• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.109-112
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• 2007

In this paper, a mathematical modeling was developed to simulate 1kW class air cooled Polymer Electrolyte Membrane Fuel Cell(PEMFC) system. The proposed modeling was conducted under SIMULINK based environment. The model ing was developed based on the thermodynamic and chemical equilibrium. The objective is to design and implement the entire fuel cell system model ing including the system controller modeling. The fuel cell process and the control system modeling should have to be connected with each other simultaneously， therefore the two types of modeling influences each other when the system simulator run. The fuel cell modeling libraries are simulated using the SIMULINK under the thermodynamic and chemical equilibrium base. The PID controller application was designed and developed to test the process modeling and verify it. This the prototype development of the fuel cell system to design and test more complicate fuel cell systems, like the residential power generation system. The simulation results was compared to the real PEMFC system performance. We have achieved the reasonable accordance with the Lab test and the simulation results.

• Journal of the Korea Safety Management & Science
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• v.11 no.4
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• pp.111-118
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• 2009

In this study the real situation of apartment house in seoul is reproduced with multi-zone modeling program CONTAM2.4. This model include disinfection system which is consist of dilution, filtration, UVGI(ultra violet germicidal irradiation). It's energy consumption was also analyzed through the linked model of CONTAM and TRNSYS according to the combination of components. The comparison of total energy consumption through energy analysis revealed that adjusting the air change rate of the UVGI air sterilizer to maintain the same indoor microbe removal capability was more advantageous in terms of energy consumption.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.7
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• pp.97-104
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• 2011

This paper presents modeling and control for the emerging IGBT converter-based high-voltage direct-current system (IGBT-HVDC). This paper adds to the representation of the IGBT-HVDC system in the dq-synchronous reference frame and its decoupled control scheme. Additionally, since the IGBT-HVDC is able to actively support the grid due to its capacity to control independently active and reactive power production, a reactive power control scheme is presented in order to regulate/contribute to the voltage at a remote location by taking into account its operational state and limits. The ability of the control scheme is assessed and discussed by means of simulations using ahybrid power system, which consists of a permanent magnetic synchronous-generator (PMSG) based wind turbine, an IGBT-HVDC, and a local load.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.463-464
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• 2015

발전소마다 발전기의 효율이 달라서 출력을 조정할 때 발전소의 효율이 나빠지거나 발전기기의 고장률이 높아진다는 문제점을 가지고 있고 주파수 제어가 불가능한 신재생에너지자원이 증가하면서 주파수제어문제가 화두가 되고 있다. 이로 인해 주파수조정용 ESS(Energy Storage System: 에너지저장장치)의 필요성에 의견이 실리고 있다. 이미 주파수조정용 ESS는 미국의 여러 ISO(Integrated System Operator: 전력계통운영자)와 RTO에서 활용하고 있고 얼마 전 2015년 4월 송전사업자(한전)가 전력의 안정적 공급을 위해 ESS를 활용하여 주파수조정(F/R)에 참여를 할 수 있도록 하는 '전력시장운영규칙'을 개정하였다. 또한 정부가 신산업 육성을 위해 이와 관련한 제도를 정비해 나가려고 하고 있다. 이미 미국에서의 적용된 사례를 조사하여 국내에 주파수조정용 ESS를 적용하여 정산 시 고려할 사항을 알아보고자한다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.9
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• pp.355-360
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• 2016

Continuing to the modeling of heating load, this paper, as the second part of consecutive works, presents LS-SVM (least square support vector machine) based model of winter time apartment hot water supply load in a district heating system, so as to be used in prediction of heating energy usage. Similar, but more severely, to heating load, hot water supply load varies in highly nonlinear manner. Such nonlinearity makes analytical model of it hardly exist in the literatures. LS-SVM is known as a good modeling tool for the system, especially for the nonlinear system depended by many independent factors. We collect 26,208 data of hot water supply load over a 13-week period in winter time, from 12 heat exchangers in seven different apartments. Then part of the collected data were used to construct LS-SVM based model and the rest of those were used to test the formed model accuracy. In modeling, we first constructed the model of district heating system's hot water supply load, using the unit heating area's hot water supply load of seven apartments. Such model will be used to estimate the total hot water supply load of which the district heating system needs to provide. Then the individual apartment hot water supply load model is also formed, which can be used to predict and to control the energy consumption of the individual apartment. The results obtained show that the total hot water supply load, which will be provided by the district heating system in winter time, can be predicted within 10% in MAPE (mean absolute percentage error). Also the individual apartment models can predict the individual apartment energy consumption for hot water supply load within 10% ~ 20% in MAPE.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5893-5898
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• 2014

