• The Journal of Korea Robotics Society
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• v.10 no.1
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• pp.9-15
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• 2015

We present a robust power transmission lines detection method based on vanishing point estimation. Vanishing point estimation can be helpful to detect power transmission lines because parallel lines converge on the vanishing point in a projected 2D image. However, it is not easy to estimate the vanishing point correctly in an image with complex background. Thus, we first propose a vanishing point estimation method on power transmission lines by using a probabilistic voting procedure based on intersection points of line segments. In images obtained by our system, power transmission lines are located in a fan-shaped area centered on this estimated vanishing point, and therefore we select the line segments that converge to the estimated vanishing point as candidate line segments for power transmission lines only in this fan-shaped area. Finally, we detect the power transmission lines from these candidate line segments. Experimental results show that the proposed method is robust to noise and efficient to detect power transmission lines.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.1103-1105
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• 1998

It is becoming more and more difficult to construct new transmission lines because of many social problems. According to the load increase, Some of existing transmission lines will be heavy loaded over the limit. To solve this situation, one of method is peformed by replacing existing ACSR transmission lines with STACIR for increasing power transmission capacity in the 345kv transmission system. This paper presents several techniques for design and construction of transmission line replacement based on the actual experience in the 345kv Shinseongnam-Shinsiheung and Shinseongnam-Shinyeongseo transmission lines.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.7
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• pp.1221-1225
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• 2010

The application of the AC and DC lines on the same transmission tower is an economical and practical approaching that increase the power transmission capacity of an existing transmission corridor. But, In this case, Inductive and capacitive coupling between AC and DC lines on the same tower should be investigated in advance. According to the installation plan of 80kV ${\pm}$60MW bipole HVDC in Cheju, KOREA that will be commissioned until 2011, DC lines will parallely operate with 154kV 2 AC lines in existed 154kV AC 4 lines transmission tower. This paper presents the steady state analysis results about the interaction between 154kV AC and 80kV DC lines in the same transmission tower.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.1
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• pp.14-19
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• 2011

The implemetation of the AC and DC lines on the same transmission tower is an economical and practical approaching that increase the power transmission capacity of an existing transmission corridor. But, In this case, Inductive and capacitive coupling between AC and DC lines on the same tower should be investigated in advance. According to the installation plan of ${\pm}80kV$ 60MW bipole HVDC in Jeju island, KOREA that will be commissioned until 2011, DC lines will parallely operate with 154kV 2 AC lines in existed 154kV AC 4 lines transmission tower. This paper presents the transient analysis results about the interaction between 154kV AC and 80kV DC lines in the same transmission tower.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.416-418
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• 2000

Main power transmission network in Korea is consist of 154kV, 345kV transmission lines. Also 765kV transmission lines are on construction currently. There are some differences in the insulation design concept, methods and contents on 154kV, 345kV and 765kV overhead transmission lines respectively. In this paper, we described and summarized the applied insulation design concept, methods and features on each transmission lines.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.10
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• pp.123-129
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• 2010

During the past 2 decades, many electric power companies have been searching various solutions in order to supply power with economical and more efficiency in the present transmission utilities. Most interesting method to increase the line capacity of overhead transmission lines without constructing any new line might be to adapt Dynamic Line Rating(DLR). Specified rating is normally determined by any current level, not by conductor temperature. Although specified rating is essential to design transmission line, dip may be the most important factor in limiting transmission capacity. Transmission lines built by the oldest dip criterion among the 3 different design criteria for conductor dip are nearly over one-half of all Kepco's transmission lines. This paper describes an up-rating method for those transmission lines in order to apply DLR technique. Based on limit dip conductor temperature and current of the transmission lines, limitation performance and effectiveness in applying DLR with weather model are analyzed. As a result of analysis, it can be shown that an improved method could be effectively used for increasing the line rating of old transmission line which was built by the design criterion with low dip margin.

