• 전력전자학회논문지
• /
• 제11권3호
• /
• pp.193-200
• /
• 2006

본 논문에서는 효율을 개선하고 인버터 스위칭 주파수를 줄이기 위하여 벅-부스트 형식을 기반의 PWM 전류형 인버터를 내장한 6-pulse-shift 컨버터 구조를 제안한다. 이는 에너지 저장장치 없이 태양광 시스템과 전력계통 사이를 연계하는 시스템으로 사용할 수 있다. 제안된 회로는 초퍼로 동작하는 6개의 전류형 벅-부스트 컨버터와 교류 출력의 극성을 결정하는 한 개의 전파 브리지 인버터로 구성된다. 따라서 제안된 인버터는 스위칭 손실을 줄이고 단위 역률운전을 구현하는 장점을 갖는다. 본 논문에서 이론적인 배경을 논하고 TMS320F2812를 사용하여 구현된 인버터 시작품에 대한 입출력 특성을 실험적으로 입증하였다.

• 전력전자학회논문지
• /
• 제3권4호
• /
• pp.323-329
• /
• 1998

계통연계형 태양광발전시스템을 PWM 쵸퍼와 전류형 인버터로 구성하였다. 전류형 인버터의 직류리액터를 경감하는 방법으로, 직류측에 병렬공진회로를 삽입함에 따라 맥동전력의 일부를 교류 전해콘덴서에 축적하여 직류전류의 맥동을 억제하는 방법과, 쵸퍼의 변조파를 전원주파수의 2배로 제어하여 직류전류의 맥동을 억제하는 것을 비교 검토하였다. 그리고 태양전지전류와 쵸퍼의 변조율만을 이용하여 태양전지가 항상 최대출력점에서 동작하도록 하였다. 계통과 연계함으로서 출력전력이 부하전력보다 큰 경우에는 잉영전력을 계통전원에 공급하고, 발전전력 부하전력에 대해 부족한 경우에는 계통전원이 부족분을 공급하는 것을 확인하였다.

• 전기학회논문지
• /
• 제67권12호
• /
• pp.1602-1610
• /
• 2018

Induction heating can convert electrical energy to thermal energy with high conversion efficiency and quick heating. Currently, a current source rectifier/inverter-fed parallel resonant circuit is widely used as an induction heating power supply for forging applications. However, the conventional induction heating power supplies composed of phase-controlled rectifier and SCR inverter have low efficiency and low power factor at input side, and require additional starting circuitry. So this paper proposes new induction heating power supply topologies for forging applications which have high power factor, high efficiency, and large output power. It also suggests detailed design guideline.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 제38회 하계학술대회
• /
• pp.1222-1223
• /
• 2007

This paper suggests a 6-pulse-shift converter with PWM current-source inverter based on buck-boost configuration to improve the efficiency and to reduce the switching frequency of inverter for photovoltaic generation system, the device can be operated as interface system between solar module system and power system grid without energy storage cell. the circuit has six current-source buck-boost converter which operate chopper part has one full bridge inverter which make a decision the polarity of AC output. Therefore, the proposed PWM power inverter has advantages such as the reduction of witching loss and realization of unity power factor operation. the theoretical backgrounds are discussed and the input-output characteristics for the implemented prototype inverter using TMS320F2812 are verified experimentally in this paper.

• Journal of Power Electronics
• /
• 제14권2호
• /
• pp.302-314
• /
• 2014

Due to advancements in power electronics and inverter topologies, the current controlled multilevel voltage-source pulse width modulated (PWM) inverter is usually preferred for accurate control, quick response and high dynamic performance. A multilevel topology approach is found to be best suited for overcoming many problems arising from the use of high power converters. This paper presents a comprehensive review and comparative study of several current control (CC) techniques for multilevel inverters with a special emphasis on various approaches of the hysteresis current controller. Since the hysteresis CC technique poses a problem of variable switching frequency, a ramp-comparator controller and a predictive controller to attain constant switching frequency are described along with its quantitative comparison. Furthermore, various methods have been reviewed to achieve hysteresis current control PWM with constant switching frequency operation. This paper complies various guidelines to choose a particular method suitable for application at a given power level, switching frequency and dynamic response.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
• /
• pp.507-510
• /
• 2003

