• Title/Summary/Keyword: power systems

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Dynamic Analysis of Doubly-Fed Induction Generators for Wind Power Applications (이중여자 권선형 유도 발전기에 의한 풍력발전시스템의 동특성 해석)

  • Jang, Seok-Myeong;Choi, Jang-Young;Cho, Han-Wook;Park, Ji-Hoon;Yoon, Ki-Kab
    • Proceedings of the KIEE Conference
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    • 2006.07b
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    • pp.1183-1184
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    • 2006
  • Using the MATLAB/SIMULINK, this paper presents dynamic simulation model for 6MW wind power generation systems with the DFIG considering distribution systems and performs the dynamic analysis of wind power systems

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A Synchronous-Reference-Frame-Based Control of Single-Phase UPQC for Improving Power Quality of AC Electrified Railway Systems (전기철도 급전시스템의 전기품질 향상을 위한 동기좌표계를 이용한 단상 UPQC의 제어)

  • Park, Han-Eol;Song, Joong-Ho
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.1951-1958
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    • 2009
  • This paper presents a synchronous-rotating-frame-based control of single-phase UPQC(Unified Power Quality Conditioner) to improve power quality in ac electrified railway systems. The simulation results show that the UPQC can compensate the harmonic supply voltages, the harmonic load currents, and the reactive power in electrified railway systems. Validity of the proposed UPQC control method based on the synchronous rotating frame is illustrated through the simulation results.

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Optical Sensor Technology for Supervisory and Control of Electric Power System (전력 시스템 감시 제어용 광센서 기술)

  • Kim, Young-Soo
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.2189-2191
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    • 2000
  • Electric power systems are becoming advanced by using new technology year by year However, in electric power system environments. electromagnetic interference occurs in measurement, supervisory and control systems, especially in sensors. Optical sensor technologies are useful for solving the problem, since they are not affected by electromagnetic interference because they are composed of insulting materials. In this paper, some applications of optical sensor technology to electric power systems are introduced.

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Field Test on IEC60364-4-44 for the Application in Korean distribution system (IEC60364-4-44의 국내 배전계통 적용을 위한 실증시험)

  • Nam, Kee-Young;Choi, Sang-Bong;Jeong, Seong-Whan;Lee, Jae-Duck;Ryoo, Hee-Suk;Kim, Dae-Kyeong
    • Proceedings of the KIEE Conference
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    • 2006.07a
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    • pp.486-487
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    • 2006
  • The authors have studied on the application of IEC 60364-4-44 to Korean electrical installations of buildings from 2004 sponsored by Korean ministry of commerce, industry and energy and the test field is established in K.E.R.I. (Korea Electrotechnology Research Institute). This paper presents the summary results of establishment of test field and analysis for the application of IEC 60364 in Korea. IEC 60364-4-44 provides rules for the protection against the effects of conducted and radiated disturbances on electrical installations. Especially this standard deals with the protection of low voltage facility against the ground fault in the high voltage side of power distribution system. Many countries define the regulations on the use and production of electrical facilities based on their own power system and technical references which are considered to be suitable for them. The background of circuit of IEC 60364-4-44 is based on the ungrounded system as most of European countries. However, since Korean electric power distribution system is based on multi-grounding system different from European system, it is necessary to evaluate or prove the effect of the IEC 60364-4-44 for introducing and applying it to the domestic grounding system as a Korean standard. This paper presents the establishment of test field to get background data to introduce the IEC 60364-4-44 and to evaluate the standard is applicable to domestic rule for the protection against ground fault through the related test

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Integrated Operation of Power Conversion Module for DC Distribution System (직류 배전 시스템을 위한 전력 변환 모듈의 통합 운전)

  • Lee, Hee-Jun;Shin, Soo-Choel;Hong, Suk-Jin;Won, Chung-Yuen
    • The Transactions of the Korean Institute of Power Electronics
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    • v.19 no.3
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    • pp.240-248
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    • 2014
  • It is DC power that Output of renewable energy being recently developed and researched. Also, demand of DC power will expect to proliferate due to increase of digital load. Thus, DC distribution system providing high quality of power and reliability has emerged as a new distribution system. If the conventional distribution systems are substituted by proposed DC distribution system, the output of renewable energy can be connected with distribution systems under minimum power conversion. Therefore, in the event of connection with DC load, it can construct an efficient distribution system. In this paper, the integrated parallel operation of power conversion module for DC distribution system is proposed. Also, this paper proposed modularization of power conversion devices for DC distribution system and power control for parallel operation of large capacity system. DC distribution system consists of three power conversion modules such as AC/DC power conversion module 2 set, ESS module 1 set. DC distribution system controls suitable operation depending on the status of the DC power distribution system and load. Integrated operation of these systems is verified by simulation and experiment results.

A Novel Anti-Islanding Method for Utility Interconnection of Distributed Power Generation Systems

  • In-Ho
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • v.4B no.4
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    • pp.217-224
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    • 2004
  • A novel anti-islanding method for the distributed power generation system (DPGS) is proposed in this paper. Three different islanding scenarios are explored and presented based on the analysis of real and reactive power mismatch. It is shown via investigation that islanding voltage is a function of real power alone, where its frequency is a function of both real and reactive power. Following this analysis, a robust anti-islanding algorithm is developed. The proposed algorithm continuously perturbs ($\pm$5%) the reactive power supplied by the DPGS while simultaneously monitoring the utility voltage and frequency. In the event of islanding, a measurable frequency deviation takes place, upon which the real power of the DPGS is further reduced to 80%. A drop in voltage positively confirms islanding and the DPGS is then safely disconnected. This method of control is shown to be robust: it is able to detect islanding under resonant loads and is also fast acting (operable in one cycle). Possible islanding conditions are simulated and verified through analysis. Experimental results on a 0.5kW fuel cell system connected to a utility grid are discussed.

The Survey for Communication Protocols adopted by Automation Systems (전력자동화 통신프로토콜 표준화 동향)

  • Kim, Myong-Soo;Kim, Su-Bae;Lim, Yong-Hun;Hyun, Duck-Hwa;Kim, Chung-Hwan
    • Proceedings of the KIEE Conference
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    • 2004.07d
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    • pp.2414-2416
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    • 2004
  • Power Companies worldwide are undergoing tremendous change in the Automation issues. It becomes a worldwide trend that the power utilities focus their attention to the automation of their power plants and substation systems, employing recent advanced communication protocols. In this paper, we discuss the standard communication protocols which can be applied in the automation systems to help utilities reduce their operation and maintenance costs while at the same time meeting new requirements for communications to RTUs and intelligent electronic devices(IEDs). Especially, we introduce EC 61850 protocol which is developing for international standard by IEC.

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Transmit Antenna Selection for Quadrature Spatial Modulation Systems with Power Allocation

  • Kim, Sangchoon
    • International journal of advanced smart convergence
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    • v.9 no.1
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    • pp.98-108
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    • 2020
  • We consider transmit antenna selection combined with power allocation for quadrature spatial modulation (QSM) systems to improve the error rate performance. The Euclidean distance-based joint optimization criterion is presented for transmit antenna selection and power allocation in QSM. It requires an exhaustive search and thus high computational complexity. Thus its reduced-complexity algorithm is proposed with a strategy of decoupling, which is employed to successively find transmit antennas and power allocation factors. First, transmit antennas are selected without considering power allocation. After selecting transmit antennas, power allocation factors are determined. Simulation results demonstrate considerable performance gains with lower complexity for transmit antenna selected QSM systems with power allocation, which can be achieved with limited rate feedback.