• Journal of Electrical Engineering and Technology
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• v.12 no.5
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• pp.1916-1924
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• 2017

Fossil oil, as the main energy of transportation, is destined to be exhausted. The electrification of transportation is a sustainable solution to the energy crisis, since electric power could be acquired from the inexhaustible sun, wind and water. Among all the problems that hinder the development of Electric Vehicle (EV) industry, charging issue might be the most prominent one. In this paper, the service process of a charging station with Battery Energy Storage System (BESS) is analyzed by means of $Cram{\acute{e}}r$ - Lundberg model which has been intensively utilized in ruin theory. The service quality is proposed in two dimensions: the service efficiency and the service reliability. The arrival rate and State of Charge (SOC) upon arrival are derived from 2009 National Household Travel Survey (NHTS). The simulations are performed to show how the service quality is determined by the system parameters such as the number of servers, the service rate, the initial capacity, the charge rate and the maximum waiting time. At last, the economic analysis of the system is conducted and the best combination of the system parameters are given.

• Journal of Electrical Engineering and Technology
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• v.12 no.5
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• pp.1789-1797
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• 2017

It is necessary to charge electric vehicles in order to drive them. Thus, it is essential to have electric vehicle charging facilities in place. In the case of a household battery charger, the power similar to that consumed by a household with a basic contract power of 3kW is consumed. In addition, many consumers who own an electric vehicle will charge their vehicles at the same time. The simultaneous charging of electric vehicles will cause the load to increase, which then will lead to the imbalance of supply and demand in the distribution system. Thus, a smart charging scheme for electric vehicles is an essential element. In this paper, simulated conditions were set up using real data relating to Korea in order to design a smart charging technique suitable for the actual situation. The simulated conditions were used to present a smart charging technique for electric vehicles that disperses electric vehicles being charged simultaneously. The EVs and Smart Charging Technique are modeled using the Electro Magnetic Transients Program (EMTP).

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.11
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• pp.1793-1799
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• 2016

As one of the main trends in global industries is eco-friendly energy, the interest on Electric Vehicle(EV) has been increased. However, if large amount of EVs start to charging, it could cause rapid increase in demand power of the power system. To guarantee stable operation of the power system, those unpredictable power consume should be mitigated. In this paper, therefore, we propose a practical smart EVs charging scheme to prevent the rapid increase of the demand power and also provide load flattening function. For that we considered Time-of-Use(ToU) price and actual data such as driving pattern and parameters of distribution system. Simulation results show that the proposed method provides proper load flattening function while preventing the rapid increase of the demand power of the power system.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.220-221
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• 2011

본 논문에서는 EV (Electric Vehicle)용 충전 인프라 구축을 위한 BESS (Battery Energy Storage System)의 용량을 산정한다. 이를 위해 실제 대형마트의 데이터를 이용하여 EV용 충전 인프라가 구축될 경우의 추가수요전력량을 산출하고 현재의 전력수급량을 바탕으로 EV 보급시의 최대수요전력량을 예측한다. 이들을 계약전력과 비교하여 필요전력량을 분석하고 이를 바탕으로 충전 인프라에 이용되는 BESS의 용량을 산정한다.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.5
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• pp.105-110
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• 2020

The global battery market is rapidly growing due to the development of vehicles(EV) and wireless electronic products. In particular logistics robots, which hielp to produce EVs, have attracted much interest in research in Korea Because logistics sites and factories operate continuously for 24 hours, the technology that can dramatically increase the operation time of the logistics equipment is rapidly developing, and various high-level technologies are required for the batteries used in. for example, logistics robots. These required technologies include those that enable rapid battery charging as well wireless charging to charge batteries while moving. The development of these technologies, however, result in increasing explosions and topical accidents involving rapid charging batteries These accidents due to the thermal shock caused by the heat generated during the charging of the battery cell. In this study, a performance evaluation of a heat dissipation design using infrared thermal imaging was performed on an energy storage systrm(Ess) applied with an internal heat conduction cooling method using a heating plate.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1240-1241
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• 2011

이 논문은 LS전선, 서울 메트로, 철도기술연구원(KRRI)이 공동으로 연구한 '도시철도 연계 EV 충전 시스템' 프로젝트와 LS전선, 환경공단이 공동 개발한 '전기 자동차 충전 인프라 구축 사업'을 바탕으로 내용을 구성 하였다. 전기 자동차 충전 인프라 시스템 구축은 크게 3가지 이슈 -전력 연계, 충전 시설, 충전기 운영 통신 시스템-가 있다. 전기 자동차 충전 시스템을 철도 전력 인프라망을 연계했을 때 얻을 수 있는 이점들, 충전 인프라 운영 시스템에 대한 실증 내용을 논하였으며 추가적으로 향후 계획도 포함되어 있다.

