• Proceedings of the KIEE Conference
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• summer
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• pp.310-312
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• 2004

Generally, instrument transformer of the core type have been used for measuring current. Because instrument transformer has defects, electronic instrument was appeasred. This paper is introduced a basic concept and thoery of electronic instrument and described the the simulation of core type CT and no saturation CT. The evaluation of CT models implemented using EMTP(Electro Magnetic Transients Program) was carried out. The result of comparison both core type CT and no saturation CT are presented.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.7
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• pp.1199-1205
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• 2010

The recent power system is required to a large size of facilities and high power technology according to increasing power demand. However, it could lead to spoiling the beauty of city and environment problem. The miniaturized facilities with large capacity such as GIS have been required in recent power system. The GIS(Gas Insulated Substation) using the SF6 insulation gas enables to miniaturize facilities with large capacity with high insulation performance. However, the substation installed GIS has required to new design model which is different from the conventional substation. The TRV(Transient Recovery Voltage) analysis on simple circuit may applied by differential equation. However, in case of relatively complicated system, EMTP(Electro Magnetic Transients Program) mainly has been used to design and simulate for transient analysis. This paper mainly design the 22.9 kV GIS system and analyze the transient recovery voltage of main circuit breaker using EMTP/RV. It also enables to easily design the other substation installed GIS with same maker and voltage level because the proposed GIS model consists of separated modules such as busbar, circuit breaker, bushing, CT, PT etc. Eventually, it contributes to comfortably compare the interrupting performance of circuit breaker and system TRV corresponding to the substation system configuration.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.221_222
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• 2009

최근 전력 컨버터 사용의 증가로 배전계통에서의 고조파 왜곡이 날로 심각해지고, 따라서 고조파에 민감한 전력계통 기기와 고객 부하를 보호하기 위한 고조파 저감대책이 필요하다. 본 논문에서는 능동 필터와 Low-Pass Filter(LPF)를 전력계통 과도해석 프로그램인 Electro-Magnetic Transients Program(EMTP) 내의 Transients Analysis of Control Systems(TACS) 소자를 사용하여 모델링하고 고조파 발생시 능동필터에 LPF의 설치 유/무에 따른 배전계통에서의 상전류와 중성선 전류의 변화를 분석하였다.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.539-545
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• 2001

This paper proposes a static synchronous series compensator based on multi-bridge inverter. The proposed system consists of 6 H-bridge modules per phase, which generate 13 pulses for each half period of power frequency. The dynamic characteristic was analyzed by simulations with EMTP code, assuming that it is inserted in the 154-kV transmission line of one-machine-infinite-bus power system. The feasibility of hardware implementation was verified through experimental works using a scaled model. The proposed system does not require a coupling transformer for voltage injection, and has flexibility in expanding the operation voltage by increasing the number of H-bridge modules.

• Journal of Power Electronics
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• v.1 no.1
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• pp.48-55
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• 2001

This paper describes a switching-level simulation model and scaled hardware model for SSSC, which is useful for analyzing the dynamic interaction between the SSC and the power transmission system. A detailed simulation model with EMTP was developed to verity the SSSC operation with control system, and its increasing capability of power transmission through the line for a typical one-machine infinite-bus system. The simulation results of the developed model are compared with the experimental results froma scaled model fo 2KVA rating for evaluation the whole system operation.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.10
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• pp.1688-1695
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• 2008

Recently, it is common in a distribution system of Korea Electric Power Corporation (KEPCO) to find instances where distribution lines are parallel. A traditional method of an induced voltage calculation is not suitable for parallel distribution lines. For more actual analysis of induced voltage on telecommunication lines in parallel distribution lines, a new calculation method is needed. This paper presents a new calculation method of an induced voltage on telecommunication line using equivalent ${\pi}$ circuits matrix in parallel distribution lines. The advantages of the calculation method are using actual neutral current value and not using screening factor for considering the overhead ground wire and the neutral wire. To verify the effectiveness and the accuracy of the method, various case studies are performed with EMTP(Electro-Magnetic Transients Program).

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.3
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• pp.450-454
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• 2009

This paper analyzes a asymmetry current with SFCL (Superconducting Fault Current Limiter) operation during transient period, when a fault occurs in power systems. The principle of asymmetry current nature is reviewed and asymmetry components reduction with SFCL operation is explained. To verify the performance of SFCL, a EMTP/ATPDraw model of SFCLs using MODELS language developed and simulated. Throughout the simulation, results presents the main factors for reducing the asymmetry component of fault current are not a quenching time, but a limiting resistance of SFCL and fault initiated angle.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.486-487
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• 2008

최근 전력수요의 증가에 따른 대규모 발전 설비 건설의 어려움과 매장자원의 고갈 등 여러 가지 문제가 부각되고 있는 시점에서 에너지원의 다양화와 전력수급의 장기적인 안정성 확보는 중요한 문제로 부각되고 있다. 특히 환경보호 문제 및 산업발전에 따른 수용가에 양질의 전력을 공급하기 위하여 고신뢰 고품질의 유연배전계통의 구성이 요구되고 있는 시점에서 마이크로그리드의 도입과 관련된 많은 연구가 필요하다. 이 논문에서는 마이크로그리드의 운전형태에 따른 인버터기반의 마이크로소스의 동특성을 알아보기 위하여 EMTP(Electro Magnetic Transients Program)를 이용하여 마이크로소스의 모델링 및 시뮬레이션을 하였다.

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.398-403
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• 1998

This paper describes a controller design for the stator reactive power generator in the transmission system. The controller of static reactive power generator was designed using a mathematical model and non-linear state feedback. The performance of controller was verified using computer simulation with EMTP code and experimental work with scaled-model. The dynamic interaction with a simple power system was also analyzed using both the simulation model and hardware scaled-model. Both simulation and experimental results prove that the controller using PI block and non-linear state feedback offers better performance than the controller using PI block only.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.6
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• pp.296-302
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• 2001

This paper proposes a SSSC based on multi-bridge inverters. The dynamic characteristic of the proposed SSSC was analyzed by EMTP simulation and a scaled hardware model, assuming that the SSSC is inserted in the transmission line of the one-machine-infinite-bus power system. The proposed SSSC has 6 multi-bridge inverters per phase, which generates 13 pulses for each half period of power frequency. The proposed SSSC generates a quasi-sinusoidal output voltage by 90 degree phase shift to the line current. The proposed SSSC does not require the coupling transformer for voltage injection, and has a flexibility in operation voltage by increasing the number of series connection.