• Journal of Power Electronics
• /
• v.16 no.3
• /
• pp.1218-1225
• /
• 2016

The avionic battery discharge regulator (BDR) plays an important role in a power-conditioning unit. With its merits of high efficiency, stable transfer function, and continuous input and output currents, the non-isolated Weinberg converter (NIWC) is suitable for avionic BDR. An improved peak current control strategy is proposed to achieve high current-sharing accuracy. Current and voltage regulators are designed based on a small signal model of a three-module NIWC system. The system with the designed regulators operates stably under any condition and achieves excellent transient response and current-sharing accuracy.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2002.07b
• /
• pp.1088-1092
• /
• 2002

This paper introduces that domestic animals can be effectively administered with an individual recognition system. The system was constructed in original code transmitter, receiver, personal computer, micro-processor, and RS485 telecommunications module. In the individual recognition system. the signal including encoded information about a milk-cow was transmitted from an original code transmitter to a micro-processor through RS485 telecommunications module. The transmitted signal was successfully displayed in a personal computer.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.430-433
• /
• 2003

Air-operated valve is one of principal valves that are using to control fluid flow. A period diagnosis for safety of power plants is necessary. But there are many difficulties such as economic loss caused by intone of high cost devices and a matter hard to deal with users. In this study we developed the diagnosis system that usersofpower plants are easy to handle. The diagnosis system is composed of database module, reliability analysis module, design safety nodule and diagnosis test and evaluation module.

• Proceedings of the KIPE Conference
• /
• 2015.07a
• /
• pp.289-290
• /
• 2015

본 논문에서는 고효율, 저가격의 400W급 태양광 Module Integrated Converter (MIC)를 소개한다. 제안하는 MIC는 Interleaved flyback 토폴로지를 기반으로, 계통 주기 내에서 DCM과 CCM의 모든 동작 영역을 활용할 수 있게 설계되어 도통 손실 및 전력 용량을 개선한다. 또한 새로운 출력 제어 전류 알고리즘을 통해 기존의 Flyback의 CCM 영역에서의 제어문제를 해결하여 개발된 Flyback MIC의 실효성을 획득한다. 최종적으로 400W급 시제품을 제작하여 타당성 검증 및 결과를 제시한다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.34 no.1
• /
• pp.44-49
• /
• 2021

Recently, infrared (IR) and near-infrared (NIR) light-emitting diodes (LEDs) were widely used for home medical applications owing to its low output power and wide exposed area for curing. For deep penetration of the light under the skin, multiple LEDs with wavelengths of 700~10,000 nm were located on a flexible printed circuit board. When multiple wavelengths of LEDs were soldered on a circuit board, the lifetime of LED module highly depends on LEDs with a short lifetime. The mean time to failure (MTTF) was able to calculate with the experimental results under high temperature and the Arrhenius model. The results of this study could help companies to approve the warranty of LED modules and its product.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.10 no.3
• /
• pp.248-256
• /
• 2005

This paper presents the design method of the DC/DC converter using flat transformer which is suitable for midium or large capacity and high density power supply. Flat transformer module is composed and manufactured of multi-transformers in parallel and has a number of parallel single turn secondary windings. Therefore, its leakage inductance is highly decreased and it is more suitable for high frequency operation than conventional one. In this paper, we manufactured and tested 750W AC/DC converter with variable output powers to verify the performance of the flat transformer.

• ETRI Journal
• /
• v.41 no.6
• /
• pp.820-828
• /
• 2019

A highly reliable conductive adhesive obtained by transient liquid-phase sintering (TLPS) technologies is studied for use in high-power device packaging. TLPS involves the low-temperature reaction of a low-melting metal or alloy with a high-melting metal or alloy to form a reacted metal matrix. For a TLPS material (consisting of Ag-coated Cu, a Sn96.5-Ag3.0-Cu0.5 solder, and a volatile fluxing resin) used herein, the melting temperature of the metal matrix exceeds the bonding temperature. After bonding of the TLPS material, a unique melting peak of TLPS is observed at 356 ℃, consistent with the transient behavior of Ag₃Sn + Cu₆Sn₅ → liquid + Cu₃Sn reported by the National Institute of Standards and Technology. The TLPS material shows superior thermal conductivity as compared with other commercially available Ag pastes under the same specimen preparation conditions. In conclusion, the TLPS material can be a promising candidate for a highly reliable conductive adhesive in power device packaging because remelting of the SAC305 solder, which is widely used in conventional power modules, is not observed.

• Journal of information and communication convergence engineering
• /
• v.1 no.1
• /
• pp.39-43
• /
• 2003

The technology required to advance the state of the art of ultra-high-intensity excimer amplifier construction to the 100 J/100fs output pulse level is identified. The preliminary design work for very large final amplifier pumped by electron beam module is described, and key design problems and approaches are presented and discussed in detail based on the recent experimental and theoretical results.

• Nuclear Engineering and Technology
• /
• v.54 no.10
• /
• pp.3595-3603
• /
• 2022

Nuclear safety-class DCS is used for nuclear reactor protection function, which is one of the key facilities to ensure nuclear power plant safety, the maintenance for DCS to keep system in a high reliability is significant. In this paper, Nuclear safety-class DCS system developed by the Nuclear Power Institute of China is investigated, the model of reliability estimation considering nuclear power plant emergency trip control process is carried out using Markov transfer process. According to the System-Subgroup-Module hierarchical iteration calculation, the evolution curve of failure probability is established, and the preventive maintenance optimization strategy is constructed combining reliability numerical calculation and periodic overhaul interval of nuclear power plant, which could provide a quantitative basis for the maintenance decision of DCS system.

• Proceedings of the IEEK Conference
• /
• 1999.11a
• /
• pp.871-874
• /
• 1999

We propose a low complexity M-D(multidimensional) TCM decoder VLSI architecture for ADSL System. We use the shared subset decoder module by modifying the whole decoding procedure. We reduce power consumption by using the MSA (modulo set area) operation, which removes multiplication in 4D metric calculation. Also the proposed TCM decoder reduces chip area. It can be adopted in high-speed xDSL system.