• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.4
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• pp.927-933
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• 2014

Ship Power Management System(SPMS) based on Communication Network(CN) is one of the most significant factor for a safe voyage. Therefore, most of the vessels are using greater capacity generator than necessary to prevent pulsating load for safety purposes. However, It provokes low-load damage and reduces generator efficiency that using large capacity generator. Accordingly, in this paper propose hybrid power system for prevent damage of pulse load. Simulation using NI's LabVIEW was conducted for the design of the power system based on actual navigation data of the ship. Also, propose applying methods for hybrid power system in connection with the auxiliary power system for safe navigation.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.5
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• pp.713-718
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• 2014

DC urban railway power system consists of DC power network and AC power network. The DC power network supplies electric power to railway vehicles and the AC power network supplies electric power to station electric equipment. Recently, because of power consumption reduction and peak load shaving, intelligent measurement of regenerative energy and renewable energy adapted on DC urban railway is required. For this reason, DC smart metering system for DC power network shall be developed. Therefore, in this paper, DC voltage sensor, current sensor, and DC smart meter were developed and evaluated by performance test. DC voltage sensor was developed for measuring standard voltage range of DC urban railway, and DC current sensor was developed as hall effect split core type in order to install in existing system. DC smart meter possesses function of general intelligent electric power meter, such as measuring electricity and wireless communication etc. And, DC voltage sensor showed average 0.17% of measuring error for 2,000V/50mA, and current sensor showed average 0.21% of measuring error for ${\pm}2,000V/{\pm}4V$ in performance test. Also DC smart meter showed maximum 0.92% of measuring error for output of voltage sensor and current sensor. In similar environment for real DC power network, measuring error rate was under 0.5%. In conclusion, accuracy of DC smart metering system was confirmed by performance test, and more detailed performance will be verified by further real operation DC urban railway line test.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.1
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• pp.24-31
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• 2012

This study is designed to predict the overall electric power load, to apply the method of time sharing and to reduce simultaneous load factor of electric power when authorized by user entering demand plans and using schedules into the user's interface for a certain period of time. This is about smart grid, which reduces electric power load through simultaneous load factor of electric power reduction system supervision agent. Also, this study has the following characteristics. First, it is the user interface which enables authorized users to enter and send/receive such data as demand plan and using schedule for a certain period of time. Second, it is the database server, which collects, classifies, analyzes, saves and manages demand forecast data for a certain period of time. Third, is the simultaneous load factor of electric power control agent, which controls usage of electric power by getting control signal, which is intended to reduce the simultaneous load factor of electric power by the use of the time sharing control system, form the user interface, which also integrate and compare the data which were gained from the interface and the demand forecast data of the certain period of time.

• Nuclear Engineering and Technology
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• v.50 no.1
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• pp.203-210
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• 2018

As the modernization of the nuclear instrumentation system progresses, research reactors have adopted digital wide-range neutron power measurement (DWRNPM) systems. These systems typically monitor the neutron flux across a range of over 10 decades. Because neutron detectors only measure the local neutron flux at their position, the local neutron flux must be converted to total reactor power through calibration, which involves mapping the local neutron flux level to a reference reactor power. Conventionally, the neutron power range is divided into smaller subranges because the neutron detector signal characteristics and the reference reactor power estimation methods are different for each subrange. Therefore, many factors should be considered when preparing the calibration procedure for DWRNPM channels. The main purpose of this work is to serve as a reference for performing the calibration of DWRNPM systems in research reactors. This work provides a comprehensive overview of the calibration of DWRNPM channels by describing the configuration of the DWRNPM system and by summarizing the theories of operation and the reference power estimation methods with their associated calibration procedure. The calibration procedure was actually performed during the commissioning of an open-pool type research reactor, and the results and experience are documented herein.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.5
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• pp.82-91
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• 2014

The combined generator system by integrating several renewable energy sources can share the electrical infrastructure and therefore have the advantage of constructing not only the transmission system but also the power conversion system. Among the various combined renewable system, the wind power and wave power has a high possibility of future growth due to the economic feasibility in offshore environment. This kind of large-scale combined systems might be follow the determination by the transmission system operator's directions and control the output profile by focusing at PCC. However, both renewable energies are depend on the unpredictable environmental variation; it is needed to do the compensation devices. In this paper, the ESS compensation plan is proposed to do output determination of the combined generator system by paying attention to active power of utility grid with the analysis of the controllable elements of the wind and wave power generator. The improvement of the new application technique of the combined system is confirmed through using the PSCAD/EMTDC. The entire simulation process was designed by adopting the active power control according to the reference signal of TSO.

