Effects of Different Sample Resistances on the Insulator Leakage Current Acquisition Results

Abstract:

The sampling resistor method is commonly used in the laboratory to measure the insulator leakage current. To study the effects of different resistance on the leakage current acquisition results, a series of experiments are systematically conducted in laboratory. Leakage current waveforms of a clean porcelain insulator under 9 kV and 27 kV power frequency voltages are acquired respectively through the oscilloscope with sampling resistance of 5 Ω, 10 Ω, 100 Ω, 1 kΩ and 17 kΩ. The results reveal that: rated voltage been applied, weak discharge exits on the surface of the porcelain insulator which leads to the appearance of the pulse in the leakage current waveforms and a larger sampling resistance weakens the pulse signal. When the voltage is 9 kV, the measurement result under 5 Ω sampling resistance is 49.4 times amplitude of the result under 17 kΩ sampling resistance and when the voltage turns to 27 kV, the ratio increased to 131.5.

• Periodical: Applied Mechanics and Materials (Volumes 644-650)
• Pages: 3468-3471
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.644-650.3468
• Online since: September 2014
• Authors: Peng Chao Miao*, Zhi Niu Xu
• Keywords: Insulator, Leakage Current, Resistance, Sample Resistor

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