• Journal of Power Electronics
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• v.14 no.5
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• pp.834-841
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• 2014

This paper proposes new active switched-capacitor and switched-inductor Z-source inverter (ASC/SL-ZSI) topologies, which can provide a higher boost ability with a small shoot-through time. The proposed ASC/SL-ZSIs inherit all of the advantages of the classical ZSI, and have a stronger voltage boost inversion ability when compared with the classical ZSI. Thus, the output ac voltage quality is significantly improved. In addition, more cells can be cascaded in the impedance network in order to obtain a very high boost ability. The proposed topologies can be applied to photovoltaic or fuel-cell generation systems with low-voltage renewal sources due to their wide range of obtainable voltages. Both simulations and the experimental results are carried out in order to verify performance of the proposed topologies.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1459-1460
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• 2006

A new gas jet Z-pinch EUV light source having double gas jet electrodes has been developed. It has two nozzles and two diffusers. The EUV beam is collected from the side of pinch plasma, generated in between the inner nozzle and corresponding diffuser. A cylindrical shell of He gas curtain produced by the outer nozzle is specially designed for shielding the debris and suppressing the inner gas expansion. We have succeeded in generating EUV energy of 1.22 mJ/sr/2%BW/pulse at 13.5nm. The estimated dimension of EUV source is to be FWHM diameter of 0.07 mm and length of 0.34 mm, and FW 1/e2 diameter of 0.15 mm and length of 1.2 mm.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.303-304
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• 2014

This paper describes Four Switch Three-Phase Z-Source rectifier with reduced value capacitors. This configuration has some advantages in term of small size of the circuit. The rectifier has buck-boost function by shoot-through state. Also, the rectifier has the advantage of decreasing inrush current in start-up and transient states. In order to reduce harmonics PWM modulation technique with a variable index has been suggested. Four Switch Three-Phase Z-Source rectifier with reduced value capacitors can output stable DC. Principles and dynamics of the system are discussed in detail.

• Proceedings of the KIPE Conference
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• 2016.11a
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• pp.220-221
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• 2016

This paper proposes an active switched-capacitor embedded quasi-Z-source inverter (ASC-EqZSI) topology. In order to improve boost ability, One diode and one switch device are added in the qZSI impedance network, and a single dc source is shifted in series with the inductor in the impedance network. The performances of the proposed topology are verified with simulation and experimental results.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.153-154
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• 2011

본 연구에서는 인덕터-커패시터 필터로 구성되는 종전의 단방향 quasi Z-소스 컨버터의 승압 율을 증가시키는 방법을 제안하였다. 제안한 방법은 종전의 인덕터 필터 대신 다이오드를 필터로 이용하는 방법이다. 종전의 방식에 비해 동일한 출력전압에서 낮은 Z-임피던스 망의 커패시터 전압, 단락 비 등의 장점을 가진다. 타당성을 검증하기 위해 실험을 통해 출력전압, Z-임피던스망의 커패시터 전압 등을 비교 분석하였다.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.562-563
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• 2012

본 연구에서는 quasi Z-소스 DC-DC 컨버터와 LCCT Z-소스 DC-DC컨버터 특성을 가지고 있으면서 커패시터에 걸리는 전압과 전압 스트레스가 개선되는 improved LCCT Z-소스 컨버터(ZSDC)를 제안하였다. 제안한 improved LCCT ZSDC의 동작원리를 설명하고, 실험을 통하여 타당성을 고찰하였다.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.6
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• pp.767-781
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• 2013

In this paper, we proposes the AC input voltage and current sensorless control scheme to control the input power factor and DC output voltage of the three-phase Z-source PWM rectifier. For DC-link voltage control which is sensitive to the system parameters of the PWM rectifier, fuzzy-PI controller is used. Because the AC input voltage and current are estimated using only the DC-link voltage and current, AC input voltage and current sensors are not required. In addition, the unity input power factor and DC output voltage can be controlled. The phase-angle of the detected AC input voltage and estimated voltage, the response characteristics of the DC output voltage according to the DC voltage references, the FFT results of the estimated voltage and current, efficiency, and the response characteristics of the conventional PI controller and fuzzy-PI controller are verified by PSIM simulation.

• The Transactions of the Korean Institute of Power Electronics
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• v.17 no.5
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• pp.453-460
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• 2012

This paper proposes the method to design the parameters of an impedance network at three-phase QZSI(quasi Z-source inverter) by considering an equivalent series resistance (ESR) in the capacitor. The equations of both two capacitor voltages and two inductor currents are derived at three operating modes of the QZSI. The capacitor voltage ripples caused by the ESR in the capacitor at the transition state of operating modes are calculated. Based on the ripples of both the capacitor voltages and inductor currents, the optimal values of capacitor and inductor are designed. The simulation studies using PSIM and experimental results with DSP are carried out to verify the performance of design method.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.79-84
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• 1998

Tandem HPLC and atmospheric pressure chemical ionization(APcI) LC/MS method was used for the determination and confirmation of carbendazim residues in soybean sprout. Fluorescence(FL) detector was connected in tandem with the ultraviolet(UV) detector for dual detection of the carbendazim residue at the excitation and emission wavelength of 280 nm and 310 nm, respectively. The limit of detection for carbendazim was $0.1{\mu}g/kg$ sample. Recoveries of carbendazim from fortified soybean sprout at 0.5, 1.0 and 2.0 ppm were averaged 89.1%. Mass spectrometry using a APcI source confirmed the carbendazim residue in the soybean sprout sample. Fragmentation pattern on the APcI LC/MS spectrum of carbendazim was simpler than that from electron impact(EI) mass spectrum. Carbendazim produced 3 major ions including m/z 133, m/z 159 and m/z 191($M^{+}$). This method was sensitive enough to provide reliable and reproducible results for practical applications.

• Proceedings of the KIPE Conference
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• 2016.07a
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• pp.435-436
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• 2016

본 논문에서는 3상 Quasi Z-소스 AC/AC 전력변환기를 제안한다. 제안된 전력변환기는 3대의 단상 Quasi Z-소스 AC/AC 컨버터로 구성되어 있으며, 간단한 듀티 비 제어만으로도 동상 및 역상의 벅-부스트 출력 전압의 발생이 가능하다. 제안된 방식은 PSIM 시뮬레이션을 통하여 타당성을 확인하였다.