• KIEE International Transactions on Power Engineering
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• 제5A권4호
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• pp.416-424
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• 2005

At present, the Korean electricity industry is undergoing restructuring and the Cost Based-generation Pool (CBP) market is being operated in preparation of a Two Way Bidding Pool (TWBP) market. In deregulated electricity industries, an integrated power market simulator is one of the tools that can be used by market participants and market operators analyzing market behaviors and studying market structures and market codes. In this regard, it is very important to develop an electricity market simulator that reflects market code providing a market operation mechanism. This paper presents the development of an integrated market simulator, called the Power Exchange Simulator (PEXSIM), which is designed to imitate the Korean electricity market considering the various features of the market operating mechanism such as uniform price and constrained on/off payment. The PEXSIM is developed in VB.NET and composed of five modules whose titles are M-SIM, P-SIM, O-SIM, T-SIM and G-SIM interfacing the Access database program. To verify the features and the performance of the PEXSIM, a small Two Way bidding market with a 12-bus system and a One Way bidding market for generator competition will be presented for the electricity market simulations using PEXSIM.

• Journal of Electrical Engineering and Technology
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• 제5권4호
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• pp.530-537
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• 2010

By development of renewable energy and more efficient facilities in an increasingly deregulated electricity market, the operation cost of distributed generation (DG) is becoming more competitive. International environmental regulations of the leaking carbon become effective to reinforce global efforts for a low-carbon paradigm. Through increased DG, operators of DG are able to supply electric power to customers who are connected directly to DG as well as loads that are connected to entire network. In this situation, a community energy system (CES) with DGs is a new participant in the energy market. DG's purchase price from the market is different from the DG's sales price to the market due to transmission service charges and other costs. Therefore, CES who owns DGs has to control the produced electric power per hourly period in order to maximize profit. Considering the international environment regulations, CE will be an important element to decide the marginal cost of generators as well as the classified fuel unit cost and unit's efficiency. This paper introduces the optimal operation of CES's DG connected to the distribution network considering CE. The purpose of optimization is to maximize the profit of CES. A Particle Swarm Optimization (PSO) will be used to solve this complicated problem. The optimal operation of DG represented in this paper would guide CES and system operators in determining the decision making criteria.

• 에너지공학
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• 제13권1호
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• pp.60-67
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• 2004

규제완화된 경쟁적 전력시장으로의 이행은 전력계통의 운영 및 계획에 있어서 기존의 중앙급전방식과는 다른 새로운 개념을 필요로 하고 있다. 경쟁적 전력시장에서의 전력계통 운영은 경제적 측면을 충분히 고려하여 보다 적은 여유로 운영될 것으로 예상된다. 따라서 SCOPF(Security Constrained Optimal Power Flow서 역할이 커지면서 실시간 안전도 처리에 대한 중요성이 보다 부각되고 있다. 본 논문은 On-Line 상의 적용을 가능하게 하는 SCOP떠 응용을 다룬다. 전력계통의 안전도 여유는 계통의 조건과 부하상황에 따라 시시각각 변화한다. 따라서 안전도 처리를 위한 민감도 계수 역시 전력계통 상태에 따라 재계산되고 적용 시에 갱신 처리되어야 한다. 본 논문의 목적은 안전도 처리를 위한 민감도 계수의 효율적인 사용을 통해 적정 안전도를 확보하여 이 알고리즘을 계통운영상에 실시간으로 적용 가능토록 하기 위함이다. 사례연구에서는 제안된 메커니즘을 간단한 예제계통에 적용하여, 상정사고에 대한 보다 안정적인 결과가 나타남을 보였다.

• 조명전기설비학회논문지
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• 제18권6호
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• pp.114-120
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• 2004

본 논문은 전력산업이 경쟁체제로 전환되어 전력시장으로 운영될 경우 보조서비스의 하나인 유효전력손실 배분에 관한 것으로 손실배분계수를 이용하여 유효전력 손실을 부하에 배분하는 방법을 제안하며 아울러 제안하는 방법을 한계손실계수를 이용하는 방법과 비교하고자 한다. 제안하는 방법은 먼저 손실배분계수를 정의하며 이것을 이용하여 유효전력 손실에 대한 각 부하의 분담분을 계산한다. 9-모선 샘플시스템에 대한 사례연구를 통하여 제안하는 알고리즘의 효용성을 입증하고 있으며 한계손실계수를 이용하는 것보다 손실배분계수를 이용하여 유효전력손실을 부하에 배분하는 것이 타당하다는 주장을 담고 있다.

