• KIEAE Journal
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• v.14 no.6
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• pp.87-92
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• 2014

The objectives of this study are to investigate input variables of photovoltaic generation programs and to compare their prediction to actual generation of photovoltaic system in the C city hall and the C city sewage treatment plant. We investigated the actual amount of generation, the forecast amount of generation, the amount of solar radiation data, and calculated the relative errors. We simulated the photovoltaic system of C city hall and the C city sewage treatment plant located in Chungju using existing programs, such as SAM, RETSCREEN, HOMER, PV SYST, Solar Pro. The result of this study are as follows : Through examining the relative errors of monthly predicted and actual generation data, monthly generation data showed big errors in winter season?. Except winter season, actual amount of generation and the predicted amount of generation showed no large errors.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.110.1-110.1
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• 2011

This study analyzed the performance of long term operation photovoltaic system The 50 kWp grid connected photovoltaic system which was installed at KEPRI site in 1999 has been operated more than 12 years. In order to acquire long term operation characteristics of medium size photovoltaic system, the operation test data related on power generation electricity and capacity factor of 50 kWp system, which have been collected since 1999, were analysed. From the analysing results, 57.7 MWh in annual power generation electricity of 50 kWp photovoltaic system in 1999 has been decreased 49.1 MWh in 2005 and reached 38.0 MWh in 2010. In addition to, the capacity factor of 50 kWp photovoltaic system also showed 13.2 % in 1999, 11.2% in 2005 and finally reached 8.8% in 2011. The operation test data showed a trend of decreasing of generation electricity and capacity factor during the 12 years operation time and we guessed that was caused by solar cell performance degradation and decreasing of PCS system efficiency.

• Journal of Construction Engineering and Project Management
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• v.3 no.3
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• pp.23-34
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• 2013

As climate change and environmental pollution become one of the biggest global issues today, new renewable energy, especially solar photovoltaic (PV) system, is getting great attention as a sustainable energy source. However, initial investment cost of PV system is considerable, and thus, it is crucial to predict electricity generation accurately before installation of the system. This study analyzes the loss ratio of solar photovoltaic electricity generation from the actual PV system monitoring data to predict electricity generation more accurately in advance. This study is carried out with the following five steps: (i) Data collection of actual electricity generation from PV system and the related information; (ii) Calculation of simulation-based electricity generation; (iii) Comparative analysis between actual electricity generation and simulation-based electricity generation based on the seasonality; (iv) Stochastic approach by defining probability distribution of loss ratio between actual electricity generation and simulation-based electricity generation ; and (v) Case study by conducting Monte-Carlo Simulation (MCS) based on the probability distribution function of loss ratio. The results of this study could be used (i) to estimate electricity generation from PV system more accurately before installation of the system, (ii) to establish the optimal maintenance strategy for the different application fields and the different season, and (iii) to conduct feasibility study on investment at the level of life cycle.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.375-385
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• 2013

As climate change and environmental pollution become one of the biggest global issues today, new renewable energy, especially solar photovoltaic (PV) system, is getting great attention as a sustainable energy source. However, initial investment cost of PV system is considerable, and thus, it is crucial to predict electricity generation accurately before installation of the system. This study analyzes the loss ratio of solar photovoltaic electricity generation from the actual PV system monitoring data to predict electricity generation more accurately in advance. This study is carried out with the following five steps: (i) Data collection of actual electricity generation from PV system and the related information; (ii) Calculation of simulation-based electricity generation; (iii) Comparative analysis between actual electricity generation and simulation-based electricity generation based on the seasonality; (iv) Stochastic approach by defining probability distribution of loss ratio between actual electricity generation and simulation-based electricity generation ; and (v) Case study by conducting Monte-Carlo Simulation (MCS) based on the probability distribution function of loss ratio. The results of this study could be used (i) to estimate electricity generation from PV system more accurately before installation of the system, (ii) to establish the optimal maintenance strategy for the different application fields and the different season, and (iii) to conduct feasibility study on investment at the level of life cycle.

