• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2361-2363
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• 1999

The conventional SiC-type of lightning arresters in distribution systems has been replaced by ZnO-type because the ZnO-type has characteristics such as outstanding non linearity, high energy absorption capability, surge suppressing performance, and excellent response to abrupt wave. Out of the various types of lightning arrester failures, some which have been often reported could be prevented in advance. Therefore, the preventive countermeasures which can cope with the failures are strongly required. This paper summed up and analyzed the lightning arrester failures which occurred, from 1983 to 1992, in distribution systems in order to provide fundamental data, classified by year, to make countermeasures.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1265-1267
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• 1994

EPDM has excellent electric characteristics and so that it has been rapidly finding use is high voltage applications in recent years. At present EPDM is widely used for insulator of cable and accessories, and further the commercial use of Premolded housing for elbow surge arrester is started. In this paper, we have measured the temperature, pressure and voltages dependence of $tan{\delta}$ in EPDM. As a results, dielectric characteristics($tan{\delta}$) increases slightly with increasing the temperature. However, it is almost independent of the pressure and voltages.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2035-2037
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• 2000

This paper describes the effect of lightning impulse current on deterioration of ZnO blocks for distribution arrester. In this study. a multiple-lightning impulse current generator which can produce quadruple 8/20 ${\mu}s$ 5 kA is designed and fabricated, and total energy applied to the arrester block at each pulse is about 1,217 J. The experimental results indicate that the type of arresters are more vulnerable to deteriorate or damage at multiple-lightning impulse current.

• Proceedings of the KIEE Conference
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• 1995.07b
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• pp.631-633
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• 1995

In this paper, the results of development of arrester leakage current detector using micro computer are described. This detector is based on harmonic analysis of the leakage current by FFT. For low sensitivity to disturbance, this device used optical fiber. This will be a great benefit of detecting deterioration ZnO arrester.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.783-788
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• 2005

Detection of small leakage current is the most important technique in arrester diagnosis. Various types of leakage current detector have been commercialized, but they are not available for the railway arresters including voltage harmonics, and do not furnish enough information needed for arrester diagnosis. This paper describes the development of a leakage current detector which is suitable for the railway arresters. The detector is consisted of a sensor unit with amplifier, an optical linker and main analyzer. Frequency bandwidth and measuring range of the detector is 9[Hz]$\~$850[Hz] and 50[uA]$\~$5[mA], respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.644-647
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• 1999

The main objective of this paper is to design and test a new type of polymer ZnO surge arrester for DC power system of railroad vehicles. The rated voltage is 1500v direct current. The main research works are focused on structure design by finite element method, rat ing vol tape, temporary over vol tape and studies of character int ice of polymeric surge arrester .

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.2
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• pp.257-263
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• 2016

This paper describes the lightning arrester transients in cable head termination. The installation references of cable head tower and lightning arresters are firstly reviewed, then the performance of lightning arrester operation is also evaluated based on lightning overvoltage analysis by the change of grounding lead cable length. This paper finally proposes the optimal length of grounding lead cable at the cable head termination. The limited lightning current is also proposed according to the change of grounding lead cable length. The results will contribute to protecting insulation breakdown failure against lightning surge at the terminations and joints.

• International Journal of Air-Conditioning and Refrigeration
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• v.11 no.1
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• pp.40-49
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• 2003

Dynamic characteristics of water hammer arresters installed in a building water supply system have been investigated numerically by utilizing a commercial code that employs the method of characteristics. Some preliminary results with those arrester models produced in this study agree well with the previously reported. Then, the arrester models have been incorporated into a water supply pipe system of a 59 $m^2$apartment unit constructed by a leading construction company, and their dynamic characteristics have been investigated, especially on the reduction in the water hammer pressure. It is found that the setting of the arresters in the pipe system, which is recommended by the company, may not be proper for reducing the pressure down below 1,082.0 kPa (10.0 kg$g_f$/$cm^2$) when quick-closure valves in the pipe system are closed within 30 ms at the static pressure of 542.6 kPa (4.5 kg$g_f$/$cm^2$). More arresters in the system may be required to meet pressure criteria stated on the related standards and codes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.82-85
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• 1997

This paper describes the development of new type arrester for 22.9kV class distribution lines, with polymer insulating materials applied to their housings. The new arrester employs silicone insulating material for its housing, instead of the conventional porcelain housing, aiming at reduction in size and weight and explosion proof against internal short circuit failure. And, since the design of sheds is not restricted. it is possible to provide a long surface leakage distance per strike length and improve anti-contamination performance.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1519-1521
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• 1998

A Gapless HST(high speed train) arrester design is not possible without the highly non-linear ZnO(ZincOxide) varistors. Zno varistors combine excellent protective characteristics with steady state performance to maximize protection, the ZnO varistors are selected for each unit based on leakage current and residual voltage, to verify that the residual voltage is the residual voltage published for HST arrester.