• Proceedings of the KIEE Conference
• /
• 2006.07c
• /
• pp.1687-1688
• /
• 2006

This paper presents the results of a grid-connected photovoltaic (PV) system modeling that contain incremental conductance MPPT(Maximum Power Point Tracking) controller by PSCAD/EMTDC simulator and investigates the influence that tan occur in the grid-connected PV system from aspect of power quality, i.e. voltage drop, total harmonic distortion(THD) and total demand distortion(TDD). The measured data the PV array modeling of PSCAD/EMTDC in Cheongwadae, Seoul, Korea is used in the paper.

• Proceedings of the KIEE Conference
• /
• 2003.07b
• /
• pp.1374-1376
• /
• 2003

The output of solar cell or array depends on the weather conditions such as cell temperature and insolation level. If the output of the photovoltaic system would be regularly generated under any weather conditions, it is so easy to develop the inverter, its related system, and also control algorithm. This can be performed by the VISC(virtual-implemented solar cell) system studied in this paper. And a few I-V curves are provided by the manufacturers, and so any I-V value between the given curves is unknown. The new model for solar cell is proposed which is based on the interpolation. Both simulation and experiment are executed to show the validity of the proposed VISC system.

• Proceedings of the KIEE Conference
• /
• 2009.04b
• /
• pp.240-241
• /
• 2009

본 논문에서는 다양한 아치형 태양광발전(Photovoltaic : PV) 시스템을 시뮬레이션을 통하여 구성하고 그 운전특성을 최적의 경사각을 가지는 일정 경사각 PV 시스템과 비교 분석하였다. 결과 아치형 PV 시스템의 경우 모두 PV 어레이 경사각이 $30^{\circ}$인 일정 경사형 시스템에 비하여 9% 이상의 큰 차이가 남을 알 수 있었으며, 최적의 아치경사각은 $10^{\circ}\sim30^{\circ}$임을 알 수 있었다.

• Proceedings of the KIPE Conference
• /
• 2001.07a
• /
• pp.46-49
• /
• 2001

An investigation into power conditioners that interface with photovoltaic array and utilities has been completed. The rating for this investigation is residential system(3-5kVA) that interface with a 220V single phase utility connection. As the result of this investigation, a 3kVA high frequency PWM IGBT inverter feeding a high frequency isolation transformer with a sinusoidal current wave was selected. The output of the transformer rectified with a diode bridge rectifier. four IGBT, used as 60Hz switched, reverse the polarity of the rectified current on every other half cycle of the utility voltage. Even though the high frequency link system used more power semiconductors, a net size, weight, and parts cost saving result compared to the other systems due to elimination of 60Hz transformer.

• Proceedings of the KIPE Conference
• /
• 2014.07a
• /
• pp.369-370
• /
• 2014

태양광 PCS개발과정에서는 온도나 방사량 등을 변화시키며 태양전지 패널의 I-V곡선을 모사할 수 있는 태양광 시뮬레이션 모델이 필요하다. 이러한 용도로 볼 때 특히 다이오드 기반의 등가회로 모델은 물리적인 성질을 바탕으로 태양광 패널의 특성을 비교적 정확히 설명할 수 있으나 특유의 비선형성으로 인하여 복잡한 회로 모델 파라미터 추출 기법을 필요로 한다. 본 논문에서는데이터 시트값에 기반한 새로운 태양광 패널 회로 모델링 알고리즘을 제안한다. 제안한 방법의 성능을 검증하기 위해 단결정 태양광 패널의 실제 데이터를 기반으로 최대전력점 ${\pm}10%$부근의 전류오차 적분값을 기준으로 기존 방법과 정확도를 비교한 결과 20%의 정확도 개선을 얻었다.

