Incorporating Temperature Variations Into Transmission-Line Models

This paper discusses a transmission-line modeling approach that incorporates available ambient temperature information. Several proposed line modeling techniques are studied and include distributed and lumped parameter models. In order to capture the nonuniformity of line parameters caused by temperature gradients, a model with multiple nonuniform segments is also proposed. An automated tool has been developed to obtain appropriate line model segmentation and parameter values of each segment, given a set of temperature measurements and their locations along the line.

I. Introduction

Transmission-Line models for large-scale system studies are characterized by uniformly distributed parameters or a lumped parameter configuration. The following assumptions are often made when deriving these line models: 1) uniform current density; 2) constant material characteristics; and 3) constant external conditions, including temperature. Line parameters are usually calculated at a predefined seasonal temperature.