• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.354-359
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• 2012

With the long-term use of fossil fuel, the whole world is suffering from serious abnormal changes in weather caused by global warming. For this reason, many countries are reducing greenhouse gas emissions out of obligation and the allowable emissions are assigned to each country. Korea is also putting much effort into reducing greenhouse gas emissions by 30 percent against BAU(Business As Usual) by 2020, and is pushing ahead with several projects such as 'Million Green Home' and 'Hatsal Gaduk Home' to expand the use of new renewable energy in house as part of its policy. This study was designed to come up with improvements and help to expand photovoltaic facilities, by investigating and analyzing the current state of photovoltaic facilities in the country and problems in installing them through an in-site reconnaissance and a survey in Jecheon area. As the result, it was found that residents in the area were inadequate to operate and install photovoltaic facilities, lacked awareness of them and felt burdened economically by managing and installing them, although they had a high awareness of solar energy and photovoltaic facilities are constantly increasing with governmental support. In conclusion, it is considered that as improvements, operational effects should be increased through development of techniques, factors to reduce the effects in operating them due to insufficient management and installation should be removed and awareness of residents need to be improved through long-term plans, political support and education of the government.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권1호
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• pp.97-115
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• 2022

Smart power grid is a user friendly system that transforms the traditional electric grid to the one that operates in a co-operative and reliable manner. Demand Response (DR) is one of the important components of the smart grid. The DR programs enable the end user participation by which they can communicate with the electricity service provider and shape their daily energy consumption patterns and reduce their consumption costs. The increasing demands of electricity owing to growing population stresses the need for optimal usage of electricity and also to look out alternative and cheap renewable sources of electricity. The solar and wind energy are the promising sources of alternative energy at present because of renewable nature and low cost implementation. The proposed work models a smart home with renewable energy units. The random nature of the renewable sources like wind and solar energy brings an uncertainty to the model developed. A stochastic dual descent optimization method is used to bring optimality to the developed model. The proposed work is validated using the simulation results. From the results it is concluded that proposed work brings a balanced usage of the grid power and the renewable energy units. The work also optimizes the daily consumption pattern thereby reducing the consumption cost for the end users of electricity.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 전력전자학술대회 논문집
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• pp.289-290
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• 2012

This paper proposes a new active snubber boost PFC converter to provide a zero-voltage-switching (ZVS) turn-on condition and reduce electromagnetic interference (EMI) noise in home appliances and renewable energy applications, including solar or fuel cell electric systems. The proposed active snubber circuit enables a main boost switch of the boost-type PFC or grid converter to turn on under a ZVS condition and reduce the switching losses of the main boost switch. Moreover, for the purpose of a specialized intelligent power module (IPM) fabrication, the proposed boost circuit is designed to satisfy some design aspects such as space saving, low cost, and easy fabrication. Simulation and experimental results of a 2kW IPM boost-type PFC converter are provided to verify the effectiveness of the proposed active snubber boost circuit.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.93-98
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• 2011

A photovoltaic/thermal(PVT)collector produces both thermal energy and electricity simultaneously. The heat from PV modules should be removed for better electrical performance, and can be converted into useful thermal energy. A PVT module is a combination of PV module with a solar thermal collector which forms one device that converts solar radiation into electricity and heat. In general, there are two different types of PVT module: glazed PVT module and unglazed PVT module. On the other hand, two types of the PVT module can be distinguished according to absorber on PV module rear side: the sheet-and-tube absorber PVT module and the fully wetted absorber PVT module. The absorber collector plays an important function in PVT system. It cools down the PV module, while collecting the thermal energy produced in the form of hot water. The aim of this study is to compare the electrical and thermal performance of two different PVT collectors, one with the rectangular tube and the other with fully wetted absorber PVT collectors. For this paper, the PVT collectors with two different types of thermal absorber were made, and both the thermal and electrical performance of them were measured in outdoor, and the results were compared. The experimental results were analyzed that the thermal efficiency of the fully wetted absorber PVT collector is about 8.7% higher than the sheet-and-tube absorber PVT collector, and for the electrical efficiency, the fully wetted absorber PVT collector had about 7% higher than the rectangular tube absorber.

• 에너지공학
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• 제29권1호
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• pp.44-51
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• 2020

ESS의 중요성은 네트워크 신뢰성 저하 및 재생 가능 에너지원의 확장으로 인한 전력 수요의 안정화로 인해 강조되었다. ESS (Energy Storage System)는 남은 전력을 저장하고 전력 수요를 충족시키기 위해 필요할 때 이를 사용하며 주로 태양 광 및 풍력과 연계하여 ESS 시스템을 구축한다. 본 논문에서는 낮은 일사량에 효과적인 Master-Slave 방법을 이용한 가정용 PV 충전 모듈을 제안한다. 모듈을 설계 한 후 고속 MPPT 알고리즘이 적용되어 PV 모듈의 비선형 출력 특성에서 최대 출력을 생성한다. PV 충전 모듈의 입력에 대한 평균 전력 값은 296.90 W, 출력 전력은 289.60 W로 평균 97.54 %의 전력변환 효율을 보인다.

• Transactions on Electrical and Electronic Materials
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• 제13권5호
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• pp.256-261
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• 2012

Recently, many photovoltaic systems (PV systems) including solar parks and PV farms have been built to prepare for the post fossil fuel era. To investigate the degradation process of the PV systems and thus, efficiently operate PV systems, there is a need to visually monitor PV systems in the range of infrared ray through the Internet. For efficient visual monitoring, this paper explores a multithreaded implementation of a recently developed HEVC standard whose compression efficiency is almost two times higher than H.264. For an efficient parallel implementation under a meshbased 64 multicore system, this work takes into account various design choices which can solve potential problems of a two-dimensional interconnects-based 64 multicore system. These problems may have not occurred in a small-scale multicore system based on a simple bus network. Through extensive evaluation, this paper shows that, for an efficient multithreaded implementation of HEVC intra prediction in a mesh-based multicore system, much effort needs to be made to optimize communications among processing cores. Thus, this work provides three design choices regarding communications, i.e., main thread core location, cache home policy, and maximum coding unit size. These design choices are shown to improve the overall parallel performance of the HEVC intra prediction algorithm by up to 42%, achieving a 7 times higher speed-up.

