• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.285-287
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• 2008

This paper represents the electric power load leveling effect of the Light Control System(LCS). The lighting of typical mid-large commercial buildings is the major factor of daytime electric power consumption. Since the national peak power demand occurs in between 11:00 and 16:00, the dimming control of light can contribute the decrease of the power demand We will discuss the load leveling effect of dimming control with LCS.

• Journal of Electrical Engineering and Technology
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• v.12 no.1
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• pp.1-10
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• 2017

With the current global need for eco-friendly energies, the large scale use of Electric Vehicles (EVs) is predicted. However, the need to frequently charge EVs to an electrical power system involves risks such as rapid increase of demand power. Therefore, in this paper, we propose a practical smart EV charging scheme considering a Time-of-Use (ToU) price to prevent the rapid increase of demand power and provide load leveling function. For a more practical analysis, we conduct simulations based on the actual distribution system and driving patterns in the Republic of Korea. Results show that the proposed method provides a proper load leveling function while preventing a rapid increase of demand power of the system.

• International Journal of Automotive Technology
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• v.6 no.4
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• pp.429-436
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• 2005

In this paper, operation algorithms are evaluated for a fuel cell hybrid electric vehicle (FCHEV). Power assist, load leveling and equivalent fuel algorithm are proposed and implemented in the FCHEV performance simulator. It is found from the simulation results that the load leveling algorithm shows poor fuel economy due to the system charge and discharge efficiency. In the power assist and equivalent fuel algorithm, the fuel cell stack is operated in a relatively better efficiency region owing to the battery power assist, which provides the improved fuel economy.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.2
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• pp.264-268
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• 2016

Recently, various energy efficiency optimization activities are ongoing globally by integrating conventional grids with ICT (Information and Communication Technology). In this sense, various smart grid projects, which power suppliers and consumers exchange useful informations bilaterally in real time, have been being carried out. The electric vehicle diffusion program is one of the projects and it has been spotlighted because it could resolve green gas problem, fuel economy and tightening environmental regulations. In this paper, the economics of V2G system which consists of electric vehicles and the charging infrastructure is evaluated comparing electric vehicles for V2G with common electric vehicles. Additional benefits of V2G are analyzed in the viewpoint of load leveling, frequency regulation and operation reserve. To find this benefit, electricity sales is modeled mathematically considering depth of discharge, maximum capacity reduction, etc. Benefit and cost analysis methods with the modeling are proposed to decide whether the introduction of V2G systems. Additionally, the methods will contribute to derive the future production and the unit cost of electric vehicle and battery and to get the technical and economic analysis.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.15 no.1
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• pp.9-17
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• 2019

Reducing global warming potential has become important, and as one of those methods for reducing it, economic evaluation by applying ice thermal storage air conditioning system was performed. The floor area and height of the subject building was assumed $5,000m^2$ and 20 m. Absorption chillerheater system and air source heat pump system was used for comparing to the subject system, and payback period method was used to perform economic evaluation. Although the running cost of ice thermal storage system is reduced compared to two systems, the ratio is not significant compared to the increase of initial construction expenses, and payback period was calculated to be about 7.7 and 79.3 years. However, the heat storage system should be approached from the viewpoint of long term rather than the economic standard in the present standard.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.538-539
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• 2014

The development of smart grid technologies will enable enhanced utilization of electric vehicles(EV) as portable energy storage devices which can provide power system-wide. Because significant increase of EV in the near future, V2G(Vehicle-to-Grid) system will soon become a reality. This paper presents the optimal method of a battery lifetime depending on depth of discharge(DOD) considering load leveling.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1995.05a
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• pp.173-178
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• 1995

Hoop Energy Storage System(HESS) for electric power utility were discussed laying primary stress on the diurnal load leveling of Korean electric power system. A number of potential storage technologies are outlined and possibility for real application of HESS was suggested. Primary system variables were determined on the basis of state of electric power demand-supply of 1994. As a prerequisite technology for HESS, noncontacting support using magnetic pressure and high power conversion were discussed.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.379-382
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• 2008

This paper gives the support method of DSM program(power load leveling for heating and cooling facilities on building). As the national power peak load increases recently, the peak load reduction is needed. So we studied about remote controlling of power load from heating/cooling facilities on building during peak times. To adopt new DSM program, it is very important to design DSM customer supporting system. So in this paper, we dealt with the result of customer survey, and the DSM potential regarding heating/cooling facilities on building. In conclusion, the peak reduction program of heating/cooling facilities is very important and the incentive of customer should be consist of two incentive types as an installation and power reduction.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.6
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• pp.783-790
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• 2012

Electric Vehicles(EVs) and Plug-in Hybrid Electric Vehicles(PHEVs) which have the grid connection capability, represent an important power system issue of charging demands. Analyzing impacts EVs charging demands of the power system such as increased peak demands, developed by means of modeling a stochastic distribution of charging and a demand dispatch calculation. Optimization processes proposed to determine optimal demand distribution portions so that charging costs and demand can possibly be managed. In order to solve the problems due to increasing charging demand at the peak time, alternative electricity rate such as Time-of-Use(TOU) rate has been in effect since last year. The TOU rate would in practice change the tendencies of charging time at the peak time. Nevertheless, since it focus only minimizing costs of charging from owners of the EVs, loads would be concentrated at times which have a lowest charging rate and would form a new peak load. The purpose of this paper is that to suggest a scenario of load leveling for a power system operator side. In case study results, the vehicles as regular load with time constraints, battery charging patterns and changed daily demand in the charging areas are investigated and optimization results are analyzed regarding cost and operation aspects by determining optimal demand distribution portions.

• Proceedings of the KIEE Conference
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• 2005.04a
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• pp.265-267
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• 2005

In this paper presents residential PV system based on battery energy storage system for managing the electric power, a pattern of daily operation considering the load characteristic of the house, the generation characteristic of PV power, and utility power leveling. For apply to control algorithm, we consider the load on monthly power consumption trend and daily usage pattern. As for the control of the proposed system, to increase the conversion efficiency of the PV power, bidirectional converter is used for MPPT and SVPWM inverter. An experimental system is implemented, and some experimental results are provided to demonstrate the effectiveness of the proposed system.