상용 태양전지 셀을 이용한 소형 SAR 위성의 태양전지 어레이 개념설계 및 경량화 연구

김태득(Kim Tae-Deuk) 한국태양에너지학회 2017 한국태양에너지학회 논문집 Vol.37 No.5

Solar cells have widely been utilized for a satellite to convert sunlight energy into electricity in space. Many different types of solar cells appropriate for each satellite program are available in current markets, which enables us to construct a solar array light and small often required from a low Earth orbit (LEO) synthetic aperture radar (SAR) satellite. Thus, it is important to choose a proper solar cell satisfying the requirements of mass and size for the solar array. In this article, we have surveyed typical suppliers and have discussed some characteristics of solar cells. Conceptual design examples of the solar array for LEO SAR satellites using several types of solar cells have been performed to show the pros and cons of solar cells by comparison of the total mass and size necessary for the solar array.

Simplified Analytical Model for Investigating the Output Power of Solar Array on Stratospheric Airship

Zhang, Yuanyuan,Li, Jun,Lv, Mingyun,Tan, Dongjie,Zhu, Weiyu,Sun, Kangwen The Korean Society for Aeronautical and Space Scie 2016 International Journal of Aeronautical and Space Sc Vol.17 No.3

Solar energy is the ideal power choice for long-endurance stratospheric airships. The output performance of solar array on stratospheric airship is affected by several major factors: flying latitude, flight date, airship's attitude and the temperature of solar cell, but the research on the effect of these factors on output performance is rare. This paper establishes a new simplified analytical model with thermal effects to analyze the output performance of the solar array. This model consisting of the geometric model of stratospheric airship, solar radiation model and incident solar radiation model is developed using MATLAB computer program. Based on this model, the effects of the major factors on the output performance of the solar array are investigated expediently and easily. In the course of the research, the output power of solar array is calculated for five airship's latitudes of $0^{\circ}$, $15^{\circ}$, $30^{\circ}$, $45^{\circ}$ and $60^{\circ}$, four special dates and different attitudes of five pitch angles and four yaw angles. The effect of these factors on output performance is discussed in detail. The results are helpful for solving the energy problem of the long endurance airship and planning the airline.

Simplified Analytical Model for Investigating the Output Power of Solar Array on Stratospheric Airship

Yuanyuan Zhang,Jun Li,Mingyun Lv,Dongjie Tan,Weiyu Zhu,Kangwen Sun 한국항공우주학회 2016 International Journal of Aeronautical and Space Sc Vol.17 No.3

Solar energy is the ideal power choice for long-endurance stratospheric airships. The output performance of solar array on stratospheric airship is affected by several major factors: flying latitude, flight date, airship’s attitude and the temperature of solar cell, but the research on the effect of these factors on output performance is rare. This paper establishes a new simplified analytical model with thermal effects to analyze the output performance of the solar array. This model consisting of the geometric model of stratospheric airship, solar radiation model and incident solar radiation model is developed using MATLAB computer program. Based on this model, the effects of the major factors on the output performance of the solar array are investigated expediently and easily. In the course of the research, the output power of solar array is calculated for five airship’s latitudes of 0°, 15°, 30°, 45° and 60°, four special dates and different attitudes of five pitch angles and four yaw angles. The effect of these factors on output performance is discussed in detail. The results are helpful for solving the energy problem of the long endurance airship and planning the airline.

인공위성 태양전지판 전개해석

김경원,김선원,임재혁,이주훈,황도순,진익민,김학정,송운형,최항석 통신위성ㆍ우주산업연구회 2008 한국위성정보통신학회논문지 Vol.3 No.1

발사체로부터 분리된 위성체가 궤도상에 진입하면 가장 먼저 태양전지판을 전개한다. 태양전지판의 전개유무는 위성 임무의 성공에 관련되어 있는 매우 중요한 요소 중 하나이다. 따라서, 설계 초기 단계에서부터 태양전지판 전개해석을 통하여 태양전지판의 거동을 예측하고, 전개 중 태양전지판 주요 부위에서의 하중을 계산하여, 태양전지판 전개안전성을 점검하는 것이 반드시 필요하다. 본 논문에서는 다몸체동역학 해석프로그램을 이용하여 차세대 저궤도 위성의 태양전지판 전개해석을 수행하고, 그 결과로부터 태양전지판 전개시 안정성을 분석하였다. 또한, 전개해석시 필요한 힌지 특성 데이터는 힌지 특성 시험을 수행하여 구하였으며, 이의 결과를 전개해석에 반영하여 해석을 수행하였다. After spacecraft is separated from the launch vehicle, first of all spacecraft deploy the solar array. Solar array deployment is one of the key factors deciding the success of the spacecraft mission. Therefore, It is necessary to predict the solar array deployment motion and check the safety through calculating the load on the tape hinges of solar array using the deployment analysis in the initial design phase. In this paper, solar array deployment analysis is performed by multi-body dynamics simulation program. From the analysis results, assessment on the safety also is carried out. In addition, hinge characteristic test is fulfilled to find out hinge characteristic, and is applied to the deployment analysis.

