• Title/Summary/Keyword: IEC Standards

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A Study on the Analysis of Transient Overvoltages and Harmonics due to Utility STATCON Switching (전력회사의 스타콘 투입시 과도 전압 상승과 고조파 분석에 관한 연구)

  • 김경철;서범관;송영주;이일무
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.17 no.5
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    • pp.51-59
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    • 2003
  • The utility and many customers employ capacitor banks(STATCON so called at the utility) to help control the power factor(customers) or voltage(the utility) by supplying reactive power to inductive loads. This paper presents analysis of transient overvoltages and harmonics due to utility STATCON switching. One simple and inexpensive means of limiting the voltage magnification transient and reducing harmonics is to switch the capacitor banks on a few minutes after the STATCON has been switched. Simulation results used the EDSA software package show the effects of decreased the transient voltage and harmonic reduction at the customer. And also harmonic limits based on the well-known international harmonic standards IEEE 519 and IEC 1000 are evaluated for the customer.

Application and Design of Metrics for Software Process Measurement (소프트웨어 프로세스 측정을 위한 척도 설계 및 활용)

  • Hwang Sun-Myung;Yeom Hee-Gyun
    • The KIPS Transactions:PartD
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    • v.12D no.7 s.103
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    • pp.937-946
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    • 2005
  • In the current marketplace, there are maturity models, standards, methodologies and guidelines that can help an organization improve the way it does business. All SPI models including ISO/IEC I5504 and CMMI provide the capability level of software process. However, most available improvement models focus on a specific goals and Practices of the processes So my assessors need an objective process measure how to estimate achievement of goals and practices. We proposed quantitative process capability metric (PCM) which can determine the degree of capability And the effective measuring approach help SPI assessor as well as organization unit.

A Quality Model of National R&D Projects based on ISO/IEC Standards (ISO/IEC 국제표준에 기반한 국가연구개발사업 품질측정모델에 관한 연구)

  • Song, Byeong-Sun;Lee, Jae-Sung;Rhew, Sung-Yul;Lee, Nam-Yong
    • Journal of Information Technology Services
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    • v.7 no.3
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    • pp.31-45
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    • 2008
  • The number of national research and development(R&D) projects have been continually increased, and it is necessary that the efficiency of investment of R&D projects have been improved during the last two decades. also the government has improved national R&D process and supporting tools for the projects. However, it is not enough to develop a quality model to evaluate the projects systematically. Therefore, a quality model for national R&D projects need to be revised. The quality model for the projects should be based on the global standard(ISO/IEC 9126). In this paper, the authors proposed a quality model for national R&D projects and took a case study for verification of the quality model. The quality model is defined in terms of functionality, reliability, usability, efficiency, portability and maintainability. Also, the authors suggest metrics for measuring the quality of products or services. finally, The productivity and quality of national R&D projects will be improved by the quality model.

Time-varying Harmonics Measurement and Evaluation of the High Speed Electric Train Loads (시간에 따라 변하는 고속철 부하의 고조파 측정 및 평가)

  • Jin, Seong-Eun;Kim, Kyung-Chul;Lee, Joo-Hong;Jeon, Young-Soo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.20 no.7
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    • pp.29-37
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    • 2006
  • High speed electric trains have nonlinear loads including converters and inverters for the control synchronous motors. Harmonics produced by these devices are large, but also have noticeable time varying characteristics. Since the large loads are supplied from the power system grid, it must be recognized that not only will the system of utility be impacted, but neighboring customer system could be impacted as well. In this paper time-varying harmonics for high speed electric train loads are measured and evaluated by international harmonic standards IEEE Std. 519 and IEC 61000-3-6 using a cumulative probablistic approach.

An Assessment of Electric Shock Hazard by Safety Criteria Using Graphical Method (그래프법을 이용한 안전기준에 의한 감전위험성 평가)

  • 김두현;강동규
    • Journal of the Korean Society of Safety
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    • v.16 no.3
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    • pp.53-60
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    • 2001
  • This paper presents a graphical method for hazard assessment of electric shock by safety criteria. For the human body to be safety actual body current should not exceed safety criteria, i.e. allowable body current. The assessment method presented in this paper is based m the safety criteria of the IEEE Standard 80 as well as the IEC 479-1. The hazard can be assessed in terms of alterable touch voltages instead of alterable body current. Thus, the hazard assessment of given electric shock condition is referred to a procedure by which the actual touch voltages are compared with the allowable (safe) touch voltages. Since the IEC 479-1 safety criteria are nonlinear, the graphical method is presented for the hazard assessment. Body current and body voltage are calculated with the allowable touch voltage. A comparison of the safety criteria of two widely accepted standards, i.e. the IEEE Std 80 End the IEC 479-1 is proposed. Also Thevenin equivalent resistance is obtained from electric shock model expressed by two-port earth-grid-foot system. On the basis of calculated results, the allowable touch voltage, the body current and the body voltage we can conduct the hazard or safety assessment and estimate the severity of electric shock.

