• 제목/요약/키워드: tight regulation

검색결과 88건 처리시간 0.025초

The study of the Asymmetrical Half-Bridge Converter With magnetic coupled post regulator

  • Hyeon, Byeong-Cheol;Cho, Bo-Hyung
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2007년도 추계학술대회 논문집
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    • pp.121-123
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    • 2007
  • In this paper, a multiple-output converter using a coupledinductor is proposed. The Asymmetrical Half-Bridge Converter (AHBC), which is used as a master converter, obtains ZVS in the primary side switches. For the tight output voltage regulation of the slave output, the Secondary Side Post Regulator (SSPR) is adopted. The proposed magnetically coupled output filter inductor reduces the number of semi-conductor devices and magnetic components. Also, the circuit enables ZCS off switching in the SSPR MOSFET and rectifying diodes. The modes of operation which are caused by the coupled-inductor and post regulator are explained. The analyzed modes of operation of the proposed multiple-output converter are verified by the simulation and experimental results.

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Control of Acetate Production Rate in Escherichia coli by Regulating Expression of Single-Copy pta Using $lacI^Q$ in Multicopy Plasmid

  • Lee, Sun-Gu;Liao, James C
    • Journal of Microbiology and Biotechnology
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    • 제18권2호
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    • pp.334-337
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    • 2008
  • A tightly regulated gene expression system composed of a single-copy target gene under the control of a lac promoter derivative and lacI gene in a multicopy plasmid is proposed, and its ability to control the flux of a metabolic pathway is demonstrated. A model system to control the flux of acetyl-CoA to acetyl phosphate was constructed by integrating pta, a gene encoding phosphotransacetylase, under a tac promoter into the chromosome of E. coli with a pta-negative background and transforming a multicopy plasmid containing the $lacI^Q$ gene into the strain. The production rate of acetate was shown to be tightly controlled when varying the concentration of the inducer (IPTG) in he model system.

능동 클램프 모드로 동작하는 단일 전력 AC/DC 컨버터에 의한 역률개선 (Power Factor with Single Power Stage AC/DC Converter Operated in Active-Clamp Mode)

  • 윤신용;백수현;김용;김철진;어창진
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제50권8호
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    • pp.392-401
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    • 2001
  • This paper presents the single-stage high power factor AC to DC converter operated in active-clamp mode. The proposed converter is added active-clamping circuit to boost-flyback single-stage power factor corrected power supply. The active-clamping circuit limits voltage spikes, recycles the energy trapped in the leakage inductance, and provides a mechanism for achieving soft switching of the electronic switches to reduce the switching loss. The auxiliary switch of active-clamping circuit uses the same control and driver circuit as the main switch to reduce the additional cost and size. To verify the performance of the proposed converter, a 100W converter has been designed. The proposed converter gives good power factor correction, low line current harmonic distortions, and tight output voltage regulation, as used unity power factor.

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하이브리드 3레벨 다출력 DC-DC 컨버터 (Multi Output Hybrid Three level DC-DC Converter)

  • 강철하;이하석;주종성;;김은수;이승민;김광섭
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2014년도 추계학술대회 논문집
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    • pp.9-10
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    • 2014
  • 최근 신재생에너지 및 전기자동차, 통신 IT 서버 전원 및 가전기기 등의 발전에 따라 고 전력밀도(High Power Density), 고 응답(Fast Transient Response) 및 고정밀(Tight Regulation) 출력제어를 위한 다 출력 절연형 DC/DC 컨버터가 개발 및 연구되고 있다. 본 논문에서는 개별적인 정밀제어를 요구하는 다 출력 DC-DC 컨버터에 대한 내용으로 위상천이(Phase-shift) DC-DC 컨버터와 LLC 공진컨버터 제어개념을 하나의 주회로를 사용하여 위상천이제어(Phase-shifted Modulation, PM)와 가변주파수제어(Variable Frequency Modulation, FM)를 통해서 개별적으로 정밀 제어할 수 있는 하이브리드 다 출력 3레벨 DC-DC 컨버터에 관한 내용이다.