태양전지 어레이의 경사각에 따른 실험적 연구

전 준(Joon Jeon)김충기(Chung-Gi Kim) 산업기술교육훈련학회 2018 산업기술연구논문지 (JITR) Vol.23 No.2

The most important issue in the field of production energy in these days is to eliminate pollution from the environment globally for future generations. Photovoltaic (PV) systems use solar power, which is a clean source of energy, as a way to solve these pollution problems. The production of solar cells is one of the leading semi-conductor industries in Korea. In addition, solar cells should be able to produce electricity with the highest efficiency in a variety of fields, such as electrical and electronic materials and mechanical and physical chemistry. Therefore, in Korea (located at the latitude of 35∼37 degrees), by installing a tracking Photovoltaic array system that follows the movement of the sun rather than by using a fixed array, a tracking Photovoltaic system can produce 30% more power. Though the Photovoltaic tracking system involves high maintenance costs, control technologies must be developed for high energy acquisition. Therefore, this study investigates the energy power of the solar cell through experiments involving the inclination angle of the solar cell array.

Regulated Peak Power Tracking (RPPT) System Using Parallel Converter Topologies

Ali, Muhammad Saqib,Bae, Hyun-Su,Lee, Seong-Jun,Cho, Bo-Hyung The Korean Institute of Power Electronics 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.6

Regulated peak power tracking (RPPT) systems such as the series structure and the series-parallel structures are commonly used in satellite space power systems. However, these structures process the solar array power or the battery power to the load through two cascaded regulators during one orbit cycle, which reduces the energy transfer efficiency. Also the battery charging time is increased due to placement of converter between the battery and the solar array. In this paper a parallel structure has been proposed which can improve the energy transfer efficiency and the battery charging time for satellite space power RPPT systems. An analogue controller is used to control all of the required functions, such as load voltage regulation and solar array stabilization with maximum power point tracking (MPPT). In order to compare the system efficiency and the battery charging efficiency of the proposed structure with those of a series (conventional) structure and a simplified series-parallel structure, simulations are performed and the results are analyzed using a loss analysis model. The proposed structure charges the battery more quickly when compared to the other two structures. Also the efficiency of the proposed structure has been improved under different modes of solar array operation when compared with the other two structures. To verify the system, experiments are carried out under different modes of solar array operation, including PPT charge, battery discharge, and eclipse and trickle charge.

Regulated Peak Power Tracking (RPPT) System Using Parallel Converter Topologies

Muhammad Saqib Ali,Hyun-Su Bae,Seong-Jun Lee,Bo-Hyung Cho 전력전자학회 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.6

Regulated peak power tracking (RPPT) systems such as the series structure and the series-parallel structures are commonly used in satellite space power systems. However, these structures process the solar array power or the battery power to the load through two cascaded regulators during one orbit cycle, which reduces the energy transfer efficiency. Also the battery charging time is increased due to placement of converter between the battery and the solar array. In this paper a parallel structure has been proposed which can improve the energy transfer efficiency and the battery charging time for satellite space power RPPT systems. An analogue controller is used to control all of the required functions, such as load voltage regulation and solar array stabilization with maximum power point tracking (MPPT). In order to compare the system efficiency and the battery charging efficiency of the proposed structure with those of a series (conventional) structure and a simplified series-parallel structure, simulations are performed and the results are analyzed using a loss analysis model. The proposed structure charges the battery more quickly when compared to the other two structures. Also the efficiency of the proposed structure has been improved under different modes of solar array operation when compared with the other two structures. To verify the system, experiments are carried out under different modes of solar array operation, including PPT charge, battery discharge, and eclipse and trickle charge.

