• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1963-1965
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• 2000

This paper deals with a problem of detecting the inner corrosion of the ACSR(Aluminum Conductor Steel Reinforced) power lines using a detector which consists of an ECT(Eddy Current Test) sensor, a constant current service, a signal processing unit, and a RF transmitter/receiver unit. The detector runs on the ACSR transmission line and inspects the corrosion of the conductor using the technic of the nondestructive eddy current test. The experimental result shows this detector can efficiently find the zinc loss in ACSR power lines.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.109-112
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• 2003

Small impedances in the superconducting parallel circuits cause unequal distribution of the currents in the circuits. This results in quenches or losses in some superconducting parts and decrease of total transport current. This paper presents the fabrication and test results of a superconducting multi- interphase transformers (SIPT) for equal current distribution in superconducting parallel circuits. The secondary loop configuration with air core SIPT seems to be the most efficient one for the SFCL. Test results show that the SIPT can effectively make the current distribution uniform in Parallel circuits that have unequal resistances.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.4
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• pp.307-311
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• 2016

Several types of supercapacitors have been developed for energy storage systems. Among them, the hybrid type has advantages such as a large capacitance per weight compared with the electric double-layer capacitator type. In this study, constant current charging and discharging tests were conducted for recently developed hybrid-type supercapacitors. Based on the experimental results, the capacitance and equivalent series resistance were obtained. The capacitance was larger than the designed capacitance at a low current but became small at a high current. In addition, the capacitance depended on the cell voltage. These results can be used to design an energy storage system.

• Proceedings of the KIEE Conference
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• summer
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• pp.839-841
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• 2004

IEC 60044-6 (Requirements for protective current transformers for transient performance) was established to Korea Standard (KS C IEC 60044-6 ; Instrument transformers Part 6 ; Requirements for protective current transformers for transient performance) in December 11, 2003. In this paper, requirements, test items and test methods protective current transformers for transient performance.

• Journal of Digital Contents Society
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• v.19 no.4
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• pp.615-620
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• 2018

Evaluation of clinical usefulness of current perception threshold test and vibration sense perception threshold test in diagnosing the diabetic poly-neuropathy patients is one of the diagnosis methods for diabetic poly-neuropathy. Up to the present, some diagnostic methods were used for diabetic poly neuropathy patients. For example, there are neuropathy impairment score test of lower limbs, nerve conduction test, cooling detection threshold test, heat-pain threshold test and so on. However, most of the above tests require very expensive cost and take a lot of time in test. In this paper, a new apparatus estimating vibration sense ability is introduced. For this purpose, the VCM(voice coil motor) stimulating patient's peripheral nerve and current amplifier were manufactured. Also, softwares sensing and driving the vibration detection threshold test in order to measure the quantitative vibration sensory levels in diabetic poly-neuropathy patients were developed.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1034-1035
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• 2015

Watertight 25.8 kV/600 A/12.5 kA fault current limiters (FCLs) have successfully installed in five areas (Incheon, Seoul, Gyeong-gi, Daejeon, Suwon) on KEPCO power distribution line for the purpose of commercial demonstrations. The fault current limiting operation of this FCL, which includes functions of sensing, commutation, and reduction of fault currents, is perfectly completed within 1 cycle immediately after fault occurs. The performance of FCL was verified by short circuit test, impedance test, insulation test, temperature-rise test, and control test, etc at PT&T in LS industrial systems, which is the official certification institute in Korea. In 2013, and also the FCL field test was performed in order to test the protection coordination between conventional relays and FCL, on the 1.5 kA and 5.0 kA faults, which were made by connecting the Artificial Fault Generator (AFG) to the distribution line in test grid at KEPCO Power Testing Center. The next step of this project is to check the FCL conditions caused by real external environment, and acquire the various data from five regions installed with FCL. In this paper, we intend to explain the FCL specifications and performance characteristics, and check the expected effect by application of FCL to power distribution line based on the power system analysis of an application site.

• Progress in Superconductivity and Cryogenics
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• v.3 no.2
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• pp.44-48
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• 2001

SMES consists of Superconducting magnet, a power converter, a cryostat and HTS current leads The prototype cryostat with HTS current leads and refrigerators was designed and manufactured for developing micro SMES. The temperature rise under dc current in HTS current leads was measured. The performances of helium boil-off and mechanical stress were evaluated during transfer and vibration tests. The results will be used to develope the micro-SMES system.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.242-243
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• 2012

In this paper, 200 W power supply for LED driver has been designed, analyzed, simulated and tested. Input AC voltage of 100VAC-240VAC was converted to DC voltage by high power factor converter. Output voltage was controlled, and output current was controlled by constant current when output current was reached to LED maximum rated current. By simulation and experimental test, voltage and current control and high power factor characteristics are verified.

• Fire Science and Engineering
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• v.24 no.2
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• pp.38-43
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• 2010

The purpose of this study is to secure the basis for judgment on the cause of an accident by analyzing the melting characteristics of a blade type fuse used for vehicles due to overload. In order to increase the reliability of the test, it was conducted by connecting the electrical system with conditions similar to those of an actual vehicle to apply the load. Carbonization pattern experiment of fuse by outside flame applied Korean Standard (KS). The fuse melted by the overcurrent showed a smooth cross-section while the test terminals, clear plastic body, etc., burnt out by the external flame was badly deformed. When 185% of the rated current (27.8A) was applied to a cable of 15A rated current onto which an over-capacity fuse (20A) was installed, the fuse melting time was 217 seconds. In addition, when a load current of 28.8[A] (139%) was applied, the fuse's test terminal and terminal blade were not burnt out although foam was observed on some parts of the plastic body. When a load capacity of 28.2[A] (141%) was applied to a cable of 15A rated current onto which an over-capacity fuse (30A) was installed, the fuse melting time was approximately 10 seconds. When a load current of 35.8[A] (119%) was applied, the fuse's test terminal and terminal blade were not burnt out, although some parts of the plastic body was swelled. However, it was observed that the switch terminal melted if approximately six minutes lapsed under such conditions. When a load capacity of 39.4[A] (131%) was applied to a cable of 15A rated current onto which an over-capacity fuse (30A) was installed, the fuse melted in approximately 69 seconds, and the test terminal and terminal blade were not burnt.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.5-8
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• 2005

This paper aims to introduce the Daegwallyeong wind turbine test site which is the first official wind turbine test site in Korea. The current status of test site, the characteristics, the projects performed and future plan of this test site are described. The results of wind condition measurements and monitoring system established by the Kangwon National University are presented. The importance of field test is also commented.