• KEPCO Journal on Electric Power and Energy
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• v.7 no.2
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• pp.329-333
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• 2021

V2G (Vehicle to Grid) technology for an EV (Electric Vehicle) has been assumed as so promising in a near future for its useful energy resource concept but still yet to be developed around the world for specific service purposes through various R&BD projects. Basically, V2G returns power stored in vehicle at a cheaper or unused time to the grid at more expensive or highly peaked time, and is accordingly supposed to provide such roles like peak shaving or load levelling according to customer load curve, frequency regulation or ancillary reserves, and balancing power fluctuation to grid from the weather-sensitive renewable sources like wind or solar generations. However, it has recently been debated over its prominent usage as diffusing EVs and the required charging/discharging infrastructure, partially for its addition of EV ownership costs with more frequent charging/discharging events and user inconvenience with a relative long-time participation in the previously engaged V2G program. This study suggests that a Korean DR (Demand Response) service integrated V2G system especially based upon a dynamic charge/pause/discharge scheme newly proposed to ISO/IEC 15118 rev. 2 can deal with these concerns with more profitable business model, while fully making up for the additional component (ex. battery) and service costs. It also indicates that the optimum economic, environmental, and grid impacts can be simulated for this V2G-DR service particularly designed for EV aggregators (V2G service providers) by proposing a specific V2G engagement program for the mediated DR service providers and the distributed EV owners.

• Journal of Internet of Things and Convergence
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• v.10 no.1
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• pp.1-6
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• 2024

In order to increase the use of electric vehicles (EVs) and minimize grid strain, microgrid using renewable energy must take an important role. Microgrid may use fossil fuels such as small diesel power, but in many cases, they can be supplied with energy from renewable energy, which is an eco-friendly energy source. However, renewable energy such as solar and wind power have variable output characteristics. Therefore, in order to meet the charging and discharging energy demands of electric vehicles and at the same time supply load power stably, it is necessary to review the configuration of electric vehicle charging infrastructure that utilizes diesel power or electric vehicle-to-grid (V2G) as a parallel energy source in the microgrid. Against this background, this study modelized a microgrid that can stably supply power to loads using solar power, wind power, diesel power, and V2G. The proposed microgrid uses solar power and wind power generation as the primary supply energy source to respond to power demand, and determines the operation type of the load's electric vehicles and the rotation speed of the load synchronous machine to provide stable power from diesel power for insufficient generations. In order to verify the system performance of the proposed model, we studied the stable operation plan of the microgrid by simulating it with MATLAB /Simulink.

• Journal of Internet Computing and Services
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• v.20 no.2
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• pp.51-59
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• 2019

In this paper, we analyzed the relationship between charging operation system and electricity charges connected with charging infrastructure among data of many demonstration projects focused on electric vehicles recently. At this point in time, due to the rapid increase in demand for the electric charging infrastructure that will take place in the future, we can prepare for an upcoming era in the sense of forecasting the demand value. At the same time, demonstrating and modeling optimized system modeling centering on sites is a prerequisite. The modeling based on the existing small - scale simulation and the design of the operating system are based on the data linkage analysis. In this paper, we implemented a new optimized system modeling and introduced it as a standard format to analyze time - dependent time - divisional data for each vehicle and user in each point and node. In order to verify the efficiency of the optimization based on the data linkage analysis for the actual implemented electric car charging infrastructure and operation system.

• Journal of the Korea Society for Simulation
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• v.25 no.4
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• pp.93-108
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• 2016

Electric vehicle car sharing (EV-sharing) system is noted as an eco-friendly system of transportation in global warming crisis and has been practically implemented in some cities around the world. However, methodologies to find the efficient operation conditions of EV-sharing systems reflecting a typical characteristic 'charging' have not been fully investigated yet. In the paper a generalized model has been developed to identify optimal level of infrastructure for EV-sharing system which provides the optimum operation efficiency under service level constraints. From the simulation analysis based on the developed model the relationships between the operational variables to describe EV-sharing system have been identified and optimal capacity to maximize the operational efficiency have been found. From the analysis of simulation results it has been found that increases in the number of vehicles and chargers improve the service level until certain value beyond which increasing rate and the efficiency have been reduced. From the cost-revenue analysis the optimal numbers of vehicles and chargers have been identified which maximizes the annual operational profit.