태양전지 어레이에 적용 가능한 열화모듈 검출방법 개발

한창운(Changwoon Han),박승일(Seungil Park),이현석(Hyeonseok Lee) 대한기계학회 2018 大韓機械學會論文集A Vol.42 No.5

태양광 발전소는 효율적 전기 생산을 위해 태양전지 모듈을 직렬 및 병렬로 연결한 태양전지 어레이로 구성된다. 어레이를 구성하는 개별 태양광 모듈은 시간에 지남에 따라 열화가 진행되며, 태양광 어레이의 발전효율은 열화가 진행된 모듈의 발전효율에 따라 결정된다. 본 연구에서는 태양전지 모듈을 어레이에서 분리하지 않고, 열화가 진행된 모듈을 검출하는 방법을 제안한다. 이 방법은 태양광 모듈에 반투명 가림막을 설치하여 모듈의 전기적 특성을 인위적으로 변경하며 어레이 전체의 출력 곡선을 측정하고 상호 비교한다. 방법의 효과를 분석하고 제안 방법의 검증을 위해서 회로 시뮬레이션을 실시한다. 또한, 실제 태양전지 어레이에 대해서 본 방법을 적용하고 방법의 타당성을 검증한다. Solar cell modules are connected in serial and parallel in a photovoltaic system. All the solar cell modules degrade over time, and the most degraded module in an array decides the output level of the array. In this study, we suggest a health-monitoring method that makes it possible to detect the most degraded module in an array without separating the module from the array. We suggest placing a nontransparent film on a module in an array to create an artificial shading effect. It needs to monitor the current-voltage curve of the string while placing the film on the next one. We show analytically that the most degraded module can be detected by comparing all the array current-voltage curves. We demonstrated the method using an outdoor photovoltaic array.

반사경 배치 및 흡수기 형상에 따른 접시형 태양열 집열기의 복사 열손실 해석

서주현(Seo Joo-Hyun),마대성(Ma Dae-Sung),김용(Kim Yong),강용혁(Kang Yong-Heack),서태범(Seo Tae-Beom) 한국태양에너지학회 2007 한국태양에너지학회 학술대회논문집 Vol.- No.-

The radiative heat loss from a receiver of a dish solar collector is numerically investigated. The dish solar collector considered in this paper consists of a receiver and multi-faceted mirrors. In order to investigate the performance comparison of dish solar collectors, six different mirror arrays and four different receivers are considered. A parabolic-shaped perfect mirror of which diameter is 1.40 m is considered as the reference for the mirror arrays. The other mirror arrays which consist of twelve identical parabolic-shaped mirror facets of which diameter are 0.405 m are suggested for comparison. Their reflecting areas, which are 1.545 ㎡, are the same. Four different receiver shapes are a conical, a dome, a cylindrical, and a unicorn type. The radiative properties of the mirror surfaces and the receiver surfaces can vary the thermal performance of the dish solar collector so that various surface properties are considered. The Net Radiation Method that is based on the radiation heat balance on the surface is used to calculate the radiation heat transfer rate from the inside surface of the receiver to the environment. The Monte-Carlo method that is the statistical approach is adopted to predict the radiation heat transfer rate from the reflector to the receiver. Based on the calculation, the unicorn type has the best performance in receiver shapes and the STAR has the best performance in mirror arrays except the perfect mirror.

Effects of Reflectors and Receivers on the Thermal Performance of Dish-Type Solar Power Systems

Ma, D.S.,Kim, Y.,Seo, T.B.,Kang, Y.H.,Han, G.Y. 한국신재생에너지학회 2007 한국신재생에너지학회 학술대회논문집 Vol.2007 No.06

The thermal performance comparisons of the dish solar collector system are numerically investigated with mirror arrays and receiver shapes. In order to compare the performances of the dish solar collector systems, six different mirror arrays and four different receiver shapes are considered and the radiative heat flux distribution on the inside of the receiver is analyzed. A parabolic-shaped perfect mirror of which diameter is 1.5 m is considered as a reference of the mirror arrays. Five different mirror arrays of twelve identical parabolic -shaped mirror facets of which diameter are 0.4 m are proposed in this study. Their reflecting areas, which are 1.5 m², are the same. Four different receiver shapes are a dome, a conical, a cylindrical and a unicorn type. The solar irradiation reflected by mirrors is traced using the Monte-Carlo method. In addition, the radiative properties of the mirror surface can vary the thermal performance of the dish solar collector system so that the effects of the surface reflectivity and the surface absorptivity are considered. Based on the calculation, the design information of dish solar collector system for producing the electric power can be obtained. The results show that the dome type has the best performance in receiver shapes and the 2AND4INLINE has the best performance in mirror arrays except the perfect mirror.