• Title/Summary/Keyword: The amplification of harmonic current

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Gold-sapphire Plasmonic Nanostructures for Coherent Extreme-ultraviolet Pulse Generation

  • Han, Seunghwoi
    • Current Optics and Photonics
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    • v.6 no.6
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    • pp.576-582
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    • 2022
  • Plasmonic high-order harmonic generation (HHG) is used in nanoscale optical applications because it can help in realizing a compact coherent ultrashort pulse generator on the nanoscale, using plasmonic field enhancement. The plasmonic amplification of nanostructures induces nonlinear optical phenomena such as second-order harmonic generation, third-order harmonic generation, frequency mixing, and HHG. This amplification also causes damage to the structure itself. In this study, the plasmonic amplification according to the design of a metal-coated sapphire conical structure is theoretically calculated, and we analyze the effects of this optical amplification on HHG and damage to the sample.

Harmonic Analysis Model based on PSCAD/EMTDC

  • Lee, Han-Min;Lee, Chang-Mu;Jang, Gil-Soo;Kwon, Sae-Hyuk
    • KIEE International Transactions on Power Engineering
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    • v.4A no.3
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    • pp.115-121
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    • 2004
  • This paper presents the model for an AC electric railway system using the PSCAD/EMTDC program. It is composed of a scott-transformer, an auto-transformer, catenary and electric trains, etc. After obtaining the models of the fundamental elements describing the AC electric railway system and its behavior, we have analyzed and tested an actual AC electric railway system focused on the amplification of harmonic current to verify the proposed model. The simulation results from the proposed approach and the measurement data from the test are described.

A study on Harmonic Analysis of Electric Railway System Using EMTOG (EMTDC를 이용한 전기철도 급전계통의 고조파 해석에 관한 연구)

  • Lee, H.M.;Han, M.S.;Oh, K.H.;Lee, C.M.;Park, H.J.
    • Proceedings of the KIEE Conference
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    • 2003.07b
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    • pp.1276-1278
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    • 2003
  • The magnified current harmonics usually brings about various problems. That is, the current harmonics makes interference in the adjacent lines of communications and the railway signalling system. Furthermore, in case it flows on the side of power system, not only overheating and vibration at the power capacitors but also wrong operation at the protective devices can occur. Therefore, the exact assessment of the harmonic current flow must be undertaken at design and planning stage for the electric traction systems. From these point of view, this study presents the harmonic analysis and the modelling of traction power feeding system focused on the amplification of harmonic current.

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Analysis of the amplification of Harmonic Current Using EMTDC in Kyongbu High-Speed Railway (EMTDC를 이용한 경부고속철도 고조파 전류 확대율 해석)

  • Lee H.M;Lee C.M
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.1379-1381
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    • 2004
  • This paper presents the AC electric railway system modeling using PSCAD/EMTDC program. This system model is composed of the scott-transformer the auto-transformer. the running rails. the protection wires, the feeders. the catenary and contact wires, etc. After obtaining the models of the fundamental elements describing the AC electric railway system and its behavior, we have analyzed and tested real traction power feeding system focused on the amplification of harmonic current to verify the proposed model. The simulation results from the proposed approach and the measurement data from the test are described in the paper.

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A Reduced Equivalent Line Constant of the Catenary System (전차선로 시스템의 축약 등가 선로정수에 관한 연구)

  • 이한민;오광해;이장무;박현준;장길수;권세혁
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.53 no.8
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    • pp.421-431
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    • 2004
  • Line constants are composed by impedances and susceptances. A paper which was published estimated only impedances of line constants. Therefore, this paper estimates susceptances as well as impedances of equivalent five-conductors model using the reduced equivalent method. In order to verify estimated line constants, we measured line constants of real railway system. And we compared calculated results with measured data on 60Hz∼3000Hz. For the other verification, the calculation results from the proposed model and the measurement data from the test are compared focused on the amplification of harmonic current in the paper.

