A Probabilistic Approach to Power Thermal Analysis and Ampacity Calculation

A technique is presented for calculating the temperature rise and load capabilities of power cables with provision for statistical variations of various soil, boundary and loading conditions. The novel. technique exploits the ampacity sensitivity algorithm described in a previous paper [1] in conjunction with statistical data gathered for a variety of soil materials, ambient parameters and load cycle characteristics. The technique provides useful information concerning the expected. values and confidence levels of. ampacity and cable temperature rise as well as the probabilities associated with excessive temperatures and thermal instability. The paper describes the probabilistic approach and illustrates a variety of its applications.