Sag Measurement and Quantification in Transmission Lines: A Review

Sags are a serious issue and play a critical role for its cause due to multiple environmental factors such as extreme weather events: wind speed, blizzard, and heat loss. This paper provides a comprehensive review of sag measurements and its quantification methods. Current sag measurement and monitoring approaches are quantified using optical sensors, phasor measurement units, image processing techniques, smart grid technologies, and machine learning algorithms. The paper also proposes a futuristic sag measuring system that is hierarchical and categorized into a sensing, communication, control, and storage levels irrespective of the deployed sensing technology.