Harmonic Analysis for Traction Power Supply System with Common Grounding (공동접지방식 급전시스템의 고조파 해석)

  • 오광해;이한민;장동욱;김주락
    • Proceedings of the KSR Conference
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    • 2000.11a
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    • pp.688-695
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    • 2000
  • This study presents an approach to model and to analyse traction power feeding system focused on the amplification of harmonic current. Through the research we can conclude the following: - The resonance frequency is not depend on the location of vehicle. The magnification of harmonic is, however, a function of the position of a train. - The resonance frequency is lower as catenary length is longer.

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8-Port Network Model for Harmonic Analysis on the Test Track in Seoul-Pusan High-Speed Railway (경부고속철도 시험선로의 고조파 해석을 위한 10단자 회로망 모델)

  • Oh, Kwang-Hae;Lee, Han-Min;Chang, Sang-Hoon
    • Proceedings of the KIEE Conference
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    • 2001.04a
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    • pp.429-432
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    • 2001
  • This study presents an approach to model and to analyse traction power feeding system focused on the amplification of harmonic current. Through the research, 8-port network model which can be effectively applied to harmonic analysis is derived.

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8-Port Network Model for Harmonic Analysis on the Test Track in Seoul-Pusan High-Speed Railway (경부고속전철 시험선로의 고조파 해석을 위한 10단자 회로망 모델)

  • O, Gwang-Hae;Lee, Han-Min;Chang, Sang-Hun;Kim, Jeong-Hun
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.51 no.3
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    • pp.99-106
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    • 2002
  • This study presents an approach to model the Electric Railway System with the common grounding based on the 8-port network model and to analyse traction power feeding system focused on the amplification of harmonic current. The entire system can be easily modeled by the combination of 8-port representation of each component in parallel and/or series. Through the research, 8-port network model which can be effectively applied to harmonic analysis is derived.

Amplification of Current Harmonics Due to Self-Excitation Capacitors for Wind Induction Generators (자여자 풍력 유도발전기의 캐패시터에 따른 고조파 전류의 증폭)

  • Oh, Yong;Choi, Yong-Sung;Hwang, Jong-Sun;Lee, Kyung-Sup
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.57 no.2
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    • pp.192-197
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    • 2008
  • The value of this paper is to use reduced size apparatuses to perform field measurement in order to identify and validate that the harmonic-current effects are due to the presence of self-excitation capacitance connected at stator's terminals of the studied SEIG. This paper has presented the measured electrical quantities of a three-phase $\Delta$-connected wind induction generator (WIG) under sudden connection and disconnection of resistive loads. An intelligent power-system recorder/monitor has been employed to measure three-phase voltages and currents of the studied system at the terminals of the studied WIG and the load. The measured electrical quantities have been analyzed. Total harmonic distortion (THD) of current using cumulative probability density function has been employed to determine the penetration of harmonic distortion at load side. The results show that the harmonic currents generated by the studied WIG can be severely amplified by the connected self-excited capacitance at the stator's terminals.

A Study on the Propagation of Harmonic Current in the Traction Power Supply System (철도 전력공급시스템에서의 고조파전류 확대현상에 관한 연구)

  • Oh, K.H.;Chang, S.H.;Han, M.S.;Lee, C.M.;Shin, H.S.
    • Proceedings of the KIEE Conference
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    • 1998.07c
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    • pp.908-910
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    • 1998
  • Modern AC electric car has PWM(Pulse Width Modulation) -controlled converters, which give rise to higher harmonics. The current harmonics injected from AC electric car is propagated through power feeding circuit. As the feeding circuit is a distributed constant circuit composed of RLC, the capacitance of the feeding circuit and the inductance on the side of power system cause a parallel resonance and a magnification of current harmonics at a specific frequency. The magnified current harmonics usually brings about various problems. That is, the current harmonics makes interference in the adjacent lines of communications and the railway signalling system. Furthermore, in case it flows on the side of power system, not only overheating and vibration at the power capacitors but also wrong operation at the protective devices can occur. Therefore, the exact assessment of the harmonic current flow must be undertaken at design and planning stage for the electric traction systems. From these point of view, this study presents an approach to model and to analyse traction power feeding system focused on the amplification of harmonic current. The proposed algorithm is applied to a standard AT(Auto-transformer)-fed test system in which electric car with PWM-controlled converters is running.

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