• Journal of international Conference on Electrical Machines and Systems
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• 제2권2호
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• pp.225-231
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• 2013

Low voltage ride through capability augmentation of a hybrid micro-grid system is presented in this paper which reflects enhanced reliability in the system. The control scheme involves parallel connected multiple ac-dc bidirectional converters. When the micro-grid system is subjected to a severe voltage dip by any transient fault single power converter may not be able to provide necessary reactive power to overcome the severe voltage dip. This paper discusses the control strategy of additional power converter connected in parallel with main converter to support extra reactive power to withstand the severe voltage dip. During transient fault, when the terminal voltage crosses 90% of its pre-fault value, additional converter comes into operation. With the help of additional power converter, the micro-grid system withstands the severe voltage fulfilling the grid code requirements. This multiple converter scheme provides the micro-grid system the capability of low voltage ride through which makes the system more reliable and stable.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 추계학술대회 논문집
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• pp.37-41
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• 2009

In this paper, we propose to research the possibility of using a photovoltaic system and supercapacitor combined with a high speed microturbine. This hybrid energy system work as atand-alone mode or grid-connected mode as it will be a part of building micro-grid. Simple dynamic models of photovoltaic, microturbine systems and supercapacitor banks are proposed. their models are developed by Matlab/Simulink tool. Two important results are carried out to find power control effectiveness in case of with supercapacitor bank and without one. At least, simulation results show the effectiveness on the power control at AC busbar of hybrid energy system as building micro-grid system.

• 조명전기설비학회논문지
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• 제23권11호
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• pp.84-93
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• 2009

In this paper, we propose to study the possibility of using a photovoltaic system combined with a high speed micro-turbine. This hybrid system can work as stand-alone system or grid connected system as it will be a part of a micro-grid. Initially, we propose Matlab/Simulink dynamic models of photovoltaic, micro turbine systems and supercapacitor. Then, we carry out a simulation comparison of the two systems, this is, with supercapacitor and without supercapacitor bank. We show that supercapacitor bank as short-term storage device was necessary to reduce the fast fluctuation of power in the case of sensitive loads. It is verified the simulation results of Matlab/Simulink based hybrid power system represent the effectiveness of the suggested hybrid power system.

• 한국정밀공학회지
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• 제29권9호
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• pp.958-963
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• 2012

Characteristics of off-grid hybrid renewable energy sources for high mountain villages are discussed. Considering reliability of electric power generation, Photovoltaic (PV)-wind hybrid and PV-hydro hybrid system are suggested. Connecting two or more villages with these hybrid systems, an extended hybrid off-grid can be formed. Sustainability of entire system is important in design of off-grid system, and income generation of the village people using the electricity should be considered.

• 융합정보논문지
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• 제9권1호
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• pp.68-73
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• 2019

본 연구는 스마트분전반 MG(;Micro-Grid) 구성의 중심축으로 모듈형 하이브리드 발전원과 DC버스를 통하여 링크를 갖으며 표준소켓을 사용하여 불법연결을 감지 차단하는 기능을 부여하고, 전력계통의 안정화를 달성함을 목적으로 한다. 전력변환장치, 스마트분전반, 통합제어시스템의 개발과 효율적인 수요관리가 필요하며, MG 전체시스템과의 호환성이 절실하다. 이는 공통 전력 연결 규약으로 안전하고 누구나 연결을 쉽게 할 수 있는 하이브리드발전시스템으로 데이터 관리가 용이해지고 다양한 제조사의 시스템 확대설치에 대한 대비가 가능하다.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.1112-1118
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• 2014

In island and backcountry areas, electrical power is usually supplied by diesel generators. It is difficult for small scale diesel generators to have an economy of scale owing to the usage of fossil fuels to produce electricity. Also, there is a problem of carbon dioxide emissions that brings some environmental pollution to the entire region of the area. For solving those, this paper proposes a design method of autonomous micro-grid to minimize the fossil fuels of diesel generator, which is composed of diesel generator, wind turbine, battery energy storage system and photovoltaic generation system. The proposed method was verified through computer simulation and micro-grid operation system.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 추계학술대회 논문집
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• pp.273-277
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• 2009

This paper presents a basic energy performance data of micro gas turbine, Renewable Energy(BIPV and Solar Collector System, geothermal system) and a hybrid energy system(geothermal system and microturbine) installed in Hospital Building. The efficiency of solar collector and BIPV system was 30%, 10% individually, and lower than micro gas turbines. Micro gas turbines are small gas turbines that bum gaseous and liquid fuels to produce a high-energy exhaust gas and to generate the electrical power. Recently, the size range for micro gas turbines is form 30 to 500kW and power-only generation or in combined heat and power(CHP) systems. Finally, in energy performance aspect, Micro gas turbine system and hybrid energy system were high-efficiency system in hospital building. Hybrid energy system also give us a powerful alternative energy system economically.

• 한국태양에너지학회 논문집
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• 제29권4호
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• pp.41-47
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• 2009

Wind/diesel hybrid operation can be one of the most effective option for electrical power production at a remote area such as Antarctica. The king Sejong station at Antarctica relies its power production on diesel engines and diesel oil is supplied every other year by ships. However, the oil transportation processes are liable to potential oil spillage caused by the floating ice around the King George island. The long-term storage of the oil at the station can also contaminate the surrounding soils. A l0kW wind turbine has been installed to save oil consumption and operated in connection with the diesel generators since 2006. The diesel engine that operated poorly during the first year of installation was replaced in 2008 to enhance power production an recent measurements indicate that both diesel power quality and the wind turbine availability have been dramatically improved by the replacement. This report discusses electrical power qualities of wind/diesel hybrid system operating at an isolated micro gird located in the king Sejong station. Our experience reveals that the similar technologies can be applied to domestic islands, for example, in the south sea.

• 신재생에너지
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• 제10권3호
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• pp.22-30
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• 2014

The isolated self-generating electricity with diesel engine generator has been used in islands far away from main land. It costs high because of increasing oil price, and unsafe to have supplying oil and its related components by ship due to unexpectable marine conditions. Therefore there is the need for the hybrid system of renewable energy like wind or solar energy systems with oil engine generator, which can reduce oil use and extend oil supplying period. In this study, the feasibility of such hybrid system with smart micro grid on the eight islands of Jeon-nam province is surveyed to find good place for the demonstration test of the hybrid system. In each island, 3 wind turbine systems of 10 kW and photovoltaic of 20 kW are tested with already installed diesel engine. The performance and costs of the hybrid system in each island are compared in the given conditions of solar and wind energy potential. As a result of the study, Jung-ma island is recommended for the optimum place to make real field demonstration test of isolated hybrid generating and smart grid systems.

• Journal of international Conference on Electrical Machines and Systems
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• 제2권3호
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• pp.367-374
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• 2013

The electrical vehicles (EV) with vehicle-to-grid (V2G) capability can be used as loads, energy sources and energy storage in MicroGrid integrated with renewable energy sources. The output power of generators will be reallocated in the considering of V2G. An intelligent unit commitment (UC) with V2G for cost optimization is presented in this paper. A new constraint of UC with V2G is considered to satisfy daily use of EVs. A hybrid optimiza-tion algorithm combined Binary Particle Swarm Optimization (BPSO) with Lagrange Mul-tipliers Method (LMM) is proposed. The difference between results of UC with V2G and UC without V2G is presented.