• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.5
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• pp.21-33
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• 2012

This paper presents the new maximum power point tracking(MPPT) control of the photovoltaic(PV) module integrated converter(MIC) system considering the shadow influence. The output characteristics of the solar cell is a nonlinear and affected by a temperature, the solar radiation and influence of a shadow. Particularly, MIC system is very sensitive to the shadow influence because the capacity is very small. In order to increase an output and efficiency of the solar power generation, the maximum power point(MPP) obeying control are necessary. Conventional perturbation and observation(PO) and Incremental conductance(IC) are the method finding MPP by the continued self-excitation vibration. The MPPT control is unable to be performed by rapid output change affected by the shadow. To solve this problem, the new control algorithm of the multi-level in which the step value changes by output change is presented. In case there are the solar radiation, a temperature and shadow influence, the presented algorithm treats and compares the conventional control algorithm and output error. In addition, the validity of the algorithm is proved. through the output error response characteristics.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1253-1255
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• 2003

Since the residential load is an AC load and the output of solar cell is a DC Power, the photovoltaic system needs the DC/AC converter to utilize solar cell. In case of driving to interact with utility line, in order to operate at unity power factor, converter must provide the sinusoidal wave current and voltage with same phase of utility line. Since output of solar cell is greatly fluctuated by insolation. it is necessary that the operation of solar cell output in the range of the vicinity of maximum power point. In this paper DC/AC converter is three phase PWM converter with smoothing reactor. And then, feedforward control used to obtain a superior characteristic for current control and digital PLL circuit used to detect the phase of utility line.

• Journal of Korea Multimedia Society
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• v.19 no.8
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• pp.1530-1537
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• 2016

Recently, solar power generation shows the significant growth in the renewable energy field. Using the short-term prediction, it is possible to control the electric power demand and the power generation plan of the auxiliary device. However, a short-term prediction can be used when you know the weather forecast. If it is not possible to use the weather forecast information because of disconnection of network at the island and the mountains or for security reasons, the accuracy of prediction is not good. Therefore, in this paper, we proposed a system capable of short-term prediction of solar power generation amount by using only the weather information that has been collected by oneself. We used temperature, humidity and insolation as weather information. We have applied a moving average to each information because they had a characteristic of time series. It was composed of min, max and average of each information, differences of mutual information and gradient of it. An artificial neural network, SVM and RBF Network model was used for the prediction algorithm and they were combined by Ensemble method. The results of this suggest that using a moving average during pre-processing and ensemble prediction models will maximize prediction accuracy.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.361-363
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• 1996

The output of solar cell should be operated in the maximum power point, since it is greatly fluctuated by insolation and temperature. Also, since the output of solar cell is a DC power, it needs the inverter to interact with utility line. In this paper, we made composed of PV system with a chopper that control the maximum power point and the inverter that drive to the high power factor and low harmonic by use of defected and compensated utility line voltage for synchronous phase with utility line.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.4
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• pp.479-486
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• 2003

This paper presents the Performance of PV(Photovoltaic) system. the design of MPPT and the battery characteristic. The output power of PV depends on the environmental factors such as insolation and cell temperature. It is proposed that the MPPT is based on an simple power control algorithm. Furthermore the converter has to maintain the optimum duty ratio. A switching strategy of converter for battery may Protect against excessive discharge and overcharge. This paper includes discussion on system reliability power quality and effects of the randomness of the wind and the solar radiation on system design.

• 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.

• Proceedings of the KIEE Conference
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• 2004.07e
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• pp.110-113
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• 2004

PV model is presented based on the shockley diode equation. The simple model has a photo-current source, an single diode junction and a series resistance and includes temperature dependences. An accurate PV module electrical model is presented, matching with boost converter MPPT strategy and demosnstarted in Matlab for a typical general purpose solar cell. Given solar insolation and temperature, the model returns current vector and MPP.

• Journal of the Korean Solar Energy Society
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• v.36 no.5
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• pp.51-62
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• 2016

The purpose of this paper is to study the effectiveness of a green roof by simple mathematical model. The developed model simulates a green roof during the summer. The results explain and support the claims in the literature such that effectiveness of a green roof depends on the climate condition, and on the insulation condition of the roof. If insolation can not be reduced more than 60% by the shading effects of a green roof, more active measures than green roof seem necessary. The analysis tools like presented in the paper is necessary especially to consider climate effect, to design, and also to test green roof.

• Journal of Environmental Impact Assessment
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• v.5 no.1
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• pp.95-105
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• 1996

Meteorological Joint Frequency Function required indispensably in long-term air quality prediction models were discussed for practical application in Korea. The algorithm, proposed by Turner(l964), is processed with daily solar insolation and cloudiness and height basically using Pasquill's atmospheric stability classification method. In spite of its necessity and applicability, the computer program, called STAR(STability ARray), had some significant difficulties caused from the difference in meteorological data format between that of original U.S. version and Korean's. To cope with the problems, revised STAR program for Korean users were composed of followings; applicability in any site of Korea with regard to local solar angle modification; feasibility with both of data which observed by two classes of weather service centers; and examination on output format associated with prediction models which should be used.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.12
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• pp.847-852
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• 2016

Using both EVA and POE encapsulants, we fabricated polycrystalline Si PV modules and performed a set of reliability tests of PID, DH, TC, and Complex prior to outdoor installation. The power output with temperatures and insolation as well as I-V characteristics had been monitored under outdoor environments for 18 months. In the entire period, the total power of 3,576 kWh from POE PV modules was observed larger than 3,449 kWh from EVA PV modules by 3.5%. All the PV modules showed a 5.6~9.2% drop in the conversion efficiency. As for the solar power generation, the PV modules performed through PID, TC test revealed distinct difference in between EVA and POE for which the POE PV module produced more power by +11.4% and +6.6%, respectively, as measured in the 18th month. In addition, POE was proved to protect better the solar cells under PID influence.