• 전기학회논문지
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• 제60권8호
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• pp.1523-1528
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• 2011

This paper proposes buck-type charging method using motor inductance, 3-phase inverter and bi-directional converter without an additional charger in plug-in hybrid electric vehicles. The proposed system has advantages over the conventional system such as high charging efficiency, high power factor, and low total harmonic distortion. The validity of each methods are verified by theoretical analysis and simulation.

• Journal of Power Electronics
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• 제16권6호
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• pp.2284-2293
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• 2016

With the rapid development of clean energy, photovoltaic (PV) generation has been utilized in the harmonic compensation of power systems. This paper presents a novel multi-function PV micro-inverter with three stages (pseudo-two-stage). It can inject active power and compensate harmonic currents in the power grid at the same time. In order to keep the micro-inverter working under the maximum allowable output power, an optimized capacity limitation strategy is presented. Moreover, the harmonic compensation can be adjusted according to the customized requirements of power quality. Additionally, a phase shedding strategy in the DC/DC stage is introduced to improve the efficiency of parallel Boost converters in a wide range. Compared with existing capacity limitation methods, the proposed strategy shows better performance and energy efficiency. Simulations and experiments verify the feasibility of the micro-inverter and the effectiveness of the strategy.

• 전력전자학회논문지
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• 제10권2호
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• pp.130-137
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• 2005

LCD는 광변조기능을 가지는 수광 소자로서 발광원인 백라이트를 필요로 하는데 일반적으로 냉음극 방전램프(CCFL: Cold Cathode Fluorescent Lamp)가 사용된다. 기존의 권선형 변압기를 이용한 인버터를 구성하여 멀티램프를 구동하고 있지만 이는 코어나 권선 손실에 의한 효율 저하와 부피나 중량의 증가, 그리고 과열에 의한 화재의 위험성을 가지고 있다. 이러한 문제들을 해결하기 위해 본 논문에서는 압전 변압기를 이용한 멀티램프 구동용 인버터를 설계 지침에 따라 구성하였다. 인버터 하나로 압전 변압기를 병렬로 연결하는 방식을 이용하였고, 또한 전류 부담이 적은 외관 전극 형광 램프(EEFL: External Electrode Fluorescent Lamp)를 이용한 멀티램프 구동 방법이 압전 인버터에 적용 가능한지를 확인하였다.

• 대한방사선기술학회지:방사선기술과학
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• 제31권2호
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• pp.123-127
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• 2008

목 적: 임상에서 인버터식 X선장치의 사용이 보편화됨에 따라 이에 대한 보다 정확하고 간편한 성능평가 방법이 요구되고 있다. 따라서 최근 국내에 소개되어 사용되고 있는 X-Ray Multi-Function Test Device (model : Xi (unfors)-prestige)를 이용한 성능평가의 유용성을 확인하고자 한다. 방 법: 인버터식 X선장치의 성능 평가시 접속형 측정장비로 널리 활용되고 있는 Dynalyzer III를 이용한 성능평가를 기준으로 하여 비접속형 측정장비인 X-Ray Multi-Function Test Device (model: Xi (unfors)-prestige)의 성능평가를 비교 분석하여 그 유용성을 검토하였다. 결 과: 두 측정기에 대한 X선 출력선량은 큰 차이 없이 측정되었으며 촬영조건 등의 변화에 따라서 접속형인 Dynalyzer III가 약간 증가된 값으로 측정되었으며 출력의 재현성은 두 측정기 모두 성능평가 합격 기준 0.05 이하인 0.002 이하로, 직선성은 합격기준인 0.1 이하로 평가되었다. 촬영조건의 정확도에서는 관전압은 1.8과 2, 관전류는 2.01과 2.3, 촬영시간은 T > 0.01 sec에서 ${\pm}10%$ 이하로 나타났다. 모두 성능평가 기준의 허용범위에 있는 것으로 나타났다. 결 론: X-Ray Multi-Function Test Device (model: Xi (unfors)-prestige) 측정기를 이용한 인버터식 X선장치의 X선 출력의 재현성, 직선성과 촬영조건의 정확도에 대한 성능평가의 유용성을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1676_1677
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• 2009

