represent improved On-line Turn off Angle control schemes for switched reluctance motors based on current control. For the purpose of the finding optimal commutation switching angle point, it is utilized him on and turn off position calculation with inductance vs. current vs. flux linkage analysis method. The goal of proposed paper is the maximization of the energy conversion per stroke and maximizing efficiency and obtaining approximately flat-topped current waveform. The proposed control scheme is demonstrated on a prototype experimental system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
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• pp.358-360
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• 1999

This paper presents a new soft-switching partial series resonant DC/DC converter (PSRC) with zero-voltage on/off simultaneously, suitable for application in the high power and high frequency switching. The proposed converter has not only advantages of the conventional PSRC but also zero-voltage turn-on and turn-off of the main switches for the entire load ranges by adding the auxiliary circuit, and zero-voltage-switching (ZVS) turn-on of the auxiliary switches. The operation principles of the new converter are explained in detail and the several interesting simulation and experimental results verify the validity of the proposed circuit.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2002년도 제25회 KOSCI SYMPOSIUM 논문집
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• pp.57-64
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• 2002

This paper describes the results of a series of experiments executed by using two pilot-scale oxv-fuel burners are designed for maximum capacity of 50,000 kacl/hr, 300,000 kcal/hr and installed in the test furnace. The effects of turn-down ratio, excess oxygen ratio, nozzle exit velocity, injection angle, swirl vane angle and inlet oxygen temperature on the combustion characteristic are investigated. Temperature distributions are measured using R-type and Molybdenum sheathed C-type thermocouple. The results showed that maximum temperature and mean temperature increase with the increase of turn-down ratio and inlet oxygen temperature. The maximum flame temperature was increased about 35% compared to the case of equivalent air operated condition. In addition, Optimum excess oxygen ratio and nozzle characteristics are obtained for this oxy-fuel glass melting furnace.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2120-2122
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• 1999

$SF_6$ gas has been widely used the gas insulated transmission line, gas insulated transformer and gas insulated substation and Polyester film used as the turn insulation with other material. $SF_6$ gas has been actively studied in domestic and foreign countries. In general, when dielectric surface electric field exceed any electric field strength on air, corona discharge is occurred from the dielectric surface. This paper presents the insulation strength of turn insulation of $SF_6$-PET film studied under application of AC voltage, constitute of the plane to plane with PET Film. The results obtained in experimental are summarized that Partial Discharge Initial Voltage(PDIV) of turn insulation depend on gas pressure, but Breakdown Voltage(BDV) did not depend on gas pressure.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.1061-1062
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• 2006

This paper represent improved On-line Turn off, commutation Angle control schemes for switched reluctance motors based on current control. For the purpose of the finding optimal commutation switching angle point, it is utilized turn on and turn off position calculation with inductance vs. current vs. flux linkage analysis method. The goal of proposed paper is the maximization of the energy conversion per stroke and maximizing efficiency and obtaining approximately flat-topped current waveform. The proposed control scheme is demonstrated on a simulation experimental result.

• 한국자기학회지
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• 제19권6호
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• pp.222-226
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• 2009

기존의 평판형 전자기 엑츄에이터에 쇼티드 턴을 적용한 새로운 형태의 평판형 전자기 엑츄에이터를 제안하였다. 기존의 평판형 전자기 엑츄에이터에서 발생하는 인덕턴스에 의한 초기응답 지연현상을 줄이기 위해 본 논문에서는 기존의 엑츄에이터의 요크와 요크 사이에 중간요크(center yoke)를 추가하고, 쇼티드 턴을 적용한 새로운 형태의 평판형 전자기 엑츄에이터를 제안 하고, 상용 자기장 해석 프로그램인 MAXWELL을 이용한 시뮬레이션을 통해 동적 성능 향상을 검증 하였다.