• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.6
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• pp.296-301
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• 2002

Modern power systems are very complex and to model them completely is impractical for electromagnetic transient studies. Therefore areas outside the immediate area of interest must be represented by some form of Frequency Dependent Network Equivalent (FDNE). In this paper a method for developing Frequency Dependent AC system Equivalent (FDACSE) using Z-domain rational Function Fitting is presented and demonstrated. The FDACSE is generated by Linearized Least Squares Fitting(LSF) of the frequency response of a Z-domain formulation. This 1 & 2 port FDACSE have been applied to the New Zealand South Island AC power system. The electromagnetic transient package PSCAD/EMTDC is used to assess the transient response of the 1 & 2 port FDACSE developed under different condition (linear load, fault and nonlinear loading). The study results have indicated the robustness and accuracy of 1 & 2 port FDACSE for electromagnetic transient studies.

• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.867-870
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• 1997

This paper presents application of battery energy storage system(BESS) for interconnection with power distribution system. We configured interconnection model using PSCAD/EMTDC program. The simulation for voltage regulation on BESS interconnection with power distribution analyzes transient voltage variation, steady state voltage variation, and voltage of reverse power flow at interconnected feeder and nearby feeder.

• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.298-300
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• 2008

고립된 소규모 전력시스템에 소형 풍력발전기를 계통연계 운전할 때 나타날 수 있는 전압변동을 예측하기 위한 방법에 관해 연구하였다. 이를 위하여 고립된 계통에 연결된 기존발전소 및 부하, 변압기, 풍력발전기의 간략화된 시뮬레이션 모델을 PSCAD/EMTDC를 기반으로 구성하고 실제 설치된 풍력발전기의 운전 특성과 비교하였다. 특히, 연계점의 전압변동을 해석적으로 예측하기 위하여 전원측 등가 임피던스와 부하측 등가 임피던스로 구성된 간략화한 모델을 제안하였으며 제안된 방법으로 계산된 전압변동량이 시뮬레이션 및 실측 데이터와 잘 일치하는 것을 확인하였다. 이 결과는 소형 풍력발전기 계통연계 시스템 설계 및 사전검토 단계에서 안정성과 신뢰성을 확보 하기위한 도구로 활용될 수 있다.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.421-423
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• 2003

To prevent fault effect in supply of electric power distribution system and plan stable operation of electric power system, must control magnitude of fault current. Although there are various kinds of method to solvethis, approached from super conductivity Fault Current Limiter application viewpoint among them. High Temperature Superconductor-Fault Current Limiter (HTS-FCL) development is progressing according to HTS technology development, and system application is tried. For actual system application of such super conductivity FCL, so that can reflect special quality of actuality supply of electric power distribution system just as it is in this treatise supply of electric power system by two modelling do. Also, by simulation of HTS-FCL action and protection coordination with another equipment appliances, verified the effectiveness in supply of electric power system applying itself super conductivity FCL EMTDC dynamic characteristic model that is develope.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.63 no.4
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• pp.266-270
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• 2014

In this paper, the effects of superconducting fault current limiter (SFCL) installed in power distribution system on reliability are evaluated and analyzed. The fault current will be decreased in power distribution system with SFCL because of the increased impedance of SFCL. The decreased fault current will improve the voltage drop of the bus of substation. The voltage drop is an important factor of power distribution system reliability. In this paper, improvement of reliability worth is analyzed when SFCLs are installed at the starting point in power distribution system. First, resistor-type SFCL model is used in PSCAD/EMTDC. Next, typical power distribution system is modeled. Finally, when the SFCLs with impedance 0.5 [${\Omega}$] are installed in feeder, power distribution system reliability is evaluated. Also, the improvement effect of reliability worth including the effect of voltage sag is analyzed using customer interruption cost according to whether or not SFCL is installed.

• Journal of Electrical Engineering and Technology
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• v.8 no.2
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• pp.262-270
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• 2013

A boundary protection method for power distribution line based on equivalent boundary effect is presented in this paper. In the proposed scheme, the equivalent resonance component with a certain central frequency is sleeve-mounted at the beginning of protected zone. The 'Line Boundary' is built by using boundary effect, which is created by introducing impedance in the primary-side of line. The 'Line Boundary' is significantly different from line wave impedance. Therefore, the boundary protection principle can be applied to power distribution line without line traps. To analyze the frequency characteristic corresponding to traveling-waves of introducing impedance in the primary-side of line, distributed parameters model of equivalent resonance component is established. The results of PSCAD/EMTDC simulation prove the obvious difference of voltage high frequency component between internal faults and external faults due to equivalent resonance component, and validate the scheme.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.389-391
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• 2005

This paper describes experimental analysis of UPFC, which is composed of cascaded H-bridge modules and single-phase multi-winding transformers for isolation. The operational characteristic was analyzed through experimental works with a scaled model, and simulation results with PSCAD/EMTDC. The UPFC proposed In this paper can be directly connected to the transmission line without series injection transformers. It has flexibility to expand the operation voltage by increasing the number of H-bridge modules. The analysis results can be utilized to design the actual UPFC system applicable for the transmission system.

• Proceedings of the KIEE Conference
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• 2005.10a
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• pp.93-96
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• 2005

This paper describes experimental analysis of UPQC, which is composed of cascaded H-bridges and single-phase multi-winding transformers. The operational characteristic was analyzed through experimental works with a scaled model, and simulations with PSCAD/EMTDC. The UPQC proposed in this paper can be directly connected to the distribution line without series injection transformers. It has flexibility to expand the operation voltage by increasing the number of H-bridge modules. The analysis results can be utilized to design the actual UPQC system applicable for the actual distribution system.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.9
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• pp.422-430
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• 2005

This paper describes experimental analysis of UPFC, which is composed of cascaded H-bridge modules and single-phase multi-winding transformers for isolation. The operational characteristic was analyzed through experimental works with a scaled model, and simulation results with PSCAD/EMTDC. The UPFC proposed in this paper can be directly connected to the transmission line without series injection transformers. It has flexibility to expand the operation voltage by increasing the number of H-bridge modules. The analysis results can be utilized to design the actual WFC system applicable for the transmission system.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.9
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• pp.493-499
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• 2003

This paper presents exact Autotransformers(ATs)-fed AC electric Railroad system modeling using constant current mode for locomotives. An AC electric railroad system is rapidly changing single-phase load, and at a feeding substation, 3-phase electric power is transferred to paired directional single-phase electric power. As the train moves along a section of line between two adjacent ATs. The proposed AC electric railroad system modeling method considers the line self-impedances and mutual-impedances. The constant current mode model objectives are to calculate the catenary and rail voltages with the loop equation. When there are more than one train in the AC electric railroad system, the principle of superposition applies and the only difference between the system analyses for one train. Filially, this paper shows the general equation of an AC electric railroad system, and that equation has no relation with trains number, trains position, and feeding distance.