• Journal of Power System Engineering
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• v.21 no.4
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• pp.84-93
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• 2017

This study was carried out to improve the electric power consumption of HVAC in the blow mold machine(BMM) and work environment. The experiment was conducted with the simulated HVAC system of 1/15 of the actual BMM. The temperature of main facility and two preheaters was fixed at 200 and $60^{\circ}C$ respectively in all test conditions. The measured points of temperature were chosen as critical locations considering the work environment. The tendency of temperature distributions decreases as the duct was closed to the main facility. The reduction rate of power consumption of HVAC increases up to 32.3% when both duct and cooling systems are operated. Also the efficiency of HVAC is improved about 9% through the modified design of duct system. It notes that the electric power consumption of HVAC can be reduced by the optimum design and operating condition of duct and cooling system.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.37-40
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• 2014

Capturing the carbon dioxide emitted from coal-fired power plants will be necessary if targeted reduction in carbon emissions is to be achieved. Modelling and simulation are the base for optimal operation and control in thermal power plant and also play an important role in energy savings. This study aims to analyze the performance of supercritical coal fired power plant through steady and dynamic simulation using a commercial software gCCS. A whole power plant has been modeled and validated with design data of 500 MWe power plant, base and part load operations of the plant were also evaluated, consequently it had been proven that the simulated result had a good agreement with actual operating data. In addition, the effect of co-firng on the plant efficiency and flue gases were investigated using gCCS simulator.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.307-308
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• 2008

This paper presents the effects of operating Backup Dispatch Center as a System Dispatch Center(SDC). SDC operates the 154kV transmission lines outside of Seoul metropolitan area, and acts as the backup dispatch center in case of central dispatch center's failure. With SDC, it became possible not only to divide operation of Korean transmission lines to separate control centers according to voltage and region, but to clear faults faster and more accurately. It has paved the way to improve power system reliability and advance the power system operation in general.

• KEPCO Journal on Electric Power and Energy
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• v.1 no.1
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• pp.105-108
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• 2015

A digital Governor (GOV) has been developed for being used for a Francis hydro turbine, and the validity of the GOV has been tested. As for the hardware system for the GOV, we purchased a basic digital control system that already had proven its reliability in the power industry. We developed a set of new GOV software and integrated it with the hardware system, and finally verified the performance of the whole GOV system. For the human-machine interface (HMI), we configured and implemented appropriate graphic interfaces for the turbine operations. This paper describes the major GOV control functions, approaches we took in developing the GOV control logics, and the validity tests and the results.

• Transactions of the Korean hydrogen and new energy society
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• v.20 no.5
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• pp.384-389
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• 2009

KEPRI (Korea Electric Power Research Institute) has studied planar type solid oxide fuel cell (SOFC) stacks using anode-supported cells and kW class co-generation systems for residential power generation. In this work, a 1 kW SOFC system consisted of a hot box part, a cold BOP (balance of plant) part, and a hot water reservoir. The hot box part contained a SOFC stack made up of 48 cells, a fuel reformer, a catalytic combustor, and heat exchangers. Thermal management and insulation system were especially designed for self-sustainable operation in that system. A cold BOP part was composed of blowers, pumps, a water trap, and system control units. When the 1 kW SOFC stack was tested using hydrogen at $750^{\circ}C$, the stack power was about $1.2\;kW_e$ at 30 A and $1.6\;kW_e$ at 50 A. Turning off an electric furnace, the SOFC system was operated using hydrogen and city gas without any external heat source. Under self-sustainable operation conditions, the stack power was about $1.3\;kW_e$ with hydrogen and $1.2\;kW_e$ with city gas respectively. The system also recuperated heat of about $1.1\;kW_{th}$ by making hot water.