• 한국수소및신에너지학회논문집
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• 제26권4호
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• pp.369-376
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• 2015

Recently KEPCO, KOGAS and other institutions are jointly conducting an R&D for the development and demonstration of the power generation system based on a natural gas/diesel engine on an island. As a preliminary study, co-combustion in the dual fuel engine, which is expected to produce a few mega-watts of electricity, was modeled and calculated using computational fluid dynamics (CFD). The applied key assumptions are 2-dimensional axisymmetric, transient and static volume chemical reaction. Based on the selected blending ratio, which is the key operating condition, natural gas is substituted instead of diesel fuel (basis of high heating value). Results showed that as the blending ratio increases, the reaction rate of the combustion increases and thus maximum temperature is reached more rapidly. For the optimal performance, various geometric or operational studies will further be conducted.

• 한국항해항만학회지
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• 제35권5호
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• pp.381-385
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• 2011

본 연구에서는 최대 발전량이 500kW인 서해 도서의 풍력-디젤 하이브리드 발전시스템에 대한 경제성 분석을 수행하였다. 이를 위해 해당 도서에 대한 연간 전력 부하 변동치와 바람 데이터를 수집하고 분석하였으며, 풍력을 포함하여 신재생 에너지에 대한 하이브리드 최적화 모델로 미국의 NREL에서 개발한 Homer 프로그램을 이용하였다. 풍력-디젤 하이브리드 발전시스템의 경제성을 판단하기 위해 풍속과 경유 가격을 변수로 하는 민감도 해석도 수행하였다. 그 결과, 현재의 조건에서는 경제성이 낮았으나, 풍속이 초속 3미터가 넘거나 경유 가격이 리터당 2.4달러를 초과할 경우 대상지역에도 풍력-디젤 하이브리드 발전시스템이 경제성을 갖는 것으로 평가되었다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1213-1219
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• 2008

The deterioration analysis of electric systems in diesel electric locomotives, which were used for over 30 years, was performed to understand current wear and safety information. The electric systems include electric generation, traction motors, control units, high-voltage cables, and wires. In this investigation, various types of performance testing, such as insulation resistance measurement and degradation tests, were conducted to assess the degree of current deterioration. Moreover, an infrared camera was employed to verify abnormal heating in cables and wires. In this paper, the new techniques for evaluation of deterioration in electric systems have been introduced.

• 한국지능시스템학회논문지
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• 제24권5호
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• pp.554-561
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• 2014

Hybrid wind Diesel stand-alone power systems are considered economically viable and effective to create balance between production and load demand in remote areas where the wind speed is considerable for electric generation, and also, electric energy is not easily available from the grid. In Wind diesel hybrid system, the wind energy system is the main constitute and diesel system forms the back up. This type of hybrid power system saves fuel cost, improves power capacity to meet the increasing demand and maintains the continuity of supply in the system. Problem we face in this system is that even after producing enough power through wind turbine system, considerable portion of this power needs to be dumped due to short term oversupply of power and to maintain the frequency within close tolerances. As a result remaining portion of total energy supplied comes from the diesel generator to overcome the temporal energy shortage. This scenario decreases the overall efficiency of hybrid power system. In this study, efficient Simulink modeling for wind-diesel hybrid system is proposed and some simulations study is carried out to verify the feasibility of the proposed scheme.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2000년도 춘계 학술발표회 논문집
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• pp.287-292
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• 2000

• 전기학회논문지
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• 제61권9호
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• pp.1260-1268
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• 2012

