The differences between IEEE and CIGRE heat balance concepts for line ampacity considerations

Abstract

Both IEEE and CIGRE have developed the line ampacity standards based on the same concept of the heat balance equation considering the balance between heat absorbed and dissipated. This document presents the differences in aspect of the heat balance equation, solution and application for ampacity calculation between the newest IEEE Standard for Calculating the Current-Temperature of Bare Overhead Conductors — IEEE Std 738™-2006 which is the revised version of IEEE Std 738™-1993 and CIGRE Mathematical Model for Evaluation of Conductor Temperature in the Steady (or Quasi-Steady) State (Normal Operation).