• Proceedings of the KIEE Conference
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• 1997.07e
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• pp.1642-1644
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• 1997

The simulation study of lightning faults reducing effects by the installation of surge arresters on the 154 kV transmission line is stated here. For the purpose of detailed simulation of arcing horn, a flashover model with dynamic characteristics of arcing horn gap was represented as a non-linear inductance which is controlled by EMTP/TACS(Electromagnetic Transient Program/fransient Analysis of Control Systems) switches. The back flashover inducing current was increased from 50 kA to 88 kA by the installation of surge arresters on the transmission line which has one ground wire and 20 ohms of tower footing resistances. The great advantage of surge arrester installation on one circuit of the double circuit transmission line is to prevent the simultaneous back flashover up to 190 kA.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.581-586
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• 2006

Selection and application recommendations of lightning arresters for DC electric traction vehicles are presented. To decide arrester specification such as continuous operating voltage(COV, $U_c$), rated voltage($U_R$), and nominal discharge current($I_n$), variations of system voltage and surge currents flowing arresters were analyzed in running-service of traction vehicles. System voltages increased up to 1,800V during anti-breaking. Surge currents recorded 3 times per running-service-route and their magnitudes were ranges of $150A{\sim}2kA$. From the field measurement and consideration of EN50163, COV, $U_c$, and $U_R$ for the $1,500V_{DC}$ traction vehicles were proposed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.556-557
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• 2005

The distribution facilities, such as suspension insulator, line post insulator, lightning arrester, COS, used for long periods in the industrial pollution area were investigated. The electrical test and the material analyses were performed on the polluted and non-polluted facilities. The low frequency dry flashover voltage of polluted suspension was decreased about 8% in comparison with non-polluted one. The polluted materials turned out with the iron which came from the foundries. The polluted materials turned out with the iron which came from the foundries. This conductive materials decreased the leakage distance, resulting in reducing of electrical properties.

• Proceedings of the KIEE Conference
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• 1986.07a
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• pp.365-368
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• 1986

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.558-560
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• 2003

The effects of surge arresters for protection of transmission systems against direct lightning strokes have already been investigated using the digital simulation program EMTP. Distribution lines are spanned on a much large area as compared to transmission lines, and therefore, are more often susceptible to lightning strokes. This paper analyzes the overvoltages on underground cable system against direct lightning strokes to the overhead ground wire using the digital simulation. The effects of lightning protection methods, such as lowering the grounding resistance and installing the surge arrester, for preventing overvoltages on underground cable system caused by direct lightning strokes to the overhead ground wire is investigated. Several schemes have been proposed to protect underground cables. This paper summarizes the main results of a study aimed at analysis of lightning overvoltages in variety underground feeders protected by metal-oxide arresters. This study will provide insulation coordination methods for reasonable system design in 22.9kV underground cable system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.1
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• pp.1-7
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• 2013

This paper analyzes the flashover rate by lightning in Korea distribution system. Because of random characteristics of lightning, the Monte Carlo method is applied to estimate the lightning performance. The magnitude of lightning stroke is based on the curve measured in field. The classification of direct and indirect lightning depends on the striking distance. The striking distance and flashover rate are calculated by using the method based on Central Research Institute of Electric Power Industry(CRIEPI). The distribution system and lightning is modeled by using EMTP and MATLAB, and the accuracy of modeling is discussed. The simulations for the various spacing between two adjacent surge arresters and the various grounding resistance of GW according to the existence of GW are performed and the simulation results are analyzed.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.1
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• pp.75-81
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• 2007

This paper dealt with the design and implementation of an expert system to monitor and diagnose the lightning arresters in GIS substations. The expert system consists of a data acquisition module(DAM) based on microprocessor and diagnostic algorithms. The DAM measures and analyzes several parameters necessary for the arrester diagnosis such as system voltages, leakage current components, and temperatures. Also, it includes an intelligent surge counter which can record the date and tin, the polarity, and the amplitude of surge currents. All the data acquired is transmitted to a remote computer by a low rate wireless network specified in IEEE 802.15.4 to avoid electromagnetic intereference under high voltage and large current environments. The decision-making for the arrester diagnosis completes with a Java Expert System Shell(JESS) which is composed of a knowledge base, an inference engine and a graphic user interface(GUI).

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.2
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• pp.104-110
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• 2004

This paper describes the lightning overvoltage occurred differently according to installation methods of arresters and overhead grounding wire in case of double circuits distribution systems. First, the analysis models are established considering the severe case between upper and lower distribution line, when the direct lightning surge strikes to the overhead grounding wire. The lightning overvoltage is variously analyzed with the change of grounding interval and resistance, arrester installation interval as well as the magnitude of surge using EMTP. After simulation results are compared with the BIL which is now used at field, the authors propose the methods for suitable shielding in domestic distribution systems.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1718-1720
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• 2001

The route of surge arrester connection is very important because bends and kinds of leads increase the impedance to lightning surges and tend to nullify the effectiveness of a grounding electrode conductor. There is a need to know how effective installation of lightning surge arresters is made in order to control voltage and to absorb energy at high lightning currents. The effectiveness of a grounding conductor and bonding for 18[kV] metal oxide distribution line arresters was experimentally investigated with lightning and oscillating impulse voltages.

• Journal of the Korean Society of Safety
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• v.12 no.1
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• pp.29-36
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• 1997

Precision electronic equipments for outdoor use are composed of sophisticated microcircuits that are extremely vulnerable to lightning-caused voltage spike. This transient voltage spike may cause upset, latent failure or Interference on electronic equipments. In order to develop efficient lightning protection measures on AC power lines of a road traffic controller as a electronic equipment for outdoor use, experimental surge immunity tests were conducted according to IEC standard 801-5. The combination of gas tube arrester and metal-oxide varistor was installed at the input of AC power lines and the silicon avalanche suppressor installed at the output of DC power supply for the lightning protection measures.