Dynamic Thermal Rating of Electric Cables: A Conceptual Overview

This paper provides a tutorial overview of dynamic thermal rating concepts and methods applied to electric cables. Although most analytical developments and models have been proposed many years ago and are covered by IEC Standards, numerous recent developments suggest refinements to these models and enhanced applications. In particular, on the modelling side, the latest contributions refer to analytic models, variants of the equivalent circuit of the soil to be used in finite difference methods, applications of 2D and 3D finite element methods, and definitions of simplified models and equations validated with respect to the results obtained from FEM simulations and experimental measurements. On the methodological side, the overview also covers optimal cable sizing, reliability aspects, risk estimation, and forecasting of dynamic cable rating.