• Journal of Advanced Marine Engineering and Technology
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• v.29 no.3
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• pp.319-324
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• 2005

This paper reports the performance of Wind-PV(Photovoltaic) hybrid system. The output power of PV is affected by the environmental factors such as solar radiation and cell temperature. Also, the output power of wind system is generated with wind power. Integration of Wind and PV resources, which are generally complementary, usually reduce the capacity of the battery. This paper includes discussion on system reliability, power quality and effects of the randomness of the wind and the solar radiation on system design.

• Journal of Astronomy and Space Sciences
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• v.27 no.3
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• pp.253-262
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• 2010

The electrical power system (EPS) of Korean satellites in low-earth-orbit is designed to achieve energy balance based on a one-orbit mission scenario. This means that the battery has to be fully charged at the end of a one-orbit mission. To provide the maximum solar array (SA) power generation, the peak power tracking (PPT) method has been developed for a spacecraft power system. The PPT is operated by a software algorithm, which tracks the peak power of the SA and ensures the battery is fully charged in one orbit. The EPS should be designed to avoid the stress of electronics in order to handle the main bus power from the SA power. This paper summarizes the results of energy balance to achieve optimal power sizing and the actual trend analysis of EPS performance in orbit. It describes the results of required power for the satellite operation in the worst power conditions at the end-of-life, the methods and input data used in the energy balance, and the case study of energy balance analyses for the normal operation in orbit. Both 10:35 AM and 10:50 AM crossing times are considered, so the power performance in each case is analyzed with the satellite roll maneuver according to the payload operation concept. In addition, the data transmission to the Korea Ground Station during eclipse is investigated at the local-time-ascending-node of 11:00 AM to assess the greatest battery depth-of-discharge in normal operation.

• Fire Science and Engineering
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• v.14 no.1
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• pp.22-26
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• 2000

Emergency lamp is installation usage on an emergency situation or firing. It's an offer at least of brightness. It's lighting to common source usually. It's transferred to reserve battery on power stoppage. This emergency lamp is lighted from solar cell system. The solar cell should be operated at the maximum power point. This paper proposes the new control method that half-bridge inverter using the solar cell can operate emergency lamp.

• Journal of Aerospace System Engineering
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• v.8 no.4
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• pp.32-38
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• 2014

Sufficient energy charging during a day is essential for a solar-powered long-endurance aircraft. Variations of flight path that is superior to a basic circle path are sought in this study for more efficient charging. Flight path associated with roll and pitch attitudes are investigated. It seems that the pitch angle can play more important role than the roll angle for the solar charging efficiency. Thus, more energy charging is observed when the entire flight path is tilted toward the direction of the sun.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.6_1
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• pp.1001-1010
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• 2023

To solve the problem that photovoltaic panels can not harvest electrical energy at a cloudy day and night, a floating solar thermoelectric generator (FSTEG, hereafter) is studied. The FSTEG is consisted of a dome shaped Fresnel lens to condense solar energy, a thermoelectric module connected with a heat sink to keep temperature difference, a floating system simulating a wavy ocean and an electrical circuit for energy storage. The dome shaped Fresnel lens was designed to have 29 prisms and its optical performance was evaluated outdoors under natural sunlight. Four thermoelectric modules were electrically connected and its performance was evaluated. The generated energy w as stored in a Li-ion battery by using a DC-DC step-up converter. For the application of ocean environment, the FSTEG was covered by the dome shaped Fresnel lens and sealed to float in a water-filled reservoir. The harvested energy shows a potential and a method that the FSTEG is suitable for the energy generation in the ocean environment.

