• Journal of the Korean Society for Railway
• /
• v.9 no.3 s.34
• /
• pp.319-324
• /
• 2006

Studied was a strategy of technology development for railway system in terms of railway network. First, The successful launch of the Korean HST system has not only decreased logistics burden but also significantly transformed the Korean trunk-line railway network, revolutionizing the logistics and technology sectors and reinvigorating the Korean railway industry in one century. Korean railway industry sector is now investing to develop many different types of railway system(G7, Post G7, tilting train...) so that these kinds of various railway system development should be integrated with the National Inter-modal Transportation Network Plan. To secure sufficient capacity that is required by the National Railroad Plan, the railway industry needs to establish mid- and long-term train purchase and operation strategies in compliance with railway construction and operation policies. During a railway construction planning, train operators, based on their train operation strategies, should come up with measures to closely cooperate with project operators from the planning stage through to the opening of a railway system. To be more precise, train operators should establish long-term train procurement plans reflecting both long-term national railroad network plans and plans for each railway line in order to suggest appropriate roles and schedules for each line. Also, based on the long-term railway plan, directions should be decided concerning the research and development of trains in advance.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.51 no.6
• /
• pp.290-295
• /
• 2002

The present assignment in installing the number of switches for distribution line was made on the basis of a normal feeder capacity 7,000kVA in KEPCO(Korea Electric Power Corporation), Korea. But the normal capacity is revised to 10000kVA in 1998. Even increasing limit of the operating capacity of the distribution lines enables us to give some benefit for the operation flexibility and investment cost of the distribution system. It is disadvantageous in the viewpoint of supply reliability. In distribution systems, switches are equipped to improve the reliability of distribution systems by minimizing the outage section due to fault and maintenance. Utility generally improves the reliability by minimizing the length of outage section, which is caused by fault and maintenance, through switch equipment on distribution system. In order to cope with the changes such as operation capacity, it is necessary to study whether the present criteria is reasonable or not, also to confirm whether the present criteria of installing switches in line is improved or not. In this study, we proposes the number of switch per feeder on the basis of present operation capacity in distribution system.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.1059-1065
• /
• 2011

In line with the expansion of electric railway, reducing carbon emission and optimal train operation are required by economical, eco-friendly and efficient management. Most of the energy consumption in electric railway is consumed by train operation. So it is important that minimize the energy consumption in train operation. An analysis of the operation performance of the new model vehicle which in South Korea, Korail introduced shows that the energy consumption is different in line with the skill level of the engine driver. In this study, the know-how of train operation of a skilled engine driver is systematized by using artificial intelligence, and the technique which supports engine drivers with train operation was offered. As a result of applying in South Korea, the Gyeongbu line by using simulation, it confirmed that the maximum 20% can reduce the energy consumption in comparison with unskilled engine drivers in case of applying the Expert System.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.4
• /
• pp.2324-2329
• /
• 2014

The inspection of distance to go train control system conducted only when train is in main line or inspecting line, that affects low work efficiency and hazard elements to safe operation. Before or after train operation, the interface test between on-board and wayside signal system must be conducted. In this paper, onboard signal interface inspection system based on the real-time automatic analysis of onboard system status information that is transmitted to the wayside system and the operation status check of the onboard signal device operates as a virtual train information that is transmitted to the onboard system have been proposed. And after building the inspection system to the inspecting track of Daejeon Subway Line 1, Panam Depot, the verification algorithm of proposed interface test and the results was presented. therefore, it has enhanced work efficiency to do not carry train operation of a half hour in test line to test on-board system.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.8 no.6
• /
• pp.585-592
• /
• 2003

The parallel operation system of UPS is used to increase reliability of power source at critical load. But parallel UPS system has a few defects, impedance is different from each other and circulating current occurs between UPSs, due to line impedance and parameter variation, though controlled by the same synchronization signal. According to such characteristic of parallel UPS, balanced load-sharing control is the most important technique in parallel UPS operation. In this paper, a novel power deviation compensation algorithm is proposed. it is composed of voltage controller to compensate power deviation that be calculated by using active and reactive current deviation between Inverters on synchronous d-q reference frame.

