Experimental Evaluation of Available Computational Methods for Eddy Current and Hysteresis Losses for Cables Installed in Steel Pipes

This paper presents laboratory tests to evaluate the existing methods used to compute the eddy current and hysteresis losses produced by cables installed in steel pipes. The influence of the casing losses on conductor temperature is studied. The assumptions made by Moutassem and Anders are validated experimentally. This paper also shows a defect with the IEC Standard calculations of the pipe loss factor and thermal resistance. Finite element simulations are used to compare the laboratory experiments and illustrate the loss distribution in the casing. The application range of the available methods is established from the finite-element method models. As illustration, the proposed correlations are used for the rating of cables in trefoil or cradled formations inside a cylindrical steel pipe.