• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.5
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• pp.179-184
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• 2016

The usual way used by electric power stations to deliver high levels of generated power is via 6.6kV XLPE (or CV) cables. Depending on the manufacturing technique, installation environment, and usage conditions, the deterioration processes of the power cables start from the instant of operation. Cable junctions may break down in three years from the start of operation due to the manufacturing or construction defects. Otherwise they should be in good working order for 20-30 years. When the cable system (the cable itself and cable junctions combined) deteriorates, fire accidents happen due to the dielectric breakdowns. We have invented a device to monitor the deteriorating status of cables at Korean Western Power Co. Ltd. located in Taean, Chungcheongnam-do province. In this paper, we introduce the device hardware. Using the device, we have measured the insulation resistance and humidity in the sheath of the cables. We present, in analysed results, the effect of humidity on insulation resistance in cable sheaths.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.4
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• pp.199-203
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• 2015

With the development of industry these days, the demand for electric power increases and the larger capacity for power transfer is required. The scales of facilities should become larger; and the relative systems are required to operate with a higher degree of reliability. Therefore, stabilization of electric power systems is an important issue. The high degree of reliability required in the process of production and supply of electric power is an essential part of industrial society. Accident such as blackouts causes a hugh amount of economic losses to the high-tech industrial society dependent upon electric power. This paper is about the basic study of the relations between the load current and lifetime of power cables in operation. In order to do the research, we installed a current transformer and an equipment for measuring temperature at the 6.6. kV cables in operation. The two equipments have been installed on the cable systems in operation for the last 20 years. Since the insulation resistance of most of the cables showed the value larger than the threshold, it was not easy to tell the remaining lifetime of cables. The load current of the cables was almost constant. The surrunding temperature was $15{\sim}25^{\circ}C$, little variation of temperature values.