• 제목/요약/키워드: inverter system.

검색결과 2,793건 처리시간 0.024초

부분 공진형 소프트 스위칭 PWM DC-DC 고전압 컨버터 (Soft-Switched PWM DC-DC High-Power Converter with Quasi Resonant-Poles and Parasitic Reactive Resonant Components of High-Voltage Transformer)

  • 김용주;신대철
    • 전력전자학회논문지
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    • 제4권4호
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    • pp.384-394
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    • 1999
  • This paper deals with a fixed frequency full-bridge inverter type DC-DC high-power converter with high frequency high voltage(HFHV) transformer-coupled stage, which operates under quasi-resonant ZVS transition priciple in spite of a wide PWM-based voltage regulation processing and largely-changed load conditions. This multi-resonant(MR) converter topology is composed of a series capacitor-connected parallel resonant tank which makes the most of parasitic circuit reactive components of HFHV transformer and two additional quasi-resonant pole circuits incorporated into the bridge legs. The soft-switching operation and practical efficacy of this new converter circuit using the latest IGBTs are actually ascertained through 50kV trially-produced converter system operating using 20kHz/30kHz high voltage(HV) transformers which is applied for driving the diagnostic HV X-ray tube load in medical equipments. It is proved from a practical point of view that the switching losses of IGBTs and their electrical dynamic stresses relating to EMI noise can be considerably reduced under a high frequency(HF) switching-based phase-shift PWM control process for a load setting requirements.

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ACM에 의한 태양광 발전의 최대전력점 추적 알고리즘 개발 (Maximum Power Point Tracking Algorithm Development of Photovoltaic by ACM(Approximation Control Method))

  • 고재섭;최정식;정철호;정병진;김도연;정동화
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 심포지엄 논문집 정보 및 제어부문
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    • pp.215-216
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    • 2008
  • This paper is proposed a approximation control method(ACM) for the maximum power of a photovoltaic system. It is designed for power systems application and utilities. The proposed Maximum Power Point Tracking(MPPT) control has the advantage to provide a new simple way to approximate the optimal or rated voltage, the optimal or rated current and maximum power rating produced by a solar panel and the photovoltaic inverter. And this straightforward method has the advantage that Pmax and $V_{op}$ can be approximated using the same variable as the dynamic model without using complicate approximations or Taylor series. This paper is proposed MPPT using AMC using weather condition of domestic moderate program technique. This paper is proposed the experimental results to verify the effectiveness of the new methods.

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LLC 공진형 컨버터를 이용한 무정전전원장치 Battery Discharger 설계 (LLC Resonant Converter design for Uninterruptible Power Supply Battery Discharger)

  • 유광민;김승주;김경동;박승희;변용섭;임승범;이준영
    • 전력전자학회논문지
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    • 제18권3호
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    • pp.240-246
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    • 2013
  • An Uninterruptible Power Supply(UPS) is a system designed to deliver energy during accidents that the AC mains is out of its acceptable limits, without interruption of power flow through the load. Battery Discharger is the device to supply high quality power to the Inverter, when accidents occur, such as Power Failure. The Battery Discharger should have a fast response characteristics. The LLC resonant converter for UPS battery discharger is proposed. The proposed Battery Discharger offers substantial improvements in efficiency, size and cost. The proposed Battery Discharger of UPS approach is a good solution for high power applications above KW. To verify the validity of proposed Battery Discharger, simulations and experiments are carried out.

Design of a High-Voltage Piezoelectric Converter for Airbag Ignition Modules

  • Xiao, Hongbing;Du, Yu;Bai, Chunyu;Guo, Zerong;Yen, Kang K.
    • Journal of Power Electronics
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    • 제14권1호
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    • pp.183-193
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    • 2014
  • Due to the requirements for high reliability and accuracy, safety issues for airbag ignition systems need to be studied. In this paper, a high-voltage piezoelectric converter is designed to improve these requirements in airbag ignition systems. The proposed converter includes an inverter drive circuit, a Rosen piezoelectric transformer (PZT), an output circuit and a feedback control circuit. The key components of the high-voltage piezoelectric transformer are analyzed in detail. In addition, the proposed converter system is simulated and implemented for testing. The experimental results show that when the power supply is turned on, the charging time is less than 800ms. Furthermore, the output voltage of this converter can be kept between 2.9kV and 3.1kV, under high-efficiency constant current charging mode and zero-voltage switching conditions.

BF 컨버터의 역률 개선에 관한 연구 (A study on the power factor improvement of the Boost Forward Converter)

  • 임승하
    • 전자공학회논문지T
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    • 제36T권3호
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    • pp.56-63
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    • 1999
  • 본 논문에서는 BF 컨버터의 Active PFC 시스템을 구성하고, 전력 변환시 입력 전류를 전원 전압과 동상인 정현파로 제어하며 직류 출력 전압을 제어하기 위한 PWM-PFM 제어 기법을 사용하여 역률을 개선하였다. FET와 IGBT를 이용하여 본 논문에서 제시한 Boost 컨버터와 인버터 회로를 구성하였고, 제안된 Boost 컨버터의 제어 회로는 마이크로프로세서 80C196으로 구성하였다. 또한 입력 전압이 30V이고, Boost 인덕터가 1.1 mH일 때 정격 출력은 전압 50V, 전류 IA, 듀티비 (Duty Ratio) 0.5 이상으로 하였다. 부하 저항의 변화에 따른 전압 변화를 PWM-PFM 제어 기법을 이용하여 제어하였고, 전류 성형 기법을 이용하여 역률이 0.96 가지 개선됨을 실험으로써 입증하였다.

