Transmission Line Sag Calculation with Ampacities of Different Conductors

  • Sandeep GuptaEmail author
  • Shashi Kant Vij
Conference paper
Part of the Communications in Computer and Information Science book series (CCIS, volume 899)


Whenever a transmission line conductor is erected between two towers; due to action of gravity on conductor weight; transmission line is not a straight line joining the two points but it slackens which is termed as sag. It is the lowest point between the two towers and nearest to the ground. It is both the advantage and disadvantage due to the presence of sag in transmission line as on the one hand it maintains the safe tension level and on the other hand to maintain the greater ampacity and required ground clearance transmission lines are to be erected at towers on greater heights. In this paper, different factors are explained which affects the transmission line sag. This paper focuses on calculating the sag produced by transmission lines using different types of conductors such as ACSR, ACCC and ACSS under different conditions. There is also a comparison between various conductors in which sag develops. Effect of loading on the development of conductor sag will also be considered in this paper. This paper uses MATLAB programming for the calculating the results and graphical outputs and simulation results and modeling for the comparative study among various conductors. The importance of this paper is that it will help in deciding the kind of conductor which is to be used for any particular power system design especially for the transmission network with sag.


Sag Different conductors (ACSR, ACCC and ACSS) Ampacities and transmission line 


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Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.Department of Electrical EngineeringJECRC UniversityJaipurIndia

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