• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.9
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• pp.1663-1667
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• 2011

Voltage variation caused by large loads such as arc furnace and large motors, which use the large and instantaneous currents, can cause the voltage flicker. The flicker irritates the human's eyes and also has an adverse effect on protection device, rotating machine and electronic device etc, therefore the flicker needs to be managed effectively. Recently, the Korea power quality standard has been established on the IEC standards. This paper presents the flicker management standard for distribution power system and suggests the flicker transfer coefficients for Korea power system based on the IEC 61000-3-7.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.62 no.3
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• pp.151-158
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• 2013

Large generator of power plant is very important. In order to protect large generator from faults, digital protective relay or IED is required. However, all protective relays for generators of the domestic power plant are operated by foreign products. And now, for technological independence from foreign and improvement of import substitution effect, IEDs using domestic technology are being developed. To evaluate performance of developing next-generation power devices, the study of the dynamic characteristics of the power plant, generator system modeling, fault simulation and analysis, should be considered. Specially, To obtain IEEE Standards COMTRADE format for relay operation test, generator system modeling and fault simulation using PSCAD/EMTDC tools must be preceded. Until now, a complete modeling of generator internal windings and fault simulation techniques dose not exist. In this paper, for evaluation performance of relay elements of developing IED, the generator system modeling and various faults simulation using PSCAD/EMTDC tools were performed. And then, the various transient phenomena through obtained relaying signal of developed modeling were analyzed.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.12 no.1
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• pp.56-61
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• 2016

After Japanese Fukushima nuclear power plant accident caused by the beyond design basis earthquake and tsunami, it has turned to be a major challenge for nuclear safety. IAEA, US NRC and EU have provided new safety design standards for beyond design basis event, Domestic regulatory bodies have also enacted guidances for licensees and applicants on additional methods related to beyond design basis events. This paper describes several evaluation methods for applying to nuclear power plants piping for beyond design basis earthquake. As a results, energy method based on the absorbed energy on nuclear power plant, deterministic method following design code and theory, experience method considering past earthquake data and information and probabilistic methods similar to probabilistic risk assessment were reviewed.

• International Journal of Control, Automation, and Systems
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• v.3 no.spc2
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• pp.363-375
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• 2005

The paper describes some of the challenges that face the control of nonlinear interconnected power systems. The challenges include the selection of appropriate control and information structures that could range from a completely decentralized to a fully centralized structure. Once a structure is proven to be feasible, the effectiveness of control signals needs to be assessed. Analytical tools are derived for this purpose in the first part of the paper, and they are illustrated with a case study that involves the design of a damping decentralized controller using a Thyristor Controlled Series Compensation device. The second part of the paper deals with the load following and tracking problem through automatic generation control for a system that has been re-structured or deregulated. This problem can be solved using a completely decentralized scheme. It is solved here using fuzzy rules and with an emphasis on compliance with NERC's standards and reduction of wear and tear of the equipment. It is illustrated with a test system that has three interconnected control areas. Finally, comments on the economics of control and the author's vision are presented.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.184-185
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• 2014

International construction contracts to Korean construction companies have been dramatically increased over the 48 years (Contract received worth 65.2 billion dollars in 2013). Especially, the plant construction sector has achieved about 61% among the 65.2 billion dollars. Under this trend, in order to ensure plant construction's competitiveness, 'standard classification' is an important area for systematic management. However, these standards in the plant construction are not widely utilized yet, in comparison with civil and building sectors. Therefore, in this research, a higher level of standard classifications is proposed for various types of power plants from a PMO's (Project Management Office) perspective. This study also provides a comparative analysis outlining different features and common components based on various types of power plants.

• Journal of Power Electronics
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• v.12 no.2
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• pp.268-275
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• 2012

Based on the standards that limit the harmonic pollution of electronic systems, the use of PFC converters is mandatory. In this paper, a new resonant bridgeless PFC converter is introduced. By eliminating the input bridge diodes, the efficiency is improved. Moreover, soft switching conditions for all of the semiconductor elements are achieved without adding any extra switches. As a result, high efficiency is attained. The proposed converter is analyzed and the theoretical and simulation results of the proposed converter are presented. In order to verify the validity of the analysis, a 40 w prototype converter is implemented and experimental results are presented. The experimental results show that high efficiency is attained while achieving a high power factor.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.1
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• pp.136-145
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• 1997

To analyzed ride quality and to predict durability in vehicle dynamics, it is essential to describe a road surface profile precisely. This paper presents a technique to generate road surface profiles in a spatial domain by using a power spectral density function. A single track power spectral density function is proposed to describe a road surface profile, which is also applicable for multi-track vehicle response analysis, The derived road surfaces are compared to ISO(International Organization for Standardization) standards and classifications, proposed by the MIRA(Motor Industry Research Association). The methodology in this paper is also proposed to generate road roughness description with a limited external data. A small amount of external curve data is combined with an internal PSD function to generate road surface roughness in a spatial domain.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1131-1136
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• 2008

The single-phase PWM converter employing power semiconductors is currently applied to the power unit of high-speed rail vehicle and increasingly used as the front-end converter with properties of near unity power factor. Power factor and harmonics are increasingly important needs for drive system of high-speed rail vehicle. The proposed approach has many advantages which include fewer semiconductor components, simplified control, high performance features and satisfies IEC 555 harmonic current standards. Simulation results show that the dc-link voltage control obey the reference value during constant load and input current is near sinusoidal.

• Journal of Auto-vehicle Safety Association
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• v.8 no.3
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• pp.22-27
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• 2016

As a preliminary research to provide amendment for the engine performance test regulation of two-wheeled vehicles, the engine performance data are investigated in terms of maximum torque, rated power, and engine speed of motorcycles on sales in Korean market. Based on the engine performance database officially published to consumers, some forecasted problems are discussed when the maximum torque and the rated power are measured under the present test standards. EU and Korea regulations on engine performance test are carefully compared in terms of the accuracy of measurement devices, test procedures including data acquisition method, and allowable range of rated power measurement. Complementary items are discussed to eliminate ambiguities in the present regulation and to construct rational regulation system.

• Proceedings of the KIPE Conference
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• 2013.07a
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• pp.481-482
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• 2013

This paper presents the method to determine the battery capacity for controlling the wind power with BESS for stabilizing the output of HanGeong wind farm in accordance with grid codes for distributed generators in Jeju Island. To find appropriate capacity of BESS, three kinds of simulations are carried out : There are focused on smoothing control, the frequency fluctuation and the renewable energy resources standards, respectively. As the simulation result, maximum C-rates of BESS for the wind farm are calculated as 2C, 5C and 2C that are for each method and battery capacities have 25%, 20% and 10% of total capacity of HanGeong wind farm. Finally, simulations for this paper are carried out by using PSCAD/EMTDC.