• Proceedings of the KIEE Conference
• /
• 2005.07a
• /
• pp.462-464
• /
• 2005

This paper analyses the transient phenomena against single line to ground fault and lightning surge between Korea and Japan on underground power cable systems. For analysis, find proper earthing resistance of neutral grounding system adopted in Japan. This paper is expected to contribute the establishment of proper protection methods against transients on underground power cable systems.

• Proceedings of the KIEE Conference
• /
• 2002.11b
• /
• pp.319-322
• /
• 2002

Distance relay is operated in calculating line impedance. It can be worked accurately in overhead line. However, power cables or combined transmission lines need compensation for calculated impedance because cable systems have sheaths, grounding wires and sheath voltage limiters(SVLs) Neuro-fuzzy can be viewed either as a fuzay system, a neural network or fuzzy neural network and it can estimate the location of the fault accurately. In this paper, fault section and fault location can be classified and estimated in neuro- fuzzy inference system and neural network.

• Journal of the Korean Society of Safety
• /
• v.36 no.5
• /
• pp.10-17
• /
• 2021

The controversy over the risk of the human body being affected by electromagnetic fields emitted from 60 Hz power lines continues without end. There are currently no new studies or research progress being made in this direction that is notable, and the number of civil complaints is gradually increasing. The problem is that each study produces different results, among which the effect of exposure to magnetic fields on childhood leukemia is a major one. In Korea, an electrician who was maintaining a 22.9 kV power line died of leukemia, which has recently been recognized as an occupational disease. Methods to reduce magnetic fields from power lines include shielding with wire loops, incorporating split phases and compaction techniques, installing underground power lines, converting to high-voltage direct current (HVDC), and increasing the ground clearance of transmission towers. Depending on whether a separate power supply is needed or not, there are two types of wire loops: passive loop and active loop. Magnetic field reduction is currently done through underground power lines; however, the disadvantage of this process is high construction costs. Installing passive loops, with relatively low construction costs, leads to lower magnetic field reduction rates than installing underground cables and a weakness to not solving the landscape problem. This methodological study aims at designing methods and reducing the effects of 2-wire set loops-the simplest and most practical. Since the method proposed in this study has been designed after analyzing the distribution of complex electromagnetic fields near the expected loop installation location, a practical design can be implemented without the need for any difficult optimization programming.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2010.09a
• /
• pp.605-614
• /
• 2010

In this paper, the initial behavior of transmission tower was analyzed. This tower was firstly constructed by rock anchor foundation in domestic 154 kV transmission line and wireless real-time monitoring system was installed to obtain the measured data for analysis of the structure behavior. For this purpose, 16 strain gauges was installed in anchors of foundation and strain gauges, clinometers, anemoscope and settlement sensors was installed at superstructure. As the results, the main factor which influence the behavior of superstructure is wind velocity, wind direction, rainfall and temperature change. Especially, the uplift load at stub of transmission structure revealed about 35.4 percentages of design load. Hereafter the long term stability will be analyzed.

• Journal of Science and Technology Studies
• /
• v.19 no.3
• /
• pp.119-166
• /
• 2019

The risk of electromagnetic field(EMF) from power lines has been heavily disputed whenever high-voltage power line towers were built in South Korea. Local communities and civic groups had regarded burying the lines in the ground as an alternative to building power line towers. In 2014, however, when an elementary school science teacher reported the results of EMF measurements over the underground power lines to the Asian Citizens' Center for Environment and Health (ACCEH), the risk controversy over underground power lines took a whole new turn. The level of EMF from underground power lines turned out to be higher, and therefore more harmful than that from power line towers. In the debates that took place from then on over the EMF risk, ACCEH and NIER(National Institute of Environmental Research) presented conflicting topographies of EMF risk. This paper examines measuring practices of ACCEH and NIER by analyzing the measuring sites, measuring devices, and measuring heights chosen by each organization. This paper further examines how ACCEH and NIER mobilized various standards(EMF exposure limit, measurement guideline, categorization of carcinogens) differently. This controversy on the EMF from underground power lines of Seoul has raised concerns on the non-thermal effects of EMF in the long-term exposure and has led people to question whether burying the power lines is the safe alternative to building power line towers. Furthermore, this suggests conflicting answers on whether Seoul, where 90 % of transmission lines were already buried, is a safely managed place or not.