• Proceedings of the KSR Conference
• /
• 2001.05a
• /
• pp.80-87
• /
• 2001

The purposes of this primary study are the selection of rail station and train operation management techniques for express-rail operation service at the convectional railway electrification. For these analyses, we used the KNR statistics and KROIS data of rail stations and train users by rail line. Therefore, we chose the important stations for express-rail operation of Kyongbu conventional rail line (esp. Seoul-Jochiwon section) through the rail transportation demand. and then, suggested primary operational management plan thorough the effects analyses of decreasing total travel time and increasing transportation demand by train speed-up. This study has some bounds and limits for proceeding, as it does, we excluded as followings: the conditionals of fate system, headways and train diagram, economic/financial analysis and technological assessment, and other railway technological infrastructures and a certain railcar specification, etc. . We propose to enlarge this study into a feasibility study of express or skip-stop operation service and compatible vehicle system decision considering with the best possible investment rail line, furthermore. in front of Kyongbu (Seoul-Busan) high-speed rail open in 2004, we have to try to progress the efficiencies of railway operation applying various train operation management plan.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.52 no.12
• /
• pp.641-648
• /
• 2003

This paper proposes a novel UPFE based on H-bridge modules, isolated through single-phase multi-winding transformers. The dynamic performance of proposed system was analyzed by simulation with EMTDC, assuming that the UPFC is connected with the 138-kV transmission line of one-machine-infinite-bus power system. The proposed system can be directly connected to the transmission line without series injection transformers. It has flexibility in expanding the operation voltage by increasing the number of H-bridge modules.

• Proceedings of the KIEE Conference
• /
• 1996.11a
• /
• pp.175-178
• /
• 1996

Power system is becomming more and more complex and large. So system is stressed increasingly. This paper presents a method to select contingency ranking in power systems for EMS operation. Firstly, the proposed method is applied line outage using Thevenin equivalent circuit. Secondly, Contingency harmful to system is selected by loss variation between base case and fault. Thirdly, this paper prescribed simulated line sequence. Therefore this algorithm shows higher computation speed and effective memory use.

• Journal of the Korea Safety Management & Science
• /
• v.12 no.2
• /
• pp.65-73
• /
• 2010

In an automated industry PLC plays a central role to control the manufacturing system. Therefore, fault free operation of PLC controlled manufacturing system is essential in order to maximize a firm's productivity. On the contrary, distributed nature of manufacturing system and growing complexity of the PLC programs presented a challenging task of designing a rapid fault finding system for an uninterrupted process operation. Hence, designing an intelligent monitoring, and diagnosis system is needed for smooth functioning of the operation process. In this paper, we propose a method to continuously acquire a stream of PLC signal data from the normal operational PLC-based manufacturing system and to generate diagnosis model from the observed PLC signal data. Consequently, the generated diagnosis model is used for distinguish the possible abnormalities of manufacturing system. To verify the proposed method, we provided a suitable case study of an assembly line.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.59 no.12
• /
• pp.2135-2142
• /
• 2010

This paper studies the validity about a joint operation of neutral wire and overhead grounding wire in combined distribution systems. The overhead grounding wire and neutral wire are currently installed separately and grounded by common. However there is no any ineffectiveness or electrical problem in case of the proposed system, such system can be operated at real distribution system. Therefore this paper describes the suitability of a joint operation through lightning surge analysis on combined distribution systems. Lightning surge analysis is carried out by EMTP/ATPDraw to obtain the overvoltage of overhead line and underground cable in various conditions such as locations and current types of lightning stroke. Overvoltage gained by the analysis show that the insulation strength of the joint operation case is not stable compare with the current operation case.