• Proceedings of the KIPE Conference
• /
• 2012.07a
• /
• pp.435-436
• /
• 2012

본 논문은 가변 조정계수를 이용한 적응형 MPPT 제어 기법을 제안한다. MPPT 제어 루프가 소신호 모델링을 통해 구성되며, PV array 의 동작점에 상관없이 MPPT 제어의 성능을 일정하게 유지하기 위한 가변 조정계수가 결정된다. 가변 조정계수는 오차에 대한 근사화된 곡선맞춤 다항식을 통해 결정되며, 이를 통해 사용자가 원하는 MPPT 의 동특성과 안정성을 전 MPPT 영역에 걸쳐 확보할 수 있다. 제안된 MPPT 기법의 타당성은 3KW 급 시스템에 대한 실험을 통해 검증한다.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.61 no.1
• /
• pp.75-79
• /
• 2012

Maximum power point tracking(MPPT) techniques are used in photovoltaic systems to maximize the PV array output power by tracking continuously the maximum power point which depends on panels temperature and on irradiance conditions. This paper proposes a variable step size MPPT algorithm which can improve the MPPT speed and accuracy. Depending on insolation and temperature, the MPPT controller gives optimized step size. The effectiveness of the proposed system is verified thorough PSIM simulation and experiments on a 50[W] prototype. The experimental results confirm that the PV power of the improved P&O method is higher than that of the traditional P&O method.

• Proceedings of the KIPE Conference
• /
• 2010.11a
• /
• pp.224-225
• /
• 2010

This paper proposes a battery energy storage system using a photovoltaic generation system. The proposed system consists of a grid, battery and PV array. Considering a daily load profile, radiation and battery, operation modes are divided. An algorithm is presented based on modes. In the paper, operation modes and algorithms are verified through simulations.

• Journal of Bio-Environment Control
• /
• v.22 no.3
• /
• pp.220-227
• /
• 2013

This study examined the electric power quantity derived from solar radiation after installing a photovoltaic power generation system on the rooftop of building adjacent to a greenhouse with a view to reducing the operating expenses of the greenhouse by securing electric energy required to run it. Results of the study can be summed up as follows: The maximum, mean, and minimum solar radiation on the horizontal plane was $26.1MJ{\cdot}m^{-2}$, $14,0MJ{\cdot}m^{-2}$, and $0.6MJ{\cdot}m^{-2}$, respectively and individual the daily electric energy generated was about 6.1 kWh, 3.7 kWh, and 0.01 kWh. The cumulative total amounts of solar radiation and electric energy was about $4,378.2MJ{\cdot}m^{-2}$ and 1,163.2 kWh, respectively. Maximum, mean and minimum cumulative electric energy consumed through each load respectively was 4.5 kWh, 2.4 kWh, and 0.0 kWh and the cumulative electric energy were 739.2 kWh, which accounted for about 63.5% of generated power. In case of the mean amount of power consumption of the system used for this study, the small capacity of heater and the short operating hours meant there was enough power; while big capacity of heater led to a shortage, and if the array surface temperature increased relatively, the energy became proportionate to solar radiation and generated power does not increase. The correlation coefficient between the two factors was 0.851, which indicates a high correlation coefficient.

• Journal of the Korean Solar Energy Society
• /
• v.30 no.6
• /
• pp.73-80
• /
• 2010

This study was conducted to estimate the relative performance of modules with changed characteristics due to long term exposure to the outdoor environment, with a specially made test device for simultaneous measurement of real time power output from the photovoltaic array, taking into account the inclined panel, direct irradiation, power being generated, temperature as well as the optimal analysis timing. In terminology description, M is an abbreviation of module and Group A, Group B are 10 modules series connection (1~10 of M), (11~20 of M) for each of them respectively. The overall mean voltage difference of M-18 with the lowest power output and M-14 with the highest output is-2.13V and it was identifiable that voltage difference was more concentrated to Group B. In addition, in case of M-2 and M-7, M-8, when compared with M-14, the overall mean voltage difference was -0.92V, -1.56 and -0.91V respectively showing the more concentration to Group A. When the temperature of module went up by $1^{\circ}C$, the mean voltage was reduced by 0.35V. For current, Group A was lower than Group B by-0.022A and the ratio of each group was 49.68% and 50.32% respectively, presumably the module with deteriorated properties were more concentrated to Group A relatively. From the comparison of relations with the comprehensive accumulation, M-2, M-7, M-8, M-16 and M-18 were those with deterioration of performance to the worst, thereby requiring precision examination. In comparative efficiency, M-14 was the most excellent one as 12.19% while M-18 as 10.53% was identified that its efficiency was comparatively rapidly reduced.