• Journal of Electrical Engineering and Technology
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• 제6권1호
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• pp.14-24
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• 2011

In order to facilitate the electricity market operation and trade in the restructured environment, ample transmission capability should be provided to satisfy the demand of increasing power transactions. The conflict of this requirement and the restrictions on the transmission expansion in the restructured electricity market has motivated the development of methodologies to enhance the available transfer capability (ATC) of existing transmission grids. The insertion of flexible AC transmission System (FACTS) devices in electrical systems seems to be a promising strategy to enhance single area ATC and multi-area ATC. In this paper, the viability and technical merits of boosting single area ATC and multi-area ATC using Thyristor controlled series compensator (TCSC), static VAR compensator (SVC) and unified power flow controller (UPFC) in single device and multi-type three similar and different device combinations are analyzed. Particle swarm optimization (PSO) algorithm is employed to obtain the optimal settings of FACTS devices. The installation cost is also calculated. The study has been carried out on IEEE 30 bus and IEEE 118 bus systems for the selected bilateral, multilateral and area wise transactions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전력기술부문
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• pp.372-374
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• 2006

This paper presents a methodology to predict a failure probability related to the aging generating units in Korea power system. Each generator is represented by a combined reliability model of its individual components, which is determined by failure data. The Weibull distribution is used to calculate failure probability and its parameters are obtained from Type II Censoring. Consequently, the proposed methods would likely to permit utilities to reduce overall costs in the new deregulated environment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전력기술부문
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• pp.234-236
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• 2005

The importance and necessity conducting studios on grid reliability evaluation have been increasingly important In recent years due to the number of black-out events occurring through in the world. Quantity evaluation of transmission system reliability is very important in a competitive electricity environment. The reason is that the successful operation of electric power under a deregulated electricity market depends on transmission system reliability management. Also in Korea it takes places. The results of many case studios fer the KEPCO system using the Transmission Reliability Evaluation for Large-Scale Systems (TRELSS) Version 6_2, a program developed by EPRI are introduced in this paper. Some sensitivity analysis has been Included in case study. This paper suggests that the some Important input parameters of the TRELSS can be determined optimally from this sensitivity analysis fer high reliability level operation of a system.

• 한국시스템다이내믹스연구
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• 제3권1호
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• pp.43-60
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• 2002

This paper describes the forecast of wholesale price in competitive Korean electricity market using the system dynamics approach. The system dynamics concepts have been implemented with the Ithink software. This software facilitates the development of stock and flow model with information feedback. Using this model, the future wholesale electricity price can be computed hour by hour, quarterly, and yearly. This model also gives the energy planner the opportunity to create different scenarios for the future of deregulated wholesale markets in Korea. Also It will lead to increased understanding of competitive wholesale market as a complex, dynamic system. Research results show that the plant construction appeared in waves of boom and bust in Korean electricity market like real estate construction. That is, the Korea wholesale market's new power plants and the market price will appear the Boom and Bust cycle. It is very similar behavior as real estate industry. In case of consideration of DSM program, The DSM savings lead to a somewhat different timing of the booms in construction and of price spikes. But the DSM programs do not eliminated the fundamental dynamics of the boom and bust. And the wholesale price is maintained at the lower level compared to the case of without DSM program. However, the unexpected result is found that due to the lower market price, Investor make significantly less investment in new CCs, which leads to the higher wholesale price after 2010. It suggests that the DSM Policy must be implemented with the dynamics of competitive Electricity Market.

• 전기학회논문지
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• 제58권2호
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• pp.256-263
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• 2009

For the power system to keep in a stable operating state, sufficient ancillary services must be available to respond to credible contingency events and return the power system to a satisfactory operating state in the case of contingencies as well as blackout events within specified predefined limits. The logical and reasonable bases of valuing and pricing the ancillary services are required to reach the common ground among market participants. The total amount of black start service transactions is quite small compared to the total ancillary service transactions as well as energy market transactions. Black start services must be provided as one of the ancillary services in the deregulated electricity market. In order to procure and remunerate black start services, it is necessary to quantify the value of the black start sources within the power system. In this paper, an approach to assess the value of the black start service is presented based on the cost-of-service solution. Financial simulation of the influence on market participants for the proposed approach on the service is carried out. The cost of the black start service is allocated in accordance with the principle of "causer pays", and the cost is shared by the producers and consumers equally that created the requirement for the service. Under the present electricity market, the mechanism to recover the cost is not implemented, a new approach to the ancillary services to provide incentive for the service providers has to be studied in the near future.

• International Journal of Control, Automation, and Systems
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• 제6권5호
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• pp.639-650
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• 2008

Electricity price forecasting has become an integral part of power system operation and control. In this paper, a wavelet transform (WT) based neural network (NN) model to forecast price profile in a deregulated electricity market has been presented. The historical price data has been decomposed into wavelet domain constitutive sub series using WT and then combined with the other time domain variables to form the set of input variables for the proposed forecasting model. The behavior of the wavelet domain constitutive series has been studied based on statistical analysis. It has been observed that forecasting accuracy can be improved by the use of WT in a forecasting model. Multi-scale analysis from one to seven levels of decomposition has been performed and the empirical evidence suggests that accuracy improvement is highest at third level of decomposition. Forecasting performance of the proposed model has been compared with (i) a heuristic technique, (ii) a simulation model used by Ontario's Independent Electricity System Operator (IESO), (iii) a Multiple Linear Regression (MLR) model, (iv) NN model, (v) Auto Regressive Integrated Moving Average (ARIMA) model, (vi) Dynamic Regression (DR) model, and (vii) Transfer Function (TF) model. Forecasting results show that the performance of the proposed WT based NN model is satisfactory and it can be used by the participants to respond properly as it predicts price before closing of window for submission of initial bids.