• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.481-482
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• 2008

This investigation presents a method to design an optimal shape of a matching waveguide connecting two waveguides having different impedances. The design objective is to maximize power transmission through the waveguide system. When an incident wave impinges on an elastic waveguide system consisting of waveguides of different impedances, all of the incident wave power may not pass through due to the mechanical impedance. Therefore, the maximization of the transmitted power through a waveguide difficult to achieve without a systematic design method. In this work, the optimal shape design of a matching waveguide connecting two waveguides of different impedances is formulated as a shape optimization problem. If the material of the matching waveguide is given, its shape is the only parameter controlling the transmission power. Relatively simple one dimensional elastic wave transmission problems will be considered in this work, but the underlying methodology and the related physics can be clearly demonstrated. The influences of initial configurations as well as the target frequencies on the optimized shapes will be also investigated.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.429-434
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• 2009

In this paper it was written about the safety management plan for underground power transmission cable, and it guarantees the reliable electric power supply and facility management to prevent an electric disasters according to that. Recently fires which happens on OF Cable lead to a breakdown of power system and cause a power outage of wide area and serious social problems. So it needs an improvement of inspection ability on OF cable as well as a strict inspection system to prevent that problems in advance and it will bring us the development of electric safety management and the reliable electric power supply.

• Journal of Power Electronics
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• v.19 no.2
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• pp.602-611
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• 2019

The major drawbacks of magnetic resonant coupled wireless power transfer (WPT) to the embedded sensors on spindles are transmission instability and low efficiency of the transmission. This paper proposes a novel double-loop coil design for wirelessly charging embedded sensors. Theoretical and finite-element analyses show that the proposed coil has good transmission performance. In addition, the power transmission capability of the double-loop coil can be improved by reducing the radius difference and width difference of the transmitter and receiver. It has been demonstrated by analysis and practical experiments that a magnetic resonant coupled WPT system using the double-loop coil can provide a stable and efficient power transmission to embedded sensors.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.38-39
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• 2008

KEPCO conducted the project called the "Feasibility Study for the Han (Ghana) - Bobo Dioulasso (Burkina Faso) - Bamako (Mali) Interconnection Project" as its first African project. This paper deals with power system analysis and Transmission line and substation design of approximately 750 kilometers of the 225 kV single circuit transmission lines and six substations. The main contents of the power system analysis results and preliminary engineering design include power flow, transient stability, eigenvalue analysis, transmission line design, substation design and economic analysis.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.880-883
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• 1998

In this paper, sensitivity based approach to estimate BITC(bilateral interchange transfer capacity) considering the real power flow control function of FACTS device is presented. The real power flow setting of the FACTS device is adjusted so that it transfer the power flow from the first violation point of transmission capacity to other transmission lines in the power system, thus allowing more power to be transferred from the specified generator bus to the specified load bus. The transfer between the two bus locations is increased from this new operating condition until a violation of transmission capacity limits occurs or until the setting of the FACTS device can no longer be adjusted. The proposed algorithm is illustrated using examples of small and real life power system.

• KEPCO Journal on Electric Power and Energy
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• v.7 no.1
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• pp.73-77
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• 2021

As the big data analysis technologies has been developed worldwide, the importance of asset management for electric power facilities based data analysis is increasing. It is essential to secure quality of data that will determine the performance of the RISK evaluation algorithm for asset management. To improve reliability of asset management, asset data must be preprocessed. In particular, the process of cleaning dirty data is required, and it is also urgent to develop an algorithm to reduce time and improve accuracy for data treatment. In this paper, the result of the development of an automatic cleaning algorithm specialized in overhead transmission asset data is presented. A data cleaning algorithm was developed to enable data clean by analyzing quality and overall pattern of raw data.

• Proceedings of the KIEE Conference
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• 2008.11a
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• pp.107-109
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• 2008

Cheju-Haenam HVDC transmission system start it's commercial operation since 1998. JEJU island is supplied with it's about 45% of total electric power from main land with HVDC link. In JEJU island, the demand of electric power is growing every year. With a current power supply, electric power reserve rate will be below the recommended one. For a stable power supply to JEJU island, KEPCO start a construction of #2 HVDC transmission system. This report is for introduction and understanding of #2 HVDC system which will be installed between JEJU island and main land. This report includes a specification of converter station and DC cable. KEPCO expect that this system will solve the power supply problem and maximum wind power plant capacity problem as well.

• Proceedings of the KIEE Conference
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• 1996.11a
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• pp.112-116
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• 1996

This paper presents the study results of FACTS application plan for transmission capability Enhancement. Power transfer across the KEPCO system resulting from a concentration of load in the Kyung-In area are subject to thermal, voltage and stability constrains. In the analysis study of the KEPCO system in 2000 and 2006 year. voltage stability analysis. modal analysis and dynamic stability were simulated by the power system analysis tools(VSTAB, PSS/E).

• Proceedings of the KIPE Conference
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• 1997.07a
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• pp.211-215
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• 1997

Localized communication networks for office automation, security monitoring, environmental management of buildings, computer communications, and other applications enjoy every increasing demand. This paper proposes a direct sequence spread spectrum communication system for use in power line data transmission. Advantages of power distribution circuits include reasonably universal coverage and easy access vis a standard wall plug. Disadvantages include limited communication bandwidth, relatively high noise levels, and varying levels of impedance, noise, and attenuation. Spread spectrum signalling provides immunity to narrow-band signal impairments and multiplexing capability. Our prototype power line communication module supports completely physical and data link layers based on the international standard ISO 10368 for reliable high-speed power line communication system. Moreover it provides useful functions to compose a plant monitoring and control system. All the circuits of the communication module are included in one compact circuit. Thus a functional communication system for the power line plant monitoring and control is implemented.

• Journal of Power System Engineering
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• v.17 no.5
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• pp.128-137
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• 2013

Modern transmission technologies such as automated manual transmission(AMT) and dual clutch transmission(DCT) are interested to all manufactures due to their fuel efficiency and driver's convenience, especially in a hybrid system. AMT has advantages in that they have a high efficiency of manual transmissions(MT) and offer operation convenience similar to automatic transmissions(AT), but it has some disadvantages in that they have torque gap during gear shift and shift time. To reduce disadvantages, it is necessary to evaluate errors and characteristics as a developing simulation model before experimental verification. The purpose of this study is to develop virtual components and simulate the transient response of AMT. A dynamic AMT model and a control logic for an integrated vehicle model have been developed using Matlab/Simulink as a simulation platform. In this paper, the clutch model to describe the stick-slip transition mode and the transmission model to describe the neutral gear shifting is introduced and compared with each other.