This paper presents a novel prototype of tile three-phase bridge power block module type a auxiliary resonant AC link snubber circuit, which is effectively used for the three-phase voltage source type sinewave soft switching PWM inverter using IGBTs. Its operating principle Is described for current source load model, along with its practical design approach based on the simulation data. The performance evaluation of the three-phase voltage source type snewave soft switching PWM inverter incorporating a single three-phase bridge mo여le of active auxiliary resonant AC link snubber treated here Is illustrated, which is concerned with power duality efficiency power loss analysis. This inverter is discussed as compared with those of tile three-phase voltage source type sinewave hard switching PWM inverter. The power loss analysis of this soft switching PWM Inverter using IGBT power modules is evaluated on the basis of the measured v-i characteristics and switching power losses of IGBT, and antiparaliel diodes. The practical effectiveness of this inverter is proven by the power loss analysis for distributed power supply.

• 한국통신학회논문지
• /
• 제15권5호
• /
• pp.384-398
• /
• 1990

本 硏究는 電壓源 인버어터의 펄스信號를 發生시키기 위한 PWM 方式의 特性 및 長短點을 比較하여 提示하였다. 電壓源 인버어터를 PTR로 設計하여 VSD을 構成한 후 各 PWM 方式으로 誘導電動機를 可變速 運轉시켜 騷音레벨, 線間電壓 및 電流 波形, 電流 高周波 스펙트럼을 測定하였다. 그 結果, Suboptimal PWM 方式은 高周波 影響이 Optimal PWM 方式과 類似한 結果로 良好하게 나타나며 microprocessor 應用이 可能하였고, TP PWM 方式은 3相中 2相만 制御하기 때문에 CPO에 要하는 處理負擔을 줄일 수 있으며 出力電壓을 擴大시킬 수 있는 優秀한 方式임을 알 수 있었다.

• Journal of Power Electronics
• /
• 제3권4호
• /
• pp.239-248
• /
• 2003

This paper presents a novel prototype of three-phase voltage source type zero voltage soft-switching inverter with the auxiliary resonant snubbers suitable for high-power applications with IGBT power module packages in order to reduce their switching power losses as well as electromagnetic conductive and radiative noises. A proposed single inductor-assisted resonant AC link snubber circuit topology as one of some auxiliary resonant commutation snubbers developed previously to achieve the zero voltage soft-switching (ZVS) for the three-phase voltage source type sinewave PWM inverter operating under the instantaneous space voltage vector modulation is originally demonstrated as compared with the other types of resonant AC link snubber circuit topologies. In addition to this, its operation principle and unique features are described in this paper. Furthermore, the practical basic operating performances of the new conceptual instantaneous space voltage vector modulation resonant AC link snubber-assisted three-phase voltage source type soft-switching PWM inverter using IGBT power module packages are evaluated and discussed on the basis of switching voltage and current waveforms, output line to line voltage quality, power loss analysis, actual power conversion efficiency and electromagnetic conductive and radiative noises from an experimental point of view, comparing with those of conventional three-phase voltage source hard-switching PWM inverter using IGBT power modules.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 1996년도 창립기념 전력전자학술발표회 논문집
• /
• pp.109-112
• /
• 1996

In this paper, we composed utility interactive photovoltaic generation system of current source inverter, and controlled that low harmonic and high power factor are hold by supposing control and compensation method which is concerned with synchronous signal distortion and modulation delay. And we put parallel resonant circuit into dc link, so, magnitude of direct reactance was reduce by restraining direct current pulsation which had accumulation of pulsating power in alternating electrolytic condenser. Also we controlled that modulation factor is operated around maximum output of solar cell.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
• /
• pp.524-528
• /
• 1998

The voltage-source inverters are normally equipped with an electrolytic capacitor in their DC link, however, the electrolytic capacitor has several disadvantages such as increasing size, limiting converter life and reliability. Therefore, several approaches for removing the DC link capacitor have been studied by the authors. This paper proposes a new voltage-source inverter without DC link components. To reduce waveform distortion of the AC source current, the current-controlled PWM-rectifier with di/dt feedback is introduced. The di/dt feedback gain and LC parameters are investigated by calculation for a 0.75kW induction motor driven by this inverter. The calculated AC source currents maintain nearly sinusoidal waveforms with a unity power factor.