• 한국융합학회논문지
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• 제12권2호
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• pp.21-28
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• 2021

본 연구에서는 가전기기 5종에 대해 실제 측정 전력 데이터를 이용하여 딥러닝 기반의 NILM 기법을 제안하고 그 효용성을 검증 하고자 한다. 약 3주간 중앙 전력 측정 장치 및 5종 가전기기(냉장고, 인덕션, TV, 세탁기, 공기청정기)의 유효전력을 개별 측정하였다. 실측 데이터의 전처리 방법을 소개하고 Spectogram 분석을 통해 가전 기기별 특징을 분석하였다. 가전기기별 특징을 학습 데이터셋으로 구성하였다. 중앙 전력 측정 기기와 가전기기 5종에서 측정된 모든 전력 데이터를 시계열 매핑하여 시계열 데이터 분석에 우수한 RNN 계열의 LSTM 신경망을 이용해 학습을 수행하였다. 메인 중앙 전력 측정 장치의 전력 데이터만으로도 5종 전력 신호를 분해해낼 수 있는 알고리즘을 제안하였다.

• 한국전자통신학회논문지
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• 제16권6호
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• pp.1183-1194
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• 2021

전통적으로 전력시스템은 공급체계의 말단에 있는 소비자의 위치에서 보면 중앙집중화된 구조를 갖고 있다. 그러나 최근 수 십년간 지붕형 태양광, 영농형 태양광, 소형 풍력터빈, 배터리저장장치 및 스마트 가전품과 같은 분산에너지원의 등장을 보아왔다. 분산에너지원의 등장에 따라 배전계통 운전원의 역할도 확장된다. 확장된 분산전원의 진출은 배전망이나 송전망의 전통적인 계획과 운영에 영향을 주는 전력계통의 역조류와 예측성을 어렵게 할 수 있다. 이는 전형적인 계통계획, 정비 및 망관리, 정전할당 등 배전계통 운전원이 갖는 기능이 변경되어야 할 필요성을 증폭시킨다. 이 연구의 목적은 다중 분산전원을 갖는 미래 배전운전시스템을 설계하고 제안된 배전시스템 모델을 HILS로 구현 및 검증하는 것이다. 시험결과를 보면 제안된 배전시스템이 정상 영역에서 운전되고 배전선로 손실이 감소된다는 것을 보여준다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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• pp.179-184
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• 2011

The development of new energy has attracted consideration attention due to the high oil price and environmental problems. In advanced country, they have tried to carry out a long range plan for energy. We need to develop new energy for Low Carbon Green Growth in Korea. The building is 30% among ratio of energy consumption in Korea. And in the past, heating energy was high ratio for energy using at home. But recently, the demand for cooling energy keeps growing due to rising average temperature on the earth and improvement of life quality. In this situation, the energy of lake water and ocean water has studied to utilize in advanced country because of low temperature at underwater. But the study for deep water is still a lot left to do. In this study, we analyzed district cooling system and the present condition. Analyzing the deep lake water cooling system in Toronto, we found an application of district cooling system using deep ocean water. Deep lake water uses heat source for district cooling and water source for city in Toronto. So reducing the initial cost, this city had economic effect. When DLWC was applied at existing building, the heat exchanger was installed instead of cooling tower and refrigerator. And the heat exchanger used to connect main pipe with cool water on city. System using deep ocean water can be applied as a similar way to supply cool water from lake to building.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2010년도 춘계학술대회
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• pp.871-874
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• 2010

세계적으로 에너지원의 고갈, 기후 환경 변화, 전력수요 증가에 따라 인류 절대적 과제에 대한 결책으로 스마트 그리드에 대한 요구가 증대되고 있으며, 특히 분산형 전원에 대한 관심이 높아지고 있다. 이 추세에 다라 단위 규모의 분산형 전원의 형태로 댁내 분산형 전원 시대를 예고하고 있다. 하지만 현재 가장 보편적으로 사용하고 있는 신재생에너지원으로써 풍력, 태양광 에너지 발전의 경우 그 발전량이 자연의 변화에 매우 민감하기 때문에 전기품질의 균일성의 문제를 가지고 있다. 따라서 본 논문에서는 이를 해결하기 위해서는 기후 정보(meteorological sensor data)의 실시간 모니터링을 기반으로 하는 에너지 관리 방법을 제시하고자 한다. 현재 스마트그리드 분야에서 USN 기반의 킬러앱이 부재한 상황에서 무선 센서네트워크 기술을 활용한 기후 센서 데이터 수집 및 제어 방식을 적용한 댁내 분산 전력 관리 방법에 대해 제안한다. 이는 다른 통신방식에 비해 설치 비용 및 유지보수 차원에서 효율적이라고 판단한다. 즉, 전력 관리에 USN 기법을 융합한 EMS(Energy Management System) 모델을 제시함으로써 기후 데이터 모니터링 및 분석, 이에 따른 발전량 예측, 신재생에너지와 기존 전력의 효율적인 분배 제어 방법을 구체화함으로써 궁극적으로 제로에너지 홈을 구현하기 위한 기반을 마련하는 것이 본 논문의 목표이다.