솔리드 스테이트 스위치를 이용한 AC/AC 전압 변환기 설계

엄기홍 한국지식정보기술학회 2012 한국지식정보기술학회 논문지 Vol.7 No.1

Conventional power transformer adopted AC/DC and DC/AC converters in order to transform an AC voltage signal to another AC voltage signal. Recently, a few studies have been done on the direct conversion of an AC voltage to another AC voltage. In this paper, we present a digital controller system which can be applied to intelligent AC to AC voltage conversion to be used for an automatic voltage control by using only few transistors, replacing conventional electrical power transformers with solid state switches. We have designed an AC to AC voltage converter by adopting solid state switches in order to obtain an AC output power. It was possible to obtain highly efficient AC to AC converter by adopting AC power switches for pulse-width modulator(PWM). By introducing only few solid-state switches, high power solid state devices and networks of power distribution. The P-spice simulation showed the effective output of our converter we designed.

무인항공기를 위한 3.7V 단일 배터리 셀 고효율 전력관리 회로시스템

강운성,황선남,장호정,김현식,Kang, Woonsung,Hwang, Sunnam,Chang, Ho Jung,Kim, Hyun-Sik 한국마이크로전자및패키징학회 2017 마이크로전자 및 패키징학회지 Vol.24 No.3

본 논문은 드론의 체공시간 증대를 위해 고효율 전력관리 회로 및 시스템을 제안한다. 종래의 드론은 다수개의 직렬 배터리와 낮은 효율의 선형 레귤레이터 사용으로 무겁고 발열이 크며 이로 인한 전력누수 문제가 있었다. 본 논문에서는 3.7V 단일 Li-Po 배터리 셀을 사용할 수 있는 스위칭 방식의 승압형 DC-DC 전력변환 회로에 대한 연구를 다룬다. 본 연구를 통해 시제품 개발 결과 3.7V 입력, 5V 출력의 step-up regulation을 실현하였다. 또한 종래 선형 레귤레이터의 50% 수준이었던 전력효율 대비 최대 91.3% 효율과 $50^{\circ}C$ 이하의 표면온도를 달성하였으며, 0.02V/V 및 0.15V/A의 line/load regulation 성능을 측정으로 검증하였다. 본 연구결과를 통해 3.7V 단일 셀 배터리 사용으로 충방전을 위한 별도의 cell-balancing 회로가 필요하지 않게 되며, 높은 전력관리 효율로 드론의 체공시간을 획기적으로 개선시킬 수 있는 가능성을 확인하였다. This paper presents a highly efficient power management system for UAV-drones. For free from the battery cell-balancing issue, the proposed system allows the drone to utilize a single-cell Li-Po battery. To realize low-voltage input of 3.7V, the switch-mode step-up DC-DC converter is optimally designed with high power efficiency. The prototype DC-DC converter was implemented with an output voltage of 5V, which will be provided to digital parts of the drone. The power efficiency was measured to be max. 91.3% with low surface temperature. The measured line and load regulations were 0.02V/V and 0.15V/A, respectively. Thanks to the proposed power management system, the available time-to-fly of the drone is expected to be significantly extended in virtue of the enhanced power efficiency.

방열특성 제어를 위한 PWM 전류제어 기반 LED 모듈 개발

이승현(Seung-Hyun Lee),문한주(Han Joo Moon),허성범(Seong-bum Hue),최성대(Seong-Dae Choi) 한국기계가공학회 2015 한국기계가공학회지 Vol.14 No.6

This paper shows significant methods that improve the lifespan of LED modules as well as efficiently using an aluminum heat-sink for LED module in high power. It proposes a method that raises stability and lifespan to protect LED modules and the power unit when the LED module has been used for a long hours at high temperatures. During the research, we applied a method of pulse-width modulation (PWM) in order to prevent the phenomenon that the entire power of a system is turned off and the lifespan is reduced when the LED nodule reacts to the high temperatures. To protect the LED module and SMPS based on high efficiency, a temperature sensor is attached underneath the circuit board and the sensor measures the temperature of circuit board when the LED module is powered on. The electrical power connected to SMPS is controlled by PWM when the temperature of the LED module reaches a particular temperature.

Development of the High Input Voltage Self-Power for LVDC

Kim, Kuk-Hyeon,Kim, Soo-Yeon,Choi, Eun-Kyung,HwangBo, Chan,Park, Seong-Mi,Park, Sung-Jun The Korean Society of Industry Convergence 2021 한국산업융합학회 논문집 Vol.24 No.4

Distributed resources such as renewable energy sources and ESS are connected to the low voltage direct current(LVDC) distribution network through the power conversion system(PCS). Control power is required for the operation of the PCS. In general, controller power is supplied from AC power or DC power through switch mode power supply(SMPS). However, the conventional SMPS has a low input voltage, so development and research on high input voltage self-power suitable for LVDC is insufficient. In this paper, to develop Self-Power that can be used for LVDC, the characteristics of the conventional topology are analyzed, and a series-input single-output flyback converter using a flux-sharing transformer for high voltage is designed. The high input voltage Self-Power was designed in the DCM(discontinuous current mode) to reduce the switching loss and solve the problem of current dissipation. In addition, since it operates even at low input voltage, it can be applied to many applications as well as LVDC. The validity of the proposed high input voltage self-power is verified through experiments.