• Proceedings of the KIEE Conference
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• 2000.11b
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• pp.381-383
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• 2000

The photovoltaic power generation system has a great future as clean energy instead of fossil fuel which has many environmental problems such as exhausted gas or air pollution. In a utility interactive photovoltaic generation system, a three-phase inverter is used for the connection between the photovoltaic array and the utility. This paper presents a three phase inverter for photovoltaic power system with current controller, voltage controller, PLL control system and the phase detector of interactive voltage by using da transformation. The proposed inverter system provides a sinusoidal ac current for domestic loads and the utility line with unity power factor. The results of the operated from January to October show the system characteristics.

• Proceedings of the KIEE Conference
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• 2006.04b
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• pp.355-357
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• 2006

A study of the photovoltaic generation system tend to concentrate its importance on specific filed such as analysis of photovoltaic characteristic, improvement of a inverter, and controller. In this paper, a practical facility of the photovoltaic generation system and connection of its organization are presnted with process of 1.2kW prototype. From the results of monitoring system which is for reliability and analysis of the photovoltaic generation system, stability of the system was confirmed.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.5
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• pp.157-162
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• 2020

In the existing photovoltaic generation system, the system equipped with the reflecting plate is a method in which solar energy (insolation) is concentrated on the surface of the photovoltaic module. However, the solar energy (insolation) lost by being reflected back through the solar module is not considered. Although a method of increasing the amount of power generated by installing a reflector around the solar modules has been proposed, this affects the power generation degradation caused by the shading of other solar modules. Therefore, in order to improve this problem, in this paper, 1) without affecting the development of photovoltaic module according to the shade, 2) photovoltaic module using a reflector rotating the solar energy (insolation) lost by the solar module Study and suggest how to join again. Therefore, the loss of solar energy (insolation) can be minimized through the method of recycling the solar energy according to the countless reflection angle of the lost solar energy (insolation). As a result, it is possible to increase the amount of power generation of the photovoltaic generation system by maximizing the amount of power generation for the same solar radiation.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.05a
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• pp.353-356
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• 2008

This paper is proposed that the photovoltaic/fuel cell hybrid generation system for the stand-alone system. In case of the photovoltaic generation system, it depends on the weather condition, irradiation and so on... On the contrary, fuel cell has not this limitation. It can be interactive generation system between photovoltaic and fuel cell. This paper simulated stand-alone co-generation system based on the control of DC link. Moreover, 1[kw] BLDC motor system with speed and hysteresis current controller is used for the proposed system.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.3
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• pp.532-539
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• 2007

Photovoltaic power generation system is one of new renewable energy sources. Such distributed power generation system has important issues for the system management ad operating after its installation. To solve the problem, remote monitoring and control systems can be employed. In this paper, LabVBEW based monitoring and control system is proposed for efficient management and operation of the photovoltaic power generation system. Interface method between monitoring part and DSP controller is given in detail. The proposed system is verified through experiments using a grid-connected photovoltaic power generation system.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.109.2-109.2
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• 2011

A photovoltaic system is getting the spotlight for a environment-friendly energy source. But its location is limited because a lot of land is necessary for photovoltaic arrays. Nevertheless, its dissemination is rapidly increasing more than 40 % every year and exceeded about 400 MW in 2009. The radical growth of a photovoltaic system aggravated a lack of sites, so that forests and farmland were destroyed. It is demanded to make use of a vacant lot or little piece of land for the way to solve the lack of sites and improve the location requirements for a photovoltaic system. General photovoltaic arrays are consist of a single layer structure and needs enough separation distances to maximize the amount of solar radiation and to eliminate influences by the shadow of other arrays. So that a large amount of land is required for the site. The solar cell arrays with long separation distances can not be placed in a small vacant lot and its site application efficiency is low. This study optimized photovoltaic arrays as multilayered structure with movable sleeves for the efficient photovoltaic in a small site. The existing photovoltaic arrays with a single layer structure were fixed or tracking systems. In this experimental equipment, photovoltaic arrays attached to the multilayers have rectilinear movement and rotary motion using sleeves. Therefore, shadow influences were removed and the generation capacity was improved. On the simulation result, generation increased by about 30% in the same site considering shadow influences and so on.