• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.8
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• pp.1172-1180
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• 2017

This study analyzed competition in peak load plants between CCGT and GT instead of competition between base and peak load plants like in previous studies. In common overseas power markets, CCGT and GT claim certain market shares as peak load plants with the latter boasting a high utilization rate as reserve plants. In South Korea, however, there has been no introduction of GT in the market that opened in 2001 with no analysis cases of GT's economy as a peak load plant. The current power market of South Korea is run on the cost-based pool, which allows for no price spikes. Since the capacity payment criteria for compensations for missing money are set based on GT generators, the power market uses GT generators as marginal plants. The purposes of this study were to analyze the competitive edge of GT generators as peak load plants in the domestic power market of South Korea and identify the causes of GT's failure in market entry, thus assessing the adequacy of market signals in the domestic power market.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.869-871
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• 2005

As deregulated electricity markets are being implemented in different countries, the remuneration of reactive power which contribute to ancillary services is one of the key issues, so it is necessary to evaluate the generator's reactive. In this paper, we focus on the evaluation of reactive power which contributes to reactive power balance. The idea is that the main usages of the reactive power of generator can be divided into two components. First one is physically required amounts for transmitting the real power and the second one is the amounts contributed to support the system, that is, to maintain the voltage profiles. In this paper, the second component is used to evaluate the effective amounts of the reactive power contributed to ancillary service.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.67 no.2
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• pp.112-118
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• 2018

In recent years, decentralized power have been increasing due to environmental problems, liberalization of electricity markets and technological developments. These changes have led to the evolution of power generation, transmission, and distribution into discrete sectors and the division of integrated power systems. Therefore, studies are underway to efficiently supply power and reduce losses to each sector's demand. This is a major concern for system planners and operators, as it accounts for a relatively high proportion of total power, with a transmission and distribution loss of 4-6%. Therefore, this paper analyzes the status of loss management based on the current transmission and distribution loss rate of each country and transmission loss management cases of each national power company, and proposes a loss rate prediction algorithm according to the long-term transmission system plan. The proposed algorithm predicts the demand-based long-term evolution and the loss rate of the grid to which the transmission plan is applied.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.1
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• pp.38-42
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• 2005

Restructuring of the electric power industry has brought the issue of market competitiveness to surface. Recent years have witnessed the appearance of a particular seller or group of sellers exercising market power in electricity supply. In fact, much scholarly work has been done on how to identify and mitigate such abuse by market management rules. In this paper we assess the possible market power on the basis of pivotal supplier test and propose the method to determine the reasonable quantity of long-term contracts which can play a crucial role in mitigating the market power for a pivotal player. Furthermore the market efficiency is guaranteed by making long term contracts with a pivotal player up to the quantity to ensure that the pivotal player has no incentive to abuse the pivotal quantity in the electricity market.

• KIEE International Transactions on Power Engineering
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• v.4A no.4
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• pp.262-267
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• 2004

With the advent of electric power systems moving from a vertically integrated structure to a deregulated environment, calculating reactive power service charges has become a new and challenging theme for market operators. This paper examines various methods for reactive power management adopted throughout various deregulated foreign and domestic markets and then proposes an innovative method to calculate reactive power service charges using a reactive power market in a wholesale electricity market. The reactive power market is operated based on bids from the generating sources and it settles on uniform prices by running the reactive OPF programs of the day-ahead electricity market. The proposed method takes into account recovering not only the costs of installed capacity but also the lost opportunity costs incurred by reducing active power output to increase reactive power production. Based on the result of the reactive OPF program, the generators that produce reactive power within the obligatory range do not make payments whereas the generators producing reactive power beyond the obligatory range receive compensation by the price determined in the market. A numerical sample study is carried out to illustrate the processes and appropriateness of the proposed method.

