• 태양에너지
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• 제18권3호
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• pp.71-80
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• 1998

In thermal energy storage system, energy collected from many types of heat source is stored in a storage tank and then supply to load for demand. Lately, practical use of thermal energy storage system and attention to essential use of energy have been increased. From this point of view, especially, a study about the energy extraction process from a storage tank is necessary. So in this study, useful rate of hot water and hot water extraction efficiency was analysed respect to dynamic and geometric parameters dominating the hot water extraction process.

• 한국전자통신학회논문지
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• 제10권6호
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• pp.691-698
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• 2015

최근, 전력산업에서는 지구 온난화에 대비하여 에너지 이용 효율 극대화하기 위한 방안으로 초전도 에너지 저장 장치에 큰 관심을 가지고 있다. 초전도 에너지 저장장치는 비 첨두시에 대량의 전기에너지를 손실 없이 자계 또는 운동 에너지의 형태로 저장하였다가 첨두시에 이를 다시 전기에너지로 변환하여 사용함으로서 피크부하의 균등화 및 순간정전 보상을 실현, 전기 에너지 이용 효율의 극대화를 기할 수 있다. 따라서 본 연구에서는 초전도 에너지 저장기술에 대한 개념, 연구개발 현황 및 그 적용 사례 등을 조사, 분석하여, 전력계통 적용 기반기술을 확립하고자 한다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.754-760
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• 2011

In the DC traction system, a large load current of electric railcar leads to a voltage drop when a vehicle starts, and the regenerative power generated by brake system increases the catenary voltage. To minimize the voltage fluctuation during the train operation and make use of the regenerative power, several types of energy storage systems are being studied. The energy storage system that is being recently introduced consists of the supercapacitors for energy storage and the bi-direction DC/DC converter for charge/discharge control. The efficiency of the energy storage system depends on the train operation pattern. In this paper, the operation efficiency of the energy storage system was quantitatively analyzed via simulation study taking consideration of the train operation patterns. The simulation was conducted changing the headway of trains with the energy storage system that uses the bi-direction DC/DC converter and supercapacitor. The simulation results showed that the operation efficiency of the energy storage system increases as the headway increase.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 F
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• pp.1924-1926
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• 1997

With the development of power electronics, many new energy storage systems such as the superconducting magnetic energy storage, the flywheel energy storage, and the capacitive energy storage, etc. are being intensively studied recently in order to replace battery in some special applications, Among these innovative energy storage systems, the flywheel system exhibits some unique features such as high power density, easy maintenance and longer lifetime. This paper introduces the novel flywheel energy storage system. Operation and features of the system are illustrated and verified on a 6kVA, 20kHz IPM based experimental circuit for O/A application. The Halbach Array Motor is selected of the design of the three phase motor/generator for the flywheel energy storage system.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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• pp.534-538
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• 2001

Energy storage devices with high energy density as well as high power density are expected to be developed from the point of view of compensation of fluctuating load and generated power by distributed generations such as wind turbines, photovoltaic cells and so on. SMES (Superconducting Magnetic Energy Storage) has higher power density than other energy storage methods, and secondary batteries have higher energy density than SMES. The hybrid energy storage device using SMES and secondary batteries is proposed as the energy storage method with higher power and energy density, the sharing method of power reference value for each storage device, simulation and experimental results are presented.

• Nuclear Engineering and Technology
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• 제53권8호
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• pp.2427-2444
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• 2021

The lack of plant-side energy storage analysis to support nuclear power plants (NPP), has setup this research endeavor to understand the characteristics and role of specific storage technologies and the integration to an NPP. The paper provides a qualitative review of a wide range of configurations for integrating the energy storage system (ESS) to an operating NPP with pressurized water reactor (PWR). The role of ESS technologies most suitable for large-scale storage are evaluated, including thermal energy storage, compressed gas energy storage, and liquid air energy storage. The methods of integration to the NPP steam cycle are introduced and categorized as electrical, mechanical, and thermal, with a review on developments in the integration of ESS with an operating PWR. By adopting simplified off-design modeling for the steam turbines and heat exchangers, the results show the performance of the PWR steam cycle changes with respect to steam bypass rate for thermal and mechanical storage integration options. Analysis of the integrated system characteristics of proposed concepts for three different ESS suggests that certain storage technologies could support steady operation of an NPP. After having reviewed what have been accomplished through the years, the research team presents a list of possible future works.

• Korean Journal of Chemical Engineering
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• 제36권1호
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• pp.12-20
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• 2019

An energy storage system consisting of a battery and a power-to-methanol (PtM) unit was investigated to develop an energy storage system for renewable energy systems. A nonlinear programming model was established to optimize the energy storage system. The optimal installation capacities of the battery and power-to-methanol units were determined to minimize the cost of the energy system. The cost from a renewable energy system was assessed for four configurations, with or without energy storage units, of the battery and the power-to-methanol unit. The proposed model was applied to the modified electricity supply and demand based on published data. The results show that value-adding units, such as PtM, need be included to build a stable renewable energy system. This work will significantly contribute to the advancement of electricity supply and demand management and to the establishment of a nationwide policy for renewable energy storage.

• 태양에너지
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• 제17권1호
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• pp.79-91
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• 1997

Thermal energy storage system used a storage tank is a reasonable method to solve energy problem. In thermal energy storage system, energy collected from many types of heat source is stored in a storage tank and then supply to load at the time is in demand. In this study, flow characteristics and storage efficiency were analysed by using a insulated raft in longterm hot water storage system. From the experiment it is found that insulated raft has a important role in longterm hot water storage system and storage efficiency can be obtained to 96% using inletport type and insulated raft together.

• 공업화학
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• 제24권4호
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• pp.344-349
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• 2013

에너지 저장 시스템(energy storage system, ESS)은 발전설비에서 생산된 전력에너지를 저장하여 필요한 시점에 사용할 수 있도록 전기에너지를 화학적으로 저장하는 체계이다. 따라서 에너지 저장 시스템은 에너지 이용 효율향상, 전력공급 시스템의 안정화에 기여할 뿐 아니라, 이산화탄소의 감축 및 화석연료의 고갈문제에 직접 대응할 수 있게 한다. 이차전지인 납 축전지는 현재까지 가장 기술적으로 안정되어 있고, 경제적이며, 신뢰성이 있는 축전지 중 하나이다. 이에 본 연구에서는 납 축전지를 적용한 에너지 저장 시스템의 국내외 실증사례를 조사하여 사례별로 정리하여 관련연구에 참고하고자 한다.

• 한국태양에너지학회 논문집
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• 제26권4호
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• pp.39-45
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• 2006

The decrease in the summer peak electric load in our country is very important. The government has arranged and implemented a lot of support policies and statutes to decrease the peak electric load. And the ice thermal energy storage system is known as one of the alternatives. The purpose of this paper is to evaluate the efficiency and thermal characteristics of the closed ice thermal energy storage system using screw capsules. The measured thermal energy storage density is about 18.4 USRT-h/m3 (=232.9 MJ/m3), which is higher than 13.0 USRT-h/m3 (=164.6 MJ/m3), a low criterion of normal performance. And The efficiency of the discharging process and the total energy utilization is 96.2% and 2028.4 kcal/kWh respectively.