Recently, lack of power reserve margin was observed quite often. In this paper, we studied the method to secure power source for a short time, to cut the utility power peak load, and to reduce the users electricity bills. Emergency diesel generator of an office building is to be converted into a dual-fuel engine generator which is responsible for a portion of the peak load. Compared to the conventional diesel fuel generator, the proposed dual-fuel engine is able to reduce the generation power cost by dual-fuel combustion, and it also mitigates the building's utility power peak load by charging the building's peak load. If the dead resources (a group of emergency dual-fuel engine generators), as a Virtual Power Plant, are operating in peak time, we can significantly reduce future large power development costs. We investigated the current general purpose electricity bills as well as the records of the building electric power usage, and calculated diesel engine generator renovation costs, generation fuel costs, driving conditions, and savings in electricity bills. The proposed dual-fuel engine generation method reduces 18.1% of utility power peak load, and turned out to be highly attractive investment alternative which shows more than 27% of IRR, 76 million won of NPV, and 20~53 months of payback periods. The results of this study are expected to be useful to developing the policy & strategy of the energy department.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
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• pp.245-249
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• 2009

Antarctic King Sejong Station was established in King George Island, the South Pole in 1988, and has been executing the monitoring studies on the change of antarctic natural environment. As an available power, the wind energy generator has been used in the form of hybrid with mainly diesel generator. Because the wind generation power sharply changes by wind energy, it must be careful during the system operation. When the power system becomes stable, the output performance of wind energy generator becomes stable. But, in case of unstable system, the errors frequently occur on the wind energy generator and it badly impacts the power system by output of wind energy generator. The purpose of this paper is to analyze suitability while operating the system of 10kW wind energy generator at Antarctic King Sejong Station, an isolated area, and to analyze the problem and improvements by power quality.

• Journal of Electrical Engineering and Technology
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• 제10권4호
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• pp.1432-1440
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• 2015

A dynamic economic dispatch and control method is proposed to minimize the overall generating cost for a stand-alone microgrid in DongAo Island, which is integrated with wind turbine generator, solar PV, diesel generator, battery storage, the seawater desalination system and the conventional loads. A new dispatching strategy is presented based on the ranking of component generation costs and two different control modes, in which diesel generator and battery storage alternate to act as the master power source to follow system power fluctuation. The optimal models and GA-based optimization process are given to minimize the overall system generating cost subject to the corresponding constraints and the proposed dispatch strategy. The effectiveness of the proposed method is verified in the stand-alone microgrid in DongAo Island, and the results provide a feasible theoretical and technical basis for optimal energy management and operation control of stand-alone microgrid.

• 동력기계공학회지
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• 제15권5호
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• pp.16-21
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• 2011

The large scale decisive battle will be gradually reduced on the sea in the future and surface combatant ship installed advanced weapon units as well as propulsion system will be continuously increased. The high level of military technology leads to appear state-of-the-art weapon system using high power energy. As a results, fossil fuel powered main prime mover as diesel engine and gas turbine which are composed of mechanical propulsion system should be decreased from combatant ship in the near future. The new building naval combatant ship with the latest technology has electric based propulsion method of the hybrid type combined with mechanical and electrical drive. U.S. and Royal Navy, especially, select the integrated fully electric based propulsion system for the next generation combat ship and play an important roll for developing them. In this context, this paper was focused on the deduction of implications through analyzing the combatant ship propulsion system using diesel and gas turbine engine which are promoted on the worldwide.

• 에너지공학
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• 제27권2호
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• pp.49-54
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• 2018

본 연구 대상인 발전기용 커먼레일 디젤엔진은 폐엔진을 재제조한 것으로서 폐엔진의 연료분사시기는 차량 운전조건에 적합하도록 설정되어 있다. 그러나 발전기용 엔진은 회전속도가 일정하고 주로 부분부하에서 운전된다. 따라서, 발전용 엔진에 적합한 연료분사시기의 변경이 필요하고 이러한 변경에 필요한 비용과 시간은 가능한 최소화시켜야 한다. 본 연구에서는 이에 적합한 연료분사시기 변경을 적용하였으며 실제 제작에 따른 시행착오를 줄이기 위해 선행적으로 엔진성능 수치해석을 도입하였다. 해석결과, 발전기용 엔진에 적합한 연료분사시기 변경에 따라 연소 효율성을 높아져서 성능 및 연비가 증가함을 확인하였다.