• Transactions on Electrical and Electronic Materials
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• v.18 no.5
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• pp.303-309
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• 2017

The flexible AC transmission system (FACTS) provides a new advanced technology solution to improve the flexibility, controllability, and stability of a power system. The unified power flow controller (UPFC) is outstanding for regulating power flow in the FACTS; it can control the real power, reactive power, and node voltage of distribution networks. This paper investigates the performance of the UPFC for power flow control with a series of step changes in rapid succession in a power system steady state and the response of the UPFC to distribution network faults and islanding mode. Simulation was carried out using the MATLAB's simulink sim power systems toolbox. The results, which were carried out on a 5-bus test system and a 4-bus multi-machine electric power system, show clearly the effectiveness and viability of UPFC in rapid response and independent control of the real and reactive power flows and oscillation damping [6].

• International Journal of Control, Automation, and Systems
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• v.6 no.4
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• pp.495-505
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• 2008

This paper describes modeling Voltage Sourced Inverter (VSI) type Flexible AC Transmission System (FACTS) controllers and control methods for power system dynamic stability studies. The considered FACTS controllers are the Static Compensator (STATCOM), the Static Synchronous Series Compensator (SSSC), and the Unified Power Flow Controller (UPFC). In this paper, these FACTS controllers are derived in the current injection model, and it is applied to the linear and nonlinear analysis algorithm for power system dynamics studies. The parameters of the FACTS controllers are set to damp the inter-area oscillations, and the supplementary damping controllers and its control schemes are proposed to increase damping abilities of the FACTS controllers. For these works, the linear analysis for each FACTS controller with or without damping controller is executed, and the dynamic characteristics of each FACTS controller are analyzed. The results are verified by the nonlinear analysis using the time-domain simulation.

• Proceedings of the KIEE Conference
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• 1997.07f
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• pp.2010-2012
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• 1997

A cascade multilevel voltage source inverter is introduced to apply the advanced static var compensator(ASVC) for large scale power application. This cascade M-level inverter consists of (M-1)/2 single-phase full bridges. This inverter is suitable to the flexible ac transmission systems(FACTS) including SVC, series compensation and phase shifting. It can solve the problems of conventional transformer -based multipulse inverters and multilevel diode-clamped inverters. From the simulation results, the validity of ASVC with cascade multilevel inverter is shown for high power application.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.117_118
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• 2009

송전선 경과지 선정의 어려움과 같은 여러 가지 이유로 송전 설비를 확충하는데 어려움을 겪고 있다. 이에 따라 기존 송전 설비의 활용도를 높이는 방법으로 전력 계통의 신뢰도를 극대화할 필요가 있으며, 최근 이의 한 방편으로, 전력공급의 유연성 및 신뢰성을 확보할 수 있는 송전기술인 유연송전시스템(FACTS: Flexible AC Transmission System)이 사용되고 있다. 본 논문에서는 유연송전시스템을 포함한 전력계통의 모델을 설정하고, 이를 포함한 전력�墳育� 상태추정을 수행하였다. 개발된 프로그램은 6모선 시험계통을 이용하여 타당성을 검증하였다.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.332-334
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• 2005

This paper presents a dynamic simulation of the unified power flow controller (UPFC) using a current injection method. Flexible AC Transmission System (FACTS) devices give more flexibility of control for security and economic operation of power systems. Diffculties of modeling UPFC in the conventional dynamic simulation programs arise from the fact that the injected voltage by the series inverter is superimposed on the shunt inverter side voltage. A solution can be a current injection method, in which a serial part of UPFC is converted to a parallel equivalent circuit using source transformation, and two current sources affect each other at every time step. To verify efficiency of this method, the proposed model is applied for the transient analysis of an example power system.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.201-202
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• 2015

전력계통이 대형화, 복잡화됨에 따라 현재의 전력전송은 한계 전송량에 가깝게 운영되고 있다. 또한 정치적, 경제적, 사회적 수용성 등의 이유로 전력을 융통하기 위한 신규 초고압 송전선로의 건설도 어려운 실정이다. 이 때 루트 송전선로의 탈락은 계통의 과도안정도에 큰 영향을 끼칠 수 있으며, 발전기 탈락을 통하여 계통을 안정화 시킬 수 있다. 하지만 과도한 발전기 탈락은 계통의 신뢰성 있는 운영에 방해물이 될 수 있다. 유연송전기기(FACTS, Flexible AC Transmission Systems)는 이러한 루트 선로 탈락에 따른 발전기 탈락을 최소화 할 수 있다. 본 논문에서는 FACTS의 한 종류인 STATCOM(Static Synchronous Compensator)을 이용하여 사고 시, FACTS 기기 설치 유무에 따른 과도안정도 분석을 진행한다.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.1925-1927
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• 1998

D-STATCON using the multilevel voltage source inverters is presented for voltage regulation and reactive power compensation in distribution system. This cascade M-level inverter consists of (M-1)/2 single phase full bridge inverter(FBI). This multilevel inverter is a natural fit to the flexible ac transmission systems(FACTS) including STATCON, SVC, series compensation and phase shifting, It can solve the problems of conventional transformer-based multipulse inverters and multilevel diode-clamped inverters. From the simulation results, the superiority of D-STATCON with cascade multilevel inverter is shown for high power application.

• KIEE International Transactions on Power Engineering
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• v.4A no.4
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• pp.192-200
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• 2004

This paper evaluates FACTS control on the available transfer capability (ATC) enhancement. Technical merits of FACTS technology on boosting ATC are analyzed. More effective control means for line flow and bus voltage require the application of FACTS. In this paper, the power flow calculation method for the power systems with FACTS is based on the current injection model (CIM) and the Newton-Raphson method. An integrated scheme for ATC calculation, which considers the dynamic characteristic of the power system, is suggested. The study is applied to the IEEE 57-bus power system to demonstrate the effectiveness of FACTS control on ATC enhancement.

• Proceedings of the KIEE Conference
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• 1996.11a
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• pp.332-335
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• 1996

Multilevel voltage source inverters are emerging as a new breed of power inverter options for high power applications. This paper presents a cascade typed multilevel voltage source inverter which has separate de sources for high voltage. This inverter is proposed for flexible ac transmission systems (FACTS) including static var compensator(SVC), series compensation and phase shifting. It can solve the problems of conventional transformer-based multipulse inverters and the problems of multilevel diode-clamped inverters. To show the superiority of multilevel cascaded inverter, simulation results are discussed in detail.

• Journal of Electrical Engineering and Technology
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• v.5 no.1
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• pp.79-102
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• 2010

This paper presents exhaustive review of various methods/techniques for coordinated control between FACTS controllers in multi-machine power systems. It also reviews various techniques/methods for optimal choice and allocation of FACTS controllers. Authors strongly believe that this survey article will be very much useful to the researchers for finding out the relevant references in the field of placement and coordination of FACTS Controllers.