• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.6
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• pp.1097-1102
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• 2011

This paper proposes the registration information, the participation information for classifying demand resources participate in demand response program. Modeling demand resources from them, it evaluates values of demand resources. Specially assuming that ignore the loss in power system, they take a role as generation. This paper proposes how to evaluate demand resources' values. Case study shows that demand response operators schedule efficiently demand response program by using index of such as the registration information the participation information of demand resource.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.593_594
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• 2009

발전기 기동정지 계획은 다수의 발전기의 운영에서 비용을 최소화할 수 있는 기동 및 정지 시간을 결정하는 것이다. 대규모의 계통에서의 기동정지계획은 복잡한 계통 및 발전기 특성 제약이 시계열적으로 작용하기 때문에 최적화 분야에서도 어려운 문제에 해당한다. 더욱이 최근 증가하는 풍력발전원은 그 출력이 풍속에 따라 시시각각 변동하기 때문에 기동정지계획에서 함께 고려되는 것이 힘들었다. 본 논문은 이러한 풍력발전 출력의 불확실성을 랜덤발생하여 기댓값을 최적화하는 발전기 기동정지계획을 통해 풍력발전원이 기동정지계획에 미치는 영향을 분석하였다. 제시하는 방법으로 모의계통의 사례연구를 통해 유용성을 입증하였다.

• IE interfaces
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• v.23 no.2
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• pp.139-146
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• 2010

In this paper, we present the study of a real passenger transportation system. Passenger transportation problem aims to transport passengers from bus stops to their destinations by a fleet of vehicles while satisfying various constraints such as vehicle capacity, maximum allowable riding time in a bus, and time windows at destinations. Our problem also has special issues such as mixed loading, consideration of afternoon problem together with morning problem, and transferring passengers between vehicles. Our solution approach consists of three serial procedures: bus route generation, bus scheduling, and post optimization. Efficient heuristic algorithms were developed and implemented for the procedures. The proposed solution approach has been successfully applied to several real world problem instances and could reduce about 10% to 15% of buses.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.5
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• pp.929-935
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• 2011

Customers hardly change to electric prices in old days because electricity is essential commodity, while demand changes with price after deregulation. It's explained by price-based demand response with demand-elasticity matrix. Also all of the customers have had identical demand-price elasticity matrix till now. But in a practical power system, various customers are present with taking a variety of demand-price elasticity. Therefore this paper proposes demand-price sensitivity to represent different demand-price elasticity. Also as proposing demand-reliability sensitivity, it is modeling various customers' characteristics to reliability. And then this paper calculates total expected interruption cost of customer from the customer interruption cost and the demand-reliability sensitivity. A total expected interruption cost of system is shown as opportunity cost of a generation cost.

• IE interfaces
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• v.10 no.1
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• pp.189-207
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• 1997

This paper explains a way of describing the erection sequence using the connecting relationship among blocks of a hull in shipbuilding industry. The information of the adjacent blocks such as upper, lower, right, left, front, rear, and their erection status, etd., is defined and the proper use of this allows us to determine one of the possible erection sequences. The methodology suggested also includes some useful benefits of avoiding insert blocks or maintaining stability in erection process. Further, an algorithm for generating the initial erection network is shown and this network may be a basis for designing daily erection scheduling. Some examples illustrate the procedure developed in this study and the results support the model's fidelity.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.328-333
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• 2007

Traditional maintenance planning is based on a constant maintenance interval for equipment life. In order to consider economic aspect for tm based preventive maintenance, preventive maintenance is desirable to be scheduled by RCM(Reliability-Centered Maintenance) evaluation. The main objective of RCM is to reduce the maintenance cost, by focusing on the most important functions of the system and avoiding or removing maintenance actions that are not strictly necessary. So, Markov state model is utilized considering stochastic state in RCM In this paper, a Markov state model much can be used for scheduling and optimization of maintenance is presented. The deterioration process of system condition is modeled by the stepwise Markov model in detail. Also, because the system is not continuously monitored, the inspection is considered. In case study, simulation results about RCM will be shown using the real historical data of combustion turbine generating unit in Korean power systems.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.194-195
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• 2006

미래의 전력 시스템은 환경과 기술적인 이유로 인해 더욱더 많은 분산전원을 이용하게 될 것이다. 분산전원은 서로 다른 특징을 가지고 있고 또한 배전계통에서 기존의 계통운영과는 다른 형태로 운전될 것이다. 이런 관점에서 다수의 분산전원을 모아 하나의 가상의 발전소로 운영하는 개념이 등장하게 되었는데, 이를 Virtual Power Plant(VPP)라고 한다. VPP는 매니지먼트 시스템이 관리하는 여러 클러스터들로 이루어져 있으며 이들 클러스터들은 각각 여러 종류의 분산전원으로 구성되어 있다. 본 논문에서는 클러스터를 이루는 분산전원을 어떻게 운영하는 것이 최적의 경제적 효율을 지닐 수 있을 지에 대해 논의하게 될 것이다. 디젤 발전기의 출력의 경우 그 소유자에 의해 제어가 가능하지만, 태양광 발전 시스템의 경우 기상 상태에 따라 그 출력이 결정된다. 따라서 이러한 각각의 특성을 고려하여 본 논문에서는 디젤, CHP(Combined Heat and Power), 보일러, 태양광발전으로 구성된 복합 시스템에서 각 시간별로 수용가의 전력 및 열 수요와 분산전원의 에너지 생산을 비교하여 VPP 최적 운영 계획을 구성하였다.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.410-411
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• 2006

This paper is focused on the survey on the power system modeling using a clustering algorithm. In electricity markets, clustering method is a efficient tool to model the power system. It can be seen that electricity markets can also be classified into several groups which show similar patterns and that the fundamental characteristics of power systems can be widely applicable to other technical problems in power system such as generation scheduling, power flow analysis, short-term load forecasting, and so on. There are several researches on the power system modeling using a clustering algorithm. We specially surveyed their own clustering methods to model the power system.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.501-504
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• 2004

There is a world-wide trend to implement autonomous TM/TC system in satellite operations. KARI developed CALS(Command AutoLoader System) for KOMPSAT-1 operation automation in 2004. This paper provides system requirement, system design, system test and operational procedure. Through test with simulator and KOMPSAT-1, CALS was verified to meet all functional and operational requirement like scheduling, real-time telemetry check, CRC generation, command grouping. CALS is expected to be used in KOMPSAT-1 normal mission operation in end of 2004

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1270-1272
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• 1999

The generator cost function is one of the basic data for the generation scheduling. Generally the cost functions are obtained form design calculations or from heat rate tests. The real operating condition may be different from the condition of design or the tests. Some of the conditions may not be tested during the periodical maintenance. In order to improve the calculation of the generator cost function, this paper presents a new calculation method of the generator cost functions using the utilization factors of generators and the mixed fuel burning ratio of the generators.