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FGF signaling: diverse roles during cochlear development

  • Ebeid, Michael;Huh, Sung-Ho
    • BMB Reports
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    • 제50권10호
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    • pp.487-495
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    • 2017
  • Mammalian inner ear comprises of six sensory organs; cochlea, utricle, saccule, and three semicircular canals. The cochlea contains sensory epithelium known as the organ of Corti which senses sound through mechanosensory hair cells. Mammalian inner ear undergoes series of morphogenesis during development beginning thickening of ectoderm nearby hindbrain. These events require tight regulation of multiple signaling cascades including FGF, Wnt, Notch and Bmp signaling. In this review, we will discuss the role of newly emerging signaling, FGF signaling, for its roles required for cochlear development.

A New Modular 3-phase AC-DC Flyback Converter for Telecommunication

  • Choi, J.Y.;Lee, J.P.;Choy, I.;Song, J.H.;Kim, T.Y.
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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    • pp.790-796
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    • 1998
  • A novel mode of parallel operation of a modular 3-phase AC-DC flyback converter for power factor correction along with tight regulation was recently analyzed and presented. The advantage of the proposed converter does not require expensive high voltage and high current devices that are normally needed in popular boost type 3-phase converter. In this paper the detailed small signal analysis of the modular 3-phase AC-DC flyback converter is provided for control purposes and also experimental results are included to confirm the validity of the analysis.

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Novel Modular 3-phase AC-DC Flyback Converter for Telecommunication

  • Park, Ju-Yeop;Lee, Jong-Pil;Kim, Taek-Yong;Song, Joong-Ho;Ick Choy
    • Journal of Power Electronics
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    • 제2권3호
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    • pp.212-219
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    • 2002
  • A novel mode of parallel operation of a modular 3-phase AC-DC flyback converter for power factor correction along with tight regulation was recently analyzed and presented. The advantage of the proposed converter does not require expensive high voltage and high current devices that are normally needed in popular boost type 3-phase converter. In this paper tile detailed small signal analysis of the modular 3-phase AC-DC flyback converter is provided for control purpose and also experimental results are included to confirm the validity of the analysis.

슬라이딩 모드 제어기를 사용한 계통연계형 태양광 발전시스템의 강인한 최대전력점 제어기 설계 (Robust maximum power point tracker using sliding mode controller for the single-stage grid-connected photovoltaic system)

  • 김일송;박진식;정신명;윤명중
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2005년도 전력전자학술대회 논문집
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    • pp.340-342
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    • 2005
  • A sliding mode controller for the grid-connected photovoltaic system has been presented. This controller is constructed from the time-varying sliding surface In order to control the sinusoidal inductor current and solar array power simultaneously. The proposed controller can achieve the tight regulation of current and power under the parameter variation environment.

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A Sliding Mode Control Design based on the Reaching Law for Matrix Rectifiers

  • Wang, Zhiping;Mao, Yunshou;Hu, Zhanhu;Xie, Yunxiang
    • Journal of Power Electronics
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    • 제16권3호
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    • pp.1122-1130
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    • 2016
  • This paper presents a novel approach for achieving both a tight DC voltage regulation and a power factor control by applying the Reaching Law Sliding Mode Control (RL-SMC) and the conventional Sliding Mode Control (SMC). Applying these strategies on a matrix rectifier (MR) can achieve a unity grid side power factor when the DC load changes widely and it can provide a ripple-free output voltage that is easily affected by distortions of the three-phase ac voltage supply. Furthermore, by employing the reaching law on the SMC can solve the chatting problem of the sliding motion. Comparative Matlab simulations and experimental verifications for these strategies have been presented and discussed in this paper. The results show that by applying the SMC and RL-SMC on a MR can achieve a unity grid side power factor and a regulated ripple-free DC output.

50kV 고전압 인버터 고정밀 출력설계에 관한 연구 (Study on the high precision output of 50kV high-voltage inverter)

  • 손윤규;서재학;오종석;조무현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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    • pp.2199-2201
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    • 2005
  • High voltage power supply with pulse load($4.5{\mu}s$ and PRF 60Hz) condition is investigated which is of interest for applications like Klystron modulator power supplies with output voltage of 50kV. The performance specifications with this type of power supplies are very stringent demanding tight regulation(<0.01%) and high efficiency(> 85%). The solution to this problem as a single stage converter is very difficult. The final output voltage is obtained as sum of the output of SCPS & PCPS. The combination of the two stages can satisfy the pulse load specifications. The analysis of the voltage and power division between SCPS & PCPS has been done for the proposed topology. It has studied under various operating conditions of line and load. Simulation results are validated by experimental results.

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