• Journal of Electrical Engineering and Technology
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• v.7 no.1
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• pp.23-33
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• 2012

The current paper deals with a new live-line insulator inspection tool system that will be used by the Korea Electric Power Corporation for its 154 kV power transmission lines in 2011. Unlike the existing contact type tools, the developed inspection tool automates parts of the insulator inspection process using a sensor and an actuator. The tool sustains its weight independently, not by a lineman. In addition, the inspection tool measures the insulation resistance of an insulator together with its distribution voltage, thus providing more information for analysis and diagnosis. Such characteristics improve the system's operation efficiency, measurement reliability, and usability. We confirmed its effectiveness through live-line field tests with actual power transmission lines.

• Journal of Electrical Engineering and Technology
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• v.8 no.2
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• pp.359-363
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• 2013

The 765kV transmission line will be maintained by live-line works for efficient operation. In order to maintain the 765kV transmission lines safely by live-line works, lineman has to know switching impulse flashover characteristics of the jumper V-strings with damaged insulators in advance. In order to know the flashover characteristics this paper carried out experimental flashover mockup tests for jumper V-string with damaged insulators in the outdoors. And it suggests flashover characteristics of the 765kV jumper V-strings also. The results will be used in estimating the safety of live working for 765kV transmission lines.

• Proceedings of the KIEE Conference
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• 2005.07e
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• pp.127-129
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• 2005

OPGW(Optical Ground Wire) whose demand is increasing worldwide have composite function as optical communication and grounding for preventing transmission line from lightning. While continuous efforts have been made to increase the transmission capacity and speed, the working method to replace the existing ground wire with OPGW under live-line condition is coming to force newly as installation aspects. Particularly, this requirement became more serious in developing country that the electric power supply is not sufficient and power outage is impossible for supply and dead of electric power LS cable Ltd. has developed the new installation method in full live-line condition to solve the confronted problem and to meet the market demand. In this paper, Electric Problems in live-line installation is considered to predict dry-band arcing. This can be used by Makers to predict dry-band arcing in insulating ropes installed on earth wire of power transmission system.

• Fisheries and Aquatic Sciences
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• v.24 no.11
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• pp.383-389
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• 2021

On the southern coast of South Korea, dark-banded rockfish, sea bass, and red seabream are caught by single-line fishing. In particular, red seabream and sea bass are caught in the Jeollanam-do region using gear with attached fishing hooks, such as longline and single-line gear, with live shrimp as bait. The objective of this study was to compare the catch efficiency of two types of live shrimp (naturally grown Shiba shrimp [Metapenaeus joyneri] and cultured whiteleg shrimp [Litopenaeus vannamei]) used as bait. The investigation included interviews, on-board surveys, and water tank experiments. Interviews were conducted with relevant parties to determine the preference for live shrimp as bait, and the results showed a greater preference for cultured whiteleg shrimp. Further, an on-board survey was conducted to compare catch efficiency between these two types of live shrimp bait for single-line fishing. The on-board investigations were conducted once or twice a month between June and October. In total, the amounts of fish caught using naturally grown Shiba shrimp and cultured whiteleg shrimp were 56 and 52, respectively. Of these, the numbers of sea bass, the primary target fish species, caught using naturally grown Shiba shrimp and cultured whiteleg shrimp were 43 and 40, respectively. Thus, the results showed that there was almost no difference in the number of fish caught based on the bait used. However, according to a water tank experiment, cultured whiteleg shrimp survived longer than naturally grown Shiba shrimp.

• Journal of the Korean Society of Safety
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• v.33 no.2
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• pp.14-20
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• 2018

In this study, we analyze the current status of major disasters in distribution works and propose safety measures through the distribution live-line work method and electric shock risk assessment. The result of analyzing the ratio of electric shocks to the occurrence of industrial accidents in the recent 13 years shows that the death rate is higher than other industries, especially the construction industry occupying most of the disaster, and it is higher than the collapse disaster. We analyze statistic data of 101 victims selected as core words of live work, distribution line, pole and 22.9 kV in the investigation report of major accident of electric shock fatal from 2001 to 2014. The safety measure was established through the risk assessment of the distribution method using the standard model of the risk assessment based on the results of electric shock analysis on the distribution line. In order to prevent the electric shock accident which is recently being discussed, the risk assessment procedure were carried out in the above-mentioned 22.9kV special high voltage live-line operation method. We derived the risk reduction plan for the distribution line from the results of the major accidents statistic and demonstration of the line works.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.453-454
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• 2008

• Proceedings of the KIEE Conference
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• 2005.05b
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• pp.31-34
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• 2005

The 765kV transmission line will be maintained by live-line works for efficient operation, In order to maintain the 765kV transmission lines safely by live-line works, lineman have to know flashover characteristics of the insulator strings with damaged insulators. This paper suggests flashover characteristics of the 765kV insulator strings from experimental test results directly.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.6
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• pp.1239-1244
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• 2011

In our previous paper, we developed an insulator inspection robot system for a suspension insulator string in the 345kV power transmission line. However, this robot cannot be applied to a tension insulator string, because its constituent insulators are different in diameter and height from those of a suspension insulator string. To solve this problem, we developed a new live-line insulator inspection robot system that is applicable to both suspension and tension insulator strings. We confirmed its effectiveness through live-line performance tests.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.10
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• pp.672-676
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• 2017

Electrical energy is playing an increasingly vital role as the primary energy source in everyday life. With the increase in electric power consumption, power facilities are under an increasing stress and must operate at a high capacity. Consequently, the demand for electric power cables in power transmission and distribution lines is rapidly increasing. Underground distribution lines have been steadily replacing the aboveground lines owing to the increase in electric power demand and the need to increase the supply voltage. In addition to line damage, worker safety is of primary concern in this type of underground infrastructure. In this study, to improve the safety of workers dealing with underground transmission lines, we analyzed the electromagnetic field generated around the distribution line and determined the basic criteria for developing a device that can detect a live underground line.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.1
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• pp.89-95
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• 2010

A new live-line insulator tester was developed to detect faulty insulators in 154kV power transmission lines. This paper is the second part of the two-part paper and deals with its inspection algorithm development. Unlike normal condition with low pollution and low humidity, the inspection data measured in the field under high pollution or high humidity showed that the voltage distribution of an insulator string has offsets in comparison with those of others and its insulation resistances are greatly decreased, which leads to wrong results of the existing inspection algorithms under such conditions. To solve this problem, we propose new diagnosis algorithms that can exactly detect faulty insulators from measured data regardless of environmental conditions. Its effectiveness was validated by live-line field tests in actual power lines.