• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.852-857
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• 2007

For electric traction using a large power converter, harmonic problem in the p-ower quality and regenerating energy in side of efficiency are important. Recently, by advance in power electronics technology, some countries are considering regenerative inverter from the points of view. when the electric tractions are stopped or driven through the falling slope way, it is very useful to supply surplus energy to the power source by regenerating system in the efficient side of energy and it is very economical. these regenerating energy are supported electrical equipment through DC line. In this research, the purposes are suppressing extra DC-line voltage and saving energy generated while electric traction is been driving on the falling slope way or reducing speed for railway using a 1500V DC-voltage. Besides, the accompanied defects of current distortion, low power factor and the voltage unbalance will be solved by developing the algorism of inverter having ability to compensate current harmonic.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.294-297
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• 2014

A Shipboard power system consists of three or four diesel generator sets connected to a grid. In case of dual fuel diesel generator sets employed LNG ship as a prime mover, large amounts of electricity are required for electric propulsion, auxiliary machinery and accommodation facilities. The electrical connection between generators through a network, torsional vibration can lead power swings. In this paper, the influence on the network by the torsional vibration of diesel generator sets in grid operation were studied. The torsional vibration characteristics were investigated and analyzed through theoretical analysis and the vibration measurement and the results were presented.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1626-1628
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• 1998

In reccent years the large capacity underground power transmission systems have been required gradually with the increasing demand of electric power, the increasing electric power system and the environmental limitations of an overhead transmission line in the city. But it is difficult to get the space for the underground power transmission lines because of complicated distributions of underground public facilities. But as the superconducting power cables have the large power transmission capacity, the high power transmission density, and low loss characteristics in comparison with a conventional cable, the necessity for their development are increasing. In this paper, the results of the conceptual design of HTS power cable is described.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.235-240
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• 2008

Since urban railway transit is one of the most essential transportation systems, its power facilities must ensure high reliability and safety. Currently, urban railway operating organizations perform TBM (Time Based Maintenance) on power facilities. However, in order to improve management efficiency and system safety, CBM (Condition Based Maintenance) is preferred. Among various power facilities, mold transformers has been chosen as the object of study since it is widely used for the purpose of minimizing volume and weight, and due to safety against fire. In this paper, various transformer failure cases due to electric, thermal, mechanical and environmental factors have been collected and analyzed. In addition, investigation on national and international condition based maintenance cases and the characteristics of sensors widely used for transformer monitoring has been performed to suggest the optimal condition based maintenance technique for urban railway systems.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 D
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• pp.2825-2827
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• 2000

In electric power industry. load balance has been one of the most fundamental and important management goals. Therefore. the strategy to achieve high quality load management now includes load balance besides the stabilization of electricity supply and quality management of electricity. Amongst many techniques of load management. direct load management has been actively studied and utilized to increase power facility and peak load suppression. Higher peak load situation is appeared during summer than during winter in Korea. and approximately 20% of the peak load is due to the load for air-conditioning. To cope with this peak load problem during summer KEPCO is performing a research project to develop a system to remotely control air-conditioning load using wireless communication. Currently, applicable facilities are limited to small-scale air-conditioning facility that has less than 2KW power capacity. This paper described the 1st year of efforts made in the study.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2006년도 춘계학술대회 논문집
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• pp.449-451
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• 2006

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전력기술부문
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• pp.27-29
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• 2001

As the amount of electric power consumption is increasing rapidly, the power systems are complex and growing larger. It is required that the quality of electricity is better. To satisfy this demands It is required to analyze the data of the fault accurately and then to find a cause and to enforce a countermeasure. We analyzed the fault of transmission & substation installation over 66kV statistically to operate the power system well. We introduced the faults that are classified into the cause, the facilities, the voltage. This paper explains the experience of the fault in electric power coporation that is operating the large power system. This paper will be meaningful. because this paper gives the data of real power system. We wish that the reliability of power suppliment will be improved, as using this paper properly and this paper is helpful to the growth of this field and the development of technology.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.856-857
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• 2007

For the sake of a stable power supply, an electric power company must have power generation facilities that can generate more electricity than the maximum demand of the year. Due to the fact that the maximum electricity demand will also continue to increase, enormous investments are needed annually to build power plants. For that reason, electric power companies are propelling 'Demand Side Management' which improve the form of electrical usage for the customer in a positive way. This paper presents the concept of 'Cool Storage System' which is the most representative program, which lowers the peak demand during the on-peak time periods in a day and creates a base load simultaneously during the night time hours among the DSM programs.

• 한국정보통신학회논문지
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• 제8권2호
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• pp.413-419
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• 2004

본 논문은 전기설비로부터 방전신호 검출을 통한 전기화재 예측 기법에 관하여 기술하였다. 방전현상으로부터 전기화재 예측에 필요한 전기적 정보를 얻기 위하여 절연지를 통한 연면 방전, 선간 단락 등 다양한 방전현상을 실험적으로 모의하였다. 실험결과로부터 전기화재 발생시 전원주파수와는 다른 특징적인 주파수 신호가 대부분 차지하는 것을 알 수 있었다. 최종적으로 실험결과에 근거한 방전신호 검출장치를 설계ㆍ제작하였으며, 전원선에서 방전신호를 모니터링하는 것으로 전기화재의 예측이 가능함을 확인하였다.

• Nuclear Engineering and Technology
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• 제52권5호
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• pp.956-963
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• 2020

Dose optimization for Radioactive Occupational Personal (ROP) is an important subject in nuclear and radiation safety field. The geometric environment of a nuclear facility is complex and the work area is radioactive, so traditional navigation model and radioactive data field cannot form an effective environment model for dose assessment and dose optimization. The environment model directly affects dose assessment and indirectly affects dose optimization, this is an urgent problem needed to be solved. Therefore, this paper focuses on an environment model used for Dose Assessment and Dose Optimization (DA&DO). We designed a multi-layer radiation field coupling modeling method, and then explored the influence of the environment model to DA&DO by virtual simulation. Then, a simulation test is done, the multi-layer radiation field coupling model for nuclear facilities is demonstrated to be effective for dose assessment and dose optimization through the experiments and analysis.