• International Journal of Fluid Machinery and Systems
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• v.9 no.2
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• pp.182-193
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• 2016

Introduction of intermittent electricity production systems like wind and solar power to electricity market together with the deregulation of electricity markets resulted in numerous start/stops, load variations and off-design operation of water turbines. Hydraulic turbines suffer from the varying loads exerted on their stationary and rotating parts during load variations since they are not designed for such operating conditions. Investigations on part load operation of single regulated turbines, i.e., Francis and propeller, proved the formation of a rotating vortex rope (RVR) in the draft tube. The RVR induces pressure pulsations in the axial and rotating directions called plunging and rotating modes, respectively. This results in oscillating forces with two different frequencies on the runner blades, bearings and other rotating parts of the turbine. This study investigates the effect of transient operations on the pressure fluctuations exerted on the runner and mechanism of the RVR formation/mitigation. Draft tube and runner blades of the Porjus U9 model, a Kaplan turbine, were equipped with pressure sensors for this purpose. The model was run in off-cam mode during different load variations. The results showed that the transients between the best efficiency point and the high load occurs in a smooth way. However, during transitions to the part load a RVR forms in the draft tube which induces high level of fluctuations with two frequencies on the runner; plunging and rotating mode. Formation of the RVR during the load rejections coincides with sudden pressure change on the runner while its mitigation occurs in a smooth way.

• Asian Journal of Innovation and Policy
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• v.4 no.2
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• pp.154-177
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• 2015

India faces a formidable challenge in ensuring security of access to modern energy carriers to majority of its population. The fossil-fuel dominated centralized energy system has proved to be ineffective in creating sustainable access to energy, which suggests need for a radical and innovative approach. We present such an approach. First, the need for innovations given the implications of lack of energy access on sustainable development is assessed. Next, possible innovations with respect to technologies, policies, institutions, markets, financial instruments and business models are discussed. Finally, an economic and financial feasibility of implementing such innovations are analyzed. The results indicate that such a proposal needs an investment of US$ 26.2 billion over a period of 20 years for a GHG mitigation potential of 213Tg $CO_{2e}$. The proposition is profitable for the enterprises with IRRs in the range of 39%-66%. The households will get lifeline access to electricity and gas for cooking at an affordable monthly cost of about US$ 5.7.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.7
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• pp.352-357
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• 2005

In competitive electricity markets, the System Operator (SO) coordinates the overall maintenance schedules when the collective maintenance schedule reported to 50 by Gencos not satisfy the specified operating criteria, such as system reliability or supply adequacy. This paper presented a method that divides generator maintenance scheduling of the 50 into a master-problem and a sub-problem. Master-problem is schedule coordination and sub-problem is DC-optimal power flow. If sub-problem is infeasible, we use the algorithm of modifying operating criteria of master-problem. And, the 50 should use the open information only, because the information such as cost function of a generator and bidding Price is highly crucial for the strategies of profit maximization.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.5
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• pp.287-293
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• 2003

The deregulation and structural reform of power markets have started from the early 90s, which has brought about new studies on the new environment. Regardless the market structure, however, power systems need to be operated and planned in a stable and reliable manner. Therefore, decisions on proper amount of operating reserves and their reliable operations are very important. Up to now, the decision processes of operating reserves depend mainly on experiences of operators in Korea. When Korean power market comes under private management, operating reserves would influence power rate as well as power Quality, Therefore, it is time to prepare reasonable operating reserve standards in a systematic way for the new environment. This study suggests the proper operating reserve standards considering rules of the power market in Korea. To verify the adequacy of the proposed standards, stability and frequency characteristics of the Korean power system are analyzed as well.

• Proceedings of the KIEE Conference
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• summer
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• pp.728-730
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• 2004

Transmission congestion is one of the Key factors to local market power in competitive electricity markets. Other players' strategy is also considered. This paper presents an alternative methodology in market power under transmission congestion and other players' strategy. The proposed methodology was demonstrated with the Optimal Power Flow(OPF). Case study is fulfilled by GAMS simulation.