• Journal of Electrical Engineering and Technology
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• v.12 no.4
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• pp.1586-1592
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• 2017

Voltage sourced converter (VSC) based direct-current (DC) grid has the ability to control power flow flexibly and securely, thus it has become one of the most valid approaches in aspect of large-scale renewable power generation, oceanic island power supply and new urban grid construction. To solve the optimal power flow (OPF) problem in DC grid, an adaptive particle swarm optimization (PSO) algorithm based on fuzzy control theory is proposed in this paper, and the optimal operation considering both power loss and voltage quality is realized. Firstly, the fuzzy membership curve is used to transform two objectives into one, the fitness value of latest step is introduced as input of fuzzy controller to adjust the controlling parameters of PSO dynamically. The proposed strategy was applied in solving the power flow issue in six terminals DC grid model, and corresponding results are presented to verify the effectiveness and feasibility of proposed algorithm.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.16-18
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• 2000

The recent movement to deregulated and competitive electricity market changes the role of Security Constrained Optimal Power Flow (SCOPF) and increases the importance for real-time computation. communication, and on-line data control. As power systems tend to be operated more closely to their ultimate ratings, more rapid updates of telemetered data and faster solutions times are becomimg necessary to better track the changes in systems. This paper presents an on-line SCOPF application exploiting the state-of-art OPF tools and corresponding interfacing technologies. The significance of the proposed mechanism is demonstrated with a case study system.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.855-857
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• 2005

Transmission congestion is one of the Key factor to local market power in competitive electricity markets. Financial transmission rights provide the financial protection to their holders by paying back the congestion cost. However, the market participants who have market power can exacerbate their market power. This paper analyzes the effect of exercising local market power with the rights on the market price. The proposed methodology was demonstrated with the Optimal Power Flow(OPF). Case study is fulfilled by GAMS simulation. The simulation are condusted in case of Nodal Pricing.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.416-417
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• 2006

The recent movement to deregulated and competitive electricity market requires new concepts against existing central dispatch in the system operation and planning. As power systems tend to be operated more closely to their ultimate ratings, the role of SCOPF(Security Constrained Optimal Power Flow) is changed. This paper deals with the proper Unit Commitment condition changed according to the conditions or configuration of power system. This goal of is paper is to obtain proper security and Optimal UC condition through the efficient usage of the sensitivity Factor against critical contingencies. The proposed mechanism has been tested on a sample system and results show more secure conditions against critical contingencies.

• Proceedings of the KIEE Conference
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• 2005.11b
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• pp.159-161
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• 2005

Transmission congestion is one of the key factors to local market power in competitive electricity markets. Financial transmission rights provide the financial protection to their holders by paying back the congestion cost. However, the market participants who have market power can exacerbate their market power. Due to the exacerbated market power, this paper analyzes the mitigation of local market power using Contingent transmission rights on the market price. Contingent transmission rights provide not only the financial protection but also regulative penalty. The proposed methodology was demonstrated with the Optimal Power Flow(OPF).

• Proceedings of the KIEE Conference
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• summer
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• pp.245-247
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• 2004

Stability is an important constraint in powr system operation. A new methodolgy that reduces the need for repeated simulation to determine a transiently secure operating point is presented. at cntingency , critical generator is limited generation to prevent rotor accelation until system is secured. when energy margin is zero, generation is degermined Implementation issues and simulation results are discussed in th context of a 23-bus system

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.11
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• pp.2804-2811
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• 2000

A Nordsick form opf the multirate integration scheme has been proposed for flexible multibody dynamic systems. It is assumed that vibrational modal coordinates in the equations of motion are treated as fast variables, whereas the relative joint coordinates are treated as slow variables. In the multirate integration, the fast variables are integrated with small step-size, and the slow variables are integrated with larger step-size. The proposed multirate integration method is based on the Adams-Bashforth-Moulton predictor-corrector method and implemented in the Nordsieck vector form. The Nordsieck form of multrate integration method provides effective step-size control and at the same time, inherits the efficiency from the Adams integration method. Simulations of a flexible gun and turret system of the military tank have been carried out to show the effectiveness and efficiency of the proposed method.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.2
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• pp.268-276
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• 2007

Transmission congestion is one of the key factors to local market power in competitive electricity markets. Financial transmission rights provide the financial protection to their holders by paying back the congestion rent. A variety researches have shown that the existing trading mechanisms on transmission right can exacerbate market power. This paper proposes an alternative methodology in mitigating the local market power using the Contingent Transmission Rights on the locational marginal pricing scheme. The proposed methodology was demonstrated with the Optimal Power Flow.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.298-299
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• 2008

In this paper, supposed that can measure power quality of bus and can calculate this cost in case electric charges about customer are imposed by each bus. When reflected this in system planning, expected cost proposed following method through sample system. We calculated the nodal cost by OPF(optimal power flow) in system and the drop numbers that happen during year of loads utilizing VSCC. Also calculated BPQC using the disruption numbers. As a result, calculated bus total cost including power quality cost through case study.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.195-196
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• 2015

최근 계절별, 시간대별 전력 수요 패턴의 변화로 계통의 전압 수준을 일정 수준으로 관리하는 것이 어려워지고 있다. 계통 전압이 높으면 작게는 설비 상의 문제부터 크게는 계통 안정도의 문제가 생길 수 있다. 따라서 전압 유지 및 계통 안정도 향상을 위해서 적정한 위치에 조상설비 투입을 고려할 수 있다. 본 논문에서는 기준 전압을 초과하는 모선의 전압을 낮추기 위해 최적의 조상설비 설치 위치 및 용량 산정 방법을 제시한다. 제안된 방법은 2014년 시간대별 데이터를 대상으로 최적조류계산을 수행하여 리액터 용량을 계산하고 경부하시 리액터 투입하는 것이다. 제안된 최적조류계산을 활용한 리액터 설치 지점 및 용량 선정 방안을 검증하기 위하여 국내계통에 대한 시뮬레이션이 수행되었다.