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The Development of Gateway System for Power Automation based on TETRA (TETRA 기반 전력자동화 게이트웨이 시스템 개발)

  • Song, Byung-Kwen;Kim, Geon-Ung
    • Journal of IKEEE
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    • v.14 no.2
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    • pp.41-50
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    • 2010
  • TETRA is the standard of Digital Trunked Radio System suggested by the ETSI(European Telecommunications Standards Institut ). It is adopted as Electric Power IT Wireless Backbone Network in Korea. Police station and Fire Station are using TETRA network. Currently, Power Automation Protocols are DNP3.0 in Distribution Automation System, DLMS in Auto Metering Infrastructure, IEC61850 in Substation Automation. These protocols are transmissions using CDMA or WCDMA modem. If Power Automation protocol uses TETRA networks, it can be interoperable with the systems in police or fire stations. And it has outstanding ability to handle problems in a disaster situation. So, This paper propose a gateway system of Power Automation which can transmit the power automation protocol using TETRA.

RMT: A Novel Algorithm for Reducing Multicast Traffic in HSR Protocol Networks

  • Nsaif, Saad Allawi;Rhee, Jong Myung
    • Journal of Communications and Networks
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    • v.18 no.1
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    • pp.123-131
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    • 2016
  • The high-availability seamless redundancy (HSR) protocol is one of the most important redundancy IEC standards that has garnered a great deal of attention because it offers a redundancy with zero recovery time, which is a feature that is required by most of the modern substation, smart grid, and industrial field applications. However, the HSR protocol consumes a lot of network bandwidth compared to the Ethernet standard. This is due to the duplication process for every sent frame in the HSR networks. In this paper, a novel algorithm known as the reducing multicast traffic (RMT) is presented to reduce the unnecessary redundant multicast traffic in HSR networks by limiting the spreading of the multicast traffic to only the rings that have members associated with that traffic instead of spreading the traffic into all the network parts, as occurs in the standard HSR protocol. The mathematical and the simulation analyses show that the RMT algorithm offers a traffic reduction percentage with a range of about 60-87% compared to the standard HSR protocol. Consequently, the RMT algorithm will increase the network performance by freeing more bandwidth so as to reduce HSR network congestion and also to minimize any intervention from the network administrator that would be required when using traditional traffic filtering techniques.

A Study on the Series Resonant Filler Application and Evaluation for Personal Computer Loads (컴퓨터부하의 직렬 동조필터 적용 및 평가에 관한 연구)

  • 김경철;강윤모;이일무;송영주
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.17 no.3
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    • pp.40-48
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    • 2003
  • Computer loads can be found in all of modem society. The switching mode power supplies used in personal computers are major sources of harmonic currents. Harmonic currents can cause lots of harmonic problems such as voltage waveform distortion, excessive neutral currents, errors in measurements, and disruption in computer performance. The purpose of this paper is to give an equivalent circuit modeling methodology for the harmonic currents generated by single-phase personal computer loads and to evaluate a commercially available series resonant filter for the harmonic currents compensation based on the IEEE 519-1992 and IEC1000-3-2 standards for limiting harmonic distortion.

RFID Standardization Trends and Mobile RFID Services (RFID 표준화 동향)

  • Lee, Jun-Seob;Kim, Hyoung-Jun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.1
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    • pp.754-756
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    • 2005
  • RFID(Radio Frequency Identification) is used to describe a system that transmits the identity of an object or person wirelessly using radio waves. RFID is recognized as a key technology of USN(Ubiquitous Sensor Network). ISO/IEC JTC1 and EPCglobal are developing RFID related standards for global supply chain management. RFID is an important solution not only for the supply chain management, but also for USN and future services. Recently, mobile RFID which provide various services using RFID reader in mobile phone, is being standardized in Korea. In this paper, we analyze trends of RFID standardization activities in ISO/IEC JTC1 and EPCglobal and mobile RFID, and propose an convergence scenario of IPv6 and RFID.

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Life Cycle Cost Analysis of Main Conversion System in 8200 Series Electric Locomotive (8200호대 전기기관차 주변환장치 LCC 분석)

  • Kim, Wan-il;Lee, Kye-Seung;Choi, Jong-Rok;Kim, Jae-Moon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.12
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    • pp.1830-1835
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    • 2017
  • 8200 Series Electric Locomotives are mostly imported from overseas due to aging and uncertainty of source technology, and it's the maintenance cost is increasing. We are analyzed life cycle costs based on international standards such as IEC 60300-3-3 and IEC62278. The main conversion system of the 8200 series electric locomotive is closely related to vehicle operation and is one of the subsystems requiring frequent maintenance. In this paper, the life cycle cost of the main conversion unit in 8200 series electric locomotive is analyzed based on the maintenance manual. As a result of analysis, maintenance cost of GTO module and control device is relatively high, and it is confirmed that the cost increases according to the useful life.