Natural Aging of Non-Energized Aluminum Conductors
This paper reports the results of a photographic and electrical study of the mechanism by which a new aluminum conductor ages. A systematic approach of monitoring the aging process revealed the movement of water drop location from the top of a new conductor to the bottom of an aged conductor. Through photographic water drop analysis and electrical test results it has been determined that an aluminum conductor, even though not energized, is essentially aged in 4 to 7 months in the environment of northern Indiana, USA. A seasonal effect was found to add up to 5 months to this period.
Statistical Analyses of Audible Noise and Corona Loss Data for a 10-Conductor UHV Bundle
Statistical analyses of long-term audible noise and corona loss data for the 10 × 46.3 mm conductor bundle, supported in a symmetrical 1.22 m diameter circle, under a variety of weather conditions and for a number of voltage levels are presented. Also included are audible noise and corona loss as functions of rain rate. Some evaluations of performances of new and aged conductors are presented. Based on the results, the conductor performances of an assumed three-phase line are projected.
Predetermination of Corona Losses Under Rain: Influence of Rain Intensity and Utilization of a Universal Chart
This paper deals with the corona losses of EHV lines in wet conditions. Using a calculation method presented in [1] and [2] and numerous measurements made in a test station, it is shown that surface state coefficients can be defined versus the aging of conductors and the intensity of rainfalls. Knowledge of the surface state coefficients allows the calculation of corona losses in rain of any EHV line.