• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.500-502
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• 2003

This paper reviews calculating of induced voltage onto a communication line from 22.9kV-Y Distribution Lines. The coexistence of both power line and communication line in parallel generates the induction of significant longitudinal voltage in the weak current line. In order to evaluate a precise induced voltage, this paper indicated some problems about coefficient and numerical formula. It also presents some induced voltage production technology standard application.

• The Pure and Applied Mathematics
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• v.20 no.2
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• pp.109-116
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• 2013

In this paper, we propose a Jonckheere type test statistic for testing the parallelism of k regression lines against ordered alternatives. The order restriction problems could arise in various settings such as location, scale, and regression problems. But most of theory about the statistical inferences under order restrictions has been developed to deal with location parameters. The proposed test is an application of Jonckheere's procedure to regression problem. Asymptotic normality and asymptotic distribution-free properties of the test statistic are obtained under some regularity conditions.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.3
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• pp.417-422
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• 2022

It is always desirable that the continuation of power flow through the lines should not be interrupted for a long time. The optimized guideline of reclosers on distribution lines is known to improve the reliability of power systems, the protection functions on distribution systems heavily rely on the number and placement of such reclosers. This study reviewed the effect of using protection settings methodology with the number of reclosing operations to reduce the damage sustained during faults on distribution networks. The aim of the study is to determine the number of reclosing operations and fault current conditions based on simulation data of PSCAD/EMTDC for standard distribution networks. It is found that the determination of the number of operations on reclosers, which are the protection function of feeders, helped to optimize the operation and reliability of distribution networks.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.452-454
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• 2000

While magpies are making their nest and are laying eggs from February to May time frame, the electrical power incidents by magpies are as high as 30% of all. This research will examine the establishment of frequency of magpies by utilizing Alarm Calls with their own voice characteristic and also try avoiding access to distribution equipments in order to prevent from constructing their nests on the distribution lines. This research results contribute to improve the reliability in the power distribution line.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.1321-1324
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• 2004

Unbalanced systems, such as distribution systems, have difficulties in fault locations due to single-phase laterals and loads. In this paper, a novel fault location algorithm is suggested for a line to line faults using inverse theorem of matrix on electric power lines. The fault location for balanced systems has been studied using the current distribution factor, by a conventional symmetrical transformation, but that for unbalanced systems has not been investigated due to their high complexity The proposed algorithms overcome the limit of the conventional algorithm using the conventional symmetrical transformation, which requires the balanced system and are applicable to any electric power system but are particularly useful for unbalanced distribution systems. The simulation results oriented by the real distribution system are presented to show its effectiveness and accuracy.

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1456-1458
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• 1999

As the system reliability of power supply is highly increased, we need distribution maintenance techniques without any power interruption. To meet such an increasing demand, a groat deal of hot line work on the high voltage overhead distribution lines has been carried out. In this regard, Hot line work techniques has being applied widely. However, hot line work techniques can not cover all kinds of work without interruption. To cope with those problems, the temporary power supply work technique such as bypass cable truck technique, temporary switch technique and mobile transformer technique was developed and applied. This paper presents the most optimal method according to distribution work contents through the comparison and analysis the characteristis and problems of the existing various work techniques. Also this paper suggested the countermeasers of the prsent problems.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.5
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• pp.773-782
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• 2008

This paper describes the method for proper location of protective equipment in underground distribution cable through field test and analysis at testing lines. To prove the reliability for analysis simulated by EMTP/ATPDraw, the testing results obtained by the real test and the analysis for the same test lines were compared each other. The accuracy of analysis was proved by the comparison. Over voltages were measured and analyzed at each point of cable and switches in case of which lightning surge current was applied. The analysing method was applied to real distribution systems to select the proper location of protective equipment. It is evaluated that the location of protective equipment was properly selected.

• Journal of Distribution Science
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• v.13 no.10
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• pp.15-21
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• 2015

Purpose - This study examines a bundling effect on production and distribution in a patent-protected industry. Despite the heavy use of bundling strategies in the information and technology industry, literature has paid scant attention to bundling of intellectual property rights. This study examines a theoretical exploration of the bundling effect on licensing behavior. Research design, data, and methodology - To address this behavior, we build a simplified model consisting of three stages: 1) bundling decision, 2) licensing agreement, and 3) competition. The subgame perfect Nash equilibrium is applied to the model. Results - A single-patent holder with superior technology grants its own license to the multiple-patent firm, thereby leaving the market. Anticipating the single right holder's licensing strategy, the multiple-patent firm offers a bundle, making the single-right holder's bargaining position weaker. Conclusions - Bundling is an effective business strategy, resulting in multiple products for a firm as it faces other firms with single-product lines in each market. Taking advantage of the multi-patent or multi-product lines, the firm utilizes the bundling strategy obtaining better technology from the standalone single-patent firms.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.689-691
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• 1996

Our country, is still suffering from much work outage, nearly 80% of total outage time, in 22.9kV-Y multi-grounded distribution lines. Therefore, KEPCO which is the sole utility owned by the Korean government ms developed outage-free work techniques to improve the reliability of power supply in Our country. This paper is to introduce the developing process and good effects of outage-free work techniques, and the equipment developed and applied in Our country. This paper will aid many utilities to try to reduce the work outage.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.10
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• pp.1383-1389
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• 2013

There were telecommunication noise and malfunctions of the electronic devices occurred over a wide area due to the high harmonic voltage and/or current levels of the Back-to-back converter in the DFIG wind power system even though the magnitude of all harmonics is within the international standards. The triangular carrier signals of the PWM used in the power converter system is related to the telecommunication noise because they are in the range of audible frequencies and amplified by a variety of the standing waves that were excited by harmonic voltage sources in the weak grid system such as a long distance distribution transmission lines. This paper describes the characteristics of the harmonics in the wind turbine-generator, numerical analysis and simulation of the harmonics resonance phenomena in the distribution lines as well as measuring induced voltage of the telecommunication lines in parallel with power lines in order to verify the root cause of the telecommunication noise. These noise problems can occur in a wind turbine power system with a non-linear converter at any time, as well as photovoltaic power system. So, the preliminary review of suitable filter devices and switching frequencies of the PWM have to be required by considering the stability of the controller at the design stage but as part of the measures the effect of the telecommunication cable shields was analyzed by comparing the measured data between multi-conductor with/without shields so as to attenuate the sources of the harmonics voltage induced into the telecommunication lines and to apply the most cost-effective measures in the field.