This paper uses the softstarter function of the inverter in the place of business where the flow control is possible, multi maneuver method as the application (with 1 inverter various pump maneuver/standstill which is soft) box the plan which prevents the small hand of the equipment which is caused by maneuver electric current presented.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제3B권2호
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• pp.103-110
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• 2003

With significant development of power electronics technology, the proliferation of nonlinear loads such as static power converters has deteriorated power quality in power transmission and distribution systems. Notably, voltage harmonics resulting from current harmonics produced by the nonlinear loads have become a serious problem in many countries. Many photovoltaic power generation systems installed in building systems have harmonics that are the worst object for distribution systems as a utility interactive system, and it tends to spread out continuously. Proposed and implemented in this paper is a multi-function inverter control strategy that allows a shunt active filter function to the power inverter of the photovoltaic power generation system established on a building system. The effectiveness of the proposed system is demonstrated through the simulation of a hypothetical power system using PSCAD/EMTDC.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 추계종합학술대회 B
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• pp.195-198
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• 2008

최근 태양광 발전시스템 등 낮은 전압을 발생하는 전원소스를 이용하여 높은 승압효과를 얻기 위한 멀티레벨 인버터에 대한 관심이 높아지고 있다. 본 논문은 FPGA 기반 멀티레벨 인버터용 스위칭 함수를 구현하고자 한다. FPGA는 프로그램 가능한 로직 디바이스로써 풀 디지털 스위칭함수를 구현하는 효율적이다. 본 논문에서는 FPGA 기반 스위칭 함수를 구현하기 위해서 마이크로프로세서로부터 출력되는 클럭과 동기신호로 독립적으로 구동이 되도록 하였다.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 춘계학술대회논문집
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• pp.319-324
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• 2005

The interface between host processor and the ShortStack Micro Server may be a Serial Communication Interface(SCI). The LonWorks control module with a high performance is developed, which is composed of the 8 bit PIC Microprocessor for host processor and the smart neuron chip for the ShoretStack Micro Server. This intelligent control board is verified as proceeding the various function tests from experimental system with an boost pump and inverter driving systems. It is also confirmed that the developed control module provides stably 0-10VDC linear signal to the input signal of inverter driving system for varying the induction motor speed. Thus, the experimental results show that the fabricating intelligent board carried out very well the various functions in the wide operating ranges of boost pump system. This developed control module expect to apply to industrial fields to require the comparatively exact control and monitoring such as multi-motor driving system with inverter, variable air volume system and the boost pump water supply systems.

• Journal of Power Electronics
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• 제16권1호
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• pp.173-181
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• 2016

In this paper, a new technique for harmonic optimization in cascaded H-bridge 7-level inverters is proposed. The suggested strategy is based on minimizing an objective function which simultaneously optimizes the converter utilization and Total Harmonic Distortion (THD). The Switch Utilization Ratio (SUR) is formulized for both the phase and line-line voltages of a 7-level inverter and is considered in the final objective functions. Based upon the SUR formula, utilization ratio enhancement will reduce the value of feeding DC links, which improves the efficiency and lifetime of the circuit components due to lower voltage stresses and losses. In order to achieve more effective solution in different modulation indices, it is assumed that the DC sources can be altered. Experimental validation is presented based on a three-phase 7-level inverter prototype.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.615-619
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• 2009

There are many increasing demands for efficient high power density of auxiliary power unit(APU) for high speed traction application. Many techniques have been proposed to measure the voltage flicker on the traditional pulse width modulation(PWM) inverter. This paper proposes a novel functionality of the static inverter on the APU to mitigate the voltage flicker and regulate the output voltage. A new control algorithm for the inverter based on the Hilbert transform(HT) is presented. The HT is employed as an effective technique for tracking the voltage flicker levels in APU systems. Simulation results are provided to verify the tracking capabilities of the HT and to evaluate the performance of the proposed DG interface for multi-function operation.