Analysis and Design Guide of Active EMI Filter in a Compact Package for Reduction of Common-Mode Conducted Emissions

Dongil Shin,Sungnam Kim,Geunseok Jeong,Jaesu Park,Joungwook Park,Ki Jin Han,Jingook Kim [Institute of Electrical and Electronics Engineers 2015 IEEE transactions on electromagnetic compatibility Vol.57 No.4

<P>A common-mode (CM) active filter was designed in a compact package to suppress CM conducted emissions at a switching mode power supply (SMPS). Based on the analytical expressions considering both stability and performance, the design and optimization rules for the proposed active filter have been presented. After verifying its performance by measurements using vector network analysis, the proposed filter was installed in a 200-W SMPS board with 64 and 110 kHz switching frequencies, demonstrating its usefulness by experiments. The performance degradation due to the magnetic saturation and the AEF grounding impedance was also analyzed and investigated.</P>

T8형 LED 조명장치 구동을 위한 정전압 정전류 출력전원장치 개발에 대한 연구

구춘근(Choon-Keun Koo),서대석(Dae-Seok Seo) 산업기술교육훈련학회 2014 산업기술연구논문지 (JITR) Vol.19 No.4

This Study focused on the development of Power supply equipment to supply the stabilized electric power over load conditions change. In this paper, the circuit of proposed SMPS designed for purposed to output the high quality of constant voltage and current. The proposed circuit with LNK 409 keep up the 95% of power factor and efficiency in spite of the load change. To improvement the above weak point, the developed SMPS unit monitored the voltage and current over 2 nd side of transformer for purposed to supply constant voltage and current additionally. The Experimental tests was applied the LED lighting of 46W.

디스플레이용 스위칭모드 전원장치의 단락 고장분석 검출기법

이재원(Jae-Won Lee),전태원(Tae-Won Chun) 대한전기학회 2016 전기학회논문지 Vol.65 No.7

This paper proposes techniques to diagnose short-circuit faults of both the diodes and power FET in switching mode power supply (SMPS) by using a simple analog tester. The diodes in full-bridge rectifier, power FET, switching transformer, and some sensors are modelled with resistor. The total resistance value measured at the input terminal of a SMPS is analyzed when the short-circuit faults of diodes in a full bridge rectifier or power FET are occurred. The short-circuit faults of one or two diodes in a full bridge rectifier, power FET, and both the diodes in a full bridge rectifier and power FET can be detected by a range of total resistance, which is measured by the analog tester. Through experiments, the theoretical analysis for total resistance under short-circuit faults can be verified.

A Comparative Study on Power System Harmonics for Offshore Plants

Deok-Ki Kim,Won-Ju Lee,Jong-Su Kim 해양환경안전학회 2016 海洋環境安全學會誌 Vol.22 No.7

해양구조물에 전기 안전사고가 급증하면서 전력시스템 고조파 분야가 최근 많은 관심 받고 있다. 이것은 주로 비선형 (또는 고조파 생성) 부하가 일반적인 산업플랜트 전력시스템에서 계속 증가되고 있기 때문이다. 해양플랜트에서는 전력시스템의 안전설계로 인하여 고조파 문제의 발생률은 낮지만, 고조파 문제에 대한 인식은 전력시스템 설계의 신뢰성을 향상시키는데 여전히 도움이 될 수 있다. 전력시스템에 고조파 문제가 드물게 발생되는 경우, 이는 생성된 고조파의 크기 혹은 전력시스템의 공진 때문이다. 이 고조파 비교분석에 관한 연구는 전력부하를 고려한 부유식 액화천연가스 생산·저장·하역 (FLNG) 설비의 하역 운전 시나리오에 대한 전기적인 구성으로 비교분석하였다. 전기적인 네트워크 구성은 전기적인 네트워크 부하 흐름에서 볼 수 있다. 본 연구는 해양플랜트 전력시스템의 안전을 보장하기 위해 전기 모터 시스템의 고조파 효율에 초점을 맞추어 전력시스템 성능을 시뮬레이션을 통해 검증하였다. 또한, 본 연구의 설계분야에서도 운전 및 유지·보수의 향상시키기 위해 FLNG 설비의 전력시스템을 분석하였다. The field of power system harmonics has been receiving a great deal of attention recently. This is primarily due to the fact that non-linear (or harmonic-producing) loads comprise an ever-increasing portion of what is handled at a typical industrial plant. The incidence rate of harmonic-related problems is low, but awareness of harmonic issues can still help increase offshore power plant system reliability. On the rare occasion that harmonics become a problem, this is either due to the magnitude of harmonics produced or power system resonance. This harmonic study used an electrical configuration for the offloading scenario of a Floating LNG (FLNG) unit, considering power load. This electrical network configuration is visible in the electrical network load flow study part of the project. This study has been carried out to evaluate the performance of an electric power system, focusing on the harmonic efficiency of an electrically driven motor system to ensure offshore plant safety. In addition, the design part of this study analyzed the electric power system of an FLNG unit to improve the safety of operation and maintenance.

AC TO AC Direct Voltage Conversion Using A Solid State Transformer

Um, Keehong The Institute of Internet 2013 International Journal of Internet, Broadcasting an Vol.5 No.1

In this paper, we present an intelligent digital controller circuit which can be applied to automatic voltage regulation. The proposed solid state transformer with Pspice simulation model shows that our approach is very efficient and produces the desirable output. It is comparable to an ordinary magnetic coupled autotransformer.

AC TO AC Direct Voltage Conversion Using A Solid State Transformer

Keehong Um 한국인터넷방송통신학회 2013 International Journal of Internet, Broadcasting an Vol.5 No.1