• Tunnel and Underground Space
• /
• v.8 no.3
• /
• pp.194-199
• /
• 1998

This research was aimed to figure out the trend of dust diffusion at open pit limestone mine for assessing the environmental impacts on the high voltage power transmission line. It is rather easy to assess the dust generation and size distribution of limestone dust at the blasting site, but it is very hard to assess the expected area of dust diffusion and amount of dust fall by the distances from the dust source. In this research, a 3-dimensional fluid dynamic simulation software (3D-Flow) was used for analysing the above mentioned matters to assess the impacts to the insulators on the transmission tower by the blasting dust. It was verfied that the 3D-Flow is reliable tool for simulating dust movement, and the limestone dust is not much hazardous to the power transmission line.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.57 no.10
• /
• pp.1720-1725
• /
• 2008

Because of the continuous increasing of energy consumption, metallic pipelines are widely used to supply services to customers such as gas, oil, water, etc. Most common metallic pipelines are underground and are now frequently being installed in nearby electric power lines. In recent years, buried gas pipeline close to power lines can be subjected to hazardous induction effects, especially during single line to ground faults. because it can cause corrosion and it poses a threat to the safety of workers responsible for maintenance. Accordingly, it is necessary to take into consideration for analysis of induced voltage on gas pipelines in transmission lines. This paper analyzed the induced voltage on the gas pipelines due to the 154kV transmission lines in normal case and in different faulty case conditions using EMTP (Electro-Magnetic Transients Program).

• Journal of Electrical Engineering and Technology
• /
• v.10 no.4
• /
• pp.1471-1479
• /
• 2015

A major portion of the capital costs in the present day power transmission systems are due to the cost of equipment and construction process. Transmission utilities in the recent years are drawing greater attention towards performing life cycle costing studies for cost management and decision making. However, the data involved in these studies are highly uncertain and the effect of these uncertainties cannot be directly included in the study process, resulting in inaccurate solutions. Interval mathematics provides a method for including these uncertainties throughout the cost analysis and provides final solution range in the form of intervals. In this regard, it is essential and extremely important that significant research has to be carried out in understanding the principles of life cycle costing methodology and its applicability to cost analysis of transmission lines along with uncertainties involved in the cost assessment process. In this paper, economic analysis of power transmission lines using interval mathematics has been studied. Life cycle costing studies are performed using net present value analysis on a range transmission lines used in India and the results are analyzed. A cost break even analysis considering right of way costs was carried out to determine the point of economy indifference.

• Proceedings of the KIEE Conference
• /
• 1988.11a
• /
• pp.224-228
• /
• 1988

Extensive development work which was carried out by Gold Star Cable Co., Ltd. has led to the optimal design, manufacture and test of fully engineered cable system for 345 kV self- contained oil filled (OF) underground cable. Details of design criteria and of tests are given. development of 345kV OF cable results in sucessful operations for ultra-high voltage power transmission requirement.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.1514-1515
• /
• 2007

본 논문에서는 송전선로 건설시 특히 대두되는 전자파에 대한 민원사례에 대해 다루고 있다. 특히 최근의 민원사례는 가공송전선로에만 국한된 것이 아니라, 비교적 환경친화적이라고 여겨지는 지중송전선로에 대해서도 발생하고 있는 바, 지중송전선로에 대한 실제 민원사례 및 전자파에 대한 예측결과를 수록하여 전자파 민원사례에 대한 참고자료로 활용하고자 한다.