• Journal of the Korea Convergence Society
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• v.4 no.4
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• pp.49-57
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• 2013

The lightning shielding of different 500 kV HVAC-TL high voltage AC transmission lines was analyzed. The studied transmission lines were horizontal flat single circuit and double circuit transmission lines. The lightning attractive areas were drawn around power conductors and shielding wires. To draw the attractive areas of the high voltage transmission lines, transmission line power conductors, shielding wires and lightning leader were modeled. Different parameters were considered such as lightningslope, ground slope and wind on lightning attractive areas. From the calculated results, the power conductors voltages affected on attractive areas around power conductors and shielding wires. For negative lightning leader, the attractive area around the transmission line power conductor increased around power conductors stressed by positives voltage and decreased around power conductors stressed by negative voltage. In spite of this, the attractivearea of the transmission line shielding wire increasedaround the shielding wire above the power conductor stressed by the positive voltage and decreased around the shielding wire above the power conductor stressed by negative voltage. The attractive areas around power conductors and shielding wires were affected by the surrounding conditions, such as lightning leader slope, ground slope. The AC voltage of the transmission lines made the shielding areas changing with time.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.107-108
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• 2007

Overhead transmission lines are completely exposed to the environment. This causes faults in transmission lines due to natural environmental conditions. In some cases, transmission towers are damaged by typhoons and snow, as well as sleet on the transmission lines. It takes a lot of time to repair the damaged towers. For emergency restoration purposes, steel poles are installed to temporarily supply power. Before 2003, emergency restoration steel poles were made of angled steel, which required a large number of beams, bolts, etc. In addition, the foundation of the steel pole and ground wire was constructed using excavation and burial methods, therefore it required a lot of manpower and time to construct temporary transmission lines. In September 2003, typhoon Maemi, whose maximum wind speed was 60m/s, hit Korea. 'Maemi' destroyed transmission lines in the Busan and Geojea area, causing long blackouts. To reduce the recovery time to the damaged transmission lines, self-build based emergency towers were developed. self-build based emergency towers reduced recovery time from 24 hours to 4 hours or less. However, the self-build based emergency tower had no arms, so the temporary transmission lines could only be constructed without curves in line routes. In this paper, solving these self-build based emergency tower limitations, using insulated arms(designed for use with the self-build based emergency tower), shall be explained.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.2
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• pp.63-70
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• 2019

Electric transmission towers are facilities to transport electrical power from a plant to an electrical substation. The towers are connected using wires considering the wire tension and the clearance from the ground or nearby objects. The wires are installed on a rights-of-way that is a strip of land used by electrical utilities to maintain the transmission line facilities. Trees and plants around transmission lines must be managed to keep the operation of these lines safe and reliable. This study proposed the use of a low-cost drone photogrammetry for the transmission line rights-of-way mapping. Aerial photogrammetry is carried out to generate a dense point cloud around the transmission lines from which a DSM (Digital Surface Model) and DTM (Digital Terrain Model) are created. The lines and nearby objects are separated using nDSM (normalized Digital Surface Model) and the noises are suppressed in the multiple image space for the geospatial analysis. The experimental result with drone images over two spans of transmission lines on a mountain area showed that the proposed method successfully generate the rights-of-way map with hazard nearby objects.

• Journal of Electrical Engineering and Technology
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• v.6 no.6
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• pp.742-749
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• 2011

Power transmission lines are one of the most important components of electric power system. Failures in the operation of power transmission lines can result in serious power system problems. Hence, fault diagnosis (transient or permanent) in power transmission lines is very important to ensure the reliable operation of the power system. A hidden Markov model (HMM), a powerful pattern recognizer, classifies events in a probabilistic manner based on fault signal waveform and characteristics. This paper presents application of HMM to classify faults in overhead power transmission lines. The algorithm uses voltage samples of one-fourth cycle from the inception of the fault. The simulation performed in EMTPWorks and MATLAB environments validates the fast response of the classifier, which provides fast and accurate protection scheme for power transmission lines.