Summary

Surface contamination of high voltage DC power transmission lines could greatly influence the corona characteristic of conductor. Little is known about the effect of the surface condition of conductor on corona-generated UV characteristics. This paper presented the measurement of UV characteristics of negative DC corona discharge in pollution condition in a laboratory corona cage. To understand the relationship between UV characteristics and surface contamination of conductor, we researched the influence of deposition, relative dielectric constant and particle size of the contaminations on corona-generated UV characteristics. The relationships among these factors were consequently acquired. The pollution characteristics of the conductor were examined with a pollution experiment, which simulated the contamination deposition process by applying a negative DC voltage. The contamination, deposited on the surface of the conductor, was composed of salt, kaolin, and carbide. The photon number of the corona discharge was measured in the corona cage. The corona onset voltage obtain by the UV imager had a good agreement with theoretical results. The increase in the ash layer thickness had an impact on the conductor surface corona discharge and UV characteristics. The research results revealed that with the increased accumulation of contamination on the surface of the conductor, the UV photon number released by corona significantly increased, and the absolute value of the corona onset voltage decreased remarkably. The UV characteristics varied with different relative dielectric constants of contamination. As constants grew, the UV photon number increased obviously. The UV characteristics were proportional to the contamination particle size, so the photon number of corona discharge increased remarkably. The conclusion lays a foundation for widely applying UV imager in defect detection.

Additional informations

Publication type ISH Collection
Reference ISH2015_74
Publication year 2015
Publisher ISH
File size 775 KB
Price for non member Free
Price for member Free

Authors

Nakachi Toshiyuki, Kondo Kuniaki, Maeda Motohiro, Maistry Nattele

Influence of Surface Contamination of Conductor on Ultraviolet Characteristics of Negative DC Corona Discharge
Influence of Surface Contamination of Conductor on Ultraviolet Characteristics of Negative DC Corona Discharge