울트라커패시터를 이용한 UPS의 순시전압보상에 관한 연구

김춘삼,김지헌,김수홍,성원기,Kim, Choon-Sam,Kim, Ji-Heon,Kim, Soo-Hong,Sung, Won-Ki 한국조명전기설비학회 2006 조명·전기설비학회논문지 Vol.20 No.5

본 논문은 순간전압강하 보상을 위해 축전지와 울트라커패시터가 병렬로 연결된 무정전 전원장치 시스템을 제안하였다. 축전지와 병렬로 연결된 울트라커패시터는 정전시 순간전압강하를 보상하고, 출력전압의 전압 변동률을 감소시키는 역할을 한다. 무정전 전원장치에서 울트라커패시터의 빠른 순간전압보상 구현을 위해 3[kVA]의 시스템을 제작하여 실험을 수행하였다. 실험결과를 통하여 울트라커패시터의 빠른 보상특성과 울트라커패시터를 사용함으로써 출력전압의 변동률이 5[%]이내를 만족함을 확인하였다. This paper proposed UPS system parallel connected in battery and ultracapacitor to compensate instantaneous voltage drop. Ultracapacitor parallel connected with battery compensate instantaneous voltage drop at failure and it's reduced the voltage regulation of output voltage. We are produced for fast instantaneous voltage drop compensation of ultracapacitor at UPS system and experiments are achieved. Experimental result was verified that the ultracapacitor indicated the fast compensation characteristics and regulation of the output voltage satisfied within 5[%] by using ultracapacitor.

능동 스너버를 갖는 ZVT PWM AC-DC 승압 컨버터

金春杉(Choon-Sam Kim),成源基(Won-Ki Sung),李廷紋(Jung-Moon Lee),崔燦石(Chan-Sok Choi),金洙弘(Soo-Hong Kim) 대한전기학회 2008 전기학회논문지 Vol.57 No.2

Most of converter system could obtain almost unity power factor and make input current sinusoidal waveform, but they have many problems, such as electromagnetic interference and switching losses caused by switching noise in main switch. To solve these problems in hard switching PFC converter, soft switching converter using a resonant between capacitor and inductor is invented In this paper, advantages and disadvantages of conventional ZVT(Zero-Voltage-Transition) soft switching converter using a auxiliary resonant circuit is discussed. Then Improved ZVT soft switching converter proposed. This improved ZVT converter's operation principal, specific property, design scheme of main are described. From Simulation and experiment results of conventional ZVT soft switching and improved ZVT soft switching converter with active snubber, characteristics of the converter are confirmed.

고역률 고효율 승압형 AC-DC 컨버터

곽동걸,김춘삼,박하용,심재선,심상흥,Kwak, Dong-Kurl,Kim, Choon-Sam,Park, Ha-Yong,Shim, Jae-Sun,Shim, Sang-Heung 한국조명전기설비학회 2005 조명·전기설비학회논문지 Vol.19 No.7

본 논문은 전류불연속 제어에 의한 고역률, 고효율로 동작되는 승압형 AC-DC 컨버터에 대해 연구된다. 전류불 연속 제어 컨버터는 제어회로 구성이 간단하고 구성소자의 수를 줄일 수 있는 장점을 가진다. 제안된 컨버터의 입력전류는 듀티율 일정제어에 의한 교류 입력전압의 크기에 비례된 불연속적인 정현파 형태로 된다. 그 결과 입력역률은 거의 단위역률로 주어지며 듀티율 일정제어에 의해 제어기법이 간단하다. 또한 제안된 컨버터의 스위칭 소자들은 부분공진 기법에 의해 소프트 스위칭 동작으로 되어 스위칭 손실이 매우 낮으며 컨버터의 효율을 증대시킨다. 부분공진 회로부는 승압용으로 사용된 인덕터와 무손실 스너버 커패시터에 의해 설계되어 컨버터의 회로 토폴로지가 간단하다. 제안된 컨버터는 컴퓨터 시뮬레이션과 실험결과에 의해 그 타당성이 입증된다. This paper is studied on boost AC-DC converter of high power factor and high efficiency for discontinuous current control. The converter operated in discontinuous current control eliminates the complicated circuit control requirement, and reduces a number of components. The input current waveform in proposed circuit is got to be a discontinuous sinusoidal form in proportion to magnitude of ac input voltage under the constant duty cycle switching. Therefore, the input power factor is nearly unity and the control circuit is simple. Also the switching devices in a proposed circuit are operated with soft switching by the partial resonant method. The result is that the switching loss is very low and the efficiency of system is high. The partial resonant circuit makes use of a inductor using step up and loss-less snubber capacitor. The circuit topology of the converter is simplified. Some simulative results on computer and experimental results are included to confirm the validity of the analytical results.

전류불연속 제어의 새로운 PFC 스텝-업 AC-DC 컨버터

곽동걸(Dong-Kurl Kwak),김춘삼(Choon-Sam Kim),김천식(Chun-Sik Kim),이현우(Hyun-Woo Lee) 전력전자학회 2005 전력전자학술대회 논문집 Vol.- No.-

This paper is studied on a novel step-up AC-DC converter of power factor correction (PFC) by discontinuous current control. The converter operated in discontinuous current control eliminates the complicated circuit control requirement, and reduces a number of components. The input current waveform in proposed circuit is got to be discontinuous sinusoidal form in proportion to magnitude of ac input voltage under the constant duty cycle switching. Therefore, the input power factor is nearly unity and the control circuit is simple. Also the switching devices in a proposed circuit are operated with soft switching by the partial resonant method. The result is that the switching loss is very low and the efficiency of system is high. The partial resonant circuit makes use of a inductor using step up and loss-less snubber capacitor. The circuit topology of the converter is simplified. Some simulative results on computer and experimental results are included to confirm the validity of the analytical results.

