• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.220-226
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• 2010

In this paper, the static overmodulation is proposed for the 2-phase full bridge inverter. The overmodulation strategy increases a fundamental output voltage and improves a voltage utilization up to the maximum in the overmodulation range. The linear modulation range and static overmodulation range are defined in the 2-phase full bridge inverter. The overmodulation strategies which increase a voltage utilization until the 4-step mode by linearization of the output voltage in overmodulation range are proposed. To maintain a linearity of the relation between a reference voltage and a fundamental output voltage, this paper suggests a compensation voltage, whose magnitude or phase is modified to the proposed control scheme. Simulation and experimentation results demonstrate the effectiveness of the proposed algorithms.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.912-915
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• 1993

In this paper, the speed of single phase induction motor driven by full bridge inverter is controlled by a PID controller under condition of disturbance load and setpoint changes, and the current characteristics of the system is investigated to look for the good properties of A.C. motor torque through the results of experiment. From the experimental result, it is confirmed that the speed of single phase induction motor driven by full bridge series inverter can be smoothly controlled by an analog PID controller.

• 전력전자학회논문지
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• 제16권1호
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• pp.30-37
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• 2011

본 논문에서는 풀-브리지 인버터와 양방향 스위치를 가지는 5-레벨 인버터를 직렬 결합시켜 출력전압에 다수의 레벨을 형성할 수 있는 멀티레벨 인버터 구조를 제안한다. 제안된 회로의 입력전압원 크기가 서로 동일한 경우와 3의 배수 형태를 가지는 경우에 대한 특성을 분석하고 시뮬레이션 및 실험을 통해 효율적인 혼합형 회로 구성을 제시한다. 또한 기존의 변압기를 이용한 방식과 비교하여 장단점을 분석한다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2013년도 추계학술대회 논문집
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• pp.229-230
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• 2013

The conventional Three-Stage electronic ballast is stable, but Two-Stage electronic ballast has been researching because of efficiency. Three-Stage electronic ballast is consisted of PFC circuit, buck converter, and inverter circuit, but Two-stage is consisted of PFC circuit, Buck-Inverter full bridge circuit. The Buck-Inverter full bridge inverter consists of two half bridge inverters for low frequency switching, and high frequency switching. In the case of street lamp it is far from a lamp to a ballast, the conventional pulsed high voltage ignitor can not turn on the HID lamps because of reduction of ignition voltage. Therefore, it needs to do the research on a resonant ignition to turn on the HID lamps. Therefore, in the Two-Stage electronic ballast which has the resonant tank for ignition, the transient resonant current because of low frequency changing is analyzed, the novel algorithm is proposed to resuce the transient current.

• 조명전기설비학회논문지
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• 제28권1호
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• pp.1-8
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• 2014

The conventional Three-Stage electronic ballast is stable, but Two-Stage electronic ballast has been researching because of efficiency. Three-Stage electronic ballast is consisted of PFC circuit, buck converter, and inverter circuit, but Two-stage is consisted of PFC circuit, Buck-Inverter full bridge circuit. The Buck-Inverter full bridge inverter consists of two half bridge inverters for low frequency switching, and high frequency switching. In the case of street lamp it is far from a lamp to a ballast, the conventional pulsed high voltage ignitor can not turn on the HID lamps because of reduction of ignition voltage. Therefore, it needs to do the research on a resonant ignition to turn on the HID lamps. Therefore, in the Two-Stage electronic ballast which has the resonant tank for ignition, the transient resonant current because of low frequency changing is analyzed, the novel algorithm is proposed to resuce the transient current.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 춘계학술대회
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• pp.685-688
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• 2015

기존의 컨버터에서 널리 사용되는 위상천이 풀브리지 컨버터(Phase-Shifted Full-Bridge Converter) 경우 입력 전원 변화에 출력 전압의 변동이 있는 경우 듀티 변화에 따른 Freewheeling 구간이 존재하게 되며 효율을 감소시키는 요인이 된다. 본 논문에서는 고효율을 요구하는 ESS 시스템에서 컨버터/인버터의 효율 향상 방안을 제시한다. Freewheeling 구간에서 ZVS(Zero Voltage Switching) 실패문제를 해결하기 위한 듀티 제어 기법을 사용하여 구현하였으며 실험 결과 효율을 향상시켰다.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 학술대회 논문집
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• pp.377-382
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• 2005

This paper presents two new circuit topologies of DC bus lineside active edge resonant snubber assisted soft-switching PWM full-bridge DC-DC converter acceptable for either utility AC 200V-rms or AC 400V-rms input voltage source. One topology of proposed DC-DC converters is composed of a typical voltage source-fed full-bridge high frequency PWM inverter using DC busline side series power semiconductor switching devices with the aid of a parallel capacitive lossless snubber. All the active power switches in the full-bridge arms and DC busline can achieve ZCS turn-on and ZVS turn-off commutations and the total turn-off switching power losses of all active switches can be reduced for high-frequency switching action. It is proved that the more the switching frequency of full-bridge soft switching inverter increases, the more soft-switching PWM DC-DC converter with a hish frequency transformer link has remarkable advantages for its efficiency and power density as compared with the conventional hard-switching PWM inverter type DC-DC converter

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.238-242
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• 2004

The paper describes an automatic frequency control current-fed inverter for forging applications. The IGBT in series with diodes as its switching devices in the inverter circuit which is of full-bridge type. The operating frequency is automatically tracked to maintain a small constant leading phase angle when load parameters change. The load voltage is controlled to protect the switches. The output power can be adjusted by varying the input current from phase controlled rectifiers which is a part of current source. The system has been operated at 15-17 kHz. The output power transferred to the load is 1,595 watts. It can heat the steel work pieces with 15 mm diameter and 120 mm long from room temperature to approximately 1100 $^{\circ}C$ within 20 seconds with 0.97 leading power factor on the input side.

• 전기학회논문지
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• 제60권1호
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• pp.78-84
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• 2011

In this paper, the switching frequency and THD for the reduction instead of traditional single phase inverter using a new type of central arm of the single phase inverter is proposed. The proposed single phase inverter topology, the existing one to add a arm by two-way central switch 3-level output voltage can be raised and, central arm, especially one or two of the switches by using a switch to the diode current switching algorithm was simplified. During the dead time because of this, depending on the direction of the current level does not appear in any other existing level compared to the inverter output voltage level of the THD has the advantage that less can be. The simulation and experimental results verified the validity of the proposed topology.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.117-122
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• 2005

This paper proposes an inverter for the grid-connected photovoltaic system based on the transformer-less inverter. This system consists of a high frequency converter bridge, high frequency transformer, diode bridge rectifiers, a DC filter, a low frequency inverter bridge, and an AC filter. The high frequency converter bridge switching at 20kHz is used to generate bipolar PWM pulse, and the high frequency transformer raise its voltage twice, which is subsequently rectified by diode bridge rectifiers to result in a full-wave rectified sine wave. Finally, it is unfolded by a low frequency inverter bridge to result in a 60Hz sine wave power output. Even though the high frequency link system needs more power semiconductors, a reduced size, light weight, and saved parts cost make this system more comparative than the other systems due to elimination of 60Hz transformer.