• 한국철도학회논문집
• /
• 제7권4호
• /
• pp.356-359
• /
• 2004

In this paper, as the first step to assess and enhance the reliability of Korea High Speed Train, auxiliary power system is selected and reliability analysis is carried out. The auxiliary power system is classified into subsystems and functional analysis is conducted. Reliability block diagrams are drawn and reliability parametric analysis is performed. Analysis results show that the reliability of auxiliary power system depends on critical items. To grow the system reliability, activities should be concentrated on improvement of critical items.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2005년도 추계학술대회 논문집
• /
• pp.682-687
• /
• 2005

High quality power supplying of power distribution system in electric railway system is the important function. Power feeding system is complicated witch is compose with distribution line, circuit break, protection facilities and so on. Among this components, role of substation is most important for elevation of reliability in electric power system. Therefore, the enhanced reliability considering the preventive inspection, repair work, replacement is necessary. In this study, a proposed the enhanced reliability method through a calculation of fault probability in power feeding system.

• 산업기술연구
• /
• 제26권B호
• /
• pp.135-144
• /
• 2006

The significance of hydro-power plant is increasing in its public roles such as flood control and water supply as well as electric power production. Even if high level of reliability in facility operation is required, no specific reliability research has been made. This specifically stems from the lack of technology and research investments. The eventual goal of this study is to secure a methodology for reliability analysis of hydro-power plant so that an appropriate decision for operation and investment can be made. Specific effort was put to develop a reliability model for water supply system within hydro-power plant. For this study, we briefly examined the overview of the hydro-power plant including the electric power generation facility system. We then discussed the facility reliability analysis methodology for hydro-power plant. Based on rigorous examination of the water supply system and components roles, we drew major failure modes for each component and examined their effects.

• 전기학회논문지
• /
• 제64권11호
• /
• pp.1535-1542
• /
• 2015

An increasing number of electric vehicles (EVs) in power system affects its reliability in various aspects. Especially under high EV penetration level, new generating units are required to satisfy system's adequacy criterion. Wind power generation is expected to take the major portion of the new units due to environmental and economic issues. In this paper, the system reliability is analyzed using Loss of Load Expectation (LOLE) and Expected Energy Not Served (EENS) under each and both cases of increasing wind power generation and EVs. A probabilistic multi-state modeling method of wind turbine generator under various power output for adequate reliability evaluation is presented as well. EVs are modeled as loads under charging algorithm with Time-Of-Use (TOU) rates in order to incorporate EVs into hour-to-hour yearly load curve. With the expected load curve, the impact of EVs on the system adequacy is analyzed. Simulations show the reliability evaluation of increasing wind power capacity and number of EVs. With this method, system operator becomes capable of measuring appropriate wind power capacity to meet system reliability standard.

• 시스템엔지니어링학술지
• /
• 제14권2호
• /
• pp.49-57
• /
• 2018

The main objective of this paper is come up with methodology approach for FPGA-based system in verification and validation lifecycle regarding software reliability using system engineering approach. The steps of both reverse engineering and re-engineering are carried out to implement an FPGA-based of safety critical system in Nuclear Power Plant. The reverse engineering methodology is applied to elicit the requirements of the system as well as gain understanding of the current life cycle and V&V activities of FPGA based-system. The re-engineering method is carried out to get a new methodology approach of software reliability, particularly Software Reliability Growth Model. For measure the software reliability of a given FPGA-based system, the following steps are executed as; requirements definition and measurement, evaluation of candidate reliability model, and the validation of the selected system. As conclusion, a new methodology approach for software reliability measurement using software reliability growth model is developed.

• 전기학회논문지
• /
• 제60권7호
• /
• pp.1305-1313
• /
• 2011

Web based online real-time reliability integrated information system is asked rapidly for more efficiency and demand response in recent. As the utilization of renewable resources has been receiving considerable attention in recent years, the information system requirement is increased. Specially, the reliability information system is more important for implementing the smart grid. This paper describes architecture of the WORRIS(Web based Online Real-time Reliability Integrated Information System) Version 7.0 system that simulates the reliability indices in composite power system considering wind turbine generators(WTG) developed successfully in this paper. And we had simulated the case study using Jeju island power system data.

• Journal of Electrical Engineering and Technology
• /
• 제8권4호
• /
• pp.704-711
• /
• 2013

Data center is an information hub and resource for information-centric society. Since data center houses hundreds to ten thousands servers, networking and communication equipment, and supporting systems energy saving is one of the hottest issues for green data center. Among several solutions for green data center this paper introduces higher voltage direct current (DC) power feeding system. Contrary to legacy alternating current (AC) power feeding system equipped with Uninterruptible Power Supply (UPS), higher voltage DC power feeding system is reported to be a more energy efficient and reliable solution for green data center thanks to less AC/DC and DC/AC conversions. Main focus of this paper is on reliability issue for reliable and continuous operation of higher voltage DC power feeding system. We present different types of configuration of the power feeding systems according to the level of reliability. We analyze the reliability of the power feeding systems based on M/M/1/N+1/N+1 queueing model. Operation of the power feeding system in case of failure is also presented.

• 조명전기설비학회논문지
• /
• 제29권1호
• /
• pp.86-93
• /
• 2015

Globally, wind power development is experiencing dramatic growth and wind power penetration levels are increasing. Wind generation is highly variable in time and space and it doesn't guarantee the system reliability and secure system operation. As wind power capacity becomes a significant portion of total generation capacity, the reliability assessment for wind power are therefore needed. At present, this operational reliability assessment is focusing on a generation adequacy perspective and does not consider transmission reliability issues. In this paper, we propose the critical transmission operating constraint prediction(CTOCP) system with high wind power penetration to enhance transmission reliability.

• KIEE International Transactions on Power Engineering
• /
• 제4A권2호
• /
• pp.84-90
• /
• 2004

This paper presents a new method for choosing the best line for transmission system expansion planning considering the highest reliability level of the transmission system. Conventional methodologies for transmission system expansion planning have been mainly focused on economics, which is the minimization of construction costs. However, quantitative evaluation of transmission system reliability is important because successful operation and planning of an electric power system under the deregulated electricity market depends on transmission system reliability management. Therefore, it is expected that the development of methodology for choosing the best lines considering the highest transmission system reliability level while taking into account uncertainties of transmission system equipment is useful for the future. The characteristics and effectiveness of the proposed methodology are illustrated by the case study using a MRBTS.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
• /
• pp.48-50
• /
• 2005

New environment change of electric power system focused in consumer's energy supply and demand. But electric power reliability preservation and reliability improvement countermeasure also need for long-term. It is need that change equipments that is composing electric power system in well-timed time and by maintaining, prevent breakdown beforehand and prevent consumer's power interruption by equipment fail. However, as only quantitative estimation is available by reliability estimation method that is presented in existing, it is no to use in dictionary fault prevention. Therefore, applied optimum reliability preservation through existent equipment fault data analysis of electric power system in equipment replace side, and this when maintain equipment replace of electric power system for reliability preservation using responsiveness analysis to base ordering evaluate. In existing about main equipment plain that this paper is power system the valued failure rate use this by score and precedence of electric power system equipment for replace of system considered expense.