Overview of on-line and off-line ampacity identification techniques of bare overhead transmission line

Abstract

The economics of power transmission requires operators to maximise the power through the network. Increasing knowledge of the impact of environmental factors on the current carrying capabilities of bare wire overhead lines is, therefore, important. Cost savings resulting from enhancing thermal transfer capabilities of transmission lines has motivated many utilities and power systems research centres to investigate techniques for maximising operational parameters. Enhancing power ratings of bare power conductors brings, alongside improved generated power dispatch flexibility, cost savings and economical and technical challenges. The aim of this paper is to examine some of the existing techniques employed to compute the ampacity of bare power lines and discuss practical limitations of these techniques. In addition, the impact of each technique will be considered from an operational prospective. On-line and off-line techniques are summarised and compared based on the nature and quality of power sources connected to the system, e.g. power output of windfarms tends to be of intermittent nature. Index Terms-Ampacity of bare power lines, dynamic thermal ratings, generation dispatch, ruling span of transmission line and thermal time constant.

Impact of Rain On Transmission Lines’ Ampacity: Scotland as a Case Study

“…It is also particularly useful to offset supply outages risks during adverse weather conditions when temporar system overload becomes inevitable. Research team in [13] stated that overlooking this parameter can have serious financial costs to utilities because it removes the needed flexibility during adverse weather conditions.…”