• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.2205_2206
• /
• 2009

Decoupling capacitor는 Power Plane의 특정 주파수 대역에서 Anti-resonance가 발생, 전력 전달에 저해가 될 시에 부착되어 원활한 전력전달을 하기위한 도구로 많이 사용되어 왔다. 하지만 De-cap(Decoupling capacitor)을 어느 위치에 어떤 용량으로 부착하여야 하는지 문제점이 제기되고 이를 해결하기 위해 무작정 설치하여 보는 번거로움이 있었다. 본 문에서는 De-cap의 적절한 사용법에 대한 방법과 Q-factor의 적용법을 제시한다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1991.10a
• /
• pp.73-78
• /
• 1991

In this study of stacked type film chip capacitor, the important parameters are heat-treated temperature, pressure and time. We measured the temperature dependence of dielectric properties and dissipation factor and the frequency dependence of dielectric properties, dissipation factor, ESR(Equivalent Series Resistance) and impedance in stacked type film capacitor. As a result, the best conditions of heat-treated temperature, pressure and time were proved to be 130$^{\circ}C$, 10kg/$\textrm{cm}^2$ and 3hrs, respectively.

• Proceedings of the KIPE Conference
• /
• 2014.07a
• /
• pp.13-14
• /
• 2014

This paper is proposed the PFC control method of boost converter using a charging current of the capacitor. Around AC voltage peak point, PFC operation is stopped and the charging current of the capacitor is flowed. The charging current of the capacitor and the switching current makes the AC input current. The 150[W] converter was confirmed high PF and low THD.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.17 no.4
• /
• pp.306-314
• /
• 2012

In case of the conventional DC-AC inverter using two DC-DC converters with unipolar output capacitor voltages, for generating the AC output voltage, the output capacitor voltages of its each DC-DC converter must be higher than the DC input voltage. To solve this problem, this paper proposes a single-phase DC-AC inverter using two embedded Z-source converters with bipolar output capacitor voltages. The proposed inverter is composed of two embedded Z-source converters with common DC source and output AC load. The AC output voltage is obtained by the difference of the output capacitor voltages of each converter. Though the output capacitor voltage of converter is relatively low compared to the conventional method, it can be obtained the same AC output voltage. Moreover, by controlling asymmetrically the output capacitor voltage, the AC output voltage of the proposed system is higher than the DC input voltage. To verify the validity of the proposed system, a DSP(TMS320F28335) based single-phase embedded Z-source DC-AC inverter was made and the PSIM simulation was performed under the condition of the DC source 38V. As controlled symmetrically and asymmetrically the output capacitor voltages of each converter, the proposed inverter could produce the AC output voltage with sinusoidal waveform. Particularly, in case of asymmetric control, a higher AC output voltage was obtained. Finally, the efficiency of the proposed system was measured as 95% and 97% respectively in case of symmetric and asymmetric control.

• Journal of IKEEE
• /
• v.18 no.4
• /
• pp.447-455
• /
• 2014

In this research, n-based 4H-MOS Capacitor was fabricated with PECVD (plasma enhanced chemical vapor deposition) process for improving SiC/$SiO_2$ interface properties known as main problem of 4H-SiC MOSFET. To overcome the problems of dry oxidation process such as lower growth rate, high interface trap density and low critical electric field of $SiO_2$, PECVD and NO annealing processes are used to MOS Capacitor fabrication. After fabrication, MOS Capacitor's interface properties were measured and evaluated by hi-lo C-V measure, I-V measure and SIMS. As a result of comparing the interface properties with the dry oxidation case, improved interface and oxide properties such as 20% reduced flatband voltage shift, 25% reduced effective oxide charge density, increased oxide breakdown field of 8MV/cm and best effective barrier height of 1.57eV, 69.05% reduced interface trap density in the range of 0.375~0.495eV under the conduction band are observed.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.11a
• /
• pp.613-614
• /
• 2008

• 전기의세계
• /
• v.41 no.4
• /
• pp.42-50
• /
• 1992

전자부품의 생산은 다량(대량) 생산을 해야 하는 특징을 갖는 산업으로 월산, 수 백만, 수 천만개를 한 공장에서 생산하고 있으며 이러한 이유로 실험실적으로는 우수한 성능의 Capacitor를 개발하여도 그것이 바로 상품으로 발전하는 것이 의문시 되는 것이며 무엇보다 새로운 Capacitor가 생산 기술적으로 쉽게 제작할 수 있는가를 동시에 검사해야하는 점이 중요하다 할 수 있다.

• Journal of Power Electronics
• /
• v.15 no.5
• /
• pp.1338-1347
• /
• 2015

DC injection is a critical issue in transformerless grid-connected inverters. DC injection control based on virtual capacitor has the advantages of low cost, low loss, high accuracy and easy implementation. In this paper, the principle of DC injection control based on virtual capacitor was analyzed. In addition, the applicable conditions, working process, steady state error and advantages were also discussed in detail. The design of the control parameters based on virtual capacitor was proposed in a grid-connected inverter with LCL filter. The robustness of the control parameters was also discussed. Simulation and experimental results verify the validity of the analysis and demonstrate that this research has a certain value in engineering applications.

• Proceedings of the KIPE Conference
• /
• 2013.11a
• /
• pp.75-76
• /
• 2013

최근 산업 및 경제의 급속한 발전으로 컴퓨터를 비롯한 전기 및 전자 장비, 통신기기, 반도체 장비 등 전기적 외란에 민감한 부하 설비의 사용이 급증하면서 전력 품질에 대한 관심이 고조되고 있다. 그 이유는 정밀 부하 장비들이 전압의 순간적 변동에 대하여 민감하여 이 문제로 인하여 파생되는 경제적 피해가 매우 크기 때문에 지속적인 관리가 필요하다. 이러한 문제 중에서 가장 빈번하게 발생하는 순간 전압 강하를 보상하기 위한 장치로 전기 이중 층 커패시터 (EDLC: Electric Double Layer Capacitor)를 에너지 저장장치로 사용한 순간전압강하 보상장치 (DVR: Dynamic Voltage Restorer) 시스템이 개발 되어 적용되고 있다. 본 논문에서는 현재 순간전압강하 보상장치에 사용되는 DVR 시스템에서 주로 사용되는 에너지 저장장치인 EDLC 보다 동일 사이즈 대비 에너지 밀도가 높은 하이브리드 커패시터를 적용하는 연구를 하고자 한다.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
• /
• 2002.02a
• /
• pp.31-34
• /
• 2002

In this study, thermal analysis of a thermal capacitor, which is used to cool the current lead in conduction-cooled superconducting systems, was done. The temperature difference across a thermal capacitor was calculated by using heat conduction equation. Effect of heat load, total thickness, height and length of a thermal capacitor on the temperature difference were show. Using the results in this work, total thickness and heat height of a thermal capacitor can be determined for given heat load and given temperature difference. This work can be used practically in design for every superconduction system using a current lead.