• Journal of Electrical Engineering and Technology
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• v.13 no.2
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• pp.742-751
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• 2018

Electric vehicles (EV) are emerging as the future transportation vehicle reflecting their potential safe environmental advantages. Vehicle to Grid (V2G) system describes the hybrid system in which the EV can communicate with the utility grid and the energy flows with insignificant effect between the utility grid and the EV. The paper presents an optimal power control and energy management strategy for Plug-In Electric Vehicle (PEV) charging stations using Wind-PV-FC-Battery renewable energy sources. The energy management optimization is structured and solved using Multi-Objective Particle Swarm Optimization (MOPSO) to determine and distribute at each time step the charging power among all accessible vehicles. The Model-Based Predictive (MPC) control strategy is used to plan PEV charging energy to increase the utilization of the wind, the FC and solar energy, decrease power taken from the power grid, and fulfil the charging power requirement of all vehicles. Desired features for EV battery chargers such as the near unity power factor with negligible harmonics for the ac source, well-regulated charging current for the battery, maximum output power, high efficiency, and high reliability are fully confirmed by the proposed solution.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.2
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• pp.150-157
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• 2014

Li-Ion battery is used in the most satellites now due to advantages such as weight, thermal dissipation and self discharge compared to the previous generations of electrochemical batteries. The performance analysis model of the Li-Ion battery is needed to aid the design of new satellite electrical power subsystem. This paper develops the performance analysis model of the Li-Ion battery to apply to the electrical power subsystem design and energy balance analysis on geostationary orbit. The analysis model receives the satellite bus power, solar array power and battery temperature and gives the battery voltage, charge and discharge currents, taper index, state of charge and power dissipation. The results from the performance analysis are compared and analyzed with the flight data to verify the model. The compared results show satisfactory without significant difference with the flight data.

• Journal of Advanced Navigation Technology
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• v.20 no.1
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• pp.86-92
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• 2016

Recently, solar module is installed in crowded areas to offers services so that people can charge their smartphones or tablets. However, the burden in terms of cost is high to install in areas where utilization ratio is low and installation is difficult in limited spaces. In this paper, a system for collecting and providing the optical power is proposed from the analysis about the person that receives service in each area using the real-time data provided by the state and collected from the actual environment as well as considering the waiting time and the solar charging time in different environments. As a result, This study shows that charge was not delayed since collecting power exceeds charging power. Smartphone was fully charged in ninety-five minutes. we confirmed that with one smartphone, it can be charged a approximately fifty percent of the battery in between ten to twenty minutes, with multiple units they can be charged a approximately twenty percent of the battery in between ten to twenty minutes.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.2
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• pp.137-142
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• 2021

A Photovoltaic power streetlight is a system that uses solar energy to charge a secondary battery and then uses it for night lighting through a lamp, and can be configured as a standalone or grid-connected type by installing an LED streetlight at the load end. The energy generated through the solar cell module can be charged to the secondary battery through the charge/discharge control device, and then the LED street light can be turned on and off by comparing the power generation voltage and the charging voltage according to the monitoring of solar radiation, or by setting a specific time after sunset or sunrise. Based on these contents, this paper designed and manufactured a simulated solar power streetlight for education using new and renewable energy utilization and storage functions. Using these educational equipment, students can 1) understand the flow of energy change using renewable energy including sunlight as electric energy, 2) understand new and renewable energy, and cultivate basic design and manufacturing application power of related products, 3) The use of new and renewable energy through power conversion and strengthening of practical training and analysis through hardware production can be instilled.

• Proceedings of the KIPE Conference
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• 2013.11a
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• pp.117-118
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• 2013

Recent global warming to the promotion of electric vehicles (EV), plug-in hybrid (PEV), including the next generation of cars and solar power, wind power and other renewable energy, and next-generation power grid (smart grid) are getting attention. In addition, the system utilizes the battery life in the industry and the convenience of a variety of social systems, economics, environmental impact, and the inherent potential to change significantly, and you can not walk into a next-generation industrial strategy and the need increases more and more present, and its early commercialization In order to do this, as well as a key energy source, the battery charger for charging efficiency technologies is essential. In this paper, fast charge multiple battery modules and optional modules that can charge distribution charge will be introduced.