• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.1153-1155
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• 1997

Electric business all over the world is dramatically changed from vertically integrated monopoly to competition systems. Also, independent power producers(IPPs) will start their commercial operation from the year 2001 in Korea. In this regard, determination of the transaction cost between IPPs and electric utilities will be a hot issue, and electric utilities requires a new framework to support their decision-making. This paper presents the concept of the avoided cost which can be used for economic studies. This paper also describes a novel algorithm to evaluate the avoided cost of a IPP. The case studies are performed on the basis of the official generation expansion plan of Korea by using the Wien Automatic System Planning Package(WASP).

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.772-774
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• 2005

Interstate electric power system, as an alternative for energy cooperation under regional economic bloc, has been hotly debated before progressing the restructure in electric power industry and rapidly expanded in many regions after 1990s. Especially, since northeast asia has strong supplementation in resource, load shape, fuel mix etc., electric power system interconnection in this region may bring considerable economic benefits. Moreover, since Korean electric power system has a great difficulty in a geographical condition to interrupt electricity transaction with other countries, it has been expanded as an independent system to supply all demand domestically. As a result, Korean electric power system makes considerable payment for maintaining system security and reliability and expands costly facilities to supply a temporary summer peak demand. Under this inefficiency, if there are electricity transactions with Russia via the North Korea route then economic electric power system operation may be achieved using seasonal and hourly differences in electricity price and/or load pattern among these countries. In this paper, we estimate price cap of transacted electricity via interstate electric power system in northeast asia. For this study, we perform quantitative economic analysis on various system interconnection scenarios.

• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.1149-1152
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• 1997

This paper describes a novel approach for allocating transmission costs among users of transmission services. In the suggested approach, the cost share of each participant is proportional to amount of its line flow. To develop individual user's impact, the line utilization factors of each participant are derived by power flow equations of all nodes (i.e., load-flow equations). To deal With the slack bus problem inherent in the conventional load-flow analysis more practically, a additional power supply/demand balance equation is incorporated. Although the developed allocation rule is basically similar to the existing MW-mile method in the aspect of embedded cost allocation, it does not require to get load flow solutions of each wheeling transaction when multiple transmission transactions are considered.

• Journal of Electrical Engineering and Technology
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• v.2 no.2
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• pp.194-200
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• 2007

The deregulation problem has recently attracted attentions in a competitive electric power market, where the cost must be earmarked fairly and precisely for the customers and the Independent Power Producers (IPPs) as well. Transmission loss is an one of several important factors that determines power transmission cost. Because the cost caused by transmission losses is about $3{\sim}5%$, it is important to allocate transmission losses into each bus in a power system. This paper presents the new algorithm to allocate transmission losses based on an integration method using the loss sensitivity. It provides the buswise incremental transmission losses through the calculation of load ratios considering the transaction strategy of an overall system. The performance of the proposed algorithm is evaluated by the case studies carried out on the WSCC 9-bus and IEEE 14-bus systems.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.7
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• pp.311-316
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• 2002

It has been a basic model for the present electric power industry that more than two generators compete, and thereby the market clearing price and the generation schedules are determined through the bid process. In order for this paradigm to be applicable to real electric power systems and markets, it is necessary to reflect many physical and economic constraints related to frequency and transmission in the dispatching schedule. The paper presents an approach to deriving a Nash bargaining solution in a competitive electricity market where multiple generators are playing with the system operator who mitigates the transmission congestion to minimize the total transaction cost. In this study, we take the effect of the line flows and the role of system operator into the Game. Finally, a case study has been demonstrated to verify the proposed cooperative game.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.4B no.4
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• pp.157-169
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• 2004

Motor & generator operation at widely variable speeds is needed in various applications but hybrid and electric vehicle (HEV) stand out today, as quite a few companies are launching this year their mass production of HEVs. The quest for better starter-generators is far from ended, though. The present review paper unfolds a comparative critical evaluation of various starter-generators and their control for HEV. Induction, interior PM synchronous, transverse-flux PM synchronous, switched reluctance, together with claw-pole and biaxial excitation PM synchronous (BEGA) configurations with their control are all considered in system evaluations.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.5B no.1
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• pp.1-5
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• 2005

The vector magnetic property is defined as the relationship between the magnetic field strength vector H and the magnetic flux density vector B. It is very important for the development of high efficiency and the high-density electric machines. The electrical steel sheet for the machine core shows the remarkable vector behavior by the high magnetic flux density level. In this paper, the magnetic characteristic analysis using E&S2 model is introduced as the useful technology for the design and development.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.57-59
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• 2005

This paper describes the applicability of HVDC system to KEPCO system in terms of educing short circuit current. Especially, the effect of reducing the short circuit current n Gyungin area and Seoul area by using HVDC system was mainly investigated. In addition, the transaction of electric power between ar was, security problem, and economic aspects were also examined.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.12B no.1
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• pp.7-12
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• 2002

This paper presents a method to estimate an effective length of a 1000-kVA superconducting generator using three-dimensional FE analysis. Flux linkage of stator coil and the induced voltage are calculated with FEM program and Faraday's law. An effective length of the stator coil is estimated using the calculated voltage and geometric configurationn of the machine. In order to verify the estimation method, 30-kVA superconducting generator is built and tested. The test result agrees reasonably well with the estimation.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.5B no.2
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• pp.181-188
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• 2005

In this paper, a DC smoothing filterless soft switching pulse modulated high frequency AC power conversion circuit connected to utility. frequency AC power source is proposed for consumer induction heating hot water producer, steamer and super heated steamer. The operating principle of DC link filterless utility frequency AC-high frequency AC (HF AC) power conversion circuit defined as high frequency cycloinverter is described, which can operate under a principle of ZVS/AVT and power regulation based on alternate asymmetrical PWM in synchronization with the utility frequency single phase AC positive or negative half wave voltage. The dual mode modulation control scheme based on high frequency PWM and commercial frequency AC voltage PDM for the proposed high frequency cycloinverter are discussed to enlarge its soft switching commutation operating range for wide HF AC power regulation. This high frequency cycloinverter is developed for high frequency IH Dual Packs Heater (DPH) type boiler used in consumer and industrial fluid pipeline systems. Based on the experiment and simulation results, this high frequency cycloinverter is proved to be suitable for the consumer use IH-DPH boiler and hot water producers. The cycloinverter power regulation and power conversion efficiency characteristics are evaluated and discussed.