This paper proposes a modeling method and operating algorithm of an islanding microgrid that is composed of a Battery Energy Storage System (BESS), wind turbine and diesel generator applied in island areas. Initially, the bilateral AC/DC converter was designed for charge/discharge for frequency and voltage to be maintained within the proper ranges according to the load and weather change, and the operating method was proposed for a diesel generator to operate when power supply from the wind turbine or BESS is insufficient. The proposed modeling and controller design method of BESS was applied to a typical islanded microgrid with a wind turbine and diesel generator. The frequency and voltage was kept within the permissible ranges and the proposed method was proven to be appropriate through simulations.

• Journal of IKEEE
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• v.24 no.2
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• pp.610-618
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• 2020

This paper presents the modeling of hybrid railway vehicles with hydrogen Fuel-Cells (FCs)/battery using a rule-based algorithm. The driving power of traction system is determined with the speed-torque curve by operation area of the electric machine and the electrical systems are modeled. The demanded power of electrical systems is set with the energy management system (EMS). The consumption of hydrogen is effectively managed with the subdivided operation region depending on the state of charge (SOC). The validity of the modeling is verified using MATLAB/Simulink.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.1235-1242
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• 2013

This study deals with the BIM (Building Information Modeling)-based energy performance analysis implemented in EnergyPlus. The BIM model constructed at Revit is updated at Design Builder, adding HVAC models and converted compatibly with the EnergyPlus. We can obtain the input values about HVAC system and building environment such as HVAC system efficient, the number of air changes and energy consumption of equipment on applying GAs (Genetic algorithms). After modification about HVAC system, Optimization about HVAC system energy consumption can be analyzed. In order to maximize the building energy performance, a genetic algorithm (GA)-based optimization technique is applied to the modified HVAC models. Throughout the proposed building energy simulation, finally, the best optimized HVAC control schedule for the target building can be obtained in the form of "supply air temperature schedule". Throughout the supply air temperature schedule is applied to energy performance simulation, we obtained energy saving effect result on simulation.

• Journal of the Korean Solar Energy Society
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• v.30 no.3
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• pp.65-70
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• 2010

As for the present wind power industry, most of the computerization for monitoring and control is based on the traditional development methodology, but it is necessary to improve SCADA system since it has a phenomenon of backlog accumulation in the applicable aspect of back-data as well as in the operational aspect in the future. Especially for a system like offshore wind power where a superintendent cannot reside, it is desirable to operate a remote control system. Therefore, it is essential to establish a monitoring system with appropriate control and monitoring inevitably premised on the integrity and independence of data. As a result, a study was carried out on the modeling of offshore wind power data-centered database. In this paper, a logical data modeling method was proposed and designed to establish the database of offshore wind power. In order for designing the logical data modeling of an offshore wind power system, this study carried out an analysis of design elements for the database of offshore wind power and described considerations and problems as well. Through a comparative analysis of the final database of the newly-designed off-shore wind power system against the existing SCADA System, this study proposed a new direction to bring about progress toward a smart wind power system, showing a possibility of a service-oriented smart wind power system, such as future prediction, hindrance-cause examination and fault analyses, through the database integrating various control signals, geographical information and data about surrounding environments.

• Journal of the Korean Society for Railway
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• v.3 no.4
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• pp.177-184
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• 2000

In this paper, a HVAC controller which has a bilinear system is designed to control the air temperature in building room and a saving of energy on the HVAC system. For modeling of the HVAC bilinear system, AHU(Air Handling Unit) is modeled on the control of inside-outside air flow using three dampers in a duct. A heat exchanger and the single room are also modeled by the energy conservation law. Under the modeling of the HVAC bilinear system, the control's law of the bilinear HVAC system is derived by Lyapunov's non-linear theory and Deress's the linear feedback laws for bilinear system. In this paper it was proved that the controller of the HVAC bilinear system is able to control the air temperature with a disturbance in order to get a target of temperature in the building room by the computer simulation when the control inputs regulate the air flow rate and a capacity of the heat exchanger.