Simplified Model for Steady State and Real-Time Ampacity of Overhead Conductors

Abstract

Recently the utility industry has recognized that there are substantial economic advantages that can be achieved by knowing the real-time temperature of a conductor when it is subjected to variations in current and weather conditions. Unfortunately realtime thermal models for the calculation of temperature of overhead conductors are usually quite complex. This paper proposes a simplified transient ampacity model that overcomes this difficulty. The model predicts both the steady state and transient thermal behavior of conductors that are subjected to a step change in current. The simplified model provides results that are within 15 percent of a more complex, detailed transient ampacity model.