전류불연속 제어의 고효율 부스트 DC-DC 컨버터에 관한 연구

郭東杰(Dong-Kurl Kwak),金春衫(Choon-Sam Kim) 대한전기학회 2005 전기학회논문지 B Vol.54 No.9

새로운 고효율 절연형 DC-DC 초퍼에 관한 연구

곽동걸(Dong-Kurl Kwak),김춘삼(Choon-Sam Kim),김수광(Soo-Kwang Kim) 대한전자공학회 2007 대한전자공학회 학술대회 Vol.2007 No.7

This paper is proposed to a novel DC-DC chopper of high efficiency. The general converters of high efficiency are made that the power loss of the used switching devices is minimized. To achieve high efficiency system, the proposed chopper is constructed by using a partial resonant circuit. The control switches using in the chopper are operated with soft switching for a partial resonant method. The control switches are operated without increasing their voltage and current stresses by the soft switching technology. The result is that the switching loss is very low and the efficiency of chopper is high. And the proposed chopper is added in a electric isolation. When the power conversion system is required to electric isolation, the proposed chopper is adopted with system development of high efficiency. The soft switching operation and the system efficiency of the proposed chopper is verified by digital simulation and experimental results.

비접촉 전원공급 시 2차측 코일 제작을 줄이기 위한 2차측 정류부 효율 개선에 관한 연구

유주희(Yu, Joo-Hee),김춘삼(Kim, Choon-Sam),성원기(Sung, Won-Ki) 한국산학기술학회 2011 한국산학기술학회논문지 Vol.12 No.3

본 논문은 코일 제작 시 고려사항인 1, 2차측 코일 인덕턴스, 턴수, 크기, 두께, 차폐지 등을 고려하여 리쯔 와이어로 나선형 코일을 제작하는데 이때 반자동화 권선기를 사용하게 된다. 1, 2차측 코일 사양을 정하여 코일을 제 작할 때 다양한 사양의 리쯔 와이어와 나선형 코일을 필요로 하게 되는데, 이때 제작 비용, 기간, 제작 시 발생하는 불량 등으로 인해 코일 샘플 제작에 어려움이 발생하고 원하는 사양의 코일 품질 관리에도 어려움이 생기게 된다. 이 를 개선하기 위해 2차측의 정류부를 개선함으로써 코일 설계 및 제작 시 다양한 코일 제작 사양의 범위를 좀더 포괄 적으로 할 수 있으며 제작 시 발생하는 비용을 줄이고, 기간 단축 및 코일의 품질 관리를 개선하고자 한다. The Spiral coil is made considering primary, secondary side coil inductance, turn number, size, thickness, and shielding area with the litz wire-type in case of manufacturing a coil, and at this time, the semi-automation winding machine is used. When deciding on primary and secondary side coil specification and manufacturing a coil, the spiral coil of a specification varied in the various litz wire of a specification is required, and at this time, a difficulty is generated by the manufacture cost, period which during, and failure the manufacture is generated in the coil sample making. A difficulty is in the desired coil quality control of a specification. Since improving the rectifier of the secondary side in order to improve this kind of problem, the range of the coil design and the during the manufacture, various coil manufacture specifications can be comprehensively made.

새로운 소프트 스위칭형 PFC 스텝 업-다운 초퍼에 관한 연구

곽동걸(Dong-Kurl Kwak),김춘삼(Choon-Sam Kim),심재선(Jae-Sun Shim),김종민(Jong-Min Kim) 전력전자학회 2006 전력전자학술대회 논문집 Vol.- No.-

In this paper, authors propose a novel power factor correction (PFC) step up-down chopper by soft switching. The proposed chopper for a discontinuous conduction mode (DCM) eliminates the complicated circuit control requirement and reduces the size of components. The input current wavform in the proposed chopper is got to be a sinusoidal form of discontinuous pulse in proportion to magnitude of ac input voltage under the constant duty cycle switching. Therefore, the input power factor is nearly unity and the control method is simple. To achieve a soft switching (ZCS and ZVS) of the proposed chopper is constructed by using a new loss-less snubber which is operated with a partial resonant circuit. The result is that the switching loss is very low and the efficiency of converter is high. Some simulative results on computer and experimental results are included to confirm the validity of the analytical results.

DSP에 의한 약계자영역 연구자석 동기전동기의 개선된 운전특성

尹炳道(Byung-Do Yoon),金春杉(Choon-Sam Kim),李炳松(Byung-Song Lee),金燦起(Chan-Ki Kim) 대한전기학회 1996 전기학회논문지 Vol.45 No.1

고역률 절연형 DCM 벅-부스트 컨버터에 관한 연구

곽동걸(Dong-Kurl Kwak),김춘삼(Choon-Sam Kim),유주희(Joo-Hee Yu),양기철(Ki-Chul Yang) 대한전기학회 2010 대한전기학회 학술대회 논문집 Vol.2010 No.4

This paper presents a novel isolated buck-boost converter for high power factor and high efficiency. The switching devices in the proposed converter are operated by soft switching technique using a new resonant circuit, and are driven with discontinuous conduction mode (DCM) according to pulse width modulation. The resonant circuit makes use of a step up-down inductor and a loss-less snubber capacitor. The input ac current waveform in the proposed converter also becomes a quasi sinusoidal waveform in proportion to the magnitude of input ac voltage under constant switching frequency. As a result, the proposed converter make it possible that the switching power losses are low, the efficiency of the converter is high, and the input power factor is nearly unity.