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Modeling and Control Design of Dynamic Voltage Restorer in Microgrids Based on a Novel Composite Controller

  • Huang, Yonghong;Xu, Junjun;Sun, Yukun;Huang, Yuxiang
    • Journal of Electrical Engineering and Technology
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    • 제11권6호
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    • pp.1645-1655
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    • 2016
  • A Dynamic Voltage Restorer (DVR) model is proposed to eliminate the short-term voltage disturbances that occur in the grid-connected mode, the switching between grid-connected mode and the stand-alone mode of a Microgrid. The proposed DVR structure is based on a conventional cascaded H-bridge multilevel inverter (MLI) topology; a novel composite control strategy is presented, which could ensure the compensation ability of voltage sag by the DVR. Moreover, the compensation to specified order of harmonic is added to implement effects that zero-steady error compensation to harmonic voltage in specified order of the presented control strategy; utilizing wind turbines-batteries units as DC energy storage components in the Microgrid, the operation cost of the DVR is reduced. When the Microgrid operates under stand-alone mode, the DVR can operate on microsource mode, which could ease the power supply from the main grid (distribution network) and consequently be favorable for energy saving and emission reduction. Simulation results validate the robustness and effective of the proposed DVR system.

A Novel Filtering Method Based on a Nonlinear Tracking Differentiator for the Speed Measurement of Direct-drive Permanent Magnet Traction Machines

  • Wang, Gaolin;Wang, Bowen;Zhao, Nannan;Xu, Dianguo
    • Journal of Power Electronics
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    • 제17권2호
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    • pp.358-367
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    • 2017
  • This paper presents a novel filtering method for speed measurements to improve the low-speed performance of the direct-drive permanent magnet traction machines for elevators. Based on the theory of nonlinear tracking differentiator (NTD), this method, which can act as a high performance filter of a raw speed signal, obtains a more accurate speed feedback signal when applying a low-resolution encoder. In addition, it can relieve the interference caused by the position derivative for speed sampling. By analyzing the frequency response of the NTD, the influence of its parameters on the performance of the speed filtering is investigated. Compared with different types of low-pass filters, the proposed method shows a shorter time delay and a stronger ability in terms of noise suppression when the parameters are selected carefully. In addition, when using the measured speed signal through a nonlinear tracking differentiator as the feedback of the system, the motor runs more steadily at low speeds. As a result, the riding comfort of a direct-drive elevator can be improved. The feasibility of the proposed strategy was verified on an 11.7kW elevator traction machine using a commercial inverter.

액티브 스너버를 이용한 고주파 용접기 컨버터 개발 (Development of Converter for High Frequency Welding Machines using Active Snubber)

  • 신준영;이재민;최승원;이준영
    • 전력전자학회논문지
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    • 제21권4호
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    • pp.351-355
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    • 2016
  • Welding machines are high-capacity systems used in a low-frequency range using IGBT. As their system is similar to a large transformer, most welding machines suffer a great loss because of hard switching and vast leakage inductance. A voltage-balancing circuit is designed to overcome these shortcomings. This circuit can reduce the transformer size by making it into a high frequency and reducing the input voltage by half and by adopting a serial structure that connects two full-bridges in a series to use a MOSFET with a good property at high frequency. In addition, a Schottky diode is used in the primary rectifier to overcome the low efficiency of most welding machines. To use the Schottky diode with a reliably relatively low withstanding voltage, an active snubber is adopted to effectively limit the ringing voltage of the diode cut-off voltage.

혼합수소발생기용 전력변환장치의 특성 (Characteristic of Hydrogen-oxygen Mixed Gas Power Conversion System)

  • 문상필;이해수;정장근;김창일;조길제;김상돈
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2007년도 추계학술대회 논문집
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    • pp.323-326
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    • 2007
  • In this paper, the basic experiment, electrolytic cell design and basic manufacturing have been made to interpret the characteristics of Hydrogen-Oxygen-Gas-Generator. As for the detailed matters, the data research on basic technology on Hydrogen-Oxygen-Gas and analysis on characteristics of Hydrogen-Oxygen-Gas from basic experiment. Also the experiment of characteristics and comparative evaluation between constant current source using SCR converter from existing method and constant current source using new phase shift PWM control method converter. As results when it has injected constant DC current, we has compared Gas quantities by variable ripple frequencies using phase shift PWM control method converter. Therefore, in linear region, it has not different Gas quantities by constant DC current and by phase shift PWM control method converter. Also, it has increased Gas quantities wilder linear region when put ripple frequency at saturation region. Through, Gas quantities and input rower, it has acquired higher input power per Gas quantities at put pulse current. Therefore, when designing converter or inverter for electrolysis, which has ripple current.

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ALM-FNN 제어기에 의한 SynRM 드라이브의 최대토크 제어 (Maximum Torque Control of SynRM Drive with ALM-FNN Controller)

  • 고재섭;최정식;이정호;김종관;박기태;박병상;정동화
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.155-157
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    • 2006
  • The paper is proposed maximum torque control of SynRM drive using adaptive learning mechanism-fuzzy neural network(ALM-FNN) controller and artificial neural network(ANN). The control method is applicable over the entire speed range and considered the limits of the inverter's current and voltage rated value. For each control mode, a condition that determines the optimal d-axis current $i_d$ for maximum torque operation is derived. The proposed control algorithm is applied to SynRM drive system controlled ALM-FNN and ANN controller, the operating characteristics controlled by maximum torque control are examined in detail. Also, this paper is proposed the analysis results to verify the effectiveness of the ALM-FNN and ANN controller.

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